Patent ID: 7322065

Claim:
A washing machine, comprising: a disinfecting liquid dispenser supplying a disinfecting liquid to disinfect laundry; a drive unit outputting first and second voltages to determine a concentration of the disinfecting liquid; and a control unit detecting the concentration of the disinfecting liquid and controlling the drive unit so that the disinfecting liquid has a concentration within a preset range, wherein the drive unit receives first and second switching signals having opposite phases from the control unit, the drive unit comprising: a first switching unit turned on in response to the pulse width modulation signal and outputting the first control voltage proportional to a duty ratio of the pulse width modulation signal when the first switching signal is at a preset voltage level, and a second switching unit turned on in response to the pulse width modulation signal and outputting the second control voltage proportional to the duty ratio of the pulse width modulation signal when the second switching signal is at the preset voltage level.