Energization timing determination circuit and determination method for energization timing of motor

Abstract

An energization timing determination circuit corrects a shift contained in a position signal outputted from a position detecting means and supplies energization timing appropriate to drive a motor. A correction amount computation unit computes detection intervals obtained based on position signals outputted from filters, comparators, and a position detection unit during one cycle of electrical angle. The correction amount computation unit thereby determines the duty shift length α and phase shift length β of the position signals. A control circuit corrects energization timing based on the position signals according to the detected shift lengths.