Title :
A 70dB SNR capacitive touch screen panel readout IC using capacitor-less trans-impedance amplifier and coded Orthogonal Frequency-Division Multiple Sensing scheme
Author :
Seunghoon Ko ; Hyungcheol Shin ; Hongjae Jang ; Ilhyun Yun ; Kwyro Lee
Author_Institution :
KAIST, Daejeon, South Korea
Abstract :
A high SNR capacitive touch screen panel (TSP) readout IC is designed. In this paper, Orthogonal Frequency Division Multiple Sensing method is proposed to enhance frame scan rate. Capacitor-less Trans-Impedance Amplifier and Direct Digital Frequency Synthesizer based on Harmonic Rejection Ratio DAC is proposed to save chip area. The prototype IC with 0.18um CMOS achieves 70dB SNR for a finger and 400Hz frame scan rate.
Keywords :
CMOS integrated circuits; OFDM modulation; digital-analogue conversion; direct digital synthesis; operational amplifiers; readout electronics; touch sensitive screens; CMOS technology; TSP; capacitive touch screen panel readout integrated circuits; capacitorless transimpedance amplifier; coded orthogonal frequency-division multiple sensing scheme; direct digital frequency synthesizer; harmonic rejection ratio DAC; size 0.18 mum; Demodulation; Electrodes; Multiaccess communication; OFDM; Sensors; Signal to noise ratio;
Conference_Titel :
VLSI Circuits (VLSIC), 2013 Symposium on
Conference_Location :
Kyoto
Print_ISBN :
978-1-4673-5531-5
