POWER FOLDING MIRROR AND OPERATING CIRCUITS FOR THE SAME

摘要

PURPOSE: A power folding mirror and a driver circuit thereof are provided to protect a motor by turning off a switching device with a second transistor, which drops a bias voltage to a turn-off level, when detected voltage is over a cut-off voltage. CONSTITUTION: A switching device(40) is turned on/off by bias voltage. A motor(50) is turned on by turning on the switching device. A current detector(60) outputs detection voltage by detecting current flowing in the motor. A fold-back unit(70) includes a first transistor(T1,T2) and a second transistor(T3,T4). The first transistor includes a first control receiving the detection voltage. The second transistor includes a second control terminal connected to a first terminal of the first transistor. If the detection voltage is over the cut-off voltage, the second transistor turns off the switching device by dropping the bias voltage to a turn-off level.