| 摘要 |
A driving device for a three-phase brushless motor offers stable rotation characteristics even in case of polarity inversion resulting from braking applied, noise appearing, or other factors arising during rotation of the motor. The driving device has a comparator circuit for comparing the back electromotive forces appearing in the motor individually with the common-terminal voltage to output square-wave signals, a synthesizing circuit for producing drive signals, a circuit for producing from the square-wave signals a speed signal and then shifting the phase thereof to produce a phase signal, and a current supply circuit for supplying drive currents to the motor in accordance with the drive signals and the phase signal. The driving device further has a selector circuit for feeding a select signal back to the gate circuits provided in the stage subsequent to the comparator to perform masking. <IMAGE> |
