Touch actuated electronic switch including protection from high potential electricity
US3992634A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 9, 1975 |
| Grant date | Nov 16, 1976 |
| Priority date | — |
| Expiry date | May 9, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/962
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A touch actuated electronic switch is disclosed including at least one surface, accessible to the touch of a human, interconnected with an active circuit and protected against static electricity. In the preferred embodiment, the active circuit is differential sensing circuitry, preferably, dual input logic circuitry, and most requiring protection from static electricity at this time, a MOS exclusive OR gate. In the preferred embodiment where the interconnection between the logic circuit and the surfaces is desired to include long wires, a twisted pair of wires is used if increased noise immunity or noise protection is desired. The twisted pair is interconnected at one end with one wire electrically connected to the touch surface and the other substantially equal length wire being unconnected or connected to a second touch surface. Both wires are connected at their other ends to the dual inputs to the logic circuitry. Also connected to the dual inputs are dual impedances which, when taken together with the impedance of the body of the human operator, provide protection against static or other high potential electricity. A common mode alternating voltage signal is then provided throu…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.