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LNK605DG-TL
LED Driver AC/DC, CV/CC Switcher, Flyback, 90V to 265V Input, 65W, 80kHz, 1 Output, SOIC-8
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- Manufacturer: POWER INTEGRATIONS
- Product type: AC / DC LED Driver ICs
- Device Topology:Flyback; Input Voltage Min:90V; Input Voltage Max:265V; Output Voltage Max:12.1V; Output Current Max:300mA; Switching Frequency:80kHz; No. of Outputs:1Outputs; IC
- MSL: MSL 1 - Unlimited
- SVHC: No SVHC (21-Jan-2025)
- Topology: Flyback
- IC Mounting: Surface Mount
- No. of Pins: 8Pins
- Product Range: LinkSwitch-II Series
- Qualification: -
- No. of Outputs: 1Outputs
- Device Topology: Flyback
- LED Driver Type: Isolated
- Driver Case Style: SOIC
- IC Case / Package: SOIC
- Input Voltage Max: 265V
- Input Voltage Min: 90V
- Output Current Max: 300mA
- Output Voltage Max: 12.1V
- Switching Frequency: 80kHz
- Switching Frequency Typ: 80kHz
- Operating Temperature Max: 150°C
- Operating Temperature Min: -40°C
- Automotive Qualification Standard: -
| Delivery and price | |
|---|---|
| Units per pack | 2500 |
| Price | 0.581 € |
| Current stock | 200+ |
| Lead time | 30 days |
Datasheet
||**Design Example Report**| |---|---| |**Title**|**_High Efficiency (≥75%), 3.6 W Isolated LED_**<br>**_Driver Using LinkSwitchTM-II LNK605DG_**| |**Specification**|90 VAC – 265 VAC Input; 12 V, 0.3 A Output| |**Application**|LED Driver for GU10 Lamp| |**Author**|Applications Engineering Department| |**Document**<br>**Number**|DER-261| |**Date**|September 24, 2010| |**Revision**|1.5| ## **Summary and Features** - Low cost, low component count and small printed circuit board footprint solution - Frequency jitter for smaller, lower cost EMI filter components - Primary side control eliminates secondary side control and optocoupler and provides +/-5% CV and +/-10% CC accuracy - Integrated protection and reliability features - Output open circuit / output short-circuit protected with auto-recovery - Over-temperature protection – tight tolerance (+/-5%) with hysteretic recovery for safe PCB temperature under all conditions - Extended package pin creepage distance for reliable operation in humid environments - >3.2mm at package - Designed to meet - EN55015B conducted EMI with >10 dBµV margin - IEC61000-4-5 Class 3 AC line surge - IEC61000-4-2 ESD at 4 kV contact / 8 kV air. - Ultra-low AC leakage current: <5 μA at 265 VAC input (no Y capacitor required) - EcoSmart[TM] - No-load consumption: <50 mW at 265 VAC - Efficiency: ≥75% at both 115 VAC and 230 VAC **Power Integrations** 5245 Hellyer Avenue, San Jose, CA 95138 USA. Tel: +1 408 414 9200 Fax: +1 408 414 9201 _www.powerint.com_ DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ## PATENT INFORMATION The products and applications illustrated herein (including transformer construction and circuits external to the products) may be covered by one or more U.S. and foreign patents, or potentially by pending U.S. and foreign patent applications assigned to Power Integrations. A complete list of Power Integrations' patents may be found at www.powerint.com. Power Integrations grants its customers a license under certain patent rights as set forth at <http://www.powerint.com/ip.htm>. **==> picture [59 x 34] intentionally omitted <==** **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 2 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## **Table of Contents** |1|Introduction.................................................................................................................5|Introduction.................................................................................................................5| |---|---|---| |2|Power Supply Specification ........................................................................................7|| |3|Schematic...................................................................................................................8|| |4|Circuit Description.......................................................................................................9|| ||4.1|Input Filtering.......................................................................................................9| ||4.2|LinkSwitch-II Primary...........................................................................................9| ||4.3|Output Rectification .............................................................................................9| |5|PCB Layout...............................................................................................................10|| |6|Bill of Materials .........................................................................................................11|| |7|Transformer Specification.........................................................................................12|| ||7.1|Electrical Diagram..............................................................................................12| ||7.2|Electrical Specifications.....................................................................................12| ||7.3|Materials............................................................................................................12| ||7.4|Transformer Build Diagram................................................................................13| ||7.5|Transformer