A motor drive circuit comprising: a drive circuit configured to supply a drive current to a drive coil of a motor; a control circuit configured to control an operation of the drive circuit; a locking protection circuit configured to control an operation of the control circuit so that the drive circuit stops supplying the drive current to the drive coil, if a rotation signal, indicating rotation of the motor, is not generated during a predetermined time period although the drive circuit is supplying the drive current to the drive coil; and a prohibition circuit configured to prohibit the locking protection circuit from controlling the control circuit.