XIAO Powerbread is a breadboard power supply and meter based on XIAO RP2040 or ESP32 USB-C board

The XIAO Powerbread is a breadboard power supply and meter compatible with XIAO RP2040 or ESP32 USB-C boards and equipped with a color LCD display showing real-time voltage, current, and power consumption for 5V and/or 3.3V power rails.

Breadboard power supplies are nothing new. We’ve written about several over the years including the Toaster board with adjustable voltage from 5 to 16V, the SwitchTrick switching power supply board, and the MEGO portable breadboard power supply with a built-in battery. The XIAO Powerbread only supports 5V and 3.3V power rails, but its main selling point is its integrated breadboard power meter function.

XIAO Powerbread specifications:

Supported USB-C modules
- General purpose MCU – XIAO RP2040, XIAO RP2350
- WiFi / Bluetooth MCU – XIAO ESP32S3, XIAO ESP32C3, XIAO ESP32C6
Display – 0.96-inch color TFT LCD with 160×80 resolution and ST7735S SPI controller
Power monitoring – 2x TI INA3221 sensors connected over I2C for voltage, current, and power monitoring
Breadboard pins
- 4x 5V pins
- 4x 3.3V pins
- 10x GND pins
- Tx/Rx UART and 2x GPIOs
Misc
- Power output switch for 3.3V and 5V outputs
- Dial wheel switch for UI rotation and menu selection
Power Supply
- Input – 5V DC via USB-C port on XIAO module
- Output via breadboard-compatible pins
  - 5V up to 1.5A
  - 3.3V up to 1.5A
- MT7900 power switch with 1.5A over current protection
- TI TPS54202DDCR DC-DC step-down convertor up to 3.3V @ 1.5A output
Dimensions – Breadboard compatible

The PCB schematics and PCB layout and the Arduino firmware can be found on GitHub. The developer – Nicho Deng – also released pre-built images for all five support XIAO modules which can be found on the same repository.

The user interface can show both Channel A (5V) and Channel B (3.3V) in monitor mode, or one channel with a chart in “Line-Chart” mode and one channel and extra info in Statistic mode. It’s also possible to rotate the display to landscape mode instead of portrait mode with the channels shown side-by-side. Future firmware updates include support for USB-serial communication and PWM generation. Since XIAO ESP32 modules are also supported, it would be nice to enable remote monitoring through WiFi or Bluetooth, but it’s not on the to-do list yet.

Nicho sells the XIAO Powerbread on Tindie for $25 with a XIAO RP2040 module. There’s currently no option to purchase the baseboard only or kits with other XIAO modules based on RP2350 or ESP32.

Jean-Luc Aufranc (CNXSoft)

Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.