Kai Geissdoerfer's Ampisu, a Tiny Yet Feature-Packed Programmable Power Supply, Opens Crowdfunding

Nessie Circuits' Kai Geissdoerfer has opened crowdfunding for the Ampisu, a compact pocket-sized benchtop power supply featuring three outputs, a friendly web interface, and Standard Commands for Programmable Instruments (SCPI) and Python automation capabilities.

"Ampisu is a full‑featured lab power supply small enough to fit in your pocket, without compromising on precision, safety, or flexibility," Geissdoerfer claims of his creation. "Designed for engineers, makers, and educators, Ampisu is portable enough to carry to the field and precise enough to replace a bench supply for low-power embedded work. With three isolated outputs, fast and precise analog current limiting, and low‑noise linear post‑regulation, Ampisu is equally at home powering a first breadboard experiment, protecting a freshly assembled PCB, or supplying sensitive analog circuitry."

The Ampisu will easily slip into a pocket, but includes two programmable channels with outputs from zero to 7.5VDC at up to 500mA with a third "auxiliary channel" at a fixed 3.3V supporting up to 100mA. If that's not enough, you can combine the two main channel in parallel to support loads up to 1A or in series to support voltages up to 15V or ±7.5V. The input, meanwhile, comes from a USB Type-A or Type-C port — meaning it can run entirely from your laptop, no mains adapter required.

The programmable side of the power supply is handled via an on-board web interface, running in-browser without the need to install any software. This provides full control over both channels, plus live voltage and current monitoring. For automation, the system can talk Standard Commands for Programmable Instruments (SCPI) — or there's a Python application programming interface (API) if you'd prefer. There's an interesting bonus feature, too: the ability to upload a CSV file and have the power output cycle through its values automatically — "similar to an arbitrary waveform generator for power," Geissdoerfer explains.

The project is currently funding on Crowd Supply with hardware priced at $179; schematics, firmware sources, the Python library, and source code for the web interface will be published under unspecified "permissive open-source licenses" following the successful closure of the campaign, Geissdoerfer promises. All hardware is expected to ship at the end of August this year, though as always with crowdfunding campaigns this is a plan rather than a guarantee.