@inproceedings{da2b1f415bf243999b8da95fd4a032ce,
title = "Application of code division multiple access technology in readout circuit and system design for an ultra-thin on-cell flexible capacitive touch panel",
abstract = "A capacitive sensing circuit including electrodes for a 7-inch ultra-thin flexible on-cell touch panel has been designed. Implementing code-division multiple sensing (CDMS) with Walsh transform to scan Tx electrodes is chosen to improve the signal-to-noise ratio (SNR). The algorithm applies to field programmable logic array (FPGA). The sensing readout algorithm is applied to work on 4 Tx transmitter electrodes and 4 Rx sensing electrodes. The switched-capacitor (SC) circuit is applied to avoid disturbing sample signal from parasitic capacitance and enlarge the voltage difference from capacitance changes of the touch panel. 12-bit ADC to transfer the front-end analog signal to digital code. The digital part adopts a correction algorithm to eliminate the background value of the panel, the moving average algorithm has an adjustable signal-to-noise ratio function, and the Walsh conversion demodulation algorithm improves the touch report rate to achieve high SNR with up-to 34 dB.",
keywords = "CDMA, Finite element simulation, Multi-channel drive, On-cell capacitive touch panel, Readout circuit",
author = "Lin, {Ying Jia} and Su, {Ying Cheng} and Chao, {Paul C.-P.} and Zhang, {Jia Yu} and Pribadi, {Eka Fitrah}",
note = "Publisher Copyright: {\textcopyright} 2019 ASME.; ASME 2019 28th Conference on Information Storage and Processing Systems, ISPS 2019 ; Conference date: 27-06-2019 Through 28-06-2019",
year = "2019",
month = jun,
day = "27",
doi = "10.1115/ISPS2019-7522",
language = "English",
series = "ASME 2019 28th Conference on Information Storage and Processing Systems, ISPS 2019",
publisher = "American Society of Mechanical Engineers (ASME)",
booktitle = "ASME 2019 28th Conference on Information Storage and Processing Systems, ISPS 2019",
address = "美國",
}