DC BRUSHLESS MOTOR DRIVER WITH MOTOR LOCK PROTECTION

摘要

PURPOSE: To obtain a DC brushless motor driver with a motor lock protection in which damage of a driving element is prevented and which is automatically reset after a lock is released even when the motor is locked. ;CONSTITUTION: When a DC brushless motor 2 is locked, an oscillator 50 is operated by a signal of an FG output of a logic arithmetic unit 30 to forcibly switch NchFETs 31, 33, 35 through AND gates 40a-40c and high-side output buffers 37a-37c to control a lock current, and to obtain a boosted voltage sufficient to drive the NchFETs 31, 33, 35 provided at a high-side of the motor 2. After the lock is released, the oscillator 50 is automatically stopped oscillation by a signal of the FG output of the unit 30, and reset. Thus, power loss and damage of the NchFETs can be prevented.;COPYRIGHT: (C)1993,JPO&Japio