Hi, I'm developing a FOC board based on STM32G431RBT6 and I wanted to test the board in open loop before attempting to FOC.
While testing for current sensing, I'm getting a lot of noise which messes up the measurement.
I tried disconnecting the motor to be sure that the source of the noise is not the SMPS on the board, there is little to no noise on the ADCs without the motor.
It looks like this when running the motor in open loop with very low RPM. With increased RPM, the noise becomes more prominent since the motor is not under any load and drawing less current at the same power, and it becomes impossible even to see the shape of the sine wave.
And there's that weird spikes at the bottom of the sine which I don't have any clue about.
I'm using internal opamps with PGA set to 16 in as differential low side current sensing amps. ADC is triggered at every overflow event through OC4REF.
What's the possible causes for this problem and how to solve?
