BLDC MOTOR DRIVING CIRCUIT OF CONTROLLING A DC OFFSET OF A HOLE DEVICE AND A BLDC MOTOR HAVING THE SAME

摘要

PURPOSE: A BLDC motor driving circuit of controlling a DC offset of a hall device is provided to control the constant speed of a motor precisely by removing an offset with the constraint of an output signal of a hall device. CONSTITUTION: A hall device(61) outputs first and second signals having phases opposite to each other. A first low pass filter(62) inputs the first signal of the hall device(61) and passes low frequencies. A second low pass filter(63) inputs the second signal of the hall device(61) and passes low frequencies. An operational amplifier(64) is provided. The non-inverting terminal of the operation amplifier(64) is connected to the output terminal of the first low pass filter(62). The inverting terminal of the operation amplifier(64) is connected to the input and output terminals of the second low pass filter(63).