So we have a four wheel robot using 25d 34:1 pololu motors w/encoders. We’re using a 7.4v lipo battery(so max voltage supply is about 8.4v) and the motor drivers are being controlled with a Xula2. For connections we have the not_PWM inputs grounded, a 18.75kHz PWM supply, and the direction pins controlled accordingly. The enable pin is always hi and the data ground is also connected. After deliberation we determined the vin on the data pin side isn’t necessary as long as motor power is connected.
Now for our issue, we have burned out one chip on two separate boards, which is the determination because there was only random supply to the motor on a previously working setup and swapping to our backup board resolved the issue. During running we have a very rapid control system that will independently change the speeds of each motor independently. We have not experienced any of the protection shut down symptoms, the driver just quits working and isn’t restored after setting for a period of time. Additionally the driver was connected to different motors so a high draw from a problem motor is unlikely.
What can cause this driver to fail so abruptly?