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Regional Safety Marks

Americas, Europe & Asia

The maps in the folling section highlight some of the more notable safety marking schemes but is not allinclusive. In addition, in Europe there are other marks applicable in the Nordic countries and other central and eastern European countries such as Denmark, Switzerland, Hungary, Ukraine and Belarus. In Asia, countries including Hong Kong and India operate their own safety marks.

CONTENTS

Europe

AsiaPac ®

Americas

CONTENTS

Norway

Canada

page 11

Mexico

Brazil

TECH REPORT

Russia

Power Supply Safety Standards and Marks

Germany

Argentina

TECH SERIES

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TECH REPORT

Power Supply Safety Standards, Agencies, and Marks The ability to sell power supplies, either built-in or external types, around the world depends on meeting the relevant safety standards that apply in those territories. These standards are defined and administered by national or international agencies with various government-recognized testing laboratories able to certify compliance with such statutory regulations. The primary goal of safety standards for power supplies used in electrical equipment is to protect against fire, electric shock and injury. Products meeting these requirements may be identified by a safety mark from the associated standards organization or by a mark indicating compliance with local legislation, within a defined economic area or trading zone. Understanding the complexities and subtle differences between various standards and marking schemes can be daunting. This application note aims to identify the major standards that relate to power supply safety, the agencies that administer them and/or provide certification, and the marking schemes that can be used to show compliance.

Laboratories (UL) and Canadian Standards Association (CSA) provide certification in North America, while similar bodies in Europe are Verband der Elektrotechnik (VDE), Technischer Überwachungs-Verein (TUV) and British Standards Institution (BSI). A product meeting an IEC standard such as IEC60950 may be identified with the standard’s number prefixed instead by UL, CSA or EN (European Norm) to indicate the country where it is certified e.g. UL60950 or EN60950. Standards like these with the same numbers but different prefixes are sometimes referred to as “harmonized standards.” But while the IEC continues to pursue harmonization, regional differences remain and consequently products intended for multiple markets will need to show all of the required certifications.

Major Safety Standards

IEC60950-1:

The International Electrotechnical Commission (IEC) and the associated International Organization for Standardization (ISO) are the principle agencies responsible for electrical safety standards. Agencies such as Underwriters

Safety of Information Technology Equipment IEC60950-1 consolidates the 2005 2nd edition of this standard with its first and second amendments (from 2009

Power Developer and 2013 respectively). The standard is applicable to mains, or battery-powered information technology (IT) equipment and office machines with a rated voltage not exceeding 600 V. It is intended to prevent injury and damage to persons and property from such hazards as electric shock, fire, dangerous temperatures and mechanical instability. Note that in Germany this standard is also referenced as DIN EN60950-1 and as VDE0805.

power supplies, especially mains units, isolate secondary circuits and accessible parts from dangerous AC mains voltages:

Classes of Equipment

Class II equipment provides protection using double or reinforced insulation and hence no ground is required.

The standard identifies different classes of equipment depending on how their

Class I equipment achieves electric shock protection through basic insulation and protective earth grounding. This requires all conductive parts that could assume a hazardous voltage in the event of basic insulation failure to be connected to a protective earth conductor.

Circuit Definitions Hazardous Voltage

Any voltage exceeding 42.2 Vac peak or 60 Vdc without a limited current circuit.

Extra-Low Voltage (ELV)

A voltage in a secondary circuit not exceeding 42.4 Vac peak or 60 Vdc, the circuit being separated from hazardous voltage by at least basic insulation.

Safety Extra-Low Voltage (SELV) Circuit

A secondary circuit that cannot reach a hazardous voltage between any two accessible parts or an accessible part and protective earth under normal operation or while experiencing a single fault. In the event of a single fault condition (insulation or component failure) the voltage in accessible parts of SELV circuits shall not exceed 42.4 Vac peak or 60 Vdc for longer than 200 ms. An absolute limit of 71 Vac peak or 120 Vdc must not be exceeded. SELV circuits must be separated from hazardous voltages, e.g. primary circuits, by two levels of protection, which may be double insulation, or basic insulation combined with an earthed conductive barrier. SELV secondaries are considered safe for operator access. Circuits fed by SELV power supply outputs do not require extensive safety testing or creepage and clearance evaluations.

Limited Current Circuits

These circuits may be accessible even though voltages are in excess of SELV requirements. A limited current circuit is designed to ensure that under a fault condition, the current that can be drawn is not hazardous. Limits are detailed as follows: • For frequencies < 1 kHz the steady state current drawn shall not exceed 0.7 mA peak ac or 2 mA dc. For frequencies above 1 kHz the limit of 0.7 mA is multiplied by the frequency in kHz but shall not exceed 70 mA. • For accessible parts not exceeding 450 Vac peak or 450 Vdc, the maximum circuit capacitance allowed is 0.1 μF. • For accessible parts not exceeding 1500 Vac peak or 1500 Vdc the maximum stored charge allowed is 45 μC and the available energy shall not be above 350 mJ. To qualify for limited current status the circuit must also have the same segregation rules as SELV circuits. To qualify for limited current status the circuit must also have the same segregation rules as SELV circuits.

TECH REPORT Class III equipment operates from a SELV (Safety Extra Low Voltage) supply circuit, which means it inherently protects against electric shock, as it is impossible for hazardous voltages to be generated within the equipment.

against electric shock.

Understanding the standard and the above classes of equipment requires a clear understanding of the circuit definitions, types of insulation and other terminology used in relation to power supplies.

There are five types of insulation to shield live components with hazardous voltages from other components and circuits as follows:

Double Insulation Comprising both basic insulation and supplementary insulation. Reinforced Insulation Single insulation system applied to live parts, which provides a degree of protection against electric shock equivalent to double insulation.

For power supplies, the minimum insulation requirements are:

Operational/Functional Insulation Is only necessary for the correct functioning of the equipment and does not provide any protection against electric shock. Basic Insulation Insulation applied to live parts to provide basic protection

Supplementary Insulation Independent insulation applied in addition to basic insulation in order to provide protection against electric shock in the event of a failure of basic insulation.

Insulation and Isolation

Primary to secondary: Reinforced insulation with a minimum dielectric strength of 3000 Vrms. Primary to ground: Basic insulation with a minimum dielectric strength of 1500 Vrms.

Other Key Terminology Protective Earth

Class I equipment must have a protective earth conductor, if insulated it must be green/ yellow or transparent covering. No switch or fuse is allowed. Resistance between earthed parts and the earth termination must not exceed 0.1 ÎŠ, which is tested by a current 1.5 times the current capacity of any hazardous voltage circuit at the point where failure of basic insulation would make the earthed part live. Test voltage maximum is 12 V. Test current may be ac or dc but must not exceed 25 A.

Clearances (through air)

Power products are intended for general application and should be designed for worst case conditions (pollution degree 3 and mains voltages up to 264 Vac) for minimum clearances of: â&#x20AC;˘ â&#x20AC;˘

4.00 mm for reinforced or double insulation 2.00 mm for basic and supplementary insulation

Where formal quality control processes are in place relaxation to 3.4 mm and 1.7 mm is allowed, but reinforced insulation is then subjected to 100% electric strength testing. If an air gap serves as the insulator between a hazardous voltage and the enclosure, the required clearance is 10 mm.

Power Developer Other Key Terminology (Continued) Creepage Distances

Tables of creepage distances for basic insulation are given for various pollution conditions and materials, the distances depending on working voltages. These distances are doubled for reinforced insulation.

Flammability

The standard requires that the equipment design: • • •

Avoids high temperatures, or shields and separates flammable materials from high temperature parts. Uses materials of low flammability both internally and for enclosures. Uses fire enclosures to limit the spread of fire.

Compliance can be achieved by using V-2 or better rated insulating and printed board materials throughout and ensuring adequate spacing between high temperature components and plastic and painted parts. Use of UL listed materials eliminates the necessity for exhaustive and messy flammability testing. Earth Leakage Current

For Class II equipment this shall not exceed 0.25 mA, for hand held Class I equipment 0.75 mA, and other Class I equipment 3.5 mA. The test for Class II equipment requires conductive metal foil to be attached to an area not exceeding 10 x 20 cm on accessible non-conductive parts and the test is made between this and conductive parts. Tests are carried out at the most unfavorable (highest possible) supply voltage.

IEC60601-1: Safety of Medical Electrical Equipment Edition 3.1 of this standard comprises the 2005 3rd edition with its 2012 amendment 1 which supersedes the 2nd edition that expired in Europe in June 2012, Canada in April 2013, and the USA in December 2013. It covers the basic safety and essential performance applicable to medical electrical equipment including surgical, monitoring and hospital equipment. IEC60601-1 follows the same requirements established in IEC60950-1 but with increased levels of protection for insulation/ isolation, creepage, clearance and leakage current. Equipment required to meet IEC60601-1 is any equipment that will be operated within an area in which patients are normally cared for. The Patient Vicinity is the space with surfaces likely to be

contacted by the patient or an attendant who can touch the patient. This encloses a space within the room 1.83 m (6 feet) beyond the perimeter of the bed (or examination table, dental chair, etc.) in its intended location, and extending vertically 2.29 m (7.5 feet) above the floor. All IEC0601-1 power systems must have dual fused input protection with reduced leakage currents of ≤300 µA to ground (earth) and ≤100 µA to the chassis to meet the legislated specifications.

Differences Between 2nd and 3rd Editions The changes in power supply classification from the 2nd edition to the 3rd edition deal with definition, not performance. Both the 2nd and 3rd revisions require two mechanisms for guarding each in the event of a failure. For the area of basic electrical safety and avoiding shock hazard, the 3rd edition further divides means of

TECH REPORT

Power Supply Safety Standards, Agencies and Marks Power Supply Safety Standards, Agencies and Marks Differences Between 2ndnd and 3rdrdEditions Differences 2 classification and 3 Editions The changes inBetween power supply from

Instead of these classifications, the third edition Insteadmedical of thesedevice classifications, the third edition requires manufacturers to define requires medical device manufacturers to define the classification in terms ofthat “Means of Operator power supply solution would be the classification in terms of “Means of Operator Protection” (MOOP) and “Means of Patient Protecappropriate, depending on whether one Protection” and “Means of Patient Protection” (MOPP) (MOOP) as determined by an ISO-14971 Risk or two levels of protection are required. tion” (MOPP) as determined by an ISO-14971 Analysis / Management process. The table belowRisk Analysis / Management process.and Thethe table below summarizes these classifications type of summarizes these classifications and the type of power supply solution that would be appropriate, IEC61010-1: power supply solution that would be appropriate, depending on whether one or two levels of protection depending are required.on whether one or two levels of protection Safety of Measurement, are required.

rdpower supply classification from The changes 2nd edition to in 3into edition deal withprotection definition, not protection operator and nd rd nd edition to 3Both edition definition,require not 2performance. andwith 3rd revisions the 2deal patient protection. is the nd performance. Both 2This andeach 3rdbecause revisions require two mechanisms forthe guarding in the event of potential hazards seen by each can be two mechanisms for guarding each in the event of a failure. For the area of basic electrical safety and aquite failure. For thehazard, area basic electrical safety and different; anofthe operator has access to further divides avoiding shock 3rd edition rd avoiding shock hazard, the 3 edition further divides means of protection into operator protection and a control panel, for example, while the means protection into protection and patient of protection. This is operator because the potential patient may be This “connected” via probes. patient is be because the potential hazardsprotection. seen by each can quite different; an hazards by eachtocan be quite different; an operatorseen has access a control panel, for example, Patient leakage various operator access tobea“connected” controlfor panel, example, while the has patient maycurrents viafor probes. while the patient may be “connected” via probes. equipment categories were defined Patient leakage currents for various equipment catin the leakage second edition as follows: egories were defined in the edition as follows: Patient currents forsecond various equipment categories were defined in the second edition as follows:

