Patent ID: 8841875
Filing Date: 2014-09-23
Classification: G04C,H02P

Abstract:
1. An electronic watch, comprising: a stepper motor including a rotor and a coil; a motor driver for driving the stepper motor; a reference signal generation circuit for outputting various kinds of timing signals; a pulse shaping circuit for generating various kinds of pulse signals for driving the stepper motor, in response to the various kinds of timing signals output from the reference signal generation circuit; a pulse selection circuit for selecting various kinds of pulses supplied from the pulse shaping circuit and outputting the selected pulses to the motor driver; and a rotation detection circuit for detecting whether the rotor has rotated or not based on counter-electromotive force resulting from free oscillation of the rotor, the pulse shaping circuit comprising: wherein the electronic watch further comprises a detection pulse change factor detector configured to detect a factor of changing a pulse width of the detection pulse, and output a detection signal, wherein the detection pulse generation circuit is capable of changing the pulse width of the detection pulse, and wherein the detection pulse generation circuit changes the pulse width of the detection pulse to be output, in accordance with the detection signal of the detection pulse change factor detector.