DER-37

16W Adapter using TOP245P

April 27, 2004

Page 2 of 32

Power Integrations

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Table Of Contents

1

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

2

Power Supply Specification ........................................................................................ 5

3

Schematic................................................................................................................... 6

4

Circuit Description ...................................................................................................... 7

4.1

Input EMI Filtering ............................................................................................... 7

4.2

Output Rectification ............................................................................................. 7

4.3

Output Feedback................................................................................................. 7

5

PCB Layout ................................................................................................................ 9

6

Bill Of Materials ........................................................................................................ 10

7

Transformer Specification......................................................................................... 11

7.1

Electrical Diagram ............................................................................................. 11

7.2

Electrical Specifications..................................................................................... 11

7.3

Materials............................................................................................................ 12

7.4

Transformer Build Diagram ............................................................................... 13

7.4.1

SHLD Build diagram................................................................................... 13

7.5

Transformer Construction.................................................................................. 14

8

Common Mode Choke ............................................................................................. 15

8.1

Electrical Diagram ............................................................................................. 15

8.2

Electrical Specifications..................................................................................... 15

8.3

Materials............................................................................................................ 15

8.4

Common Mode Choke Build Diagram ............................................................... 16

9

Transformer Spreadsheets....................................................................................... 17

10

Performance Data................................................................................................. 18

10.1

Efficiency........................................................................................................... 18

10.2

No-load Input Power.......................................................................................... 19

10.3

Regulation ......................................................................................................... 19

10.3.1

Load ........................................................................................................... 19

10.3.2

Line ............................................................................................................ 20

10.4

Over Power Protection ...................................................................................... 20

10.5

Leakage Current ............................................................................................... 20

11

Thermal Performance ........................................................................................... 21

11.1

Thermal measurements at max ambient ........................................................... 21

11.2

Thermal margin test .......................................................................................... 21

12

Waveforms............................................................................................................ 22

12.1

Drain Voltage and Current, Normal Operation .................................................. 22

12.2

Output Voltage Start-up Profile ......................................................................... 22

12.3

Drain Voltage and Current Start-up Profile........................................................ 23

12.4

Load Transient Response (75% to 100% Load Step) ....................................... 23

12.5

Output Ripple Measurements............................................................................ 24

12.5.1

Ripple Measurement Technique ................................................................ 24

12.5.2

Measurement Results ................................................................................ 25

13

Control Loop Measurements................................................................................. 26

13.1

115 VAC Maximum Load .................................................................................. 26

13.2

230 VAC Maximum Load .................................................................................. 26