Patent ID: 8531139
Filing Date: 2013-09-10
Classification: H02P

Abstract:
1. A drive control circuit of a linear vibration motor, having a stator and a vibrator at least one of which is constituted by an electromagnet, which vibrates the vibrator relative to the stator by supplying a drive current to a coil of the electromagnet, the drive control circuit comprising: a drive signal generating unit configured to generate a drive signal used to alternately deliver a positive current and a negative current to the coil; an H-bridge circuit configured to generate a drive current according to the drive signal generated by said drive signal generating unit so as to supply the drive current to the coil; and a differential amplifier circuit configured to detect an induced voltage occurring in the coil wherein said differential amplifier circuit includes an operational amplifier in which an P-channel type transistor is used as a transistor that receives an input voltage, said H-bridge circuit including: wherein before said H-bridge circuit is controlled to a high impedance state, said drive signal generating unit turns on the first P-channel type transistor and the second P-channel type transistor, turns off the first N-channel type transistor and the second N-channel type transistor, and delivers a regenerative current through the coil, the first P-channel type transistor, the second P-channel type transistor and the power supply potential.