Overview
This is a power supply for my homebrew Eurorack synthesizer. I used an old laptop charger (power brick) as the AC-DC converter so I didn't have to mess around with mains voltage.
The power supply was meant to live inside the system case, but I never got around to making a proper case. 🙄 It powered an 84 HP tabletop rack until I outgrew that and bought a 6U case with a beefier power supply.
Specs
- Input
- Requires between 9 V and 36 V DC, 35W (from a power brick / wall wart)
- Output
- +12 V, -12 V (1 A each), +5 V (500 mA)
Notes
An AC-DC converter (power brick, wall wart) is required to supply the input voltage (9 V to 36 V DC). I used the charger from an old laptop, which fortunately has an ordinary barrel jack for its DC output and doesn't need any handshake signals from the laptop. (An Apple charger won't work, for example.)
The standard Eurorack voltages (+12 V, -12 V, +5 V) are supplied by switching DC-DC converters. The outputs are isolated from the input.
There are two 16-pin Eurorack power connectors. You'll want a busboard or flying-bus cable to feed multiple modules.
The power supply is assembled on a stripboard PCB. I have provided a layout diagram.
The hardware design files are on GitHub.
Please note that I am a hobbyist, not a trained electronics engineer. No guarantees!
![](schematic.png)
![](stripboard-layout.png)
![](circuit-top.jpg)
![](circuit-bottom.jpg)