PowerSupply

An Arduino-controlled benchtop power supply

Features

• 3.8 to 19.5 VDC output
• Up to 3A continuous current
• Display voltage or current
• RGB LED knob

Components

• Arduino Pro Mini 328 (5v/16MHz)
• 40W Laptop charger for AC/DC conversion
• Illuminated RGB encoder (Sparkfun COM-10982)
• 7-Segment LED display (x2)
• SN74HC595N 8-bit Shift Register (x2)
• 200Ω resistor (16x)
• MCP41HV51 high voltage digital potentiometer
• 22K resistor (4x for voltage divider)
• ACS712 hall-effect current sensor (Sparkfun BOB-08882)
• Toggle switch, max 15A DC (took this one from a vacuum cleaner)
• 4-contact spring terminal block (Digikey GC400-ND)
• LM2596-based DC buck converter (x2)
• A nifty aluminum box

PCB

Custom PCB schematics designed with CircuitMaker, available here

Planned Improvements

• System check on startup
• Constant-current mode
• Battery charger mode
• Overcurrent protection
• Diode/reverse voltage protection