EPR-29 – 4 Output, 11 W, Universal Input, DVD Supply

07-July-03

Page 2 of 36

Power Integrations, Inc.

Tel: +1 408 414 9200 Fax: +1 408 414 9201

www.powerint.com

Table Of Contents

1

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

2

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

3

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

4

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

4.1

Input EMI Filtering............................................................................................... 6

4.2

TinySwitch-II Primary .......................................................................................... 6

4.3

Output Rectification............................................................................................. 6

4.4

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

5

PCB Layout................................................................................................................ 8

6

Bill Of Materials .......................................................................................................... 9

7

Transformer Specification ........................................................................................ 10

7.1

Electrical Diagram............................................................................................. 10

7.2

Electrical Specifications .................................................................................... 10

7.3

Materials ........................................................................................................... 11

7.4

Transformer Build Diagram ............................................................................... 11

7.5

Copper Foil Preparation .................................................................................... 12

7.6

Winding Instructions.......................................................................................... 12

8

Transformer Spreadsheet ........................................................................................ 14

9

Performance Data .................................................................................................... 17

9.1

Efficiency........................................................................................................... 17

9.2

No-load Input Power ......................................................................................... 17

9.3

Standby Input Power......................................................................................... 18

9.4

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

9.4.1

Load Regulation......................................................................................... 19

9.4.2

Line Regulation.......................................................................................... 22

10

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

11

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

11.1

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

11.2

Output Voltage Start-up Profiles ....................................................................... 24

11.2.1

Start-up Profile for 3.3 V and 5 V Outputs.................................................. 24

11.3

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

11.4

Load Transient Response (75% to 100% Load Step) ....................................... 26

11.4.1

Transient Response for 3.3 V and 5 V Outputs ......................................... 26

11.4.2

Transient Response for +12 V and –12 V Outputs .................................... 27

11.5

Output Ripple Measurements ........................................................................... 28

11.5.1

Ripple Measurement Technique ................................................................ 28

11.5.2

Ripple Measurements at 115 VAC............................................................. 29

11.5.3

Ripple Measurements at 230 VAC............................................................. 30

11.6

Conducted EMI ................................................................................................. 31

12

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

Important Note:

Although the EP-29 board is designed to satisfy safety isolation requirements, this 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.