Construction..................................................................................13| ||7.6|Step and Procedure for Wrapping Insulation Tape on Transformer ..................14| ||7.7|Preparation of Assembly Details........................................................................15| ||7.8|Assembly of Transformer to PCB ......................................................................16| |8|Transformer Design Spreadsheet.............................................................................17|| |9|Performance Data.....................................................................................................20|| ||9.1|Efficiency vs. Line and Output Voltage ..............................................................20| ||9.2|No-Load Power Consumption............................................................................21| ||9.3|Output Characteristic.........................................................................................22| |10||Thermal Performance............................................................................................24| ||10.1|Measurement with Infrared Camera (Open Frame)...........................................24| ||10.1.1<br>VIN= 115 VAC ............................................................................................24|| ||10.1.2<br>VIN= 230 VAC ............................................................................................24|| ||10.2|Measurement with Thermocouples (Inside Enclosure)......................................25| |11||Waveforms............................................................................................................26| ||11.1|Drain Voltage and Current.................................................................................26| ||11.2|Drain Voltage and Current Start-up Profile ........................................................26| |12||Line Surge.............................................................................................................27| |13||Hipot Test..............................................................................................................28| |14||ESD Test...............................................................................................................28| |15||Conducted EMI .....................................................................................................29| |16||Revision History ....................................................................................................33| **==> picture [59 x 34] intentionally omitted <==** **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 3 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 **Important Note:** Although this board is designed to satisfy safety isolation requirements, the engineering prototype has not been agency approved. Therefore, all testing should be performed using an isolation transformer to provide the AC input to the prototype board. **==> picture [59 x 34] intentionally omitted <==** **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 4 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## **1 Introduction** The document describes a high efficiency LED driver designed to drive 12 V at 0.3 A from an input voltage range of 90 VAC to 265 VAC. The LED driver uses the LNK605DG from the LinkSwitch-II family by Power Integrations. LinkSwitch-II ICs allow the implementation of cost effective and low component count LED drivers meeting the compact design and high efficiency requirements necessary for high temperature operating environments. The topology used is an isolated flyback operating in discontinuous conduction mode. Output current regulation is sensed entirely from the primary side eliminating the need for secondary side feedback components. No external current sensing is required on the primary side either as this is performed inside the IC further reducing components and losses. The LNK605DG also provides a sophisticated range of protection features including autorestart for open control loop and output short-circuit conditions. Accurate hysteretic thermal shutdown ensures safe average PCB temperatures under all conditions. In LED luminaires the driver determines many of the performance attributes experienced by the end user including startup time and unit to unit consistency. For this design, the LNK605DG device ensures unit to unit consistency with an output CC tolerance of <10%, fast startup time of <5 ms for instant on performance and long lifetime and high reliability due to the low component count. This document contains the LED driver specification, schematic, PCB diagram, bill of materials, transformer documentation and typical performance characteristics. **==> picture [59 x 34] intentionally omitted <==** **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 Page 5 of 34 www.powerint.com DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 **Figure 1** – Populated Circuit Board Photograph. **Figure 2** – Assembled Driver Inside GU10 Base. **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 6 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## **2 Power Supply Specification** The table below represents the minimum acceptable performance of the design. Actual performance is listed in the results section. |**Description**|**Symbol**|**Min**|**Typ**|**Max**|**Units**|**Comment**| |---|---|---|---|---|---|---| |**Input**<br>Voltage<br>Frequency|**VIN**<br>**fLINE**|90<br>47|115/230<br>50/60|265<br>64|VAC<br>Hz|2 Wire – no P.E.