RDR-83 7.7 V, 210 mA Adapter with 10 kV surge withstand

29-Sept-06

Page 2 of 36

Power Integrations

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Table Of Contents

1

Introduction.................................................................................................................3

2

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

2.1

Typical Output Characteristic and limits ..............................................................5

3

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

4

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

4.1

Input Stage ..........................................................................................................7

4.2

LinkSwitch-LP

......................................................................................................7

4.3

Feedback.............................................................................................................8

4.4

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

8

Design Spreadsheets ...............................................................................................14

9

Performance Data ....................................................................................................19

9.1

Efficiency ...........................................................................................................19

9.1.1

Active Mode ENERGY STAR / CEC Efficiency Measurement Data...........20

9.2

No-load Input Power..........................................................................................21

9.3

Available Standby Output Power.......................................................................21

9.4

Regulation .........................................................................................................22

9.4.1

VI Curve vs. Input Voltage..........................................................................22

10

Thermal Performance ...........................................................................................23

10.1 LNK562 Temperature Rise................................................................................23

10.2 Thermal Image ..................................................................................................23

11

Waveforms............................................................................................................24

11.1 Drain Voltage and Current, Normal Operation...................................................24

11.2 Output Voltage Start-up Profile..........................................................................24

11.3 Drain Voltage and Current Start-up Profile ........................................................25

11.4 Load Transient Response (50% to 100% Load Step) .......................................26

11.5 Output Ripple Measurements............................................................................27

11.5.1

Ripple Measurement Technique ................................................................27

11.5.2

Measurement Results ................................................................................28

12

Line Surge.............................................................................................................29

13

Conducted EMI .....................................................................................................30

14

Revision History ....................................................................................................32

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.