Classification Requirements Classification Requirements Type B

Type BF

Type CF

Type B Isolation: 1500 Vac

Type BF Isolation: 3000 Vac

Type CF Isolation: 4000 Vac

Isolation: 1500 Vac Creepage: 2.5 mm

Isolation: 3000 Vac Isolation: 4000 Vac Creepage: 5 mm Creepage: 8 mm

Creepage: 2.5 mm Basic Insulation

Creepage: 5 mm Double Insulation

Basic Insulation

Double Insulation

2nd Edition Requirements by Classification

Control, and Laboratory IEC61010-1: Equipment

IEC61010-1: Safety of Measurement, Control and Laboratory Equipment

IEC61010-1 is another safety standard Safety of Measurement, along similar lines to the above IEC60950 Control and Laboratory and IEC60601 standards but reflecting Equipment requirements in this instance for IEC61010-1 is another safety standard along measurement, control and laboratory similar lines toisthe abovesafety IEC60950 and IEC60601 IEC61010-1 another standard along equipment, including instruments standards but reflecting requirements in this similar lines to the above IEC60950 and IEC60601 such as meter and oscilloscopes but instance for but measurement, control and laboratory standards reflecting requirements in this equipment, including such aslaboratory meter also extending to instruments x-ray equipment. instance for measurement, control and and oscilloscopes but also extending to x-ray equipment, against including electrical instrumentsshock, such asfire meter Protecting equipment. Protecting electricaltoshock, and oscilloscopes butagainst also extending x-ray and mechanical or injury, IEC61010 fire and mechanical or burn burn injury, IEC61010 also equipment. Protecting against electrical shock, also addresses hazards related to fluids, addresses hazards related to fluids, lasers and fire and mechanical or burn injury, IEC61010 also

Creepage: 8 mm Double Insulation Double Insulation

2nd Edition Requirements by Classification

addresses hazards related to fluids, lasers and Classification

Classification

Insulation

Isolation

Creepage

Solution

One MOOP

Basic

1500 Vac

2.5 mm

IEC60950-1 Rated Power Supply

One MOOP Two MOOP

Basic Double

1500 Vac 3000 Vac

2.5 mm 5.0 mm

IEC60950-1 Rated Power Supply IEC60601-1 Rated Power Supply

Two MOOP One MOPP

Double Basic

3000 Vac 1500 Vac

5.0 mm 4.0 mm

IEC60601-1 Rated Power Supply IEC60601-1 Rated Power Supply

One MOPP Two MOPP

Basic Double

1500 Vac 4000 Vac

4.0 mm 8.0 mm

4000 Vac

8.0 mm

IEC60601-1 Rated Power Supply IEC60601-1 Rated Power Supply plus an IEC60601-1 Rated Dc-Dc Converter IEC60601-1 Rated Power Supply plus an IEC60601-1 Rated Dc-Dc Converter

rd MOPP Double 3Two Edition Requirements by Classification

3rd Edition Requirements by Classification

Instead of these classifications, the third edition requires medical page 6 device manufacturers to define the page 6 classification in terms of “Means of Operator Protection” (MOOP) and “Means of Patient Protection” (MOPP) as determined by an ISO14971 Risk Analysis / Management process. The table below summarizes these classifications and the type of

lasers and UV light as well as those that may arise from the measuring circuit. Not all these hazards are directly relevant to the equipment’s power supply but fortunately the latest 3rd edition of the standard separates the general equipment requirements from the more specific measurement circuits, which are now covered by

Power Developer

IEC508: Safety Standard for Industrial Control Equipmen

UV light as well as those that may arise from the measuring circuit. Not all these hazards are directly relevant to the equipmentâ&#x20AC;&#x2122;s power supply but fortunately the latest 3rd edition of the standard separates the general equipment requirements from the more specific measurement circuits, IEC508, mostsafety commonly referred to as UL 508, is IEC61010-2. The 3rd edition also as UL 508, is the standard for which are now covered by IEC61010-2. The 3rd the safety standard for industrial control and fact defines more stringent control and factory automation edition also defines more requirements stringent requirements industrial automation equipment, which includes devices su respect to fire hazards: ininrespect toshock shockand and fire hazards: equipment, which includes devices as motor starters and controllers, overload relays such as motor starters andand controllers, circuit control switches relays, other switche Creepage, clearances, and dielectric values overload relays, circuit control switchestransform for sensing (pressure, flow, proximity), depend on insulation type as well as whether and relays, other switches for sensing and rheostats and programmable controllers. UL mains or secondary derived from mains. Shock 508 covers requirementstransformers for devices rated at 150 (pressure, flow, proximity), V or less, and for use in ordinary location and rheostats andintended programmable Voltage for determining limited energy at an ambient temperature of 0~40Â°C. UL 698 controllers. UL 508 covers requirements values changed to be more logical. covers equipment intended for use in hazardous for devices rated at 1500V or less, and Fire (limited energy means a fire is unlikely) locations. UL 508 provides protection against sho is intended forground use infaults ordinary locations circuits, and overload as well as at an ambient temperature of 0~40ÂşC. thermal protection and defines requirements for IEC60065: things as endurance testing and accelerated UL 698such covers equipment intended aging, dielectric voltage-withstanding and leakag Safety of Audio, Video, and for use in hazardous locations. UL current limits. UL 508 focuses heavily on 508 provides protection against short ratings a Similar Electronic Apparatus test limits that are not necessarily relevant to pow circuits, ground faults, and overload IEC60065 is intended to protect against supplies, e.g. short-circuit current ratings (SCCR) as wellswitches as thermal protection and and relays. fire, electric shock and injury, this time IEC60065 is intended to protect against fire, electric

IEC60065: Safety of Audio, Video and Similar Electronic Apparatus

defines requirements for such things inshock respect to audio, similar and injury, this video time inand respect to audio, video as endurance testing and accelerated and similar equipment, such examples equipment, includingincluding such examples as aging, dielectric voltage withstanding, as video projectorsand andelectronic electronic flash units for video projectors flash and leakage current limits. UL 508 photographic purposes. As with the standards units for photographic purposes. As already discussed, not all of the protective focuses heavily on ratings and test limits with the standards already discussed, measures are applicable to power supplies but that are not necessarily relevant to not allthat of the protective measures aresimilar those relate to shock and fire require powerUL supplies, e.g. short-circuit 1310 specifies requirementscurrent covering indoor applicable power supplies but those precautionsto with respect to insulation, isolation, ratingsand (SCCR) foruse switches and relays. outdoor Class 2 power supplies and that relate to shock fire require limiting voltage and/orand current, and measures to battery chargers in applications such as lighting increase resistance towith fire. IEC60065 references similar precautions respect to systems, machinery and other appliances installe UL 1310: other standards such as: IEC60950-1 for SELV insulation, isolation, limiting voltage in residential and industrial environments. These voltage limits, TNV (Telecommunication Network and/or current, and measures to units utilize an isolating transformer and other Voltages) for equipment that is not connected to Safety Requirements for Class increase resistance to fire. IEC60065 components to provide either ac or dc outputs, the mains and IEC60695-11-10 for component 2 Power Units subject to a maximum rating of 42.4 Vac peak or references standards such as: flammabilityother categories. 60specifies Vdc. The standard is aimedcovering at products UL 1310 requirements IEC60950-1 for SELV voltage limits, TNV indoor and outdoor use Class 2 power (Telecommunication Network Voltages) supplies and battery chargers in for equipment that is not connected page 7 applications such as lighting systems, to the mains and IEC60695-11-10 for machinery and other appliances component flammability categories. installed in residential and industrial environments. These units utilize IEC508: an isolating transformer and other Safety Standard for Industrial components to provide either ac or dc outputs, subject to a maximum Control Equipment rating of 42.4 Vac peak or 60 Vdc. IEC508, most commonly referred to

UL 1310: Safety Requirements for Class 2 Power Units

TECH REPORT

s tory uch s, es mers

The standard is aimed at products that primarily power low voltage, electrically operated devices including: •

00 ns

ort

d ge and wer ) for

•

Portable or semi-permanent direct plug-in units with 15 A blade connections for use on nominal 120 or 240 Vac mains circuits. Cord-and plug-connected units with a 15 or 20 A plug for 120/240 Vac mains supply. Units permanently connected to an input supply nominally of 600 Vac or less.

Direct plug-in and cord-connected units also include DC-powered supplies operating from a vehicle battery via a cigarette lighter or equivalent DC connector or from a data port associated with information technology equipment. These units are also limited to a maximum input power of 600W. •

The safety requirements of UL 1310 are defined in terms of:

•

Enclosure strength and rigidity to resist likely abuses.

•

Built-in overcurrent and overtemperature protection devices.

•

A maximum potential of 42.4 Vac peak / 60 Vdc for exposed wires / terminals.

•

Protection from “backfeed” voltage.

Other aspects covered by the standard include: packaging, corrosion, switches, weight, DC cabling, mounting, connections, strain relief, operating temperature, humidity and environment (indoor and outdoor).

Other Similar Equipment Safety Standards UL8750: Safety for Solid-State Lighting (SSL) UL 8750 was introduced in 2006 as legacy lighting standards did not address solidstate lighting i.e. LEDs and equipment that is an integral part of a luminaire or other lighting equipment, which operates in the visible light spectrum between 400 ~700 nm. The standard’s certification programs cover: LED packages, arrays and drivers; light engines and holders; integral and self-ballasted lamps; and retrofit products. Of particular note, UL 8750 calls for LED power supplies and drivers to be compliant with UL 60950-1.

UL 879: Safety of Electric Sign Components UL 879 covers components for use in signs and outline lighting systems intended to convey a message or outline the structural features of a building. Light sources addressed by the standard include: fluorescent, high intensity discharge (HID), neon, cold cathode lighting, light emitting diodes (LEDs) and electroluminescent lighting. Components covered include the materials used in the structure of the signs, the sign face, its frame, switch and electrical enclosures and seals/shields/barriers, etc. Electrical components relating to

Power Developer

The previous section identified many of the nationa Product marking may bodies simplythat show and international either define regulato requirements for product safety orbut provide testing compliance with specific standards and certification to assure users that the device or increasingly more general marks are used equipment complies with the relevant to indicate compliance with all essentialstandard(s). Consequently, conformance marking of products to or legally imposed safety requirements. show this compliance is a necessary prerequisite fo CE andtheir UL marks are two of the most sale in most industrialized countries and may widely be implemented conformance marks, a legal or contractual obligation. while there are a number of other safety Product marking may simply show compliance with marks that may be applied in different specific standards but increasingly more general UL 60079: Explosive Atmospheres regions. These are described more fully marks are used to indicate compliance with all UL 60079 and its IEC and other below. essential To ease or the issue of regional legally imposed safety requirements. equivalent standards cover general differences, the Certification Body (CB)widely CE and UL marks are two of the most requirements for the construction, implemented conformance marks, scheme allows manufacturers who while there are a number of other safety marks that may be testing, and marking of electrical have been issued a CB test certificate applied in different regions. These equipment intended for use in explosive by one National Certification Body are described more fully below. To ease the issue of regional atmospheres. SuchStandards, environments obtain certification marks Power Supply Safety Agencies and (NCB) Marksto differences, the Certification Body (CB) scheme include explosive gas and combustible from other allowsparticipating manufacturersNCBs. who have been issued a CB dust atmospheres (either separately test certificate by one National Certification Body or together)(either and the standard covers (NCB) to obtain certification marks from other dust atmospheres separately or together) the temperatures and pressures under participating NCBs. and the standard covers the temperatures and which equipment shouldshould be designed pressures under which equipment be designed to operate safely,taking taking account ofof the to operate safely, account The “Conformité Européenne” or CE Mark The “Conformité Européenne” various potential ignition sources and appropriate the various potential ignition sources TheCE CE Mark was introduced nearly 30 years ago or Mark protective measures. and appropriate protective measures. for certain products sold within the European The CE Mark was introduced nearly 30 Economic Area to show conformity with legal years ago for certain products sold within Major Safety Agencies and requirements in respect of relevant safety, health the European Economic Area to show and environmental directives. The use of the CE logo Product Conformance Marks conformity with legal requirements is a manufacturer’s declaration that the product Worldwide page 9 in respect relevant safety, meets theseof requirements but thehealth logo may also The previous section identified many of the national include a four-digit code identifying the authorized and environmental directives. The The previous section identified many of and international bodies that either define regulatory thirdof party involved in assessing use the(Notified CE logoBody) is a manufacturer’s the national and international bodies that requirements for product safety or provide testing conformance. Simple CE marking is allowed under declaration that the product meets these either define regulatory requirements and certification to assure users that the device or a self-certification process if the risk level of a requirements but the logo may also for product orrelevant provide testing equipment compliessafety with the standard(s). product is considered minimal. Where a product is include a four-digit identifying the if and certification to marking assure users that to Consequently, conformance of products CE marked, it can only code carry additional markings show the this compliance is a necessary prerequisite for authorized third party (Notified Body) device or equipment complies with these relate to requirements that do not overlap, their sale most industrialized countries and may involved assessing conformance. the in relevant standard(s). Consequently, conflict orin distract from the CE marking. The be a legal or contractual obligation. European Commission’s website provides Simple CE marking is allowed undermuch conformance marking of products to extensive information about CE Marking, see amore self-certification process if the risk show this may compliance is acompliance necessarywith Product marking simply show http://ec.europa.eu/enterprise/policies/single-marketlevel of a product is considered minimal. prerequisite forincreasingly their salemore in most specific standards but general goods/cemarking/index_en.htm marksindustrialized are used to indicate compliance with all Where a product is CE marked, it can countries and may be essential or legally imposed safety requirements. only carry additional markings if these a legal or contractual obligation. CE and UL marks are two of the most widely relate to requirements that do not implemented conformance marks, while there are a number of other safety marks that may be applied in different regions. These are described more fully below. To ease the issue of regional differences, the Certification Body (CB) scheme The Underwriters Laboratories or UL Mark allows manufacturers who have been issued a CB The UL Mark indicates that either Underwriters test certificate by one National Certification Body

