Optoelectronic relay circuit having charging path formed by a switching transistor and a rectifying diode
US5057694A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 1990 |
| Grant date | Oct 15, 1991 |
| Priority date | — |
| Expiry date | Mar 6, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S136/293
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A semiconductor relay circuit includes an output FET connected to a diode array. The diode array generates a photovoltaic output in response to a light signal from a light emitting element. Across the drain and gate of the FET is a series circuit of a semiconductor device and a rectifier is connected, the switching transistor is being made conductive upon receipt at the diode array of the light signal and forms a charge current path for an accumulated charge across the gate and source of the FET. The rectifier restrains a photocurrent from reversely flowing between the drain and gate of the FET. Turning-on and turning-off operations of the relay circuit can be thereby made both achievable at a higher speed, and the reverse flow of the photocurrent upon the conduction of the output FET can be prevented from occurring.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.