Abstract

Touch-based interactivity has become an important function in displays. This paper reports on the signal processing of touch signals in which touch interactivity is processed as an image, and correlated double sampling (CDS) algorithm is applied for both common-mode noise reduction and global multivalued offset cancellation. Based on experimental results, we achieved a boost in SNR of 7.6 dB. The processed signal reduces detection errors and power consumption of the system.

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  28. J. Bussat, S. P. Hotelling, Redundant Sensing Element Sampling U.S. Patent US20 140 015 774 A1 (2014).
  29. J. B. Roberts, Baselining Technologies in Force-based Touch Panel Systems U.S. Patent US20 030 210 235 A1 (2003).
  30. C. J. Brown, H. Kato, K. Maeda, B. Hadwen, "A continuous-gain silicon-system LCD with optical input function," IEEE J. Solid-State Circuits 42, 2904-2912 (2007).
  31. I. Yang, O. Kwon, "A touch controller using differential sensing method for on-cell capacitive touch screen panel systems," IEEE Trans. Consum. Electron. 57, 1027-1032 (2011).
  32. O. Kyong, H. Lim, "Photo sensing circuits using low-temperature polycrystalline silicon TFTs and photo diode for smart functional displays," SID Symp. Dig. Tech. Papers (2010) pp. 684-687.
  33. J. Lee, "A 10-touch capacitive-touch sensor circuit with the time-domain input-noise isolation," SID Symp. Dig. Tech. Papers (2012) pp. 493-496.
  34. 3M Co.“Touch technology brief: Projected capacitive technology,” (2011).
  35. J. Yang, "A highly noise-immune touch controller using Filtered–Delta-Integration and a charge-interpolation technique for 10.1-inch capacitive touch-screen panels," IEEE ISSCC Dig. Tech. Papers (2013) pp. 390-391.
  36. H. Jang, H. Shin, S. Ko, I. Yun, K. Lee, "2D coded-aperture-based ultra-compact capacitive touch-screen controller with 40 reconfigurable channels," IEEE ISSCC Dig. Tech. Papers (2014) pp. 218-219.
  37. S. Ko, "Low noise capacitive sensor for multi-touch mobile handset’s applications," Proc. IEEE ASSCC (2010) pp. 1-4.
  38. S. Ko, H. Shin, H. Jang, L. Yun, K. Lee, "A 70 dB SNR capacitive touch screen panel readout IC using capacitor-less trans-impedance amplifier and coded Orthogonal Frequency-Division Multiple Sensing scheme," Proc. IEEE Symp. VLSIC (2013) pp. C216-C217.
  39. J. E. Park, D. H. Lin, D. K. Jeong, "A reconfigurable 40-to-67 dB, 50-to-6400 Hz frame-rate, column-parallel readout IC for capacitive touch-screen panels," IEEE J. Solid-State Circuits 49, 2305-2318 (2014).
  40. K. Kim, "A capacitive touch controller robust to display noise for ultrathin touch screen displays," Proc. IEEE ISSCC, Medical, Displays and Imagers (2012) pp. 116-117.
  41. T. Marks, II“Touchscreen latencies in flagship tablets,” (2013) http://appglimpse.com/blog/touchmarks-ii-touchscreen-latencies-in-agship-tablets/.
  42. C. Luo, M. A. Bokar, A. J. Redfern, J. H. McClellan, "Compressive sensing for sparse touch detection on capacitive touch screens," IEEE Trans. Emerg. Sel. Topics Circuits Syst. 2, 639-648 (2012).
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2014 (3)

J. Lee, M. T. Cole, J. C. S. Lai, A. Nathan, "An analysis of electrode patterns in capacitive touch screen panels," J. Display Technol. 10, 362-366 (2014).

Y. Ahn, T. Ahn, K. Lee, J. Kang, "Avoiding noise frequency interference with binary phase pulse driving and CDS for capacitive TSP controller," IEICE Electron.Exp. 11, 1-7 (2014).

J. E. Park, D. H. Lin, D. K. Jeong, "A reconfigurable 40-to-67 dB, 50-to-6400 Hz frame-rate, column-parallel readout IC for capacitive touch-screen panels," IEEE J. Solid-State Circuits 49, 2305-2318 (2014).

2012 (2)

C. Luo, M. A. Bokar, A. J. Redfern, J. H. McClellan, "Compressive sensing for sparse touch detection on capacitive touch screens," IEEE Trans. Emerg. Sel. Topics Circuits Syst. 2, 639-648 (2012).

D. Lim, S. Lee, W. Choi, J. Park, D. Jeong, "A digital readout IC with digital offset canceller for capacitive sensors," J. Semicond. Tech. Sci. 12, 278-285 (2012).

