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A study on Detecting a Ghost-key using Additional Coating at the Membrane type Keyboard)
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 Title & Authors
A study on Detecting a Ghost-key using Additional Coating at the Membrane type Keyboard)
Lee, HyunChang; Lee, MyungSeok;
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This paper presents a novel method for detecting a ghost key at the membrane type keyboard, which has additional resistive coating to the membrane film. Also, the optimal ratio of resistances for detecting a ghost key was designed based on the characteristics of the membrane film. The optimal ratio of resistances was considered to be able to detect the worst case (i.e., difference voltage between normal key and ghost key is minimum). The ability of the proposed methods are evaluated by simulation studies in this paper. In order to verify the proposed method, the experiment was carried out with a designed circuit and A/D (analog to digital) in MCU (micro controller unit). The proposed method is implemented into the membrane type keyboard and is verified by experimental results.
phantom key;ghost key;membrane;keyboard;dynamic scanning;
 Cited by
坂卷 佳壽美(Sakamaki Kazumi), 實戰的 マイコン 應用技術, pp. 123-127, CQ 出版, 1982.

Frank Vahid and Tony Givargis, Embedded System Design - A Unified Hardware/Software Introduction, pp. 97-98, John Wiley &Sons, 2002.

Don Johns, "Membrane Versus Mechanical Keyboards," Electronic products Vol.38 No.1, pp. 43, 1995.

Steven F. Barrett and Daniel J. Pack, Embedded Systems - Design and Applications, pp. 313-319, Pearson Prentice-Hall, 2005.

Ronald J. Tocci and Lester P. Laskowski, Microprocessors and Microcomputers Hardware and Software, pp. 271-279, Prentice-Hall, 1982.

Lan McLoughlin, Computer Peripherals, Chap.4, pp. 1-17, Nanyang Technological University, 2001.

SungKook Han, Microcomputer - Understanding and Application Design, pp. 85-92, Jip-Moon-Dang, 1984.

Matthew Ahn, "Study of Inputting System of Matthew Ahn's Keyboard," Korean Language Information Science, Vol.11, No.2, pp.40-46, Dec. 2009.

Shun-Pin Lin, "Input device with Ghost key suppression," US Patent US8754790B2, Jun. 2014.

Liu Wen-Tong and Chang Chien-Hui, "Method and system for detecting hidden ghost keys on keyboard matrix," US Patent US8749407B2, Oct. 2014.

Chun-Hung Cheng and Ying-Wen Bai, "Anti-Ghost Key Design for a Notebook Keyboard," Canadian Conference on Electrical and Computer Engineering, Proceeding of the IEEE 28th, pp.577-580, May. 2015.

Paul H. Dietz and Jonathan Westhues, "Resistive Switch Matrix," US Patent Application Publication US20100066572A1, Mar. 2010.