LINEAR MOTOR DRIVER AND STAGE UNIT

摘要

PROBLEM TO BE SOLVED: To provide a linear motor driver in which dynamic brake is actuated appropriately at the time of power interruption even when an excitation switching system is employed, and a stage unit comprising the driver. SOLUTION: The linear motor driver employing an excitation switching system comprises switching circuits SW1-SW4 for switching excitation of respective coils L1-L4, and a semiconductor relay switch 202 for short-circuiting a circuit including the coils L1-L4 in order to actuate the dynamic brake upon occurrence of power interruption. The switching circuits SW1-SW4 do not operate as power supply is interrupted and switching is turned off. Power supply for the switching circuits SW1-SW4 is thereby provided with a charge/discharge circuit comprising electric double layer capacitors C1-C3 so that the power supply is backed up during effective period of dynamic brake even if power supply to the switching circuits SW1-SW4 is interrupted.