Abstract: A constant-current and constant-voltage driving circuit of a DC motor is used for driving a first magnetic coil and a second magnetic coil included in the DC motor. The driving circuit includes an integrated circuit chip, a first switch and a second switch. The integrated circuit chip generates currents to drive the first switch and the second switch by using the constant-current driving method. The first switch and the second switch amplify the generated currents by using the constant-voltage driving method, to drive the first magnetic coil and the second magnetic coil, respectively. Furthermore, the driving circuit can also include a control circuit to control the first magnetic coil and the second magnetic coil with pulse width modulation signals, so as to obtain the required rotation frequency of the DC motor.