SLLSFU1A December 2023 – July 2024 MCF8315C
PRODMIX
If the motor is spinning forward (same direction as the commanded direction) with sufficient speed (BEMF), the MCF8315C resynchronizes with the spinning motor and continues commutation by going directly to closed loop operation. If the motor speed is too low for closed loop operation, MCF8315C enters open loop operation to accelerate the motor till it reaches sufficient speed to enter closed loop operation. By resynchronizing to the spinning motor, the user achieves the fastest possible start-up time for this initial condition. This resynchronization feature can be enabled or disabled through RESYNC_EN. If resynchronization is disabled, the MCF8315C can be configured to wait for the motor to coast to a stop and/or apply a brake. After the motor has stopped spinning, the motor start-up sequence proceeds as in Case 1, considering the motor is stationary.