×

Variable gain amplifier

  • US 5,477,191 A
  • Filed: 06/30/1994
  • Issued: 12/19/1995
  • Est. Priority Date: 06/30/1993
  • Status: Expired due to Fees
First Claim
Patent Images

1. A variable gain amplifier comprising first and second gain stages cascade connected between first and second terminals of a voltage supply generator, characterized in that the first gain stage comprises a differential stage coupled to the first terminal of the voltage supply generator and having first and second input terminals which form first and second input terminals for the amplifier, as well as first and second output terminals coupled to the second terminal of the voltage supply generator, respectively through first and second variable resistance load elements having a first common control terminal, and that the second gain stage comprises first and second transistors each having first and second terminals and a control terminal, the control terminals of said first and second transistors being respectively connected to the first and second output terminals of the differential stage, the first terminals of said first and second transistors being both coupled to the first terminal of the voltage supply generator and forming respectively a first output terminal and a second output terminal for the amplifier, the second terminals of the first and second transistors being both coupled to the second terminal of the voltage supply generator through respective first and second variable resistance circuit elements which are both connected to a second common control terminal.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×