Patent · US Expired

AGC circuit

US6242981A · kind A · utility

5Cited by
4References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 16, 1999
Grant dateJun 5, 2001
Priority date
Expiry dateNov 16, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03G3/3052
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

To make variable time constant of an AGC loop of an AGC circuit, there is provided an AGC circuit including a control circuit for controlling a level of an input signal and outputting an output signal, a rectifying circuit for rectifying the output signal from the control circuit and outputting a voltage V DET having a level in correspondence with a level of the output signal and a voltage to current converting circuit for converting the output voltage V DET from the rectifying circuit into a current. The voltage to current converting circuit is constituted to provide a differential amplifier supplied with the output voltage V DET from the rectifying circuit. A current I DET outputted by the differential amplifier is converted into AGC voltage V AGC by being supplied to a capacitor. By the AGC voltage V AGC, AGC is carried out by controlling the level of the input signal at the control circuit. By changing a magnitude of an operating current I CONT of the differential amplifier, an alternating current amplification factor of the differential amplifier is changed to thereby change the time constant of AGC.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.