| |**Output**<br>Output Voltage<br>Output Current<br>**Total Output Power**<br>Continuous Output Power|**VOUT**<br>**IOUT**<br>**POUT**|10.5|11<br>0.3<br>3.6|12.1|V<br>A<br>W|VOUT= 12, VIN= 230 / 115 VAC,<br>25°C| |**Efficiency**<br>Full Load||75|||%|Measured at POUT25 oC and<br>input 115 / 230 VAC| |**Environmental**<br>Conducted EMI<br>Safety<br>ESD||Meets CISPR 15B / EN55015B<br>Designed to meet IEC950 / UL1950 Class II<br>4<br>8<br>kV<br>kV||||Contact Discharge<br>Air Discharge| |Ring Wave (100 kHz)<br>Differential Mode (L1-L2)|||2||kV|EN 61000-4-5 , 200 A| |Ambient Temperature|**TAMB**||70||oC|Free convection, sea level| Notes: - Ambient temperature is specified with a small heatsink added on the PCB next to LinkSwitch-II device. **==> picture [59 x 34] intentionally omitted <==** **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 Page 7 of 34 www.powerint.com DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ~~**e** ner~~ eee **e** ## **3 Schematic** **Figure 3** – Schematic. **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 8 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## **4 Circuit Description** The LinkSwitch-II device is an integrated controller plus 700 V power MOSFET intended for use in LED driver or charger applications. The LinkSwitch-II is configured for use in a single-stage discontinuous conduction mode flyback topology and provides a primary side regulated constant voltage and current output. ## _**4.1 Input Filtering**_ AC input power is rectified by bridge rectifier BR1. The rectified DC is filtered by the bulk storage capacitors C1 and C2. Inductors L1, C1 and C2 form a pi (π) filter, which attenuates conducted differential-mode EMI noise. This configuration along with Power Integrations transformer E-shield technology allow this design to meet EMI standard EN55015 Class B with good margin without requiring a Y capacitor. The transformer construction also gives very good EMI repeatability. Fusible resistor RF1 provides protection against catastrophic failure. This should be a wire wound type to withstand the instantaneous dissipation when first connected to AC while the input capacitors charge. ## _**4.2 LinkSwitch-II Primary**_ The LNK605DG device (U1) incorporates the power switching device, oscillator, CC/CV control engine, startup, and protection functions. The integrated 700 V power MOSFET allows for sufficient voltage margin in universal input AC applications. The device is powered from the BYPASS pin via the decoupling capacitor C4 during startup. The rectified and filtered input voltage is applied to one end of the primary winding of T1. The other side of the transformer’s primary winding is driven by the integrated 700 V power MOSFET in U1. The leakage inductance drain voltage spike is limited by an RCDR clamp consisting of D1, R3, R4, and C3. Diode D2, C5 and R10 create the primary bias supply. This voltage created from the transformer bias winding supplies bias current into the BYPASS pin through D2 and R10. The LNK605DG can be configured with or without an optional bias supply. When configured to be supplied from a bias supply (as in this design), the no-load power consumption reduces to <50 mW. ## _**4.3 Output Rectification**_ The secondary of the transformer is rectified by D3; a Schottky barrier type was selected for higher efficiency, and filtered by C7. For this application a ceramic capacitor was selected for C7 to provide longer life time compared to an electrolytic type due to the high operating ambient temperature. Resistor R1 and C6 dampen high frequency ringing and reduce the diode voltage stress. **==> picture [59 x 34] intentionally omitted <==** **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 9 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ## **5 PCB Layout** **Figure 4** – Printed Circuit Layout (Designed to Fit Inside GU10 Lamp Form Factor). 24.31 mm (L) x 16.50 mm x 13.50 mm. **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 ~E= ~~©~~ www.powerint.com . Page 10 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## **6 Bill of Materials** |**Item**|**Qty. **|**Ref Des**|**Description**|**Mfg Part Number**|**Manufacturer**| |---|---|---|---|---|---| |1|1|BR1|600 V,0.5 A,Bridge Rectifier,SMD,MBS-1,4-SOIC|MB6S|Micro Commercial| |2|1|C1 C2|3.3F,400 V,Electrolytic, (6.3 x 12)|TM1332PE12MCP|YIH HONG MAO<br>Electronics Co.| |3|1|C3|470pF,250 V,Ceramic,X7R,0805|ECJ-2VB2A471K|Panasonic| |4|2|C4 C5|1F,25 V,Ceramic,X7R,0805|ECJ-2FB1E105K|Panasonic| |5|1|C6|470pF 50 V,Ceramic,X7R,0603|ECJ-1VC1H471J|Panasonic| |6|1|C7|10F,25 V,Ceramic,X7R,1206|ECJ-3YB1E106M|Panasonic| |7|1|D1|1000 V, 1 A, Rectifier, Glass Passivated, DO-213AA<br>(MELF)|DL4007-13-F|Diodes Inc| |8|1|D2|75 V,0.15 A,Fast Switching,4 ns,MELF|LL4148-13|Diode Inc.| |9|1|D3|100 V,1 A,Schottky,DO-214AC(SMA)|SS110|Micro commercial.