This puzled me because the 4 circuits on PWM12 was copied from the working motor controller, but looking at the schematics I suddenly realized that 3.3V out from the buck converter is connected to ground – which explains why I draw 10mA++ extra current and why the internal logic don’t respond – it was shorted. I actually have the same bug on the motor controller as well, but I have obviously fixed it there and forgotten to take a note – bummer!
I looked at various schematics using DRV8313 to make it simple and must have picked up this bug. I don’t use 3.3V from DRV8313 because it is to little, so all I needed to do wss to cut 3.3V loose from ground and things should work as expected. The 3.3V on DRV8313 actually annoy me – it is only 10mA – unusable for most things.
As I said – something utterly simple and stupid, staring me in the face and duplicated on all 4 circuits – doh.