2011 (1)

I. Yang, O. Kwon, "A touch controller using differential sensing method for on-cell capacitive touch screen panel systems," IEEE Trans. Consum. Electron. 57, 1027-1032 (2011).

2010 (1)

G. Barrett, R. Omote, "Projected-capacitive touch technology," Inf. Display Mag. 26–3, 16-21 (2010).

2007 (1)

C. J. Brown, H. Kato, K. Maeda, B. Hadwen, "A continuous-gain silicon-system LCD with optical input function," IEEE J. Solid-State Circuits 42, 2904-2912 (2007).

1996 (1)

C. Enz, G. Temes, "Circuit techniques for reducing the effects of op-amp imperfections: Autozeroing, correlated double sampling, and chopper stabilization," Proc. IEEE 84, 1584-1614 (1996).

1974 (1)

M. H. White, D. R. Lampe, "Characterization of surface channel CCD image arrays at low light levels," IEEE J. Solid-State Circuits sc–9, 1-13 (1974).

IEEE J. Solid-State Circuits (2)

C. J. Brown, H. Kato, K. Maeda, B. Hadwen, "A continuous-gain silicon-system LCD with optical input function," IEEE J. Solid-State Circuits 42, 2904-2912 (2007).

M. H. White, D. R. Lampe, "Characterization of surface channel CCD image arrays at low light levels," IEEE J. Solid-State Circuits sc–9, 1-13 (1974).

IEEE J. Solid-State Circuits (1)

J. E. Park, D. H. Lin, D. K. Jeong, "A reconfigurable 40-to-67 dB, 50-to-6400 Hz frame-rate, column-parallel readout IC for capacitive touch-screen panels," IEEE J. Solid-State Circuits 49, 2305-2318 (2014).

IEEE Trans. Consum. Electron. (1)

I. Yang, O. Kwon, "A touch controller using differential sensing method for on-cell capacitive touch screen panel systems," IEEE Trans. Consum. Electron. 57, 1027-1032 (2011).

IEEE Trans. Emerg. Sel. Topics Circuits Syst. (1)

C. Luo, M. A. Bokar, A. J. Redfern, J. H. McClellan, "Compressive sensing for sparse touch detection on capacitive touch screens," IEEE Trans. Emerg. Sel. Topics Circuits Syst. 2, 639-648 (2012).

IEICE Electron.Exp. (1)

Y. Ahn, T. Ahn, K. Lee, J. Kang, "Avoiding noise frequency interference with binary phase pulse driving and CDS for capacitive TSP controller," IEICE Electron.Exp. 11, 1-7 (2014).

Inf. Display Mag. (1)

G. Barrett, R. Omote, "Projected-capacitive touch technology," Inf. Display Mag. 26–3, 16-21 (2010).

J. Display Technol. (1)

J. Semicond. Tech. Sci. (1)

D. Lim, S. Lee, W. Choi, J. Park, D. Jeong, "A digital readout IC with digital offset canceller for capacitive sensors," J. Semicond. Tech. Sci. 12, 278-285 (2012).

Proc. IEEE (1)

C. Enz, G. Temes, "Circuit techniques for reducing the effects of op-amp imperfections: Autozeroing, correlated double sampling, and chopper stabilization," Proc. IEEE 84, 1584-1614 (1996).

Other (33)

J. Ohta, Smart CMOS Image Sensors and Applications (CRC, 2007).

NPD Display Search company"Quarterly touch panel market analysis," (2014) http://www.displaysearch.com/cps/rde/xchg/displaysearch/hs.xs/touch_panel_market_analysis.asp.

C. William, H. S. George, Discriminating Contact Sensor U.S. Patent 3 911 215 A (1975).

V. Souchkov, Capacitive touchscreen signal acquisition without panel reset U.S. Patent US8 274 491 B2 (2012).

K. Kim, "A capacitive touch controller robust to display noise for ultrathin touch screen displays," Proc. IEEE ISSCC, Medical, Displays and Imagers (2012) pp. 116-117.

T. Marks, II“Touchscreen latencies in flagship tablets,” (2013) http://appglimpse.com/blog/touchmarks-ii-touchscreen-latencies-in-agship-tablets/.

O. Kyong, H. Lim, "Photo sensing circuits using low-temperature polycrystalline silicon TFTs and photo diode for smart functional displays," SID Symp. Dig. Tech. Papers (2010) pp. 684-687.

J. Lee, "A 10-touch capacitive-touch sensor circuit with the time-domain input-noise isolation," SID Symp. Dig. Tech. Papers (2012) pp. 493-496.

