| 摘要 |
PURPOSE:To simplify a circuit and reduce ununiformity of working extremely by using two switching elements, and by determining the direction of current flowing through a voice coil. CONSTITUTION:A voice coil motor(VCM) drive circuit is composed of a current determining resistor 22 connected to the one end of a voice coil 21 for driving a VCM, and analog switches 23 and 24 connected to the other end and applying supply voltage VCC and supply voltage VDD selectively to the voice coil 21. To a space between the current determining resistor 22 and the voice coil 21, control voltage V for controlling the current rate of the voice coil 21 is applied, and to the other end of the current determining resistor 22, supply voltage VR is applied, and VCC>VR>VDD is set. Accordingly, when the analog switches 23 and 24 are respectively turned ON, then current flows through the voice coil 21 in the inverse direction, and so the direction of the VCM can be controlled. |