| |10|1|L1|1000H,0.08 A,Ferrite Core,Shielded|1641-105K|API Delevan| |11|1|R1|8.2,5%,1/10 W,Thick Film,0603|ERJ-3GEYJ8R2V|Panasonic| |12|1|R3|390 k,5%,1/4 W,Thick Film,1206|ERJ-8GEYJ394V|Panasonic| |13|1|R4|330,5%,1/8 W,Thick Film,0805|ERJ-6GEYJ331V|Panasonic| |14|1|R6|3.3 k,5%,1/10 W,Thick Film,0603|ERJ-3GEYJ332V|Panasonic| |15|1|R8|46.4 k,1%,1/16 W,Thick Film,0603|ERJ-3EKF4642V|Panasonic| |16|1|R9|8.06 k,1%,1/16 W,Thick Film,0603|ERJ-3EKF8061V|Panasonic| |17|1|R10|6.2 k,5%,1/10 W,Thick Film,0603|ERJ-3GEYJ622V|Panasonic| |18|1|RF1|10,1 W,Fusible/Flame Proof Wire Wound|CRF251-4 10R|Vitrohm| |19|1|T1|Bobbin,EE13,Vertical,8pins|BE13-1110CPSFR|TDK| |20|1|U1|LinkSwitch-II,LNK605DG,CV/CC,SO-8C|LNK605DG|Power Integrations| **==> picture [59 x 34] intentionally omitted <==** **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 Page 11 of 34 www.powerint.com DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ## **7 Transformer Specification** ## _**7.1 Electrical Diagram**_ **Figure 5** – Transformer Electrical Diagram. ## _**7.2 Electrical Specifications**_ |**Electrical Strength**|1 second,60 Hz,frompins 1,2,7,8 to A,B|3000 VAC| |---|---|---| |**Primary Inductance**|Pins 1 - 2, all other windings open, measured at 100 kHz,<br>0.4 VRMS|1.10 mH ±10%| |**Resonant Frequency**|Pins 1 - 2,all other windings open|750 kHz(Min.)| |**Primary Leakage**<br>**Inductance**|Pins 1 - 2 with A - B shorted, measured at 100kHz,<br>0.4 VRMS|35H ±10%| ## _**7.3 Materials**_ |**Item**|**Description**| |---|---| |**[1]**|Core: PC40 from TDK or equivalent,ALG = 1130.00nH/n2| |**[2]**|Bobbin: 8pin vertical,BE13-1110CPSFR from TDK,or equivalent| |**[3]**|Magnet Wire: 0.21mm Diameter.| |**[4]**|Magnet Wire: 0.15mm Diameter.| |**[5]**|Magnet Wire: 0.4mm Diameter.| |**[6]**|Magnet Wire: 0.2mm Diameter T.I.W.| |**[7]**|Tape: 3M 1298 Polyester Film,8 mm wide.| |**[8]**|Tape: 3M 1298 Polyester Film,12 mm wide and 156 mm long.| |**[9]**|Tape: 3M 1298 Polyester Film,14 mm wide and 182 mm long.| |**[10]**|Varnish.| **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 12 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## _**7.4 Transformer Build Diagram**_ ## **Pins Side** **Figure 6** – Transformer Build Diagram. ## _**7.5 Transformer Construction**_ |**Bobbin**<br>**Preparation**|Place the bobbin item [2] on the mandrel such that pin side on the left side. Winding<br>direction is the clockwise direction.| |---|---| |**WD 1**|Start at pin 1, wind 30 turns of 0.21 mm item [3] from left to right in one layer. Cut the end<br>of the wire to leave it NC(no connection).| |**Insulation**|Applyone layer of tape[7]for insulation.| |**WD 2**|Start at pin 2, wind 40 turns of 0.15 mm item [4] from left to right with tight tension, and<br>apply 1 layers layer of tape [7]. Continue winding 40 turns of item [4] from right to left and<br>finished atpin 1.| |**Insulation**|Applyone layer of tape[7]for insulation.| |**WD 3**|Start atpin 7,wind 15 turns of 0.4 mm[5]wire from left to right. Finish atpin 8.| |**Insulation**|Applyone layer of tape[7]for insulation.| |**WD 4**|Continue to wind with floating wire, 16 turns of 0.2 mm T.I.W wire [6] from left to right.<br>Start marked as A and finish marked as B.| |**Insulation**|Applytwo layers of tape[7]for insulation.| |**Final**<br>**Assembly**|Cut A, B wires length to 0.75”. Grind core. Assemble core. Varnish using item [10] and<br>wrapthe transformer usingitem[8], [9]. Refer the 7.6 for transformer insulation wrap.| **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 Page 13 of 34 www.powerint.com DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ## _**7.6 Step and Procedure for Wrapping Insulation Tape on Transformer**_ |Step 1|**Item [8]**<br>> 6mm<br>No pin side to be<br>covered with tape<br>nd<br>|<br>—|*<br>|-—|Transformer to be wrapped<br>with all electrical tests and<br>varnishing completed.<br>The wrapping is started at the<br>no-pin side.<br>Wrap the insulation tape item<br>[8] on to the no pin side area<br>and make sure the tape has<br>extended and covered the<br>core by at least 6mm.| |---|---|---| |Step 2||Fully wrap the tape around the<br>transformer with minimum 3<br>turns with item [8]| |Step 3<br>~~me~~|Start to fold<br>Completed all<br>the folds (4x)<br>=-<br>es<br>a<br>~~me~~|Bend the tape inward and<br>make a complete fold to all the<br>4 sides.<br>~~me~~| |Step 4<br>~~me~~<br>~~2.~~|Start<br>Finish<br>**Item [9]**<br>~~me~~<br>~~2.~~<br>~~ee~~|Wrap the insulation tape item<br>[9] on to the core side of the<br>assembly with minimum of 3<br>turns.<br>Allow the tape to be covered<br>upto the termination.<br>~~me~~<br>~~ee~~| |Step 5<br>~~me~~<br>~~2.~~|> 4 mm<br>Completed<br>Assembly<br>Transformer’s pins<br>Transformer’s pins<br>~~me~~<br>~~2.~~<br>~~ee~~|Complete assembly and leave<br>~4<br>mm<br>of<br>the<br>lead<br>for<br>soldering.<br>~~me~~<br>~~ee~~| **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 EE www.powerint.com Page 14 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## _**7.7 Preparation of Assembly Details**_ **==> picture [407 x 339] intentionally omitted <==** **----- Start of picture text -----**<br> Preparation of copper heatsink and fusible resistor<br>Item-A: Copper heatsink to<br>be protected with HS tube.<br>Item-B: Fusible resistor to be<br>protected with HS tube.<br>Item-A: Protect copper heatsink with heat shrinkable tube<br>Heatsink plate and heat-shrinkable or<br>Sleep the HS tube with the<br>HS tube was prepared. Finished assembly and ready<br>The HS tube could be in any color copper heatsink and applied to be inserted into PCB<br>heat.