Patent ID: 8508499

Claim:
A touch sensing circuit, comprising: a plurality of signal generators outputting a pulse signal according to a control signal; a plurality of touch detection circuits arranged as an array, generating a sensing signal according to a touch event and the pulse signal, wherein the touch detection circuits on the same row are coupled to the same signal generator; a plurality of sensing circuits respectively coupled to the touch detection circuits on the same column, generating an output signal according to the sensing signal; and a controller receiving the output signal, outputting the control signal to enable one of the signal generators outputting the pulse signal, and detecting the touch detection circuit corresponding to the touch event according to the output control signal and the output signal; wherein the signal generator comprises: a pulse width modulator outputting a pulse width modulation signal; a direct-current power source providing a direct-current voltage; a first diode coupled between the touch detection circuit and the direct-current voltage, having a first anode and a first cathode; a second diode having a second cathode coupled to the first anode, and a second anode coupled to the first cathode; and a switching circuit coupled to the pulse width modulator and the direct-current power source, switching according to the pulse width modulation signal to output the pulse signal at a connection point of the first diode and the second diode.