A Nonlinear Electrical Resonator as a Simple Touch-Sensitive Switch with Memory

Lars Q. English, Mauro David Lifschitz, Sunil Acharya

a.t.Q Services LLC, Carlisle, USA.
Department of Physics and Astronomy, Dickinson College, Carlisle, USA.

DOI: 10.4236/cs.2013.41001                

Abstract

We introduce a novel switching mechanism that relies on the bistability of a simple nonlinear electrical resonator which incorporates a varactor diode as its capacitive element. The switching action can be made fast and is self-contained in that no further circuitry is necessary. Unlike a flip-flop, whose state is flipped by applying a TTL pulse, this nonlinear switch can be engaged external to the circuit via magnetic, inductive or capacitive coupling; in this way, the switch becomes intrinsically touch-sensitive. Alternatively, the switching action can also be accomplished using frequency-shift-keying (FSK) modulation, which holds the promise of fast manipulation of the memory state. We demonstrate the potential application of these ideas by constructing a touch-sensitive LED lattice.

Keywords

Nonlinear Switch; Electrical Resonator; Bistability; Touch Sensitivity

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	M. Yamada and K. Watanabe, “A Capacitive Pressure Sensor Interface Using Oversampling Delta-Sigma Demodulation Techniques,” IEEE Transactions on Instrumentation and Measurement, Vol. 46, No. 1, 1997, pp. 3-7. doi:10.1109/19.552148
[2]	M. Lee, “The Art of Capacitive Sensing,” EE Times (An UBM Electronics Publication), Planet Analog Supplement, 2006.
[3]	J. Schoning, et al., “Multi-Touch Surfaces: A Technical Guide,” Technical Report TUM-I0833, 2008.
[4]	H. M. Gibbs, “Optical Bistability: Controlling Light with Light,” Academic Press, New York, 1985.
[5]	H. Wang, D. Goorskey and M. Xiao, “Controlling Light by Light with Three-Level Atoms Inside an Optical Cavity,” Optics Letters, Vol. 27, No. 15, 2002, pp. 1354-1356. doi:10.1364/OL.27.001354
[6]	D. Gourier, E. Aubay and J. Guglielmi, “Bistable Switching of Nuclear Polarization States in Gallium Oxide,” Physical Review B, Vol. 50, No. 5, 1994, pp. 2941-2952. doi:10.1103/PhysRevB.50.2941
[7]	H. B. Chan and C. Stambaugh, “Fluctuation-Enhanced Frequency Mixing in a Nonlinear Micromechanical Oscillator,” Physical Review B, Vol. 73, No. 22, 2006, Article ID: 224301. doi:10.1103/PhysRevB.73.224301
[8]	J. Casals-Terre, A. Fargas-Marques and A. M. Shkel, “Snap-Action Bistable Micromechanisms Actuated by Nonlinear Resonance,” Journal of Microelectromechanical Systems, Vol. 17, No. 5, 2008, pp. 1082-1093. doi:10.1109/JMEMS.2008.2003054
[9]	F. Palmero, L. Q. English, J. Cuevas, R. Carretero-Gonzalez and P. G. Kevrekidis, “Discrete Breathers in a Nonlinear Electric Line: Modeling, Computation, and Experiment,” Physical Review E, Vol. 84, No. 2, 2011, Article ID: 026605. doi:10.1103/PhysRevE.84.026605
[10]	J. Han and M. A. Shannon, “Smooth Contact Capacitive Pressure Sensors in Touch-and Peeling-Mode Operation,” IEEE Sensors Journal, Vol. 9, No. 3, 2009, pp.199-206. doi:10.1109/JSEN.2008.2011090