Custom Computer Mouse with STM32
Development of a custom computer mouse – from schematic and PCB design to a hand-soldered, functional board.
For this project I designed a computer mouse from scratch. Instead of using a ready‑made development board, I conceived and implemented the entire electronics as a custom PCB.
The schematic and PCB layout were created in EasyEDA. The core of the mouse is a STM32 microcontroller, which works with the optical PMW3360DM-T2QU sensor. Additionally, there is a USB‑C port, left and right mouse buttons, a clickable scroll wheel, a DPI button, and two LEDs directly on the board.
Since the mouse is powered over USB with 5 V, I also integrated two separate voltage regulators. These provide the required 3.3 V for the STM32 and 1.8 V for the sensor.
Several iterations were necessary before achieving a working version. I had to repeatedly review the circuit, component selection, and PCB layout, find errors, and revise individual parts. This process was a crucial part of the project, as it taught me not only the final design but also systematic troubleshooting on my own hardware.
After the final PCB was ready, I had the board fabricated at JLCPCB. I then performed the assembly myself, soldering all components by hand onto the board.
The hardware is only part of the overall project: In a separate software project I also developed the embedded software for the mouse, which processes the sensor, buttons, and scroll wheel via the STM32 microcontroller and communicates the mouse with the computer.