Francesco Truzzi just announced a really great ATX PSU break-out board. It can act as a USB charger, has a variable voltage output and a set of fixed voltage levels (3.3, 5 and 12v). The design is based around an open hardware design from dangerous prototypes, this is a real improvement.
Francesco summarizes the board like this:
- It has a 24-pin ATX connector.
- Voltage lines are all broken out individually on binding posts.
- LM317-based voltage regulator. Using a 300 ohm resistor and a 2K ohm potentiometer, voltage range is 1.25-9V.
- 2 USB ports based on the TPS2513 from Texas Instruments. They can automatically detect what device is connected and adjust resistance on D+ and D- lines as needed. This means full compatibility and maximum charging speed on both Apple and Android devices. One of them is connected to 5v_STDBY, so that it works even when the PSU is off.
- Pretty much everything can be fused. I left -12V out because it can only carry low amounts of current on most PSUs (mine is 500mA maximum).
- Breadboard pin headers so that voltage lines can be connected to a breadboard using jumper cables.
- Voltmeter headers in order to know the LM317 output voltage.
- There is room for a 9W power resistor is your PSU needs it to stabilize output voltages. You can connect it either to the 5v rail or to the 12v one by jumpering the corresponding pads.
- Status LEDs on fused lines and USBs so you can check if everything works fine.
- Screw holes for standoffs.
- Breaking Bad art because yeah, this is science, bitch.
Via dangerous prototypes.