Driver circuit apparatus for driving a three-phase motor with a single magneto-sensitive device

An integrated circuit for driving a three-phase motor in response to a single signal of three-phase signals to be applied to stator coils of the motor, comprising:

• a first amplifier for amplifying the single signal as a first phase signal on the basis of a first inverse phase signal which is a 180.degree. phase-shifted signal relative to the single signal, to output a first amplified phase signal;
• a first phase shifter for generating a second phase signal in response to the first phase signal, the second phase signal having a phase difference of 120.degree. relative to the first phase signal.
• a second phase shifter for generating a second inverse phase signal to the first inverse phase signal, the second inverse phase signal having a phase difference of 120.degree. relative to the first inverse phase signal;
• a second amplifier for amplifying the second phase signal on the basis of the second inverse phase signal to output a second amplified phase signal which is a 120.degree. phase-shifted signal relative to the first amplified phase signal;
• an output control for producing a third phase signal in response to the first and the second amplified phase signals by means of a control logic thereof to output the three-phase signals applied to stator coils of the motor, the third phase signal having a phase difference of 120.degree. relative to each of the first and the second phase signals.

A driver circuit apparatus for generating a three-phase signal suitable for driving a three-phase motor, said apparatus comprising:

• a single magneto-sensitive element for generating a first phase signal in response to a detected rotor position of a three-phase motor;
• and
• an integrated circuit for selectively applying a current signal to the three-phase motor in response to the first phase signal generated from the single magneto-sensitive element,
• said integrated circuit comprising:
• a first phase shifter for receiving the first phase signal and generating a second phase signal having a phase difference of 120.degree. relative to the first phase signal;
• and
• an output control for producing a third phase signal in response to the first and the second phase signals input to the output control, said three-phase signal being produced by means of a control logic thereof, the third phase signal having a phase difference of 120.degree. relative to each of the first and the second phase signals.

A method for driving a three-phase motor comprising:

• detecting a rotor position of a three-phase motor using a single magneto-sensitive element;
• generating a first phase signal from the single magneto-sensitive element and a first inverse phase signal which is a 180.degree. phase-shifted signal relative to the first phase signal in response to the detected rotor position;
• amplifying the first phase signal and outputting a first amplified phase signal;
• phase shifting the first phase signal to a second phase signal having a phase difference of 120.degree. relative to the first phase signal;
• phase shifting the first inverse phase signal to a second inverse phase signal having a phase difference of 120.degree. relative to the first inverse phase signal;
• amplifying the second phase signal and outputting a second amplified phase signal;
• producing a third phase signal in response to the first and the second amplified phase signals, the third phase signal having a phase difference of 120.degree. relative to each of the first and the second phase signals;
• and
• selectively applying the first, second and third phase signals to stator coils of the three-phase motor in response to the signals generated from the single magneto-sensitive element.