Patent ID: 8736578

Claim:
A sensing method for a capacitive touch panel including a first trace, a second trace, and a lateral capacitor formed at an intersection of the first trace and the second trace, the sensing method comprising: (a) in a first clock phase, applying a first voltage to the first trace and the second trace and setting a voltage across a sensing capacitor, wherein during the first clock phase, the first trace is always set to the first voltage; and (b) in a second clock phase, switching the first trace being connected from the first voltage to a second voltage and connecting the second trace to a first terminal of the sensing capacitor to thereby cause a voltage variation at a second terminal of the sensing capacitor; wherein the second terminal of the sensing capacitor is connected to a first input terminal of an operational amplifier and the first terminal of the sensing capacitor is connected to a second input terminal of the operational amplifier during the first clock phase; and wherein the first terminal of the sensing capacitor is connected to both the second input terminal of the operational amplifier and the second trace, and the second terminal of the sensing capacitor is connected to an output terminal of the operational amplifier during the second clock phase.