the illumination circuits such as lampholders are also included, as are electrical components such as LED power sources and electromechanical devices like sign rotation equipment. The standard does however exclude a long list of other components that would normally be covered by other safety standards.

Major Safety Agencies and Product Conformance Marks Worldwide

al ory

r . o for y

for certain products sold within the European Economic Area to show conformity with legal requirements in respect of relevant safety, health and environmental directives. The use of the CE logo is a manufacturer’s declaration that the product meets these requirements but the logo may also include a four-digit code identifying the authorized third party (Notified Body) involved in assessing conformance. Simple CE marking is allowed under a self-certification process if the risk level of a product is considered minimal. Where a product is CE marked, it can only carry additional markings if overlap, conflict or distract from theoverlap, CE Note also that Underwriters Laboratories these relate to requirements that do not conflict orThe distract from theCommission’s CE marking. The marking. European of Canada (ULC) is an independent European Commission’s website provides much website provides much more extensive product safety testing, certification more extensive information about CE Marking, see

TECH REPORT

information about CE Marking, see and inspection organization, which is http://ec.europa.eu/enterprise/policies/single-markethttp://ec.europa.eu/enterprise/ goods/cemarking/index_en.htm Power Supply Safety Standards, Agencies andaccredited Marks by the Standards Council policies/single-market- goods/ of Canada. It uses the above UL logos cemarking/index_en.htm accompanied by the letter “C”.

components, may be marked with the reversed UR symbol indicating a “UL Recognized” certification. In addition to certifying products to their own safety ® specifications, UL also offers an assessment process TÜV Rheinland to provide to many of the regional The Underwriters Laboratories or Thecertification Underwriters Laboratories or UL Mark TÜV Rheinland safetyUL mark schemes around the world, including Mark The TÜV Group, headquartered in Cologne, The UL Mark indicates that either Underwriters The TÜVRheinland Rheinland Group, headquartered thoseThe summarized Germany, is a leading provider of technical services UL Markbelow. that either recognized in Laboratories orindicates an equivalent nationally Cologne, Germany, is a leading worldwide. It is primarily concerned with safety testing (NRTL) has tested determined provider of technical services worldwide.and Underwriters Laboratories or of anand Note also that laboratory Underwriters Laboratories Canada quality, and operates product testing services that a product meets UL specified product safety nationally recognized testing (ULC)equivalent isthat an independent product safety testing, Itcover is primarily concerned with safety Inspection and Certification, with test marks, requirements. This certification allows a manufacturer certification and inspection organization, which is laboratory (NRTL) has tested and and quality, and operates product across a wide range of markets, including electronic to show that their product is “UL Listed” by using accredited by the Standards Council ofmeets Canada.UL It uses determined that a product testing services thatand cover Inspection components, telecoms IT equipment. the familiar UL logo. For power supplies this the above UL logos accompanied by the letter “C”. mark specified product safety requirements. would be applied to external units and DIN rail-mount and Certification, with test marks, This certification allows a manufacturer supplies as well as most consumer electronics across a wide range of markets, to show that their product is “ULisListed” including computers. Where a supply considered including electronic components, to using be a component part UL it, along electrical by the familiar logo.with Forother power

supplies this mark would be applied to external units and DIN rail-mount supplies as well as most consumer electronics including computers. Where a supply is considered to be a component part it, along with other electrical components, may be marked with the reversed UR symbol indicating a “UL Recognized” certification. In addition to certifying products to their own safety specifications, UL also offers an assessment process to provide certification to many of the regional safety mark schemes around the world, including those summarized below.

telecoms and IT equipment.

Regional Safety Marks Americas, Europe & Asia The maps in the following section highlight some of the more notable safety marking schemes but are not all-inclusive. In addition, in Europe there are other marks applicable in the Nordic countries and other central and eastern European countries such as Denmark, Switzerland, Hungary, Ukraine and Belarus. In Asia, countries including Hong Kong and India operate their own safety marks.

Power Developer

Power Supply Saf

Power Supply Safety Standards, Agencies and Marks

Regional Safety Marks Americas, Europe & Asia

Power Supply Safe

CSA Mark – Canad

The Canadian Standard The maps in the folling section highlight some of the more notable safety marking schemes but is not allscheme alongside UL c CSA Mark – Canad inclusive. In addition, in Europe there are other marks applicable in the Nordic countries and other central and in either CanadaSafet (C suffi Power Supply eastern European countries such as Denmark, Switzerland, Hungary, Ukraine and Belarus. In Asia, countriesThe Canadian Standard scheme alongside UL c including Hong Kong and India operate their own safety marks. in either Canada (C suffi

AMERICAS

CSA Mark – Canada

Americas

Canada

Mexico

Brazil

Argentina

The Canadian Standards NOM alongside Mark – Mexi scheme UL ce inThe either Canada (C suffix NOM Mark identifie Oficiales Mexicanas” ( NOM Mark – Mexic CSA Markappliances, – CanadaI electrical The NOM Mark identifie The Canadian Standards independant body auth Oficiales Mexicanas” (N scheme alongside UL cer and gas products. electrical appliances, IT NOM – Mexico in eitherMark Canada (C suffix independant body auth The identifies andNOM gas Mark products. Oficiales Mexicanas” (NO electrical appliances, IT, INMETRObody Mark – independant autho NOM Mark – Mexico and gas products. Certification of certain The NOM Markballasts identifies equipment, INMETRO Mark –anB Oficiales Mexicanas” (NO is mandatoryofincertain Brazil w Certification electrical appliances, IT, Mark. The INMETRO Ma equipment, ballasts and independant body autho indicate safety stand istomandatory in Brazil w INMETRO Mark – Br and gas products. mandated e.g. IT, audio Mark. The INMETRO Mar Certification of certain p to indicate safety stand equipment, ballasts and mandated e.g. IT, audio is mandatory in Brazil wi Mark. The INMETRO Mark INMETRO – Br Mark safety –Mark Argentin toSindicate standa Certification of IT, certain pr mandated e.g. audio/v Product certification to equipment, and under the au SArgentina Mark –ballasts Argentin is mandatory in Brazil wit conformance indicated Product certification to Mark. The INMETRO Mark Argentina under the au to indicate safety standa indicated Sconformance Mark –e.g. Argentina mandated IT, audio/v Product certification to I Argentina under the aus conformance indicated b

S page Mark12– Argentina page 11

Product certification to I Argentina page 12 under the ausp conformance indicated b page 12

page 12

TECH REPORT

fety Standards, Agencies and Marks

ety Standards, Agencies and Marks CSA Mark — Canada

ety Standards, Agencies and Marks

Europe

ds Association operates the CSA marking certification to identify products acceptable da ffixAssociation letter) and/or the USA suffix). ty Standards, Agencies and Marks ds operates the(US CSA marking

certification to identify products acceptable ffix letter) and/or the USA (US suffix).

s Association operates the CSA marking ico ertification to identify products acceptable x letter) and/orwith the USA (US suffix). es compliance Mexico’s “Normas (NOM) co safety standards for household aIT, AV and similar equipment. ANCE is an es compliance with Mexico’s “Normas shorized Association operates the CSA marking to grant NOM approval in electric NOM) safety standards for household rtification to identify products acceptable T, AV and similar equipment. ANCE is an xoletter) and/or the USA (US suffix). horized to grant NOM approval in electric s compliance with Mexico’s “Normas OM) safety standards for household AV and similar equipment. ANCE is an Brazilto grant NOM approval in electric orized o n product groups, such as medical electrical snd compliance “Normas equipmentwith usedMexico’s in hazardous locations, Brazil OM) safety standards for household with accreditation indicated by the INMETRO product groups, such as medical electrical AV may and similar equipment. ANCE is basis an ark also be used on a voluntary d equipment used in hazardous locations, orized to grant NOM approval in electric dards complianceindicated for products thatINMETRO are not with by the razilaccreditation o/visual equipment and home appliances. rk may also be used on a voluntary basis product groups, such medicalthat electrical dards compliance foras products are not equipment used in hazardous locations, o/visual equipment and home appliances. ith accreditation indicated by the INMETRO k may also be used on a voluntary basis razilcompliance for products that are not na ards roduct groups, such medical electrical visual equipment andashome appliances. o IEC-based standards is mandatory in equipment used in hazardous locations, uspices of its standards body IRAM with na thby accreditation indicated by the INMETRO the S Mark. odIEC-based standards is mandatory in k may also be used on a voluntary basis uspices of its standards body IRAM with ards compliance for products that are not d by the S Mark. avisual equipment and home appliances. IEC-based standards is mandatory in spices of its standards body IRAM with by the S Mark.

IEC-based standards is mandatory in pices of its standards body IRAM with by the S Mark.

The Canadian Standards Association operates the CSA marking scheme alongside UL certification to identify products acceptable in either Canada (C suffix letter) and/or the USA (US suffix).

NOM Mark — Mexico The NOM Mark identifies compliance with Mexico’s “Normas Oficiales Norway Mexicanas” (NOM) safety standards for household electrical appliances, IT, AV and similar equipment. ANCE is an independent body Russia authorized to grant NOM approval in electric and gas products.

INMETRO Mark — Brazil Certification of certain product groups, such as medical electrical equipment, ballasts and equipment used in hazardous locations, is mandatory in Brazil with accreditation indicated by the INMETRO Mark. Germany The INMETRO Mark may also be used on a voluntary basis to indicate safety standards compliance for products that are not mandated, e.g. IT, audio/visual equipment, and home appliances.

S Mark — Argentina Product certification to IEC-based standards is mandatory in Argentina under the auspices of its standards body IRAM with conformance indicated by the S Mark.

