DER-48

Dual Output LNK304 Flyback

April 20, 2005

Page 2 of 22

Power Integrations

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Table Of Contents

1

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

2

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

3

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

4

Circuit Description ...................................................................................................... 6

5

PCB Layout ................................................................................................................ 7

6

Bill Of Materials .......................................................................................................... 8

7

Transformer Specification........................................................................................... 9

7.1

Electrical Diagram ............................................................................................... 9

7.2

Electrical Specifications....................................................................................... 9

7.3

Materials.............................................................................................................. 9

7.4

Transformer Build Diagram ............................................................................... 10

7.5

Transformer Construction.................................................................................. 10

7.6

Design Notes..................................................................................................... 11

8

Transformer Spreadsheets....................................................................................... 12

9

Performance Data .................................................................................................... 13

9.1

Cross-Regulation Data ...................................................................................... 13

9.2

No-load Input Power and Efficiency .................................................................. 14

9.3

Regulation ......................................................................................................... 15

9.3.1

Line and Load Regulation .......................................................................... 15

10

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

10.1

Drain Voltage and Current, Normal Operation .................................................. 16

10.2

Output Voltage Start-up Profile ......................................................................... 16

10.3

Drain Voltage and Current Start-up Profile........................................................ 17

10.4

Load Transient Response (50% to 100% Load Step) ....................................... 17

10.5

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

10.5.1

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

10.5.2

Measurement Results ................................................................................ 19

11

Conducted EMI ..................................................................................................... 20

12

Revision History .................................................................................................... 21

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.

Design Reports contain a power supply design specification, schematic, bill of materials,

and transformer documentation. Performance data and typical operation characteristics

are included. Typically only a single prototype has been built.