Optical gain control of GaAs microwave monolithic integrated circuit distributed amplifier
US4859965A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1989 |
| Grant date | Aug 22, 1989 |
| Priority date | — |
| Expiry date | Feb 27, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B2210/006
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An optical gain control circuit for controlling the gain of a GaAs MMIC dributed amplifier having a dc gain control is provided. Variable intensity light from a controlled LED is directed to the surface of a GaAs multi-finger FET by means of an optical fiber. The FET is gate biased to a point near pinch-off to maximize its light sensitivity and the drain and source of the FET are serially connected with a fixed resistance in a dc voltage divider circuit so that the output of the voltage divider circuit changes as a function of the change in light intensity of the LED. A MMIC operational amplifier connected in an inverter mode is coupled between the output of the voltage divider circuit and the dc gain control of the distributed amplifier to control the gain of that amplifier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.