<br>and must be UL recognized.<br>**----- End of picture text -----**<br> Item-A: Protect copper heatsink with heat shrinkable tube **==> picture [301 x 10] intentionally omitted <==** **----- Start of picture text -----**<br> Item-B: Protect fusible resistor with heat shrinkable tube<br>**----- End of picture text -----**<br> **==> picture [141 x 164] intentionally omitted <==** **----- Start of picture text -----**<br> Heatsink plate and fusible resistor<br>was prepared.<br>The HS tube could be in any color<br>and must be UL recognized.<br>Sleep the HS tube with Fusible resistor<br>and applied heat.<br>Finished assembly and ready to be<br>inserted into PCB.<br>**----- End of picture text -----**<br> **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 15 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ## _**7.8 Assembly of Transformer to PCB**_ **==> picture [433 x 517] intentionally omitted <==** **----- Start of picture text -----**<br> Step-1 Insert HS tube to the protected areas<br>PCB assembly completed wave-<br>soldering<br>Transformer assembly<br>~*~, . * 4 a '¢<br>Prepared HS tube with (Φ6 x<br>20 mm). Fully insert it into the<br>secondary area of PCB.<br>20mm<br>—_.<br>Step-2 Shrink the HS tube<br>4 ‘ rf -<br>:<br>Apply heat to the tube and shrink<br>on the assembly, make a bend at<br>Bend up the end of tube to create access<br>safety distance.<br>Step-3 Assembly completed<br>i<br>=<br>Insert the transformer on to the<br>PCB and manually solder it<br>SS ae termination pins (4x) on the PCB.<br>**----- End of picture text -----**<br> ## **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 16 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## **8 Transformer Design Spreadsheet** |**ACDC_LinkSwitch-**<br>**II_120209; Rev.1.11;**<br>**Copyright Power**<br>**Integrations 2009**|**INPUT **|**INFO**|**OUTPUT **|**UNIT**|**ACDC_LinkSwitch-II_120209_Rev1-**<br>**11; LinkSwitch-II Discontinuous**<br>**Flyback Transformer Design**<br>**Spreadsheet**| |---|---|---|---|---|---| |**ENTER APPLICATION VARIABLES**|||||| |VACMIN|90|||V|Minimum AC Input Voltage| |VACMAX|265|||V|Maximum AC Input Voltage| |fL|50|||Hz|AC Mains Frequency| |VO|12|||V|Output Voltage (at continuous power)| |IO|0.3|||A|Power Supply Output Current<br>(correspondingtopeakpower)| |Power|||3.60|W|Continuous Output Power| |n|0.76||0.76||Efficiency Estimate at output terminals.<br>Under 0.7 if no better data available| |Z|||0.50||Z Factor. Ratio of secondary side<br>losses to the total losses in the power<br>supply. Use 0.5 if no better data<br>available| |tC|||3.00|ms|Bridge Rectifier Conduction Time<br>Estimate| |Add Bias Winding|YES||N/A||!!! Info. Bias winding is not necessary.<br>The feedback winding itself can be<br>used to provide exteral bias to the<br>LinkSwitch| |CIN|6.6|||uF|Input Capacitance| |**ENTER LinkSwitch-II VARIABLES**|||||| |Chosen Device|LNK605||LNK605||Chosen LinkSwitch-II device| |Package|DG||DG||Select package (PG, GG or DG)| |ILIMITMIN|||0.30|A|Minimum Current Limit| |ILIMITTYP|||0.31|A|Typical Current Limit| |ILIMITMAX|||0.35|A|Maximum Current Limit| |FS|80||80.00|kHz|Typical Device Switching Frequency at<br>maximumpower| |VOR|||62.50|V|Reflected Output Voltage (VOR < 135<br>V Recommended)| |VDS|||10.00|V|LinkSwitch-II on-state Drain to Source<br>Voltage| |VD|||0.50|V|Output Winding Diode Forward Voltage<br>Drop| |KP|||1.88||Ensure KDP > 1.3 for discontinuous<br>mode operation| |**FEEDBACK WINDING PARAMETERS**|||||| |NFB|||15.00||Feedback winding turns| |VFLY|||11.72|V|Flyback Voltage - Voltage on<br>Feedback Winding during switch off<br>time| |VFOR|||14.71|V|Forward voltage - Voltage on<br>Feedback Winding during switch on<br>time| |**BIAS WINDING PARAMETERS**|||||| |VB|||N/A|V|Feedback Winding Voltage (VFLY) is<br>greater than 10 V. The feedback<br>winding itself can be used to provide<br>exteral bias to the LinkSwitch.<br>Additional Bias windingis not required.| **==> picture [59 x 34] intentionally omitted <==** **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 17 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 |NB|||N/A||Bias Winding number of turns| |---|---|---|---|---|---| |REXT|||N/A|k-ohm|Suggested value of BYPASS pin<br>resistor(use standard 5%resistor)| |**DESIGN PARAMETERS**|||||| |DCON|4.6||4.60|us|Output diode conduction time| |TON|||3.72|us|LinkSwitch-II On-time (calculated at<br>minimum inductance)| |RUPPER|||47.11|k-ohm|Upper resistor in Feedback resistor<br>divider| |RLOWER|||8.89|k-ohm|Lower resistor in resistor divider| |**ENTER TRANSFORMER CORE/CONSTRUCTION VARIABLES**|||||| |Core Type|||||| |Core|EE13||EE13||Enter Transformer Core. Based on the<br>output power the recommended core<br>sizes are EE16 or EE19| |Bobbin|||EE13_BOBBIN||Generic EE13_BOBBIN| |AE|||17.10|mm^2|Core Effective Cross Sectional Area| |LE|||30.20|mm^2|Core Effective Path Length| |AL|||1130.00|nH/turn^2|Ungapped Core Effective Inductance| |BW|||7.90|mm|Bobbin Physical Winding Width| |M|||0.00|mm|Safety Margin Width (Half the Primary<br>to SecondaryCreepage Distance)| |L|2||2.00||Number of Primary Layers| |NS|||16.00||Number of Secondary Turns. To adjust<br>Secondary number of turns change<br>DCON| |**DC INPUT VOLTAGE PARAMETERS**|||||| |VMIN|||78.44|V|Minimum