Power Developer

Nemko is uct safety Power Supply Safety Standards, Agencies anddirect Marks ser extends t Power Supply Safety Standards, Agencies and Marks and gas in Power Supply Safety Standards, Agencies and Marks or certifie safety reg

EUROPE

ENEC Mark - Europe Power Supply Safety Standards, Agencies and Marks The ENEC Mark Mark is-simply the mark used to denote compliance with ENEC Europe GOST-R the European Norm (EN) standards for all electrical product sectors,

Europe

The ENEC Mark is simply the mark used to denote compliance with asthe tested by approved independent testing worldwide. VNIIS is th European Norm (EN) standards for alllaboratories electrical product sectors, GOST-R s as tested by approved independent testing laboratories worldwide. Customs regulated ance with Nemko Mark - Norway products Nemko is anMark organization similar to TUV or UL that offers prodNemko - Norway Powe uct safetyistesting and certification standards. Its Norway Nemko an organization similar to to worldwide TUV or UL that offers proddirect services coverand IT/AV, householdtoand telecoms products Its but uct safety testing certification worldwide standards. extends to other sectors such as medical equipment, and the direct services cover IT/AV, household and telecoms productsoilbut GS Mark and gas industry. marksuch itselfas signifies Nemko has Power extends to otherThe sectors medicalthat equipment, andtested the oil S Norway orand certified the product according to national standards official Germany’s gas industry. The mark itself signifies that Nemko has tested safety regulations in Norway. Sicherheit or certified the product according Russia to national standards official Equipmen safety regulations in Norway. Produktisi VDE M andThe consu VD institution Russia based GOST-R Certification and PCT Mark – Russia operated producb VNIIS is the agency that provides for VDE the Mar GOST-R Certification andcertification PCT Markservices – Russia DIN,standa EN, IE GOST-R system that operates in the Russian Federation and The VDE Te VNIIS is the agency that provides certification services for the and co Customs is mandatory an extensive range based inde GOST-RUnion. systemGOST-R that operates in the for Russian Federation andof applica regulated products while the PCT Mark, used to indicate complipage products. Customs Union. GOST-R is mandatory for an extensive range of14 ance with Russian standards, recommended forindicate regulated standards, regulated products while theisPCT Mark, used to compliproducts where GOST-R is not mandated. and confirm ance with Russian standards, is recommended for regulated applicable products where GOST-R is not mandated. Germany

BSI K

The Br

GS Mark and DIN Mark – Germany/EU nation Germany Germany’s TUV standards agency operates the GS Mark (Geprüfte GS Mark and DIN Mark – Germany/EU BSIstanda Kite

repres Sicherheit = tested safety) toagency show conformity with Germany’s TUV standards operates the GSGerman’s Mark (Geprüfte The British volunta Equipment Product Safety (GPSG = GeräteSicherheitand = tested safety) toAct show conformity withund German’s national st of trus Produktisicherheitgesetz). The GSAct Mark assures commercial buyers Equipment and Product Safety (GPSG = Geräteund standards approp and consumers the product has tested by ancommercial authorized buyers Produktisicherheitgesetz). Thebeen GS Mark assures representi for qua institution such asthe TUVproduct Rheinland. The DIN Markbyisan another scheme and consumers has been tested authorized voluntary c operated by TUV certifyingThe component with institution suchRheinland as TUV Rheinland. DIN Markcompliance is another of scheme trust, th DIN, EN, IECby and ISORheinland product safety UK standards. operated TUV certifying component compliance with appropriat DIN, EN, IEC and ISO product safety standards. for quality, page 14 page 14 page 13

page 13

an organization similar to TUV or UL that offers prody testing and certification to worldwide standards. Its rvices cover IT/AV, household and telecoms products but to s other sectors such as medical equipment, and the oil ndustry. The mark itself signifies that Nemko has tested ed the product according to national standards official gulations in Norway. ENEC Mark — Europe

The ENEC Mark is simply the mark used to denote compliance with the European Norm (EN) standards R Certification and PCT Mark – Russiafor all electrical product he agency that provides certification services for the sectors, as tested by system that operates in the Russian Federation approved and independent Union. GOST-R is mandatory for an extensive range of testing laboratories worldwide. d products while the PCT Mark, used to indicate complih Russian standards, is recommended for regulated where GOST-R is not mandated.

AsiaPac

Nemko Mark — Norway

er Supply Safety Standards, Agencies and Marks

TECH REPORT GOST-R Certification and PCT Mark — Russia VNIIS is the agency that provides certification services for the GOST-R system that operates in the Russian Federation and Customs Union. GOST-R is mandatory for an extensive range of regulated products, while the Japan PCT Mark, used to indicate compliance with Russian standards, is Japan recommended for regulated products where GOST-R is not mandated.

Nemko is an organization similar to TÜV or UL that offers product safety Korea testing and certification to worldwide k and DIN Mark – Germany/EU Supply Safety Standards, Agencies standards. and MarksIts direct s TUV standards agency operates the GS Mark (Geprüfte services cover IT/AV, t = tested safety) to show conformity with German’s Korea nt and Product Safety Act (GPSG = Geräte- undhousehold and telecoms Taiwan icherheitgesetz). The GS Mark assures commercial buyersbut extends Mark – Germany products umers the product has been tested by an authorized toGermanother sectors such as DE Testing and Certification Institute is another nindependent such as TUV testing Rheinland. The medical DIN Mark isequipment, another organization for electric andscheme electronic and the oil and Taiwan by TUV compliance with cts. TheRheinland VDE Markcertifying indicatescomponent conformity with the VDE gas industry. The mark itself signifies rk – Germany China EC and ISO product safety standards. ards, European or internationally harmonized standards that Nemko has tested or certified the esting and Certification is another Germanonfirms compliance withInstitute protective requirements of the product according to national standards ependent testing organization for electric and electronic able EC Directive(s). official safety regulations in Norway. The VDE Mark indicates conformity with the VDE China Singapore , European or internationally harmonized standards ms compliance with protective requirements of the EC Directive(s).

Kitemark - UK

GS Mark and DIN Mark — Germany/EU

ritish Standards Institution (BSI) was the world’s first Germany’s TÜV standards agency nal standards body and continues to be a leading global operates GS Mark (Geprüfte ards maker. BSI is also the UK’s Nationalthe Standards Body, emark - UK Sicherheit = tested to show senting UK interests worldwide. The BSI Kitemark is safety) a hary Standards Institution (BSI) was the world’s first with certification mark, globally recognized as a conformity symbol tandards bodyaand continues to bemeets a leading global and st, that shows product or service applicable German’s Equipment spriate maker. BSI is European, also the UK’s National Standards Body, British, International and otherand standards Product Safety ing UK interests worldwide.and Thetrust. BSI Kitemark is a ality, safety, performance Act (GPSG = Gerätecertification mark, globally recognized as a symbol und Produktisicherheitgesetz). The hat shows a product or service meets applicable and te British, European, International and other standards GS Mark assures commercial buyers y, safety, performance and trust. and consumers the product has been

tested by an authorized institution such as TÜV Rheinland certifying component compliance with DIN, EN, IEC, and ISO product safety standards.

VDE Mark — Germany The VDE Testing and Certification Institute is another German-based independent testing organization for electric and electronic products. The VDE Mark indicates conformity with the VDE standards, European or internationally harmonized standards and confirms compliance with protective requirements of the applicable EC Directive(s).

Singapore

BSI Kitemark — UK The British Standards Institution (BSI) was the world’s first national standards body and continues to be a leading global standards maker. BSI Australia is also the UK’s National Standards Body, representing UK interests worldwide. The Australia BSI Kitemark is a voluntary certification mark, globally recognized as a symbol of trust, that shows a product or service meets applicable and appropriate British, European, International and other standards for quality, safety, performance, and trust.

Power Developer

EK Mark EK Mark – Power Supply Safety Standards, Agencies andKorea’s Marks EK Standards Korea’s EK M EK Mark – Standards, Korea Power Supply Safety Agencies and Mar

with the (M E Standards Korea’s EK Mark is administered by its Agency for Tec with the Elec Standards (MOCIE) to show compliance for mandate with the Electrical Appliances and Materials Safety C

ASIA PAC

BSMI M DENAN PSE Mark – Japan BSMI Mar The BSMI Power Supply Safety Standards, Agencies andMark Marks TheDENAN PSE is used to show compliance with Japan’s Electrical TheCertificati BSMI (B PSEBSMI MarkMark – Japan – Taiwan Appliance and Material Safety Law (DENAN) as applied to various

AsiaPac

products i Certification The PSE MarkThe is used to(Bureau show compliance withMetrology Japan’s Electrical BSMI of Standards, and Insp classes of product and equipment. products in T Appliance andCertification Material Safety Law (DENAN) as applied to and various is the approval scheme for ITE aud classes of product and equipment. products in Taiwan.

EK Mark – Korea

CCC Ma CCC TheMark CCCSu ( Power

Korea’s EK Mark administered by its Agency for Technology and (Ch complianc The CCC EK Mark – isKorea Japan CCC Mark – China Standards (MOCIE) to show compliance for mandated products names im compliance Korea’s EK Mark isCCC administered by its Agency for Technology and (China Certificate) Mark indic with the ElectricalThe Appliances andCompulsory Materials Safety Control Law. commerc names impli Standards (MOCIE) to showwith compliance for mandated products compliance Chinese laws and regulations and commercial with the Electrical Appliances and Materials Safety Control Law. names implies, is compulsory for any product used commercial purposes in China.

Korea

BSMI Mark – Taiwan

RCM PSB Tick ‘SA TheBSMI BSMI (Bureau of Standards, Metrology and Inspection) PSB ‘SAFE Australia h Singapore Mark – Taiwan Certification is the approval scheme for ITE and audio/ video Australia, Board (PSc Singapore’s PSBof‘SAFETY’ – Singapore The BSMI (Bureau Standards,Mark Metrology and Inspection) products in Taiwan.

Taiwan Electrotech marked w Board (PSB) Certification isSingapore’s the approval scheme for ITEthe andProductivity audio/ video safety authority, and St electronic marked with products in Taiwan. Board (PSB), requires all controlled goods to be ind for safety. marked with the SAFETY Mark. consolidate page (effe 17 marks CCC Mark – China page 17 China are allowed TheCCC CCC (China Compulsory Certificate) Mark indicates 17 Mark –page China compliance with Chinese laws and regulations and, as its The CCC (China Compulsory Certificate) Mark indicates names implies, is compulsory for any product used for compliance with ChineseSingapore laws and regulations and, as its commercial purposes in China. names implies, is compulsory for any product used for commercial purposes in China.

Summ

Despite eff bring abou PSB ‘SAFETY’ Mark – Singapore equipment Singapore’s safety authority, Productivity and Standards PSB ‘SAFETY’ Mark –the Singapore different re Board (PSB), requires all controlled goods to be individually Singapore’s safety authority, the Productivity and Standards that may n marked with the SAFETY Mark. Board (PSB), requires all controlled goods to be individually requiremen marked with the SAFETY Mark. will be sold Australia application page 17 overview of certainly no page 17

CUI follows the highest approved t providing q power tech page 16

For furthe www.cui.c

k – Korea – Korea sK Mark is administered by its Agency for Technology and

s (MOCIE) to show compliance for mandated products Mark is administered by its Agency for Technology and rks Electrical and Materials Safety Control Law. MOCIE) toAppliances show compliance for mandated products chnology and ctrical Appliances and Materials Safety Control Law. ed products Control Law.

DENAN PSE Mark — Japan

The PSE Mark is used to show compliance Mark – Taiwan with Japan’s Electrical rk – Taiwan (Bureau of Standards, Metrology and Inspection)

PS EPS E product and equipment. classes of

and Material ion is the approval scheme for ITE audio/Appliance video Bureau of Standards, Metrology andand Inspection) Safety Law (DENAN) ninisTaiwan. the approval scheme for ITE and audio/ video pection) Taiwan. as applied to various dio/ video

EK Mark — Korea

ark – China Korea’s EK Mark is administered by its k(China – China Compulsory Certificate) Mark indicates upply Safety Standards, Agencies and Agency Marks for Technology

ce with Chinese laws and regulations and, as its hina Compulsory Certificate) Mark indicates and Standards (MOCIE) mplies, is compulsory forregulations any product used with Chinese laws and and, asfor its cates to show compliance cial in China. ies,purposes is compulsory for any product used for d, as its for mandated purposes in China. d for

products with the Electrical Appliances and Materials Safety Control Law.

k Mark– Australia AFETY’ Mark – Singapore ETY’ Mark – Singapore has a national standards body, Standards PSB ‘SAFETY’ Mark — Singapore e’s safety authority, the Productivity and Standards

covering many industry sectors including SB), requires alldifferent controlled goods to beStandards individually safety authority, the Productivity and and embraces electrical/ with the SAFETY Mark.which ),hnology requires all Energy, controlled goods to be individually tandards appliances with relevant standards hequipment the SAFETYand Mark. dividually Australia’s Regulatory Compliance Mark (RCM) now es the previously separate C-Tick, A-Tick and RCM Singapore’s authority, the ective from March 2013, although existingsafety suppliers d a 3-year transition period).Productivity and Standards Board

mary

(PSB), requires all controlled goods to be individually marked with the SAFETY Mark.

