Conductive touch pad with capacitive blocking filter
US5499026A · kind A · utility
49Cited by
4References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1994 |
| Grant date | Mar 12, 1996 |
| Priority date | — |
| Expiry date | Sep 30, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/9645
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A touch sensitive pad consists of a number of electrical conductive pads (10) surrounded by a conductive pad (11). Each pad (10) is connected via a respective capacitive blocking filter to a multiplexer (13) and an oscillator (14). When the touch pad is touched directly to effectively bridge between one of the pads (10) and the surrounding pad (11), a change in effective impedance is detected by a resultant variation in the frequency of the oscillator (14).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.