Patent ID: 7706111
Filing Date: 2010-04-27
Classification: H02H

Abstract:
1. A motor lock detection circuit for detecting lock of a motor, comprising: a binarizing circuit configured to binarize a signal, obtained from the motor, having a frequency corresponding to rotation speed of the motor, to generate a binary signal; an edge detecting circuit configured to generate an edge detection signal when detecting an edge of the binary signal; a first counter configured to count based on a first counter clock, be reset according to the edge detection signal generated by the edge detecting circuit, and generate a count signal when counting for a first count period longer than an interval between edges of the binary signal; and a second counter configured to count based on a second counter clock, be reset according to the count signal, and generate a motor lock detection signal indicative of detection of lock of the motor when counting for a second count period longer than the first count period.