Summary

fforts within Europe, North Americaefforts and elsewhere Despite withinto Europe, North ut harmonization of safety standards for electrical America and elsewhere to bring about t including power supplies, there are still very many harmonization of safety standards egulations, testing and certification procedures electrical equipment including need to be taken accountfor of in order to meet legislative power supplies, there are still very nts in the various territories where such equipment many testing and d. Understanding all of these is adifferent challengeregulations, and this n note, while it tries to present a fairly comprehensive certification procedures that may need f the various standards, to agencies and account safety marks, be taken of inisorder to meet ot a definitive guide.

legislative requirements in the various territories where such s best practices to ensure its power supplies meet equipment will t levels of safety and performance, offering products be sold. Understanding all of these is to standards such as UL,aENEC, TUV and GS this whileapplication also challenge and note, quality solutions that utilize the latest in efficient green hnology.

er information on CUI’s power supplies visit com.

TECH REPORT BSMI Mark — Taiwan The BSMI (Bureau of Standards, Metrology, and Inspection) Certification is the approval scheme for ITE and audio/ video products in Taiwan.

CCC Mark — China The CCC (China Compulsory Certificate) Mark indicates compliance with Chinese laws and regulations and, as its name implies, is compulsory for any product used for commercial purposes in China.

RCM Tick Mark — Australia Australia has a national standards body, Standards Australia, covering many different industry sectors, including Electrotechnology and Energy, which embraces electrical/electronic equipment and appliances with relevant standards for safety. Australia’s Regulatory Compliance Mark (RCM) now consolidates the previously separate C-Tick, A-Tick, and RCM marks (effective from March 2013, although existing suppliers are allowed a 3-year transition period).

while it tries to present a fairly comprehensive overview of the various standards, agencies and safety marks, is certainly not a definitive guide. CUI follows best practices to ensure its power supplies meet the highest levels of safety and performance, offering products approved to standards such as UL, ENEC, TUV and GS while also providing quality solutions that utilize the latest in efficient green power technology. For further information on CUI’s power supplies visit: http://www.cui.com www.cui.com

Power Developer

DC/DC

Book of

KNOWLEDGE Chapter 1 By Steve Roberts Technical Director for RECOM

TECH SERIES

Intro to Power Regulation RECOMÂ´s DC/DC Book of Knowledge is a detailed introduction to the various DC/DC converter topologies, feedback loops (analogue and digital), test and measurement, protection, filtering, safety, reliability, constant current drivers and DC/DC applications. The level is necessarily technical, but readable for engineers, designers and students.

Power Developer Intro to Power Regulation Modern AC/DC and DC/DC converters are designed to provide efficient power conversion to deliver a controlled, safe and well-regulated DC power supply for a variety of electronic instruments, devices and systems. Itâ&#x20AC;&#x2122;s not all too long ago that a transformer, rectifier and linear regulator was the main technology in power conversion, but just as the LED is slowly replacing the light bulb, so is the DC/DC converter gradually edging out the linear regulator and the primary-side switching controller is replacing the simple 50Hz mains transformer. In the past decade there has been immense technical progress in the development of switching regulators to allow the benefits of new circuits, components, and materials that simply did not exist before. This progress has made it possible to increase the performance and to improve the thermal behavior, while simultaneously substantially reducing the size, weight and cost of power supplies. Consequently, switching regulators are used today in large numbers and are the standard technology in both DC/ DC and AC/DC power conversion.

Linear Regulations Linear voltage regulators deliver a stable output voltage from a more or less stable input voltage source. In normal operation, even if the

input voltage fluctuates rapidly, the output voltage remains stable. This means they can also very effectively filter out input ripple, not only at the fundamental frequency, but also as far as the fifth or tenth harmonic. The limitation is only the reaction speed of the internal error amplifier feedback circuit. Most linear regulators have a closed loop control. Fig. 1.1 illustrates this type of voltage regulation. The pass transistor is the regulatory element, effectively a variable resistor that limits the current flowing from input to output. The resistor divider chain R1/R2 is chosen so that at the required output voltage, the divided down voltage at the error amp inverting input is the same as the VREF voltage at the non-inverting input. The error amplifier controls its output in such a way that the voltage difference between its inputs is always zero. If the voltage at the output increases due to a reduction in the load or an increased input voltage, the voltage at the inverting input of the error amplifier rises higher than VREF voltage and the output of the error amplifier goes negative, so reducing the drive to the pass transistor and reducing the output voltage. Alternatively, if the load increases or the input voltage drops, the voltage at the

1.1 Linear Regulators

TECH SERIES

Linear voltage regulators deliver a stable output voltage from a more or less stable input voltage source. In normal operation, even if the input voltage fluctuates rapidly, the output voltage remains stable. This means they can also very effectively filter out input ripple, not only at the fundamental frequency, but also as far as the fifth or tenth harmonic. The limitation is only the reaction speed of the internal error amplifier feedback circuit.

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Fig. 1.1: 3-Pin Linear Regulator Block Diagram and Pinout Figure 3-Pin regulators Linear Regulator Block Diagramloop and Pinout. Most1.1.linear have a closed control.

Fig. 1.1 illustrates this type of voltage regulation. The pass transistor is the regulatory element, effectively a variable resistor that limits the current flowing from input to output. The resistor divider chain R1/R2 is inverting sinksat below VREF Fig. 1.1 simplified 3-pindown regulator block at the error amp choseninput so that the the required outputThe voltage, the divided voltage voltage and the drive to the transistor is diagram does not show the short circuit inverting input is the same as the VREF voltage at the non-inverting input. The error increased to raise the output voltage the output is shorted to ground, amplifier controls its output intosuch aprotection. way thatIfthe voltage difference between its inputs compensate. Thus the same feedback the transistor would be turned hard on and is always zero. loop regulates for both input voltage variations (line regulation) and changes in load (load regulation). It need not be specially emphasized that the reference voltage must be very stable and have an excellent temperature coefficient to give a stable and accurate output voltage, but with a good PCB layout an output voltage ripple/noise value of less than 50ÂľVp-p is easily possible.

a very high current would flow from input to output, so a second internal circuit is needed to limit the current (Fig 1.2). The current limiting uses the voltage drop across the sense resistor, RS to monitor the ouput current. When the current is high enough so that the voltage exceeds 0.7V, Q2 starts to conduct to â&#x20AC;&#x153;stealâ&#x20AC;? current away from Q1, thus reducing the drive and limiting the output current, thus ILIMIT = 0.7V/RS.

If the voltage at the output increases due to a reduction in the load or an increa 1. voltage, the voltage at the inverting input of the error amplifier rises higher voltage and the output of the error amplifier goes negative, so reducing theLin d pass transistor and reducing the output voltage. Alternatively, if the load increa dis vo input voltage drops, the voltage at the inverting input sinks below the V REF As mentioned before, if the voltage The current limit needs to be set well the drive to above the transistor increased to raise the between output input voltage to compens difference and output is the maximum is current that required headroom (typically the same feedback for both below inputthe voltage variations (line regula would flowsloop during regulates normal operation. then the regulation loop can no that the the limit is 150% - 200% changes in Typically load (load regulation). It need not2V),be specially emphasized longer function properly. A common higher than the rated current. As the voltage must be very stable and have an application excellent temperature coefficient problem occurs when a regulator is not disabled during a short stable and circuit, accurate output voltage, a AC good PCB rectified input has a highlayout voltage an outpu it is in constant overload. Some but with ripple because the smoothing capacitor ripple/noiselow value of less thansimply 50ÂľVp-p is easily possible. cost linear regulators rely

Power Developer

is too small (Fig. 1.3). If the input voltage on the thermal protection circuit to drops below the drop out voltage on each shut down the pass transistor before The Fig. 1.1 simplified 3-pin regulator block diagram does not show the sh half cycle, then the regulated output it burns out as the â&#x20AC;&#x153;short circuit protection. Ifprotection.â&#x20AC;? the output is shorted transistor willthe show periodic dipswould at doublebe theturned ha This may protect theto ground, mains frequency. momentary a very high linear current would flow frompower input to output, so a These second internal circuit regulator, but the primary dips will not show on a multimeter supply may overheat andThe fail ifcurrent it is to limit the current (Fig 1.2). limiting uses theupvoltage drop across P which just measures the average output not dimensioned to deliver the short the current is high enough s resistor, RS to monitor the ouput current. When voltage, but can nevertheless cause circuit current during the time it takes startsitself to off. conduct to â&#x20AC;&#x153;stealâ&#x20AC;? current away from voltage exceeds 0.7V, Qto2 switch â&#x20AC;&#x153;unexplainedâ&#x20AC;? circuit problems. This Q1, thus for the regulator As effect can be = eliminated 0.7V/RS.by either using the drive and limiting the output current, thus ILIMIT re larger smoothing capacitors or increasing Other Properties of the the turns of the transformer pr The currentLinear limitRegulator needs to be set well above theratio maximum current that wo â&#x20AC;&#x201D;both rather expensive options. Linear regulators have a number of during normal operation. Typically the limit is 150% - 200% higher than the rate Invoc advantages on the one hand, but also dr As the regulator is disadvantages not disabled circuit, it is in constant overlo Switching Regulator have some that during require a short out to linear regulators, which to shut pe special care in their application low cost linear regulators simply and relyuse. on theIn contrast thermal protection circuit and dump excess power as heat in order pass transistor before it burns out as the â&#x20AC;&#x153;short circuit protectionâ&#x20AC;?. This may ofap e to limit the output voltage, switching

1.2

linear regulator, but the primary power supply may overheat and failcap if ca dimensioned to deliver the short circuit current during the time it takes for load the sm to switch itself off. sim ex Â?

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Figure 1.2. Linear regulator with current limiting (â&#x20AC;&#x153;short circuit protectionâ&#x20AC;?)

