Eurorack Power Supply

Power supply based on the LM7812 and LM7912 power regulator chips, ideal for smaller cases and workbenches.

Eurorack Power Supply

This Power supply is based on the LM7812 and LM7912 Power regulator chips. The simplicity in its working principle and its low part count makes it an easy build and a cheap yet effective supply to power up smaller cases and workbenches.

Use only an AC output wall wart. DO NOT USE A DC OUTPUT WALL WART. This device is meant to handle small voltages, for safety reasons make sure you never use a power supply outputting more than 15V. Use a wall wart with an output of 300mA to 1000mA. Do not use the supply for more than 1A on the outputs. Also take care when you are picking the voltage regulators, since they have variants with lower output current. Using the 1A versions is recommended.
All capacitors must have working voltage of at least 35V. For electrolytic caps use lead spacing 7.5mm or 5mm. All of the capacitors on this device are polarized, do not connect them backwards, it may permanently destroy them.
Using heatsinks is not a must but it is highly recommended. Do not short the two regulators' heatsinks since they have different voltages on them. If you do not use heatsinks you can make the regulators lay down on the PCB using the provided holes.
Always test your circuit for shorts BEFORE connecting the wall wart. Also confirm the operation (+12V/-12V) before connecting to any modules.
In case you do not use LEDs do not forget to short the pads on the backhand side of the board. For power output you can use a 10 pin Eurorack power connector or a screw terminal. Make sure to isolate all the input and output wires from each other to avoid unwanted shorts.
The module is rated for outputting 1A on both +12V and -12V sides. This is assuming the proper wall wart and regulator ICs are used. If you experience the output voltage dropping consider applying a lower load on the device.

Project is inspired by Ray Wilson, for more information on how this power supply works visit the MFOS website: Wallwart Supply

BOM: Google Docs