Hello,
I am currently testing a board made with the MCT8316Z (hardware variant) using a motor with a 4A max draw with a 12.1V VM. The failure that I experienced was a short from VM to GND internal to the driver IC. My team and I confirmed that the short is in the driver IC by isolating the ICs nets and removing the capacitors between VM and GND, and still saw continuity through the driver.
A previous version of the board I am testing had overheating issues which have been confirmed to be fixed in this version (I have have ran the motor at full speed for ~2hrs with no issue). The problem that I need help diagnosing is that one of the boards that I was testing failed after < 10 seconds of running the motor. So far this has only happened with 1 out of the 5 boards that I have had available for testing, with 25 more boards becoming available over the next week.
The most likely explanation for the failure that my colleges and I have been able to come up with is that a connection from the motor coils to the driver may have came loose during testing. I was being rushed to test the boards and the motor was not properly secured to the test bench and would have created vibrations. The board was secured to a non-conductive test surface and powered through a DC power supply (capable of supplying 8A at VM).
I was wondering what the possible failure modes would be if a motor was disconnected while running, or any other common failure modes that you might see with this driver.
Thank you for the help!
