My customer is producing DRV10987 for an year, but recently they have issue regarding initial motor stopping at the open to closed loop transition.
And I found below blog post for open loop and it mentioned "start lose sync and stall". I think this is my customer issue.
But the thing is they are using for year without this issue.
"During an open loop, the motor is driving without any information about the position of the rotor. This phase of open-loop commutation, also known as blind commutation, is very important because it is directly related to system reliability. If blind commutation is not configured correctly, the motor will start, lose sync and stall."
My question is what could make this issue? like board noise, missed or not enough time of BEMF calculation?
Issue rate is 23units /100ku.
(belows are evaluated for testing)
SPEED PWM duty is 33% as a starting point. --> Once decrease it like 11% it work well .
customer VCC is 26.3V which is little bit higher. --> If decrease VCC with external P/S like 24 or 23V then it work well.
Rated speed is 200Hz and Op2ClsThr = 25.6Hz. --> If increase Op2ClsThr like 51.2Hz then it work well.
Unfortunately, it is not seen any of fault flag. device is restarted after 5 sec.