DRIVING CIRCUIT OF VIBRATION WAVE MOTOR

摘要

PROBLEM TO BE SOLVED: To provide the driving circuit of a vibration wave motor which can make an A/D converter with a built-in microcomputer exhibit same performance both in the case of 8 bits and in the case of 16 bits. SOLUTION: A digital unit of which the driving circuit of a vibration wave motor is composed is divided into upper and lower hierarchy 8-bit D/A converters 1b and 1d. The revolution command value of a revolution command means 1 which 16-bit resolution is divided and inputted to the respective 8-bit D/A converters 1b and 1d. The analog DC voltage outputs of the respective 8-bit D/A converters are inputted to a ladder resistance network 2 composed of four resistors. As a result, the output voltage of the ladder resistance network is obtained as an analog DC voltage with 16-bit resolution by which the revolution of the vibration wave motor is controlled.