The DRV8308 register setup I am using is shown below.
The mode is 120 deg commutatioin with single Hall (BASIC = 0, ENSINE=0)
This runs the motor perfectly over a wide speed range. LOCKn active after startup at any speed.
The problem comes when doing nothing more than setting ENSINE=1. The motor draws large current, the phase current is erratic. Continuously goes in/out of LOCK. Setting before start or setting on-the-fly does same. Setting MOD120=3970, does the same.
ENSINE should just change the PWM flat duty to sinusoidal duty. It should not change commutation angle (my assumption about what is happening). The switch between 180 comm single Hall and 120 comm single Hall should be seamless. I don't understand what is happening here.
A good overall block diagram of the system, filter topology, startup algorithm, would be very helpful.
I am unable to get Sine mode to operate in my drive nor in the evaluation kit.