DC bus voltage| |VMAX|||374.77|V|Maximum DC bus voltage| ||||||| |**CURRENT WAVEFORM SHAPE PARAMETERS**|||||| |DMAX|||0.30||Maximum duty cycle measured at<br>VMIN| |IAVG|||0.07|A|Input Average current| |IP|||0.30|A|Peak primary current| |IR|||0.30|A|Primary ripple current| |IRMS|||0.11|A|Primary RMS current| |**TRANSFORMER PRIMARY DESIGN PARAMETERS**|||||| |LPMIN|||975.96|uH|Minimum Primary Inductance| |LPTYP|||1084.40|uH|Typical Primary inductance| |LP_TOLERANCE|||10.00|%|Tolerance in primary inductance| |NP|||80.00||Primary number of turns. To adjust<br>Primary number of turns change<br>BM_TARGET| |ALG|||169.44|nH/turn^2|Gapped Core Effective Inductance| |BM_TARGET|2470||2470.00|Gauss|Target Flux Density| |BM|||2457.33|Gauss|Maximum Operating Flux Density<br>(calculated at nominal inductance), BM<br>< 2500 is recommended| |BP||Warning|3021.33|Gauss|!!! Warning. Peak Flux density exceeds<br>3000 Gauss and is not recommended.<br>Reduce BP byincreasingNS| |BAC|||1228.67|Gauss|AC Flux Density for Core Loss Curves<br>(0.5 X Peak to Peak)| **==> picture [59 x 34] intentionally omitted <==** ## **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 18 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG |ur|||158.81||Relative Permeability of Ungapped<br>Core| |---|---|---|---|---|---| |LG|||0.12|mm|Gap Length (LG > 0.1 mm)| |BWE|||15.80|mm|Effective Bobbin Width| |OD|||0.20|mm|Maximum Primary Wire Diameter<br>includinginsulation| |INS|||0.04||Estimated Total Insulation Thickness<br>(= 2 * film thickness)| |DIA|||0.16|mm|Bare conductor diameter| |AWG|||35.00||Primary Wire Gauge (Rounded to next<br>smaller standard AWG value)| |CM|||32.00|Cmils|Bare conductor effective area in<br>circular mils| |CMA|||293.06|Cmils/A|Primary Winding Current Capacity (200<br>< CMA < 500)| |**TRANSFORMER SECONDARY DESIGN PARAMETERS**|||||| |Lumped parameters|||||| |ISP|||1.50|A|Peak Secondary Current| |ISRMS|||0.61|A|Secondary RMS Current| |IRIPPLE|||0.53|A|Output Capacitor RMS Ripple Current| |CMS|||122.33|Cmils|Secondary Bare Conductor minimum<br>circular mils| |AWGS|||29.00||Secondary Wire Gauge (Rounded up<br>to next larger standard AWG value)| |**VOLTAGE STRESS PARAMETERS**|||||| |VDRAIN|||526.02|V|Maximum Drain Voltage Estimate<br>(Assumes 20% clamping voltage<br>tolerance and an additional 10%<br>temperature tolerance)| |PIVS|||86.95|V|Output Rectifier Maximum Peak<br>Inverse Voltage| |**FINE TUNING**|||||| |RUPPER_ACTUAL|||47.11|k-ohm|Actual Value of upper resistor<br>(RUPPER)used on PCB| |RLOWER_ACTUAL|||8.89|k-ohm|Actual Value of lower resistor<br>(RLOWER)used on PCB| |Actual (Measured) Output Voltage (VDC)|||12.00|V|Measured Output voltage from first<br>prototype| |Actual (Measured) Output Current (ADC)|||0.30|Amps|Measured Output current from first<br>prototype| |RUPPER_FINE|||47.11|k-ohm|New value of Upper resistor<br>(RUPPER) in Feedback resistor<br>divider. Nearest standard value is 47.5<br>k-ohms| |RLOWER_FINE|||8.89|k-ohm|New value of Lower resistor<br>(RLOWER) in Feedback resistor<br>divider. Nearest standard value is 8.87<br>k-ohms| Note: The BP (peak flux density) warning in the spreadsheet was mitigated by verifying the drain current waveforms and confirming that there was no core saturation. **==> picture [59 x 34] intentionally omitted <==** **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 19 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ## **9 Performance Data** All measurements performed at room temperature. ## _**9.1 Efficiency vs. Line and Output Voltage**_ |**Hz**|**VIN**<br>**(VAC)**|**PIN**<br>**(W)**|**VOUT**<br>**(V)**|**IOUT**<br>**(mA)**|**POUT**<br>**(W)**|**Efficiency**<br>**(%)**| |---|---|---|---|---|---|---| |50|90|4.832|12.16|300|3.648|75.5| |50|100|4.78|12.16|300|3.648|76.32| |50|115|4.736|12.16|300|3.648|77.03| |50|130|4.704|12.13|300|3.639|77.36| |**Hz**|**VIN**<br>**(VAC)**|**PIN**<br>**(W)**|**VOUT**<br>**(V)**|**IOUT**<br>**(mA)**|**POUT**<br>**(W)**|**Efficiency**<br>**(%)**| |50|185|4.752|12.13|300|3.639|76.58| |50|200|4.768|12.12|300|3.636|76.26| |50|215|4.79|12.1|300|3.63|75.78| |50|230|4.826|12.1|300|3.63|75.22| |50|245|4.849|12.1|300|3.63|74.86| |50|265|4.902|12.1|300|3.63|74.08| **==> picture [59 x 34] intentionally omitted <==** **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 20 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## _**9.2 No-Load Power Consumption**_ **==> picture [424 x 253] intentionally omitted <==** **----- Start of picture text -----**<br> 50<br>Io = 0 mA<br>45<br>40<br>35<br>30<br>25<br>20<br>85 105 125 145 165 185 205 225 245 265<br>Input Voltage (VAC)<br>Input Power (mW)<br>**----- End of picture text -----**<br> **Figure 7** – No-load Power Consumption, Room Temperature. **==> picture [59 x 34] intentionally omitted <==** **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 21 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ## _**9.3 Output Characteristic**_ **==> picture [177 x 70] intentionally omitted <==** **----- Start of picture text -----**<br> Auto-restart<br>Region<br>0<br>0<br>**----- End of picture text -----**<br> **Figure 8** – CC/CV Curve at 90 VAC Input, Room Temperature. **==> picture [178 x 76] intentionally omitted <==** **----- Start of picture text -----**<br> Auto-restart<br>Region<br>0<br>0<br>**----- End