Patent · US Expired

Touch actuated electronic switch

US3947696A · kind A · utility

4Cited by
1References
82Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 4, 1974
Grant dateMar 30, 1976
Priority date
Expiry dateNov 4, 1994

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S200/02
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A touch actuated electronic switch is disclosed including a surface, accessible to the touch of a human, interconnected with a differential amplifier. In the preferred embodiment, if increased noise immunity or noise protection is desired, a twisted pair of wires is used and interconnected at one end with one wire electrically connected to the touch surface and the other substantially equal length wire being unconnected. Both wires, at the other end, are connected to the input to the differential amplifier. A common mode alternating voltage signal is then provided to the differential amplifier and a substantial alternating frequency output signal shunt is applied to the differential amplifier, in the preferred embodiment, across terminals conventionally used for D.C. offset null purposes. The output of the differential amplifier is then interconnected to an integrator, in the preferred embodiment a capacitor, and the integrator is in turn connected to an additional amplifier. The output terminals of the additional amplifier, in the preferred embodiment, act as an electrical switch with the electrical impedance across the output terminals in a first state assuming a high impedance, …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.