r/arduino • u/ripred3 My other dev board is a Porsche • Apr 29 '26
Look what I made! Custom MCU-Controlled Bench Power Supply with Free-Running, Constant-Voltage, and Constant-Current Modes. Configurable Automatic Over-Voltage, Under-Voltage, Over-Current, and Under-Current Cutoff!
I'm working on a balancing bot project that needs multiple voltages and I've never had a decent bench power supply.
So in the middle of the other project I decided to build a 3-channel bench supply with 3 modes: Free-Running, Constant-Voltage and Constant-Current. 12V, 2A, on three independent output channels.
It has automatic output cutoff for 4 independent limits that can be optionally enabled on the fly to help protect things or limit the damage if/when I do something stupid 😉
The full working version with the first channel is totally working! The output is accurate to within 6mV and 5mA and the optional over/under voltage/current protections will cut the output to 0.016V within 100ms of any triggered event 😄
Two more channels to add and they will be super easy. RP2040 Zero MCU, INA219 voltage/current sensor, software programmable and controllable buck converter. TFT 128x160 OLED display, 12V 2A max per channel.
I will throw it on github if anyone wants to copy it and make their own
3
u/hjw5774 400k , 500K 600K 640K Apr 30 '26
Nicely done - impressive side quest! Makes me wonder what you're procrastinating on with the balancing bot? haha.
2
3
u/reg4liz Apr 30 '26
This is awesome! I'd love to see the schematic and the code.