Phase adjustment circuit, motor driving control circuit, and motor apparatus

Abstract

A motor apparatus is constructed to compensate for a delay in operation of the motor apparatus, so that the efficiency is improved and noise is reduced over a broad motor rpm range by driving the motor at the optimum timing. The motor driving control circuit of the motor apparatus includes a phase adjustment circuit which inputs signals of the U phase, V phase and W phase output by rotational position signal amplifiers, and performs an adjustment for the respective signals so that the phases are arbitrarily advanced by a ratio corresponding to phase adjustment voltages, an automatic gain control circuit which inputs the output signals of this circuit and the gain of which is feedback-controlled according to the driving currents of the armature coils of the motor, an FG circuit which produces a periodic pulse train from the rotational position signals, and a frequency-voltage conversion circuit which performs a conversion to a voltage corresponding to the frequency of the pulse train, and outputs the converted voltage as a phase adjustment voltage.