Other Parts Discussed in Thread: DRV8308
Hi,
I am using the DRV8307 to spin a BLDC Motor that has a filter wheel attached to it.
In my software I watch for the LOCKn Signal to be set before performing any other functions.
The issue I am seeing is that after I see the LOCKn signal go active, I have to continue to monitor the Motor RPMs before it actually stabilizes and then I can continue on.
The data sheet does not really give any information on the LOCKn signal.
I read a locked thread that says the LOCKn signal of the DRV8307 effectively has a 12.5% speed threshold (SPEEDTH) and requires 4 Hall_U periods to lock. The HALL_U frequency must be faster than 2Hz for lock to occur.
I am driving the DRV8307 with a 25kHz PWM signal and adjusting the duty cycle to control the speed. Is there a way to adjust SPEEDTH on the DRV8307 or do I have to switch to the more configurable DRV8308?
Thanks,
Reif Heck