DER-43

24.5 W Telecom Line Card PSU

November 18, 2004

Table Of Contents

1

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

2

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

3

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

4

Circuit Operation.........................................................................................................6

4.1

General................................................................................................................6

4.2

Description...........................................................................................................6

5

BOM............................................................................................................................7

6

Layout .........................................................................................................................8

7

Transformer Design Spreadsheet...............................................................................9

8

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

8.1

Transformer Winding .........................................................................................11

8.2

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

8.3

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

8.4

Transformer Build Diagram................................................................................12

8.5

Transformer Construction ..................................................................................12

9

Efficiency ..................................................................................................................13

10

Regulation vs. Load...............................................................................................14

11

Low Load Power Consumption .............................................................................15

12

Drain Voltage and Current Waveforms..................................................................16

13

Transient Load ......................................................................................................17

13.1 Transient Load Test Setup ................................................................................17

13.2 Transient Load Performance .............................................................................18

14

Output Ripple ........................................................................................................19

14.1 Output Ripple Measurement Technique ............................................................19

14.2 Full Load Ripple Performance ...........................................................................20

14.3 No Load Ripple Performance ............................................................................20

15

Other results..........................................................................................................21

16

Revision History ....................................................................................................22

Important Note:

This board is designed to be non-isolated. Please take necessary safety precautions.

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.

Page 2 of 23

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