The Lab Power Supply That Fits in Your Pocket

A power supply is perhaps the most important tool in any electronics hobbyist’s toolbox, yet the details of these essential components are often overlooked. While many beginners focus on the microcontrollers or sensors at the heart of their projects, the quality of the power driving them determines the stability and longevity of the entire circuit. Furthermore, as circuits grow more complex, a "noisy" power supply can introduce phantom bugs that are nearly impossible to track down.

When we leave our home labs and go on the road, these issues tend to be magnified. Rather than lugging around our bench power supplies, most of us will whip out a phone charger and call it good. But we don’t actually need to compromise so much for portability. Consider Ampisu, for instance. It is a full‑featured lab power supply that is small enough to fit in your pocket.

Ampisu measures just 62 × 62 × 19 millimeters and weighs 110 grams, making it small enough to throw into a backpack, yet it offers capabilities normally associated with much larger lab instruments. The device provides three fully isolated outputs, two of which are programmable from 0 to 7.5 volts at up to 500 milliamps each, along with a dedicated 3.3-volt auxiliary rail for logic or sensors.

Performance and safety are central to the design of the device. Ampisu features fast, fine-grained analog current limiting to protect circuits during first power-on, precise voltage and current measurement, and low-noise linear post-regulation. Full galvanic isolation between the USB host and the outputs further reduces the risk of ground loops or accidental damage.

Power and communication are handled over a single USB connection, with the device automatically adapting to the capabilities of the host. It works out of the box on Windows, Linux, and macOS without drivers, and can be controlled via standard SCPI commands, a Python API, or a built-in web interface. This programmability makes Ampisu well suited for automated testing, voltage sweeps, and even integration into CI or production test setups.

Ampisu will soon be launching on Crowd Supply, so be sure to sign up for notifications if you are interested. Following the crowdfunding campaign, the device’s schematics, firmware, and software will be released under permissive licenses, ensuring transparency, hackability, and long-term maintainability.