Patent ID: 8907905

Claim:
A sensing device for determining N touch signals, wherein N is a positive integer, and the sensing device comprising: a selector for selecting an ith touch signal and an (i+1)th touch signal from the touch signals according to at least one selection control signal, i is a positive integer from 1 to (N−1); a sensing module connecting to the selector in series and comprising: a first differential amplifier for comparing the selected touch signals and producing a first differential signal according to a plurality of first control signals; a first sensing line comprising a first switch and a first charge maintenance circuit for receiving the ith touch signal and transmitting the ith touch signal to a first end of the first differential amplifier, wherein the first charge maintenance circuit connects to the first switch in series and receives the ith touch signal when the first switch is closed according to the control of a first part of the first control signals; and a second sensing line comprising a second switch and a second charge maintenance circuit for receiving the (i+1)th touch signal and transmitting the (i+1)th touch signal to a second end of the first differential amplifier, wherein the second charge maintenance circuit connects to the second switch in series and receives the (i+1)th touch signal when the second switch is closed according to the control of the first part of the first control signals; and a detection module connecting to the sensing module in series for according to a plurality of second control signals, generating an averaged sensing value and a reference value from the first differential signal and comparing the averaged sensing value with the reference value to produce a second differential signal.