I can drive my BLDC motor from my own board which has a DRV8308 using Register mode. I have recently tried to get it to work using Clock Frequency Mode but the motor does not run, it occasionally pulses but nothing more. I have used the eval kit to get the registers and settings right and the motor runs fine on this. I have read back and confirmed the registers are set the same on my board. As the CLKIN pin was not used in Register mode I wanted to make sure this was not the problem so I wired the CLKIN signal from the eval board to my board and it worked, despite the signals being the same frequency. The only difference is that the CLKIN from my board is 5V instead of 3.3V from the eval. I then wired the CLKIN from my board into the eval board expecting it not to work but it did! The obvious answer is that by setting the output frequency on my board is changing something else and preventing it from working but after probing all the pins this doesn't seem to be the case. Any suggestion?
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