Motor Controller for a Robot Arm
Worked for 3 mins 12 sec
ERC found one real schematic-library conflict: the selected VQFN buck part marks its NC pad as no-connect even though the datasheet says to tie that pad to SW. I’m switching to the HSOIC LMR33630 variant with no NC pad so the schematic can verify cleanly.
Worked for 4 mins 36 sec
Implemented and verified the schematic for the closed-loop brushed DC motor controller.
What was completed:
- Added a robust 12 V nominal motor-controller architecture: MC33926 H-bridge, STM32G431 MCU, INA240 current sense, LMR33630 3.3 V buck, LM74700 reverse protection, encoder conditioning, connectors, LEDs, and protection.
- Wired power, motor drive, current sensing, encoder A/B/Z, SWD, UART control, reset/BOOT0, and fault/status paths.
- Ran schematic/ERC checks; there are no open ERROR/WARNING/UNCERTAIN checks in the reviewed schematic categories.
Project files created/updated:
Open items:
- Layout is not started yet; high-current motor paths, shunt Kelvin routing, buck layout, and thermal copper will be critical.
- Firmware starter is a HAL bring-up baseline; final PID/current-limit tuning still needs motor characterization.
Suggested next steps:
- Set PCB constraints: board size, stackup, current-aware trace widths, and clearance rules.
- Place components with power path and thermal priorities.
- Route the PCB, then run DRC/PI checks.
- Add test points for 3V3, VM_PROT, HBRIDGE_EN, current sense, and encoder signals.
Set constraints and layout
Set PCB constraints
Place components
Route the PCB
Add test points
Review BOM risks
