Patent ID: 8654089

Claim:
A touch sensing circuit, applied to a capacitance touch panel, for detecting a position of the capacitance touch panel touched by a pointing object the capacitance touch panel comprising (M*N) touch points, M first touch pad sets aligned along a first direction, and N second touch pad sets aligned along a second direction, each first touch pad set comprising at least one first touch pad, each second touch pad set comprising at least one second touch pad, the first touch pads and the second touch pads being distributed at the (M*N) touch points respectively, M and N are positive integers respectively, the touch sensing circuit comprising: a first signal input module, for inputting a first signal to the M first touch pad sets orderly along the first direction; a second signal input module, for inputting a second signal to the N second touch pad sets orderly along the second direction; a first sensing module, for sensing a first equivalent capacitance of the M first touch pad sets; a second sensing module, for sensing a second equivalent capacitance of the N second touch pad sets; and a processing unit, coupled to the first sensing module and the second sensing module, for determining the position of the capacitance touch panel touched by the pointing object according to the first equivalent capacitance and the second equivalent capacitance; wherein the first equivalent capacitance and the second equivalent capacitance are changed according to the position, the first signal, and the second signal, and the first signal and the second signal are inputted synchronously, and a first pulse width of the first signal is N times to a second pulse width of the second signal, so that the second signal input module inputs the second signal to the N second touch pad sets orderly within the pulse width of the first signal, the processing unit obtains (M*N) total equivalent capacitances corresponding to the (M*N) touch points according to the first equivalent capacitance and the second equivalent capacitance and the processing unit determines the position of the capacitance touch panel touched by the pointing object according to the (M*N) total equivalent capacitances.