Hi.. new here.. I’m using raspberry pi pico to drive 2 stepper motors with drv8825… everything works on breadboard.. but when both motors move fast at same time, pico resets randomly… i tried adding extra caps and slower ramp, still sometimes happen.. maybe power supply droop??
Also.. thinking to design PCB… how to route high current stepper traces without making noise on logic lines.. where to put decoupling caps?? should i add separate ground for motors?? thanks in advance…
Pico resets are likely caused by power dips when both motors draw high current. Use a separate 12 V supply for the DRV8825 motors …… keep logic and motor power separate …… common grounds of both supplies …. sometimes it gives headaches
For pcb ….. short traces for motor power and keep them away from Pico logic/data lines ….. my recommendation is to use a seperate power and gnd planes, best practice ….. read this guide to understand planes: Power and Ground Plane Design Considerations in PCB Layout - PCB Design & Layout - PCBway
Place 0.1 uF capacitor close to the Pico VCC pins, and optionally a larger 10–47 uF near the motor drivers to smooth spikes ….
Dilshana has a good point about power, make sure you have a big enough power supply for both your uC and motor.
It could also be RF noise generated by the combination of motor and driver. Some ferrite beads on the motor and power wiring might help if you have any available.
Also, check the datasheet for your driver IC. Is should have a recommended PCB layout. See if your layout differs drastically to the recommended.