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Th am sig tra m dr Fig. 1.2: Linear regulator with current limiting (â&#x20AC;&#x153;short circuit prote dr To sta reg Practical Tip ofbe c

ased input .1.2 Other Properties of the Linear Regulator than VREF TECH SERIES drive to the near regulators have a number of advantages on the one hand, but also have some ases or the that require special care in their application and use. sadvantages oltage and sate. Thus Input Voltage to Linear Regulator ation) and reference 7805 t to give a L LOAD 100ÂľF ut voltage 7V

Output Voltage from Linear Regulator

hort circuit ard on and Fig. 1.3: Drop Out Problem with Linear Regulator. is needed regulators exploit the energy-storing complex regulation technique is needed Figure 1.3. the sense properties of inductive and capacitive than that for the linear regulator. The Practical Drop Out so thatcomponents the to transfer power in discrete most common type of control is PWM Problem with Tip s reducing energy packets. The packets of energy (Pulse Width Modulation), where the Linear Regulator s mentioned before, the voltage difference between input are stored either in the if magnetic field amount of energy transferred fromand output is below the of an inductor or in the electric field2V), of inputthe to output is modulated by a can no longer function equired headroom (typically then regulation loop a capacitor. The switching controller problem variable width pulse withaa rectified fixed time AC input has a high 2 Switching Regulator roperly. A common application occurs when ould flows ensures that only the energy actually interval. The duty ratio of the PWM, oltage ripple because the smoothing capacitor ispower too small (Fig.in1.3). thelimit input ed current. (the time required by the load is transferred in Ă¤, isexcess the ratio of on-time t heat contrast to linear regulators, which dump as orderIf to thevoltage rops below the drop out voltage each half cycle, the regulated will show oad. Some during which energythen is drawn from each packet, so this topology is very on tput voltage, switching regulators exploit the energy-storing properties of output inductive the source) to the momentary period T (the inverse efficient. Fig.double 1.6 shows the the simplified eriodic dips at frequency. dips will show up on td down the components capacitive tomains transfer power in These discrete energy packets. Thenot packets of the switching frequency Ć&#x2019; ). structure of a switching regulator. protect thestored multimeter which just inmeasures thefield average output voltage, but canfield nevertheless energy are either the magnetic of an inductor or in the electric of a f it isâ&#x20AC;&#x153;unexplainedâ&#x20AC;? not ause circuit problems. This effect canenergy be eliminated by eitherby using pacitor. switching controller ensures that only the actually required the larger For many switching regulators, the ToThe transfer the energy from input to emoothing regulated voltage is directly outputcapacitors in controllable a more orpacket, increasing turnsoutput ofefficient. the transformer â&#x20AC;&#x201C; both dregulator is transferred in eachamounts, so thisthe topology isratio very Fig. 1.6 shows the rather mplified structure of a switching regulator. xpensive options. on

OSC

.1.3 LDO Regulators

he bipolar pass transistor used in the standard linear regulator is used as a current mplifier. The drive current from the output amplifier is multiplied by the small of the error Â? Â?Â? 1.6. Â gnal current gain of the transistor (HFE) to deliver the load current. The HFigure of a power FE Block Diagram Â? Â ansistor is quite low, typically 20-50, so often a Darlington configurationofis used with a Swithing Regulator.current multiple increase effective current gain and reduce the output Fig.transistors 1.6: Blockto Diagram of the a Switching Regulator rawn from the error amplifier. The disadvantage of a Darlington transistor is that the ectionâ&#x20AC;?) rop-out increases by VtoBEoutput for each stage, so the typical adrop voltage for a transfervoltage the energy from input in controllable amounts, moreout complex andardtechnique linear regulator uses NPN type Darlington gulation is neededwhich than that for a thePNP lineartransistor regulator. to Thedrive mostan common control is PWM (Pulse Width Modulation), where the amount of energy transferred 25 ecomes:

Power Developer PRACTICAL TIP The difference between input and output voltage is dropped by the pass transistor. If, for example, the input voltage is 12V (say from a car battery) and the regulated output voltage is 5V, then 7V has to be dropped by the transistor. This means more power is dissipated in the regulator than is actually delivered to the load (see also the discussion of efficiency calculation in the next section). This is why most linear regulators need a heat sink. Obviously, if the input voltage drops below the output voltage, the linear regulator cannot compensate and the output voltage will follow the input voltage down. However if the input voltage drops too low, the internal power supply to the error amplifier and VREF will be compromised and output may become unstable or start to oscillate. Linear regulators also perform poorly in stand-by. Even if no load is applied, a typical 78xx series regulator still needs around 5mA to power the error amp and reference voltage circuits. If the input voltage is 24V, this quiescent current means a no load consumption of 120mW.

PRACTICAL TIP The advantages of linear regulators are low cost, good control characteristics, low noise, low emissions and excellent transient response. The disadvantages are high quiescent consumption, only single outputs and extremely low efficiency for large input/output voltage differences.

proportional to the duty cycle of the PWM. The control loop uses the “largesignal” duty cycle to control the powerswitching element. In contrast, the linear regulator uses the “small-signal” servo loop to limit the current through the pass transistor. PWM control is much more efficient than linear control, because the main losses only occur during each change-of-state of the switch rather than continuously. FETs that are full on or full off dissipate little power.

Switching Frequency and Inductor Size The size of the switching and storage elements of a switching regulator is inversely proportional to the switching frequency used. The power that can be stored in an inductor is:

Equation 1.4. Stored Power in an Inductor The amount of power stored in the inductor is proportional to the frequency. For a fixed amount of power storage, the size of the inductance, L, can be halved if the frequency is doubled, for example. In capacitive elements of the equation for the stored power is as follows:

Equation 1.5. Stored Power in a Capacitor

TECH SERIES Here again, the capacitor size can be reduced by increasing the frequency without compromising the power storage. These reductions in physical size are significant for both the manufacturer as well as the customer, because thereby the switching regulators require less packaging and also take up less board space. However, the reduced space requirement goes hand in hand with the increase in RF noise emissions as the switching frequency is increased, so there is an EMC trade-off that limits the highest practical switching frequency to around 500kHz (some very small designs can work at 1MHz or higher, but these need very careful PCB layout and EMC shielding).

Switching Regulator Topologies

b. Isolated converters, in which the energy is transferred via mutually coupled magnetic components (transformers), wherein the coupling between the supply and the load is achieved solely via an electromagnetic field, thereby permitting galvanic isolation between input and output. So far, Chapter 1 of the Book of Knowledge has covered linear and switching regulators as well as in-depth look at their topologies and characteristics. The chapter goes on to cover boost converter applications, synchronous and asynchronous conversion, PWM-regulation techniques, and much more. To read the chapter in its entirety, visit: http://www.recom-power.com/ downloads/book-of-knowledge.

The term topology refers to the different forms of switching and energy storage element combinations that are possible for the transmission, control and regulation of an output voltage or current from an input voltage source. The many different topologies for switching regulators can be divided into two main groups: a. Non-isolated converters, in which the input source and the output load share a common current path during operation

Power Developer

Design Considerations for Low-Power Embedded Systems: Part 2 By Rahul Raj Sharma and Tushar Rastogi

In the first part of this series, we covered general design considerations for creating a low-power system. In this part, we will cover examples of low-power applications, trade-offs between low-power consumption and system performance, and offer an example of a low-power system design utilizing the techniques discussed in Part 1.

Low Power Applications 1.

Ultra Low Power Remote Requirements for this kind of system include the ability to stay in sleep mode for a good part of the day. The system needs to be able to wake up in case of user inputs, perform some action (i.e., send some commands), then return to sleep. Minimizing how long this takes will maximum battery operating life.

2. Heart Rate Monitor Requirements for this kind of system include the ability to automatically wake the CPU at regular intervals.

The interval depends on the operating condition the device is in â&#x20AC;&#x201C; i.e., whether it is connected to a human body or not. If it is strapped to a body, it will read the heart rate at shorter intervals. If not, it will wake at longer intervals to just check if it attached to a body and needs to change its operating status. 3. Wireless Sensing Systems Requirements for this kind of systems include the ability to continuously monitor the device environment and send the data to the central system for further processing and analysis of data. The system should be able to minimize power loss during sensor interactions and communication with the central system. 4. Mechanical Button Replacement (MBR) MBRs are used to replace mechanical buttons with capacitive touch buttons. The system needs to be able to sample the touch button every 50 â&#x20AC;&#x201C; 100ms and then go to sleep to conserve power.

TECH SERIES

Trade-off Between Low Power and Performance Most low-power systems are designed to save power. As discussed in Part 1 of this series, we can reduce dynamic power by running the system at lower clock speeds. However, this change reduces the system’s ability to respond to inputs. For some applications, this time gap can sometime be hazardous. To bridge this gap, it should be determined how much response delay can be tolerated, and the system clock should be set so that that the actual delay is not greater than the desired value. This will improve system responsiveness at the expense of power consumption.

The wireless transmitter operates using a coil cell battery and toggles the power state (LOCK / OPEN) of the receiver. When a switch (SW) is pressed for the first two seconds, it displays the current state and then pings the receiver with the opposite state after a two second timeout. If the receiver sends back an acknowledgement, then it updates the status in Flash (used as EEPROM). The power consumption of the system developed here is so low that the operating life of the system is limited by cell’s shelf life rather than the power consumed by the system. Let’s go through the design of the transmitter section of this system:

Transmitter:

Example of low power embedded system design

This block transmits a lock state to the receiving end and waits for a response to update the Flash with a new state.

This section will discuss how to design a low-power-consuming duplex communication system using a PSoC processor from Cypress and utilizing its low power modes. The basic function of this system is a remote to control other devices. This example demonstrates a low-power consuming, coin-cell operated transmitter built with a PSoC 4 and a lowpower, low-cost 2.4GHz transceiver.

The whole system remains switched OFF when it is not in use. When a user presses the switch on the transmitter, power to the whole system is turned ON. After system initialization, the PSoC 4 reads it own Flash row to get the current lock-state and updates the segment LCD with the lock-state. Next, the CPU configures the watchdog timer to wake up the system after two seconds and then drops into deep-sleep power mode.

Power Developer The two seconds of deep-sleep time is used to provide two features to the end-user: 1.

Filtering out unintentional user presses. If the user releases the switch before the system wakes up (two seconds), then the system returns to low power mode without changing the current state. The delay is used as a feature to allow the user to check the current state without toggling the state. To do this, the user can briefly press the switch and let it go after seeing the previous state in the display.

Cypress provides pre-tested, production ready easy to use application programming interface (APIs) to make it easier to program a PSoC. But however when an API is called then we need multiple clock cycles to store the current state in stack then execute the API and then come out of the API. When you are looking to cut down on the power then every single clock transition counts and to reduce them we need to do direct register writes instead of calling APIs to do that. Cypress also provides you with easy to use macros for register writes.

TECH SERIES SPI_TX_FIFO_WR_REG = WRITE | RX_ADDR_P0; SPI_TX_FIFO_WR_REG = 0x12; SPI_TX_FIFO_WR_REG = 0x34; SPI_TX_FIFO_WR_REG = 0x56; SPI_TX_FIFO_WR_REG = 0x78; SPI_TX_FIFO_WR_REG = 0x9A; WFI; SPI_TX_FIFO_WR_REG = ACTIVATE; SPI_TX_FIFO_WR_REG = 0x73; WFI;

In this code, instead of using the “SPI_SpiUartWriteTxData” API provided with the PSoC Creator, SCB FIFOs were directly updated to transmit data. After loading the FIFOs with the required values, the “WFI” assembly function was called to put the PSoC 4 into sleep mode. Once the SPI completes transmission of all the data stored in the FIFO, it generates an interrupt which wakes the PSoC 4 and repeats the process. Similarly for the LCD display, PSoC Creator provides APIs to simplify programming. To optimize the system for low power, these APIs are replaced with the required register writes. Using these register writes reduces the number of system cycles and hence power consumption:

CY_SET_REG32(CYREG_LCD_DATA02, 0x10000000); CY_SET_REG32(CYREG_LCD_DATA03, 0x10000011);

Power Developer Battery Life: We tested the battery life of this battery by powering the whole system with four 2200 uF capacitors connected in parallel. As we know Here

Q = CV

…(i)

C = 2200 x 10 -6 F x 4 = 8800 x 10 -6 V = 3V Q = 8800 x 10 -6 x 3 = 26.4 mC

Transmitter pings 50 times from fully charged bulk capacitors. The system works till 1.65 V. Hence charge used by the system; Qused = 8800 x 10 -6 x (3 – 1.65) = 11.88mC

…(ii)

Qper ping = Qused / Number of Pings = 11.88mC / 50 = 236µC

…(iii)

Rating of a normal coin cell battery is 200mA Hr As we know

Rahul Raj Sharma is an Application Engineer working in Cypress Semiconductors on USB devices. He has worked

Q=Ixt

on PSoC applications and

Hence Qbatt = 200 x 10-3 x 1Hr = 200 x 10-3 x 3600s = 720C We can never use the complete energy of a battery due to various physical limitations, let’s assume we can use 50% of the total energy stored in battery.

loves to do analog and mixed signal designs. He can be reached at

rrsh@cypress.com rrsh@cypress.com. Tushar Rastogi worked as

Then, Qbatt-available = 720 x 0.5 = 360C

Applications Engineer in

No of pings a battery can deliver = Qbatt-available / Qper ping = 360 / (236 x 10 -6) = 1.525 x 106 Battery life assuming 20 pings per day

ABOUT THE AUTHORS

= 1.525 x 106 / 20 = 76.2 x 103 Days = 76.2 x 103 / 365 Years = 208 Years (Not possible)

Cypress Semiconductors. He has worked on PSoC based applications since 2012. His responsibilities include PSoC firmware programming, application development, technical support to customers with programming, and

Practical effective battery time of the whole system is limited by the shelf life of the cell rather than power consumed by the system itself.

boundary scan related issues and technical writing. He can be reached at tusr@cypress.com tusr@cypress.com.