of picture text -----**<br> **Figure 9** – CC/CV Curve at 120 VAC Input, Room Temperature. **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 22 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG **==> picture [184 x 71] intentionally omitted <==** **----- Start of picture text -----**<br> Auto-restart<br>Region<br>0<br>0<br>**----- End of picture text -----**<br> **Figure 10** – CC/CV Curve at 230 VAC Input, Room Temperature. **==> picture [186 x 79] intentionally omitted <==** **----- Start of picture text -----**<br> Auto-restart<br>Region<br>0<br>0<br>**----- End of picture text -----**<br> **Figure 11** – CC/CV Curve at 265 VAC Input, Room Temperature. **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 23 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ## **10 Thermal Performance** ## _**10.1 Measurement with Infrared Camera (Open Frame)**_ Images captured after running 30 minutes at room temp (25°C), full load indicates a LinkSwitch-II device plastic temperature rise of 30°C over ambient. The addition of a small copper heatsink (6 x 12) mm next to the device reduces device operating temperature. ## 10.1.1 VIN = 115 VAC **Figure 12** – Top Side. **Figure 13** – Bottom Side. ## 10.1.2 VIN = 230 VAC **Figure 14** – Top Side. **Figure 15** – Bottom Side. **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 24 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## _**10.2 Measurement with Thermocouples (Inside Enclosure)**_ The completed driver had thermocouples attached to key components when inserted into a GU10 housing. The unit was operated with a case external ambient of 70°C and allowed to reach thermal equivalent before readings were recorded. The measured component temperatures are in the table below. |**Component Temperature Measurement**|**Component Temperature Measurement**|**Component Temperature Measurement**| |---|---|---| |**(Under a TA of 70 ºC outside the case external)**||| ||**Input:90 VAC,**<br>**TA=70ºC**|**Input:264 VAC,**<br>**TA=70ºC**| |U1(LNK605DG)|112.0|115.0| |T1(winding)|96.1|97.0| |T1(core)|101.1|102.5| |D3(SS110)|94.7|94.9| |C1(3.3F / 400 V)|92.9|91.0| |C2(3.3F / 400 V)|93.3|91.6| **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 25 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ## **11 Waveforms** ## _**11.1 Drain Voltage and Current**_ **Figure 16** – 90 VAC, Full Load. Lower: IDRAIN, 0.2 A / div. Upper: VDRAIN, 200 V, 5 s / div. **Figure 17** – 265 VAC, Full Load. Lower: IDRAIN, 0.2 A / div. Upper: VDRAIN, 200 V / div., 5 s / div. ## _**11.2 Drain Voltage and Current Start-up Profile**_ **==> picture [9 x 10] intentionally omitted <==** **----- Start of picture text -----**<br> `<br>**----- End of picture text -----**<br> **Figure 18** – 90 VAC, Full Load. Lower: IDRAIN, 0.2 A / div. Upper: VDRAIN, 200 V, 5ms/ div. **Figure 19** – 265 VAC, Full Load. Lower: IDRAIN, 0.2 A / div. Upper: VDRAIN, 200 V, 5ms/ div. **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 26 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## **12 Line Surge** Differential ring wave testing was completed on a single test unit, according to EN61000-4-5. Input voltage was set at 230 VAC / 50 Hz. Output was loaded at full load and operation was verified following each surge event. |**Surge Level**<br>**(V)**|**Input Voltage**<br>**(VAC)**|**Injection**<br>**Location**|**Injection Phase**<br>**(°)**|**Test Result**<br>**(Pass/Fail)**| |---|---|---|---|---| |1000|230|L to N|0|Pass| |1000|230|L to N|90|Pass| |1000|230|L to N|180|Pass| |1000|230|L to N|270|Pass| |2000|230|L to N|0|Pass| |2000|230|L to N|90|Pass| |2000|230|L to N|180|Pass| |2000|230|L to N|270|Pass| **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 27 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ## **13 Hipot Test** The power supply passed a 3 kV AC Hipot test. The potential was applied from the positive terminal of the bridge rectifier to both output terminals (output terminals were shorted together). The potential was applied for 10 seconds. ## **14 ESD Test** **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 28 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## **15 Conducted EMI** Note: Blue line is a peak measurement compared against quasi peak limit line. This represents a very conservative measurement method as actual quasi peak measurements are typically 2-3 dB lower than peak. **Figure 20** – Conducted EMI, Maximum Steady State Load, 115 VAC, 60 Hz, and EN55015B Limits. Line **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 29 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 **Figure 21** – Conducted EMI, Maximum Steady State Load, 115 VAC, 60 Hz, and EN55015B Limits. Neutral **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 30 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG **Figure 22** – Conducted EMI, Maximum Steady State Load, 230 VAC, 60 Hz, and EN55015B Limits **.** Line **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 31 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 **Figure 23** – Conducted EMI, Maximum Steady State Load, 230 VAC, 60 Hz, and EN55015B Limits **.