Patent ID: 8432111

Claim:
A driving device in a direct current (DC) brushless motor system comprising: a pulse amplitude modulation (PAM) circuit including an input end is connected to a pulse width modulation (PWM) and outputting a PAM signal; a detective circuit including a first comparator and a second comparator, and a first input end of the first comparator is connected to a first voltage circuit and a second input end is connected to a first level voltage and outputs a first signal, and a first input of the second comparator is connected to a second voltage circuit and a second input is connected to a second level voltage and outputs a second signal, wherein an input end of the first voltage circuit is connected to the PAM control signal and an input end of the second voltage circuit is connected to the first signal; a driving circuit, and one input end of the driving circuit is connected to the PAM circuit, another input end is connected to the second signal of the detective circuit and an output end is connected to the external motor; and a digital phase control circuit, and one input end of the digital phase control circuit is connected to the PAM circuit, another input end is connected to the first signal of the detective circuit and an output end is connected to the driving circuit.