Click here

Power Developer

iDesign

Product Selection Platform from

ircuit protection is used in virtually every electrical or electronic device, protecting not only the device, but people, businesses, and

reputations. These devices guard sensitive electronics against damage from overcurrent, overvoltage, ESD, surges, and other destructive events, serving as an intentional weak link resulting in controlled rather than catastrophic failure.

PRODUCT WATCH

Power Developer

Circuit protection should be specified as soon as the chipset or other fundamental components have been determined, allowing for proper protection devices to be selected and integrated in the design prior to starting PCB layout. Delaying this critical consideration can result in redoing the layout and less optimal device selection and location leading to a less reliable and potentially unsafe design. Beyond standard cartridge fuses protection devices include PTCs, GDTs, MOVs, ESD suppressors, TVS diodes and arrays, Thyristors, SIDACtors, and LED protectors, each with unique properties, applications, or benefits. These devices should not be thought of as simple commodities to be selected without engineering expertise. Littelfuse provides resources to help designers determine the appropriate protection devices for their specific applications. The Electrostatic Discharge Suppression Design Guide provides an overview of ESD suppression technologies and requirements, types of damage that can occur, as well as design considerations. The guide helps design engineers determine the appropriate suppression technologies for the application with guidance for different data rates and

protocols and provides example protection topologies for various types of ports. The Fuseology Application Guide presents eleven critical factors, going beyond normal operating current and voltage to include ambient temperature, overload current conditions, maximum fault current, pulse conditions, physical constraints, required agency approvals, fuse and fuseholder features, and application testing and verification. By considering these factors, designers will be able to quickly and easily determine the correct fuse. iDesign is the Littelfuse online design and product selection platform. The Fuse Design and Selection Tool incorporates the calculations and requirements set forth in the Fuseology Application Guide, providing users with an intuitive interface for selecting the optimal fuse. The ESD Selection Tool helps designers select from Littelfuseâ&#x20AC;&#x2122;s ESD suppression products and run simulations to compare system ESD levels, identifying the best device for their application. With iDesign, the user provides input at each step with the result being a list of suggested devices based on the input for that design, allowing designers toquickly select a device suited to their application.

PRODUCT WATCH

Select io Fuse C n Guide h and Co aracteristics, nsider ation Fa Terms ctors

ElectrostaticDischarge DischargeSuppression Suppression Electrostatic Design Guide Guide Design Fuseology FuseologySelection Selection Guide Guide Fuse Characteristics, Terms and Consideration Factors

For more information on these and other circuit protection resources, visit www.Speed2Design.com. http://www.speed2design.com To read an article on the iDesign ESD suppression tool, click on this image:

CLIC 37

Power Developer

ZSPM15xx Power Management IC From

PRODUCT WATCH

ZMDIâ&#x20AC;&#x2122;s ZSPM15xx family of digital PWM controllers is designed for high-current, non-isolated DC/DC, step-down point of load converters. The ZSPM15xx comes in a 4mm x 4mm QFN package, offering the highest energy density and smallest footprint. The simplification it presents to designers accelerates time to market while also providing a highly stable supply with a fast transient response in point of load applications.

Power Developer Specs The ZSPM15xx family unique in the market today is that it’s one of the easiest digital power solutions to design-in. The device is preprogrammed with the most common output voltages, eliminating the additional time to implement hardware or software programming. In addition, ZMDI provides recommended BOM and PCB layout resulting in turnkey digital power solution with the highest efficiency and smallest footprint at an optimized cost. Although the ZSPM15xx family is preprogrammed, it still offers users flexibility to customize it to their application. With two external resistor strap pins, users are able to select output compensation, current limit, and output voltage ramp slew rate. To further boost efficiency and reduce time to market, the ZSPM15xx family has been optimized for use with ZMDI’s ZSPM9000 family of DrMOS devices. • Pre-programmed for common voltages • Up to 40A output • State-Law Control— Parallel compensation loops improve steady state and transient response • Optimized for use with ZMDI ZSPM90xx DrMOS devices

PRODUCT WATCH

Hardware Demo Board

Watch Video For more on the ZSPM family of controllers, visit ZMDI.com. To watch a video overview of the ZSPM15xx family, click the image below:

click 41

Power Developer

Power

Triple Lock Connector

From TE Connectivity

PRODUCT WATCH

The Power Triple Lock Connector by TE was developed in direct response to customer feedback. Power Triple Lock is built to provide the highest level of assurance that wire-to-board and wire-to-wire connectors are properly mated during assembly and throughout the product life. Having both wire-to-wire and wire-toboard connectors in the Power Triple Lock family is one reason they are so well suited to applications like smart appliances and other systems. This allows for uniform connectors to be used throughout the system, eliminating the extra tools and costs of using one connector system for wire-to-wire and another for wire-to-board connections.

Power Developer Hardware

CPA

TPA

• Smooth and easy to mate, while providing a more reliable connection • Clearly audible latch with snag-less design • Connector position assurance (CPA) prevents the connectors from disengaging • Terminal position assurance (TPA) prevents terminals from dislodging

PRODUCT WATCH

Features In addition to the features that make the Power Triple Lock a highly reliable connector system, there are multiple color and keying options to further facilitate accurate and quick assembly. Connectors are available with up to three rows and a total of 15 positions. Standard material is rated from -55 to 105ยบC, with high-temperature material rated to 150ยบC, and glow wire material available for appliances requiring compliance with IEC 60335-1. Power Triple Lock rated to 600V and 20A per terminal and is targeted at demanding applications such as home appliances, industrial machinery, HVAC, automotive, and other applications requiring the highest reliability in their connections.

Watch Video For more information, visit TE.com/PowerTripleLock. http://te.com/powertriplelock To watch a video overview, click the image below:

LINK

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Customized

POWER Tri-Mag's Power Products Address the Industry's Toughest Challenges The predominant trend across the tech industry is the move towards ever-shrinking form factors. With wearable devices becoming more popular and the IoT deployment underway, the need for small, seamlessly integrated devices has become a requirement. This poses a difficult set of challenges to all aspects of the industry, especially for power supplies; many of these small IoT devices will need to be continuously powered in order to be readily available for interconnectivity. For Tri-Mag, a leading power components manufacturer, these new, rigid power standards have already been met. The companyâ&#x20AC;&#x2122;s innovative power technologies have been developed to meet this specific set of challenges, from their patented topologies, to their proprietary components in their assemblies to ensure high reliability. EEWeb spoke with Jia-Ming Li, founder of Tri-Mag, about the companyâ&#x20AC;&#x2122;s unique product warranty, their target markets, and some of the impressive performance stats for their power supplies.

INDUSTRY INTERVIEW

Interview with Jia-Ming Li Founder of Tri-Mag

Power Developer

Could you give us a little background about yourself and your role at Tri-Mag? I started Tri-Mag Corporation in 1980. Before that, I worked for Sprague Electric Company, which was the largest component manufacturer in the world at the time. They were located in North Adams, Massachusetts. They have an operation in California and I was transferred to Visalia where I moved up to General Manager from a design engineer. In 1980, Sprague decided to move their operations to San Diego and I didnâ&#x20AC;&#x2122;t want to move, so I stayed in Visalia and started Tri-Mag.

How did you come up with the name Tri-Mag? I started the company with two other people from Sprague, and we wanted to specialize in magnetic products, so it felt appropriate to name it Tri-Mag.

What kind of industry trends have you noticed that you are trying to address with your product offering? The overall industry trend is moving products towards smaller form factors

Tri-Mag has a patent on our topology because it reduces spikes and noise, which, in turn, decreases output filter components.

with higher efficiency. The less power consumption the device uses and the less heat it generates, the more desirable it is nowadays. There is also a trend towards longer lifetime and warranty periods.

What are some of the challenges in providing solutions to meet these needs? In order to meet these needs, you have to start with the design concept and topology. The topology is very important in this process; Tri-Mag has a patent on our topology because it reduces spikes and noise, which, in turn, decreases output filter components. It can reduce the component count, which reduces the size and power supply. The designs that produce fewer spikes exhibit less stress is placed on the MOSFET operation, which allows the use of low-voltage MOSFETs, meaning a higher reliability for the product. Secondly, component selection is very important. You always have to use very good componentsâ&#x20AC;&#x201D;and some of them are quite small. We have selected the latest components that can be used for power supplies. This is directly related to the third important challenge, which is the PCB layout. The layout is crucial to solving the noise and EMI problems. The fourth challenge is assembly technology. The assembly is important to achieve the goal of high reliability.

INDUSTRY INTERVIEW

For example, through-hole component leads are bent/crimped on the solderside of the board to ensure the highest quality (IPC-A-610 Class 3) soldered connection during the wavesoldering process. We also adhere very heavy components to the PCB to make sure it or nearby components are not damaged due to vibration. The heavy components are typically the transformers and electrolytic capacitor, so they must be bonded to the PCB and/or other components. After the assembly process, we make sure that we go through computer testing to test every component and function. The key components like transformers and magnetic inductors are made in-house so we can guarantee the required performance and quality specifications are met. We are also able to control the schedule for manufacturing and we applied a small, lean manufacturing style production line concept for more flexibility to adjust the production schedule, making it much easier to measure and control the quality and reliability. We have quality control inspection as well that takes samples from the production line and they perform every test to compare to the original design detail to make sure the product meets the specifications of the original design. These processes are put in place to

The key components like transformers and magnetic inductors are made in-house so we can guarantee the required performance and quality specifications are met. ensure that we achieve the required quality and performance standards that allow us to offer a ten-year warranty on many of our products. Proven design and manufacturing practices coupled with discerning component selection allow us to offer such a superior warranty over a standard two-year warranty.

You mentioned you had a patent on voltage spikes and noiseâ&#x20AC;&#x201D;could you speak to how you were able to achieve this? The goal was to reduce the spike because sometimes with the power supplies, the spikes can be quite high. They spike because of the transient response, which usually kills the MOSFET. In order to reduce these spikes, we implement capacitors and resistors in the circuit. However, this increases the amount of components on the board. If we can reduce the spike, then we can reduce the component count. Often, the spikes can be 800V, which is quite high. Our designs reduce these spikes to around 450V, which is a big difference.

Power Developer

Tri-Mag is the first power supply company to offer a ten-year warranty in the market.

In the world of power supplies, obviously LED lighting is quite popular now. Can you speak to some of the differences in designing a voltage source, which is what people typically look for, and a current source, which is what you typically look for in the LED market? Most people use the LED driver as the constant current type power supply. The power supplies have two types: constant current and constant voltage. The smaller LEDs generally require constant current sources, while the larger LED arrays implement a constant voltage source. For outdoor scoreboard displays, the power supplies must meet demanding temperature and humidity requirements. Tri-Mag provides power supplies for some of the scoreboard displays in the Chicago area. In the winter in Chicago, it can be negative 20 degrees and in the summer it can be upwards of 100 degrees. This is a big range in temperatures and the power supplies have to withstand this type of fluctuation. They must also be able to start in -20 degrees, or else it cannot power these displays. The humidity can also be an issue in the summertime in these urban areas, and the supplies must be able to withstand this type of humidity.

