Radiation-sensitive switching circuits
US3944860A · kind A · utility
1Cited by
4References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 3, 1974 |
| Grant date | Mar 16, 1976 |
| Priority date | — |
| Expiry date | Jul 3, 1994 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/7955
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A radiation-sensitive switching circuit includes a light emitting diode which from time to time illuminates a photo-transistor, the photo-transistor serving when its output reaches a predetermined value to operate a trigger circuit. In order to allow for aging of the components, the current flow through the diode is increased when the output from the transistor falls below a known level. Conveniently, this is achieved by having a transistor in parallel with the diode, and turning the transistor off when the output from the photo-transistor becomes too low.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.