摘要 |
Disclosed herein is an apparatus for driving a touch panel, which calibrates a drift of an output voltage, generated by a change of an external environment or touch panel, thereby having excellent noise characteristics, high touch sensitivity. The apparatus includes a touch panel having a plurality of pixels. Each of the pixels is connected to a first capacitor in which their electric charges are stored. A differential amplifier receives and amplifies the amount of electric charges generated by a change in the capacitance of the first capacitor of the touch panel, inputted through two input terminals and outputs the amplified voltage to two output terminals. An analog to digital converter (ADC) receives an output of the differential amplifier as an input and converts the output into a digital value. A reference voltage calibrator outputs positive and negative voltages to the differential amplifier and calibrates a reference voltage. An error calibrator outputs positive and negative voltages to the differential amplifier and calibrates two outputs of the differential amplifier within a voltage input range of the ADC. A controller feeds back the two outputs of the differential amplifier, which are beyond the voltage input range of the ADC, to the error calibrator.
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