Patent ID: 6998801

Claim:
A motor drive device comprising: an output stage comprising an upside power MOSFET, a downside power MOSFET and a spindle output predriver unit, said output stage driving a multiphase DC motor; a current detector for detecting a current made to flow through the multiphase DC motor; a current controller which outputs a PWM signal desired in such a manner that a current instruction signal and the current detected by the current detector coincide with each other; a PWM signal generator which generates a regenerative signal obtained by giving, to the PWM signal, dead times for avoiding simultaneous turning on of the upside power MOSFET and the downside power MOSFET for applying voltages of respective phases to the multiphase DC motor; a phase detection unit for detecting each rotational phase of the multiphase DC motor; an energizing timing controller which generates an energizing timing signal from a detection result of the phase detection unit; an output control & PWM modulation unit which generates signals for controlling on/off of the upside power MOSFET and the downside power MOSFET from the energizing timing signal and an output signal of the PWM signal generator; and a switching characteristic adjustment unit which measures a time at which the output stage is being transitioned and performs such feedback control that the time and a switching time designated coincide with each other.