Disclosed herein is a device including a differential amplification unit for supplying current to the touch panel; a signal amplification unit for amplifying the output voltage of the differential amplification unit; an analog-digital conversion unit for converting the analog output signal of the signal amplification unit into a digital signal; a control unit for measuring the signal output from the analog-digital conversion unit and detecting the position of an object when the object touches the touch panel; and a sine wave generating unit for providing a sine wave signal to the differential amplification unit in response to the output signal of the control unit, supplying a maximum current to the differential amplification unit while the touch panel is in a standby state, and controlling the level of the sine wave signal in response to conductivity of the object when the object touches the touch panel.