I have a geared DC motor rated at 24V 2A. I intend driving with PWM from a 20X2 into an L298 driver (because I have some in the box). The idea is to drive the L298 bridge inputs from the 20X2 to provide direction control and apply PWM to the L298 enable input. I can then turn on both bridge inputs for fast stop. This is a servo type application with position feedback from a 10 turn potentiometer. The motor load has a high inertia so using PWM means I can ramp down the speed before a final stop and save stripping the gears!
The only problem I have is deciding on what frequency to run the PWM. Is there a rule of thumb for PWM drive frequency. I have seen controllers that run a variety of rates from 1kHz through 100kHz. I am guessing there is a limit related to the motor characteristics.
Thanks
Richard
The only problem I have is deciding on what frequency to run the PWM. Is there a rule of thumb for PWM drive frequency. I have seen controllers that run a variety of rates from 1kHz through 100kHz. I am guessing there is a limit related to the motor characteristics.
Thanks
Richard