| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an inexpensive circuit configuration which prevents the generation of a through current between transistors when a single-phase brushless DC motor is operated by full-wave drive through an H-bridge circuit, thus drives the motor at high efficiency. <P>SOLUTION: To create a current-passing signal that does not generate a through current in the H-bridge circuit, a differential amplifying circuit and a reverse circuit each using an operational amplifier are used to set a bias voltage to a proper Hall element and a gate interrupting voltage to a MOSFET. An LPF is added to the differential amplifying circuit to change the gradient of a rising voltage waveform and a falling voltage waveform to drive the motor with a preset current-passing angle. The motor is thus driven efficiently in an inexpensive circuit configuration. <P>COPYRIGHT: (C)2009,JPO&INPIT |
