PHASE-SHIFT DETECTION DEVICE, MOTOR DRIVE DEVICE, BRUSHLESS MOTOR, AND PHASE-SHIFT DETECTION METHOD

摘要

A phase-shift detection circuit detects a phase shift in motor driving, using pulse-shaped position detection signal Rd and measurement signal Ms. The position detection signal is based on sensor signal Hs from a position sensor disposed in a motor. The measurement signal is based on the induced voltage from windings. The phase-shift detection circuit includes a level difference calculator and a phase-shift calculator. The level difference calculator calculates a level difference between the level of measurement signal Ms at a rising timing of position detection signal Rd and the level of measurement signal Ms at a falling timing thereof. The phase-shift calculator calculates the amount of phase shifts based on the level difference.