EPR-31 Datasheet, PDF (3/36 Pages) Power Integrations, Inc. – Engineering Prototype Report for EP-31 Multiple Output 180 W AC-DC Power

01-Feb-05
EPR-31 – Multi-Output, 180 W, PC Main Power Supply
1 Introduction
This engineering report describes the operation and provides performance data
for a 180 W forward converter-based PC mains supply (using TOPSwitch-GX),
and a 10 W flyback converter-based PC standby supply (using TinySwitch-II).
This design is intended to demonstrate the viability of the TOPSwitch-GX in a PC
main application, in a micro-ATX enclosure, with passive PFC. Because many of
the functions necessary for a forward converter are integrated into the
TOPSwitch-GX family of power conversion ICs, designing around it reduces the
PCB area required for the layout of the main converter.
A supervisory ASIC was not included. However, a simple circuit (see Figure 5)
was implemented to demonstrate the remote ON/OFF and fault latching
operation that an ASIC normally performs. The 3.3 V output does not have
remote voltage sensing, but using standard techniques this could easily be
added.
This report contains power supply specifications, bills of material (BOM), circuit
diagrams, custom magnetic components documentation (transformers, output
inductor and mag-amp inductor), PCB layouts, and pertinent electrical test data.
Figure 1 – Photograph of the populated circuit boards of the EP-31 prototype.
Page 3 of 36
Power Integrations
Tel: [phone] Fax: [phone]
www.powerint.com