DC Motor Control Pulse Width Modulation (PWM) eTPU Functions

The PWMMDC, PWMF, and PWMC functions enable the eTPU to generate PWM signals for driving a motor. The PWM Master (PWMMDC) function synchronizes and updates up to three PWM phases. The phases may be driven either by the PWM Full Range (PWMF) function that enables a full 0% to 100% duty-cycle range, or by the PWM Commutated (PWMC) function that enables switching the phase ON and OFF.

The PWMF and PWMC functions generate the PWM signals. The PWMMDC function controls the PWMF and PWMC functions, does not generate any drive signal, and can be executed even on an eTPU channel not connected to an output pin. If connected to an output pin, the PWMMDC function turns the pin high and low, so that the high-time identifies the period of time in which the PWMMDC execution is active. In this way, the PWMMDC function, as with many of the motor-control eTPU functions, supports checking eTPU latencies using an oscilloscope.

Functionality of PWMMDC + PWMC.

 

Functionality of PWMMDC + PWMF.

For full description refer to AN2840.