Question
IO for hall sensor probability abnormal
I use stm32f103rbt6 for bldc motor control.I config three gpio as pulldown for hall sensor, in addition,these IOs with external 3k resistors pull to 5V.But sometimes the motor halls readback by mcu are all low level.However, in fact, motor hall is good.The problem is resolved while I configs these three gpio as pullup,and then config them as pulldown.
I don't know why.Somebody can explain the reason to me?These problem appeared three times over last year, for about 1500 products.