Tool/software:
Dear teams，
When using DRV8701P to drive a DC brushed motor and measuring the GH pin with an oscilloscope, an abnormal waveform was observed.
PWM control frequency 20KHZ, powered by DC24V.
The test waveform is as follows:
The schematic diagram is as follows:
Could you please help me see what the reason is?
Hi Chu,
Thank you for the post.
When using DRV8701P to drive a DC brushed motor and measuring the GH pin with an oscilloscope, an abnormal waveform was observed.
Was this waveform captured between GH1 or GH2 and GND? The VGS waveform is defined between either GH1 and SH1 or GH2 and SH2 depending on the bridge conduction direction. Could you please check and confirm the VGS waveform between GHx and SHx? You may have to use a differential probe to avoid scope GND connected to electrical safety GND. Also the probe must be high impedance to avoid discharging the gate drive. Below would be the expectation.
Please confirm the measurement GND reference. As well as what is the reason for VGS waveform check? Was it to debug any other issue - if so what was the issue? Can we also get IN1, IN2 and OUT1, OUT2 waveforms and motor current waveforms with a current probe. Thank you.
Regards, Murugavel