What is Tri-Magâ&#x20AC;&#x2122;s target market? Tri-Mag does not target the lowcost market area. Our price is very competitive to the market, but we offer a much higher quality product, with a longer warranty period. Tri-Mag is the first power supply company to offer a ten-year warranty in the market. Tri-Mag also offers power supplies for in-home medical equipment. The industry recently posed new standards for medical devices, requiring each device to use Class 2 power supplies. Tri-Magâ&#x20AC;&#x2122;s medical-grade power supplies meet all IEC60601-1 3rd edition requirements, including 2XMOPP (Means of Patient Protection) and 1XMOOP (Means of Operator Protection). Customers are assured of safety compliance that meets or exceeds all international standards. These medical-grade supplies are suited for patient monitoring devices, surgical, imaging, laboratory equipment, and home healthcare devices. There are new requirements from the US Department of Energy that states you have to meet Level 6 power supplies, and we are the first company to come out with these types of power supplies. The requirement to introduce the Level 6 status is February of 2016, but we have already met that.

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The Leading Edge of SOLAR Revolutionary Solar Cell Technology Delivers High Efficiency at a Low Cost

EEWEB FEATURE

Renewable energy technology has been a part of the American energy infrastructure for decades now—taking the form of wind turbines, home-installed solar panels, and even water wheels. As awareness of our negative impact on the Earth’s climate and environment increases, so does the cost of the fuel. Interestingly enough, our dependence on finite fuel resources has not faltered, despite advancements in renewable energy technology like solar. So why hasn’t solar replaced nuclear power plants in the US? Well, for one, solar technology has not yet reached grid parity—the point in which it becomes cheaper than purchasing power from electric grids—which is a crucial achievement in order for the mass adoption of solar technology. However, this is all beginning to change. One company in particular—Natcore Technology—has developed a new method of assembling solar cells that not only boosts efficiency, but lowers the cost of implementation down to a point where we might be seeing a lot more solar panels in the neighborhood. EEWeb spoke with Natcore’s President and CEO, Chuck Provini, about their revolutionary heterojunction cell technology, how it will enable mass adoption of solar panels, and the company’s exciting new |partnership with Eurotron, a Dutch solar equipment manufacturing company.

Power Developer

ast year, EEWeb interviewed Dennis Flood of Natcore about their proprietary liquid-phase deposition process that was believed to be the next big thing in terms of mass solar adoption. The announcement of this technology certainly made waves, establishing Natcore as a force in the solar technology industry. However, Provini was excited about the new advancements Natcore has achieved since then: “When Natcore was first starting out, we felt that our most important technology was our liquid phase deposition [LPD], which we thought was our home run.” The technology utilized a room-temperature liquid bath that suspended the particles and spread it out to create a film, which was branded as the company’s “special sauce.” But the secret to success is now taking a different form for Natcore, “We are so far beyond LPD now that we don’t even remember what that was,” Provini jokingly stated.

“We are so far beyond [liquid-phase deposition] now that we don’t even remember what that was.”

Natcore’s new technology is their backcontact heterojunction cells, which they believe is the fastest way to achieve 25%

efficiency—the number that every solar company is trying to achieve. In essence, Natcore’s technology is allowing solar cells to be made in a low-temperature, ambient pressure process. This eliminates the high temperatures that typically come with antireflective (AR) coatings, which allow the cell to become much more efficient. A typical manufacturing process takes a polysilicon wafer and puts it through a high-temperature step, which ultimately damages it and restricts how efficient the cell can be. “Using our laser process,” Provini explained, “when we do use high temperatures, it is only at a very specific location on the wafer, so we are using specific temperatures for nano-sized dots where they need to be.” The low-temperature, laser-processed, all-back-contact HIT-cell structure is already in advanced stages of development, and the technology could soon be offered to solar panel manufacturers to achieve the sought-after 25% efficiency rating. However, Provini is adamant about explaining Natcore’s role as a solar technology developer, not a manufacturer: “We have been on Fox News and in the New York Times, and people would start calling me up and asking me to send over some solar cells and panels, and I had to keep reiterating that we didn’t have any.” This allows Natcore to dodge the headache of creating a manufacturing plant, which in turn allows them to focus primarily on developing revolutionary technologies. “We don’t want to manufacture, we want to be the manufacturer’s friend,” Provini explained.

EEWEB FEATURE

The result is a “best-of-breed” service, which allows Natcore to take advantage of the relationships it has formed with actual manufacturers. With this service, Natcore acts as a consultant to companies that want to build a manufacturing facility. Natcore will then act as a consultant to pick the best possible equipment that fits the need of the customer. According to Provini, “If a company engages Natcore to do that, we will then give this new entity exclusive rights to our technology as it comes down the line.” This best-ofbreed relationship allows both Natcore and the manufacturers to always be at the leading edge of the industry. One of Natcore’s more recent partnerships has been with the Dutch solar module manufacturer, Eurotron. In March of this year, Natcore and Eurotron signed a joint development deal, which will synthesize both company’s significant advancements in back-contact solar cells. Eurotron was of interest to Natcore because their solar cells utilize a thin layer of interconnection foil on the back of the solar cell. Jan Bakker, CTO of Eurotron, told EEWeb: “This technique increases the output of the solar module because there is less shadow on the top layer of the solar cell.” Bakker went on to state that the interconnection behind the cells allows for the use of more copper to connect the cells together, which also lowers resistance while giving the module more power output. Another major benefit of Eurotron’s

“We don’t want to manufacture, we want to be the manufacturer’s friend.”

solar cell modules is their size. “There is less silver on our solar cell,” Bakker said, “which means there is less dead area on the module.” This makes Eurotron’s modules significantly smaller than standard modules. “We can place solar cells closer to each other and because of the lower resistance the overall temperature of the module is also lower.”

Laser components used in applying contacts to the back of solar cells.

These features will pair nicely with Natcore’s heterojunction, backcontact solar technology. Eurotron’s Netherlands facility can assist Natcore by making full-sized solar modules to demonstrate just how well this type of solar module operates. Provini explained that, “Eurotron has a technology that, in essence, will make our technology easier to integrate into the solar panel industry.” Provini believes that Eurotron’s technology will be the

Power Developer fastest path to those efficiency numbers that will make mass adoption of solar a reality. However, once those efficiency numbers are achieved, the innovation will not stop there. Provini detailed that Natcore spends a majority of their budget on research and development as well as marketing, made possible by the fact that they do not manufacture products. Natcore’s business model makes innovation the priority, meaning it will easily adapt to the rapidly changing and expanding solar industry. Provini remained optimistic about the future: “Hopefully, if we were to have another conversation in six months, it would be about an entirely new technology that will be at the leading edge of the industry.”

Eurotron’s technology will be the fastest path to those efficiency numbers that will make mass adoption of solar a reality. Platform, ready for now and the future Glass Encapsulant Backcontact cells

Encapsulant with holes

Conductive material Contactfoil Backsheet

Euromax 250MWp line Eurotron’s Euromax 250MWp production line.

MYLINK

Power Developer

Semitrexâ&#x20AC;&#x2122;s Tronium Chips Target

POWER DEMANDS of the Future

EEWEB FEATURE

Energy efficiency is becoming a prerequisite for any power device coming into the market. The International Energy Agency (IEA) calculates that the demand for energy in network-enabled devices is growing at a rate of 6 percent each year, with an estimated rate of 1,000 terawatt-hours consumed by the year 2022. With this growth in energy demands and consumption comes significant energy waste at a global scale. This picks up on what is known as â&#x20AC;&#x153;vampire power,â&#x20AC;? referring to lost power when electronic devices are switched off or put into standby mode.

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Semitrex company overview Semitrex was founded by Michael H. Freeman in 2012 as a fabless power semiconductor research and development company based on Freeman’s capacitor innovations.

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TRONIUM CORE ASIC

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Semitrex Headquarters ampire load is responsible for 105 Crescent Bay Dr. $80 billion of losses Laguna Beach, around CA 92651the world. The problem is so serious Midwest office that the U.S. government is enacting Research Center locationS Level VI energy Semitrex efficiency standards— 1701 S Carson Ave. set to take effect in 2016—that place Tulsa, OK 74119 stringent limitations to output current in IP some & ADMIN power supplies. For power supply office companies, a year isFargo a short amount Wells Tower, Suite 1007 3800 Howard Hughes of time to overhaul their productsParkway to Las Vegas, NV 89169-5980 meet the Level VI requirement—but WEBSITE for Semitrex, a fabless semiconductor www.semitrex.com company addressing the issue of energy consumption, that requirement has already been met and exceeded by two hundred times. With its Tronium suite of innovative power management solutions, Semitrex eliminates the vampire load while targeting the higher efficiency power demands of the future.

The Tronium Power Supply System on a Chip (PSSoC) is a compact and robust power management and supply system. Semitrex’s Tronium chips offer three major innovative features that will lead to less expensive, highly-efficient end products. The first feature is the unique pre-regulation voltage conversion

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technology called Muxcapacitorâ&#x201E;˘. This technology is based on capacitive voltage reductions as opposed to inductive reductions. As a result, there are no magnetic components, making it suitable for operating at high voltages while maintaining an impressively high efficiency level compared to traditional flyback converters. Muxcapacitor utilizes cascading capacitors managed by algorithms, which reduce the breakdown ratio of voltages to achieve the desired high efficiencies. Changing the algorithms also permits a Dial-a-Voltageâ&#x201E;˘ feature in the Tronium PSSoC, which allows the chip to be programmed to any desired voltage outputs from 1.8 volts to 48 volts. This programmability reduces the need for additional power supplies to cater to different voltage requirements; the single chip can span from 1.8- to 48-volts and is compatible with voltages all over the world. Dial-a-Voltage allows for Tronium to be implemented across virtually any industry that needs a power supply, from powering microcontrollers to outdoor lighting applications.

Muxcapacitor utilizes cascading capacitors managed by algorithms, which reduce the breakdown ratio of voltages to achieve the desired high efficiencies.

Dial-a-Voltage allows for Tronium to be implemented across virtually any industry that needs a power supply, from powering microcontrollers to outdoor lighting applications.

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The streamlined functionality of this PSR technology eliminates the need for opto-couplers, which helps reduce the part count from 50 to less than 25.

Semitrex also offers its own version of Primary Side Regulation (PSR) technology. Unlike competitors’ PSR technology, Tronium does not require a third winding to start sensing—rather, it senses directly off the primary side of the inductor off the transformer. The streamlined functionality of this PSR technology eliminates the need for opto-couplers, which helps reduce the part count from 50 (in a typical flyback configuration) to less than 25. Lower part count means not only a lower overall cost in end applications but an extreme reduction in size. For example, a typical 60-inch television has over 500 parts in it—300 electronic parts and 200 mechanical. The size reduction benefits of the Tronium solution could reduce this part count up to 90 percent. The industry that will benefit most from this power conversion technology is the burgeoning Internet of Things. Removing part counts and reducing size and operating efficiency of devices will ultimately lead to connected devices that will be small enough to blend in with the user’s surroundings. Semitrex has

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recognized the impending explosion of IoT devices with the creation of the pwIoT (pronounced “p-watt”) Tronium power module, which does not need a transformer. The pwIoT functionality transforms Tronium into a plug-and-play chip solution for connected devices to ensure high efficiency extending all the way down to virtually zero standby power consumption, with only ½ milliwatt of standby power needed to keep the system “alive” and ready for the next power-up event. This means that devices will not be wasting power when they are idling or not in use, which will reduce the costly vampire load. The pwIoT solution can also be monitored and controlled wirelessly for ease of use and higher reliability, which is just as intuitive and flexible as the IoT devices they will power. With power demands steadily growing each year, Semitrex’s Tronium PSSoC anticipates the industry trends and addresses them at every level. Its high standard of operating power efficiency and cost reduction has already far surpassed the IEA’s new efficiency standards, meaning it is one step ahead of the energy efficiency trends.

The pwIoT functionality transforms Tronium into a plug-and-play chip solution for connected devices to ensure high efficiency extending all the way down to virtually zero standby power consumption.

Semitrex’s combined technologies dramatically reduces existing flyback topology part count.

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