標題: Design and validation of the readout circuitry for an in-cell active-matrix capacitive (IAMC) touch panel
作者: Ku, Tsung-Yen
Chao, Paul C. -P.
Tu, Tse-Yi
Huang, Chin-Hai
Liu, En-Chih
Yeh, Ming-Hua
影像與生醫光電研究所
電子工程學系及電子研究所
Institute of Imaging and Biomedical Photonics
Department of Electronics Engineering and Institute of Electronics
公開日期: 1-Nov-2018
摘要: This study is dedicated to design an in-cell active-matrix capacitive (IAMC) touch panel and its readout circuitry. This IAMC touch panel is in a structure that embeds all components for touch panel in a standard active matrix display. In this way, the thickness of the display-touch combined module can be significantly reduced, but introducing much noise from display to touch module, leading to higher mis-judgements on touches. To solve the problem, this study proposes a new readout circuit and digital signal processing techniques to tackle well the aforementioned noise for much accurate touch sensing. The readout consists essentially of an analog front-end switched capacitor charge amplifier (SCCA), a 12-bit SAR ADC and a digital signal processing (DSP) unit for calibration and filtering. A field-programmable gate array (FPGA) board is adopted to implement the designed digital signal processing in practice. The performance of the readout is tested for a 5x12, 0.88-inch IAMC touch panel with a scanning frequency of 200Hz. Experimental data show clearly that the sensed capacitance was successfully converted to 200 digits in a full dynamic range of 12-bits and a SNR of 52dB, which facilitates well accurate determination of touches and locations on an IAMC touch panel.
URI: http://dx.doi.org/10.1007/s00542-018-3948-5
http://hdl.handle.net/11536/148303
ISSN: 0946-7076
DOI: 10.1007/s00542-018-3948-5
期刊: MICROSYSTEM TECHNOLOGIES-MICRO-AND NANOSYSTEMS-INFORMATION STORAGE AND PROCESSING SYSTEMS
Volume: 24
起始頁: 4551
結束頁: 4559
Appears in Collections:Articles