Patent ID: 8743081

Claim:
A control device, applied in a touch panel, wherein the touch panel comprises a plurality of first direction sensing lines and a plurality of second direction sensing lines, and the first direction sensing lines and the second direction sensing lines are arranged in a staggered manner, the control device comprising: a clock generation circuit, configured to generate a first clock signal and a third clock signal according to a reference clock signal, wherein a frequency of the first clock signal associates with a frequency of the reference clock signal, a frequency of the third clock signal equals half the frequency of the reference clock signal, and a phase of the third clock signal is ahead of a phase of the first clock signal; a selection module, configured to select sensing lines to be measured from the first direction sensing lines or the second direction sensing lines according to a predetermined scanning sequence, and also configured to output a first voltage and a second voltage according to the first clock signal; a drive signal generation circuit, configured to generate a drive signal according to the reference clock signal, wherein the drive signal is applied to sensing lines other than the sensing lines to be measured, the drive signal has a first drive voltage level and a second drive voltage level, and a frequency of the drive signal is half the frequency of the reference clock signal; a digital to analog conversion module, configured to selectively generate a third voltage or a fourth voltage according to a comparison signal, the first clock signal and the third clock signal; a first capacitor, coupled between the selection module and a differential detection circuit, and configured to manifest a variation of the third voltage on the first voltage; a second capacitor, coupled between the selection module and a differential detection circuit, and configured to manifest a variation of the fourth voltage on the second voltage; and the differential detection circuit, configured to detect the first and second voltages to generate the comparison signal; wherein the predetermined scanning sequence comprises a first scan and a second scan following the first scan; the selection module selects a first sensing line and a second sensing line, and connects the two selected sensing lines to the first and the second capacitors during the first scan; the selection module selects a third sensing line and a fourth sensing line, and connects the two selected sensing lines to the first and second capacitors during the second scan; and either (a) the first, second, third, and fourth sensing lines are arranged in sequence, or (b) the first and third sensing lines are arranged alternately, the second and fourth sensing lines are arranged alternately, and the second sensing line is adjacent to the first sensing line.