| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a driver for piezoelectric actuator which can suppress drop in charge current at the final stage of charge. <P>SOLUTION: A driver IC47 includes a constant current source 50 on the charge side; a constant current source 51 on the discharge side; a plurality of charge switches SW1, which switch the connection/break between the constant current source 50 on the charge side and a plurality of active parts 41a; a plurality of discharge switches SW2 which switch the connection/break between the constant current source 51 on the discharge side and the plurality of active parts 41a; and a charge/discharge control circuit 52, which decides the changeover timing of the charge switch SW1 and the discharge switch SW2 and controls the charging time and the discharging time of the active parts 41a. Furthermore, the charge/discharge control circuit 52 controls the charge time so that the quantity of charge charged in each active part 41a becomes less than the maximum quantity of charge that the active parts 41a is able to accumulate. <P>COPYRIGHT: (C)2011,JPO&INPIT |
