Patent · US Expired

Amplification circuit which includes an input-current compensation device

US5999045A · kind A · utility

4Cited by
8References
34Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 12, 1997
Grant dateDec 7, 1999
Priority date
Expiry dateNov 12, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F1/302
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An amplification circuit comprising a device for compensating for its input current. The amplification circuit includes an amplifier and a capacitor located on the input side of the amplifier. The input-current compensation device consists of a current generator, generating a current Ig, a switch and a device for measuring the average current charging or discharging the capacitor during the time that the switch is open. The current Ig is such that: Average current=Ia-Ig, where Ia is the input current of the amplifier. The value of the average current is close to zero. The value of the current Ig which the current generator must output, so as to make the average current close to zero, is calculated using the device for measuring the average current. The invention particularly applies to a circuit for restoring the DC component of a video signal.

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