Patent attributes
Provided is a drive circuit for a two-coil stepper motor, including: a rotor; a stator including first, second, and third stator magnetic-pole portions; a coil A to be magnetically coupled to the first stator magnetic-pole portion and the third stator magnetic-pole portion; a coil B to be magnetically coupled to the second stator magnetic-pole portion and the third stator magnetic-pole portion; a drive pulse generation circuit configured to output a drive pulse; a detection pulse generation circuit configured to output a detection pulse for detecting counter-electromotive currents generated in the coil A and the coil B; and a rotation detection circuit configured to receive a detection signal generated due to the detection pulse as input to determine whether or not the rotor has rotated.