SLLSFP7A december 2022 – april 2023 MCT8315A
PRODUCTION DATA
Align is enabled by configuring MTR_STARTUP to 00b. The MCT8315A aligns the motor by injecting a DC current using a particular phase pattern (phase-C high-side FET and phase-B low-side FET are ON) - current flowing into phase-B and flowing out from phase-C for a certain time configured by ALIGN_TIME.
The duty cycle during align is defined by ALIGN_DUTY. In MCT8315A, current limit during align is configured by ALIGN_CURR_THR.
A fast change in the phase current during align may result in a sudden change in the driving torque and this could result in acoustic noise. To avoid this, the MCT8315A ramps up duty cycle from 0 to until it reaches ALIGN_DUTY at a configurable rate set by ALIGN_RAMP_RATE. At the end of align routine, the motor will be aligned at the known position.