EPR-33 Datasheet, PDF (12/32 Pages) Power Integrations, Inc. – Engineering Prototype Report for EP 33 - 45 W LCD Monitor External Power Supply using TOP247Y (TOPSwitch-GX)

EPR-33 – 45 W External Adapter Supply
7.3 Transformer Build Diagram
Pins Side
7,8
9,10
5
4
1
3
28-Mar-2003
Secondary
Bias
Primary
Figure 5 - EP-33 Transformer Build Diagram.
7.4 Transformer Construction
1/2 Primary
Start at Pin 3. Wind 16 turns of item [3] in one layer.
Basic Insulation
Apply one layer of item [6] over completed winding layer.
1/2 Primary
Basic Insulation
Trifilar Bias
winding
Basic Insulation
Hexafilar
Secondary Winding
Outer Wrap
Final Assembly
Wind remaining 16 turns, finish on Pin 1.
Apply one layer of item [6] for basic insulation.
Starting at Pin 4, wind 3 trifilar turns of item [4]. Spread turns evenly across
bobbin. Finish at Pin 5.
Use two layers of item [6] for basic insulation.
Start at Pins 9 and 10. Wind 4 hexafilar turns of item [5]. Spread turns evenly
across bobbin. Finish on Pins 7 and 8.
Wrap windings with 3 layers of tape (item [6]).
Assemble and secure core halves. Varnish impregnate (item [7]).
7.5 Transformer Sources
For information on the vendors used to source the transformers used on this board,
please visit the Power Integrations' Web site at the URL below and select “Engineering
Prototype Boards”.
http://www.powerint.com/componentsuppliers.htm
Power Integrations, Inc.
Tel: [phone] Fax: [phone]
www.powerint.com
Page 12 of 32