SCX Digital Car PCB

The task is to design a compact PCB that drops straight into an SCX 1/32 car so it can run on a digital track. I want the board to read the track’s reed-sensor signal, let me assign any of 20 unique car IDs in firmware, and expose a surface-mount USB-C port on the edge for easy flashing once the body shell is back on.

Size must stay close to the original analogue board footprint (about 24 × 18 mm, height under 6 mm) but I can adapt mounting holes or connector positions if you have a cleaner layout idea. Power comes from the standard track pickups (nominal 14–18 V DC), so include an efficient buck or LDO to feed the microcontroller and reed circuitry. I haven’t locked the MCU yet; pick anything small, inexpensive, and easy to program—ATmega, STM32, ESP32, or similar—so long as it supports a simple bootloader I can reach over USB-C.

Deliverables
• Schematic
• PCB layout and Gerbers (KiCad or Altium)
• Drill files, pick-and-place, and full BOM with distributor part numbers
• Minimal firmware that recognises reed input, stores/changes up to 20 IDs, and shows how to reflash through the USB-C port
• Brief build and programming guide

Acceptance criteria: design passes DRC; USB-C enumerates and lets me update firmware; ID selection works for all 20 addresses; reed input triggers reliably in bench tests.

Feel free to ask for any chassis measurements or photos you need while routing.