Stefan Wagner's USB PD Tester Is a Tiny Power Supply Gadget Built Around a RISC-V Microcontroller

Offering USB Power Delivery and Programmable Power Supply support, this compact tester doubles as a benchtop power supply.

Gareth Halfacree
5 months agoHW101 / 3D Printing

Maker Stefan Wagner has designed a tool for testing USB Power Delivery (PD) and Programmable Power Supply (PPS) power supplies and cables, offering a simple USB Type-C connection at one end and doubling as a handy benchtop power supply: the USB PD Tester.

"The USB PD Tester is a monitoring and triggering device designed for USB Power Delivery," Wagner explains. "It allows you to test a wide range of USB Type-C PD power supplies and their corresponding cables.

"This tool not only displays the capabilities of the power supply on an OLED but also enables you to select one of the available fixed or programmable voltages for output on the screw terminal. With this, it can also be used to power your projects with various selectable voltages and high currents, serving as a versatile variable power supply."

This compact board can test your USB PD supplies and cables — or deliver programmable power to your projects. (📹: Stefan Wagner)

The compact board is designed to be simple to use: a USB Type-C connector links the tester to the power supply, which boots and displays the available USB Power Delivery modes on its OLED panel — voltage and maximum current.

In addition to the USB Power Delivery modes available, the gadget can also request the newer USB Programmable Power Supply mode — with user-set voltage and current limits. Regardless of the mode used, the chosen supply is passed through to screw terminals at the far end — ready for use by external hardware.

A key feature of the USB PD Tester is that it's built around the WCH Electronics CH32X035, a low-cost 32-bit microcontroller that uses the free and open source RISC-V instruction set architecture. Despite being available in small-order quantity for around 30¢ a chip, the microcontroller also offers USB 2.0 and USB Power Delivery support — reducing the number of components required to build the tester.

Design files, firmware, and a 3D-printable case for the USB PD Tester are available on Wagner's GitHub repository under the Creative Commons Attribution-ShareAlike 3.0 Unported license.

Gareth Halfacree
Freelance journalist, technical author, hacker, tinkerer, erstwhile sysadmin. For hire:
Latest articles
Sponsored articles
Related articles
Latest articles
Read more
Related articles