AnsweredAssumed Answered

MC33HB2001 and PWM driving

Question asked by Corentin Bazille on Jun 24, 2019
Latest reply on Jun 28, 2019 by Corentin Bazille

Hello !


I have been trying to drive a 12V, 0.8A BDC motor using an nRF52832 or STM32F042K6 to drive a MC33HB2001 using PWM.


I did understand that IN1/IN2 could be grossly compared to DIR/PWM on other drivers ; unfortunately, at the frequency at which I want to drive the motor (25kHz), I have not been able to obtain satisfying results. I have been setting IN1 at either HIGH or LOW logic level to set rotation direction, and applying 25kHz-PWM on IN2 to drive the motor.


This configuration produces very weird results : under 40% duty cycle, I cannot manage to get the motor to rotate. Above, the speed does not seem to be affected by the PWM duty cycle. In addition, the motor is submitted to high thermal stress as it heats up to over 50°C.


I'm guessing I'm doing something wrong. I have thought of leaving IN1 and IN2 in HIGH states to drive the motor, then applying a PWM wave on the Disable pin (DIS) to turn output on and off. Otherwise I have no idea how to "properly" drive the HB2001 with PWM.


Can anyone help ?


Thanks in advance !


Best regards,