| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor drive circuit that is easy in satisfying conditions of both a driving characteristic and the stability of a feedback control circuit. SOLUTION: The motor drive circuit comprises a chopper-type DC-DC converter circuit that includes a switching element, a diode, an inductance element, a PWM control circuit, and a first capacitor connected between an output end and the ground; a bridge-type switching circuit that drives the coil of a motor by using desired magnetism based on the output voltage of the DC-DC converter circuit; a resistor for current detection that is connected between the switching circuit and the ground; and a second capacitor that is connected between the output end of the DC-DC converter circuit and a terminal of the resistor that is not grounded. By properly selecting values of the first capacitor and the second capacitor, the conditions of both the constant current driving characteristic and the stability of the feedback control circuit can be satisfied. COPYRIGHT: (C)2005,JPO&NCIPI |
