Patent ID: 6713983
Filing Date: 2004-03-30
Classification: H02P

Abstract:
A pre-driver circuit connectable with both a motor driver for driving a motor and a digital processor for servo-controlling a plurality of motors by performing a programmed calculation and inputting/outputting signals through an interface pin, said pre-driver circuit comprising:a speed detection signal receiver adapted for receiving a speed detection signal representing a rotational speed of said motor, from a rotational speed detector; an amplifying unit adapted for amplifying said speed detection signal received by said speed detection signal receiver; a sender connectable with one of pins of said digital processor, adapted for sending the speed detection signal amplified by said amplifying unit, to the digital processor; a first receiver connectable with one of a plurality of pins of said digital processor, adapted for receiving a start signal for starting to drive said motor; a second receiver connectable with one of a plurality of pins of said digital processor, adapted for receiving a pulse width modulated signal generated by the digital processor based on said speed detection signal sent by said sender for servo-controlling the rotational speed of said motor; a position detection signal receiver adapted for receiving a position detection signal representing a rotational position of said motor, from a position detector; and a control signal generator adapted for generating a control signal to control driving signals supplied to each phase of said motor, in accordance with said pulse width modulated signal received by said second receiver and said position detection signal received by said position detection signal receiver when the start signal received by said first receiver is active, and supplying the generated signal to said motor driver.