3M Co.“Touch technology brief: Projected capacitive technology,” (2011).

J. Yang, "A highly noise-immune touch controller using Filtered–Delta-Integration and a charge-interpolation technique for 10.1-inch capacitive touch-screen panels," IEEE ISSCC Dig. Tech. Papers (2013) pp. 390-391.

H. Jang, H. Shin, S. Ko, I. Yun, K. Lee, "2D coded-aperture-based ultra-compact capacitive touch-screen controller with 40 reconfigurable channels," IEEE ISSCC Dig. Tech. Papers (2014) pp. 218-219.

S. Ko, "Low noise capacitive sensor for multi-touch mobile handset’s applications," Proc. IEEE ASSCC (2010) pp. 1-4.

S. Ko, H. Shin, H. Jang, L. Yun, K. Lee, "A 70 dB SNR capacitive touch screen panel readout IC using capacitor-less trans-impedance amplifier and coded Orthogonal Frequency-Division Multiple Sensing scheme," Proc. IEEE Symp. VLSIC (2013) pp. C216-C217.

J. Park, D. Lim, D. Jeong, "A 6.3 mW high-SNR frame-rate scalable touch screen panel readout IC with column-parallel $\Sigma-\Delta$ ADC structure for mobile devices," Proc. IEEE A-SSCC (2013) pp. 357-360.

R. J. Lowles, J. A. Robinson, K. Wu, System and Method of Integrating a Touchscreen Within an LCD U.S. Patent US7 388 571 B2 (2008).

J. H. Yang, "A novel readout IC with high noise immunity for charge-based touch screen panels," Proc. IEEE CICC (2010) pp. 1-4.

A. Middleton, B. Rella, H. J. Kim, M. Baily, A. Coleman, G. Garavuso, “FTIR multi-touch screen technology,” Rochester Inst. Technol. Project P12302 (2012).

S. Aras, T. Nihei, A. Rahman, Touch Sensing Method and Apparatus U.S. Patent 20 130 015 867 A1 (2011).

O. Nys, H. Ballan, N. Chappatte, F. Vuadens, Circuit for capacitive touch applications U.S. Patent US20110001492 A1 (2011).

H. Ballan, N. Chappatte, O. Nys, F. Vuadens, Circuit for capacitive touch applications W.O. Patent WO20 120 34 714 A1 (2012).

Y. Guedon, K. B. Tan, K. A. Ningrat, D. Guo, Capacitive Sensing Analog Front End U.S. Patent US20 110 242 048 A1 (2011).

Cypress Semiconductor Corp“Using correlated double sampling to reduce offset, drift and low frequency noise,” http://www.cypress.com/?rID=2894.

O. Korobeynikov, J. M. Kulinets, V. Protasov, P. R. Nuykens, Methods and Apparatus for Reducing Non-ideal Effects in Correlated Double Sampling Compensated Circuits U.S. Patent US20 090 273 392 A1 (2009).

J. Bussat, S. P. Hotelling, Redundant Sensing Element Sampling U.S. Patent US20 140 015 774 A1 (2014).

J. B. Roberts, Baselining Technologies in Force-based Touch Panel Systems U.S. Patent US20 030 210 235 A1 (2003).

A. Nathan, J. C. S. Lai, S. Cha, C. Church, Pressure Sensing Display Device U.S. Patent US20 140 008 203 A1 (2014).

H. Shin, S. Ko, H. Jang, I. Yun, K. Lee, "A 55 dB SNR with 240 Hz frame scan rate mutual capacitor $30 \times 24$ touch-screen panel read-out IC using code-division multiple sensing technique," IEEE ISSCC Dig. Tech. Papers (2013) pp. 388-389.

N. Miura, "A 1 mm-pitch $80 \times 80$ -channel 322 Hz-frame-rate touch sensor with two-step dual-mode capacitance scan," Proc. ISSCC, MEMs, and Displays (2014) pp. 216-217.

Y. Kim, T. H. Ahmed, "Low energy and latency touch detection using group testing," Proc. EUSIPCO (2013) pp. 1-5.

S. Hotelling, J. Strickon, B. Huppi, Multipoint touchscreen U.S. Patent US20 060 097 991 A1 (2006).

Z. Baharav, R. Kakarala, "Capacitive touch sensing: Signal and image algorithms," Proc. SPIE Conf. Comput. Imaging (2011).

M. G. A. Mohamed, "Efficient algorithm for accurate touch detection of large touch screen panels," Proc. IEEE ISCE (2014) pp. 1-2.

ARM“Cortex-A5 processor performance,” http://www.arm.com/products/processors/cortex-a/cortex-a5.php.

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