A Novel Analog-Front-End Circuit of the Touch System for Display Panel

In this paper, a novel analog-front-end (AFE) circuit architecture of the mutual capacitive touch system based on cross-correlation technology is proposed for the large-size display panel. The weak touch signal submerged by display panel noise could be detected by the proposed cross-correlation AFE. Due to the use of cross-correlation technology, only the data around the touch points are collected by a low-speed analog to digital convertor (ADC) in the proposed AFE rather than collecting full-screen data in the traditional AFE. The accuracy and efficiency of AFE data acquisition are significantly improved through the proposed cross-correlation computation methodology. Simultaneously, the complex digital processing module is removed, and the system cost and computation complexity are reduced. The average single channel area and power consumption of the proposed AFE are 2 merely 0.015mm and 0.227mW, respectively.