DER-62

3W Charger using LNK363P

August 24, 2005

Page 2 of 24

Power Integrations

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Table Of Contents

1

Introduction ................................................................................................................ 4

2

Power Supply Specification........................................................................................ 4

3

Schematic .................................................................................................................. 5

3.1

With RCD clamp ................................................................................................. 5

3.2

With Zener clamp and bias winding .................................................................... 5

4

PCB............................................................................................................................ 6

5

Bill Of Materials—RCD clamp .................................................................................... 6

6

Transformer Specification .......................................................................................... 7

6.1

Electrical Diagram............................................................................................... 7

6.2

Electrical Specifications ...................................................................................... 7

6.3

Materials ............................................................................................................. 7

6.4

Transformer Build Diagram ................................................................................. 8

6.5

Transformer Construction ................................................................................... 8

7

Transformer Spreadsheets ........................................................................................ 9

8

Performance Data .................................................................................................... 11

8.1

Efficiency vs CEC ............................................................................................. 11

8.1.1

With RCD Clamp, no bias winding ............................................................. 11

8.1.2

With Zener Clamp and Bias winding .......................................................... 12

8.2

Efficiency vs Input Voltage ................................................................................ 12

8.2.1

With RCD clamp, no bias winding.............................................................. 12

8.2.2

With zener clamp and bias winding ........................................................... 13

8.3

No-Load Input Power ........................................................................................ 13

8.3.1

RCD clamp, no bias winding...................................................................... 13

8.3.2

Zener clamp clamp and bias winding......................................................... 14

8.4

Output Regulation ............................................................................................. 14

8.5

Thermal Performance ....................................................................................... 15

8.5.1

Thermal testing set up ............................................................................... 15

8.5.2

Test results of RCD clamp ......................................................................... 15

8.5.3

Thermal performance of Zener clamp and bias winding. ........................... 15

9

Waveforms............................................................................................................... 16

9.1

Drain Voltage, Normal Operation ...................................................................... 16

9.2

Drain Voltage During Startup ............................................................................ 17

9.3

Output Voltage Start-up Profile ......................................................................... 17

10

Output Ripple Measurements ............................................................................... 18

10.1.1

Ripple Measurement Technique ................................................................ 18

10.1.2

Measurement Results ................................................................................ 20

11

Conducted EMI..................................................................................................... 21

12

Transformer construction with bias winding.......................................................... 22

12.1

Electrical Diagram............................................................................................. 22

12.2

Transformer Build Diagram ............................................................................... 22

13

Revision History.................................................................................................... 23