** Neutral **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 32 of 34 24-Sept-10 DER-261 3.6 W GU10 LED Driver Using LNK605DG ## **16 Revision History** |**Date**|**Author**|**Revision**|**Description & changes**|**Reviewed**| |---|---|---|---|---| |24-Sep-10|TH/JY|1.5|Initial Release|Apps and Mktg| |||||| |||||| |||||| |||||| **==> picture [59 x 34] intentionally omitted <==** **Power Integrations** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 33 of 34 DER-261 3.6 W GU10 LED Driver Using LNK605DG 24-Sept-10 ## **For the latest updates, visit our website: www.powerint.com** Power Integrations reserves the right to make changes to its products at any time to improve reliability or manufacturability. Power Integrations does not assume any liability arising from the use of any device or circuit described herein. POWER INTEGRATIONS MAKES NO WARRANTY HEREIN AND SPECIFICALLY DISCLAIMS ALL WARRANTIES INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT OF THIRD PARTY RIGHTS. ## **PATENT INFORMATION** The products and applications illustrated herein (including transformer construction and circuits external to the products) may be covered by one or more U.S. and foreign patents, or potentially by pending U.S. and foreign patent applications assigned to Power Integrations. A complete list of Power Integrations’ patents may be found at www.powerint.com. Power Integrations grants its customers a license under certain patent rights as set forth at http://www.powerint.com/ip.htm. The PI Logo, TOPSwitch, TinySwitch, LinkSwitch, DPA-Switch, PeakSwitch, EcoSmart, Clampless, E-Shield, Filterfuse, StackFET, PI Expert and PI FACTS are trademarks of Power Integrations, Inc. Other trademarks are property of their respective companies. ©Copyright 2010 Power Integrations, Inc. ## **Power Integrations Worldwide Sales Support Locations** ## **WORLD HEADQUARTERS** 5245 Hellyer Avenue San Jose, CA 95138, USA. Main: +1-408-414-9200 Customer Service: Phone: +1-408-414-9665 Fax: +1-408-414-9765 _e-mail: usasales@powerint.com_ ## **GERMANY** Rueckertstrasse 3 D-80336, Munich Germany Phone: +49-89-5527-3911 Fax: +49-89-5527-3920 _e-mail: eurosales@powerint.com_ ## **JAPAN** ## **TAIWAN** Kosei Dai-3 Building 5F, No. 318, Nei Hu Rd., Sec. 1 2-12-11, Shin-Yokohama, Nei Hu District Kohoku-ku, Yokohama-shi, Taipei 114, Taiwan R.O.C. Kanagawa 222-0033 Phone: +886-2-2659-4570 Japan Fax: +886-2-2659-4550 Phone: +81-45-471-1021 _e-mail:_ Fax: +81-45-471-3717 _taiwansales@powerint.com e-mail: japansales@powerint.com_ ## **CHINA (SHANGHAI)** ## **INDIA** Rm 1601/1610, Tower 1 #1, 14[th] Main Road Kerry Everbright City Vasanthanagar No. 218 Tianmu Road West Bangalore-560052 Shanghai, P.R.C. 200070 India Phone: +86-021-6354-6323 Phone: +91-80-4113-8020 Fax: +86-021-6354-6325 Fax: +91-80-4113-8023 _e-mail: e-mail: chinasales@powerint.com indiasales@powerint.com_ ## **KOREA** RM 602, 6FL Korea City Air Terminal B/D, 159-6 Samsung-Dong, Kangnam-Gu, Seoul, 135-728 Korea Phone: +82-2-2016-6610 Fax: +82-2-2016-6630 _e-mail: koreasales@powerint.com_ ## **UNITED KINGDOM** 1st Floor, St. James’s House East Street, Farnham Surrey, GU9 7TJ United Kingdom Phone: +44 (0) 1252-730-141 Fax: +44 (0) 1252-727-689 _e-mail: eurosales@powerint.com_ **CHINA (SHENZHEN)** Rm A, B & C 4[th] Floor, Block C, Electronics Science and Technology Building 2070 Shennan Zhong Road Shenzhen, Guangdong, P.R.C. 518031 Phone: +86-755-8379-3243 Fax: +86-755-8379-5828 _e-mail: chinasales@powerint.com_ ## **ITALY** Via De Amicis 2 20091 Bresso MI Italy Phone: +39-028-928-6000 Fax: +39-028-928-6009 _e-mail: eurosales@powerint.com_ ## **SINGAPORE** 51 Newton Road, #15-08/10 Goldhill Plaza Singapore, 308900 Phone: +65-6358-2160 Fax: +65-6358-2015 _e-mail: singaporesales@powerint.com_ ## **APPLICATIONS HOTLINE** World Wide +1-408-414-9660 ## **APPLICATIONS FAX** World Wide +1-408-414-9760 **==> picture [59 x 34] intentionally omitted <==** **Power Integrations, Inc.** Tel: +1 408 414 9200 Fax: +1 408 414 9201 www.powerint.com Page 34 of 34
Updated at April 28, 2026
Power Integrations is a leading innovator in semiconductor technologies dedicated to high-voltage power conversion. Renowned for advancing the clean-power ecosystem, the company designs highly integrated chips that maximize energy efficiency across a vast range of consumer and industrial applications. Through proprietary advancements like PowiGaN gallium-nitride technology and EcoSmart energy-efficiency solutions, their components deliver exceptional performance while significantly reducing global energy waste. A major focus of their product lineup includes discrete semiconductors, particularly fast and ultrafast recovery rectifier diodes. These essential components provide the high-speed switching and exceptional reliability required for modern power supply designs. By minimizing power loss and thermal output, they ensure efficient power transmission in demanding, high-efficiency circuit environments. Furthermore, Power Integrations is a premier manufacturer of specialized LED lighting components. Their advanced AC/DC LED driver ICs offer engineers streamlined, energy-efficient solutions for solid-state lighting applications. By integrating critical control and protection features into a single footprint, these drivers reduce the overall component count and accelerate the development of reliable, high-performance commercial and consumer lighting systems.
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