Patent ID: 9134857
Filing Date: 2015-09-15
Classification: G06F

Abstract:
1. An adaptive digital filtering method for touch data acquired in a touch display device including a plurality of sense channels in a touch system, the method comprising: storing the touch data in a buffer; prestoring signal-to-noise ratio (SNR) and coordinate jitter values according to digital filter order in a memory; estimating a SNR for the stored touch data; selecting a digital filter tap for a digital filter having a plurality of filter taps by comparing the prestored SNR with the estimated SNR and comparing the prestored coordinate jitter values with a preset standard jitter specified for the touch system; filtering the touch data using the digital filter after selecting the digital filter tap; after estimating of the SNR, determining a noise level reference value based on the estimated SNR; and performing noise nulling on stored touch data having a value less than the noise level reference value, wherein the noise level reference value is determined such that the estimated SNR satisfies a condition for the preset standard jitter, and wherein the selecting a digital filter tap for a digital filter having a plurality of filter taps comprises selecting a smaller number of digital filter taps as the estimated SNR increases.