Variable gain amplifier
US6163215A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 22, 1999 |
| Grant date | Dec 19, 2000 |
| Priority date | — |
| Expiry date | Apr 22, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G1/0023
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In a variable gain amplifier controlling a gain by using differential amplifiers with a gain control signal, a gain switchover differential amplifier or a bias circuit which composes a current mirror with the gain switchover differential amplifier is connected between a high and a low gain differential amplifier for the same bias current which are mutually connected to share load resistances for the same output polarity and a bias current source common to both of the differential amplifiers, to perform switchover operations of the high and the low differential amplifier by a gain control signal, and a current source which flows a fixed offset current through at least the low one of the high and the low differential amplifier is provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.