Compact ATX Breakout Board

It sucks when you need 12 VDC and your power supply just died.  Previously we made an ATX breakout board to turn an ATX power supply into a fixed voltage bench DC power supply.  Here we present a board that is designed to be smaller and for use as a backup.

Computer to 12 VDC supply conversion board

This little board is geared towards those in the amateur radio community that are into emergency communications and have their own personal “bag of tricks” that they take with them wherever they go.  It’s a compact PC to Switching DC power supply board.  It’s got just enough real estate for the connectors.  It’s designed to power up the power supply as soon as the 20/24 pin ATX header is plugged in (PS_ON# shorted to ground).  There are separate connectors and circuits for drawing power off the 12V auxiliary connector (4 or 8 pin connection), PCI-E auxiliary power (6 or 8 pin) and from standard ATX peripheral connector.  This allows the board to run a full ATX power supply or to serve as adapters for unused connectors in a computer.  RF blocking capacitors were added to the PCI-E and ATX peripheral connectors as they are the ones that might be used simultaneously with a computer.

Top view of ATX power supply conversion board

Here are the Gerbers and the Bill of Materials: