Patent · US Expired

Amplifier with input drift voltage compensation

US4628274A · kind A · utility

19Cited by
3References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 30, 1985
Grant dateDec 9, 1986
Priority date
Expiry dateApr 30, 2005

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F3/45977
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

The invention concerns an amplifier comprising means for compensating for the input drift voltage. During a preparation phase, the input signal of the amplifier (10) is nullified by short-circuiting the inputs (12) and (13) by means of the change-over switch (30) and the output (15) is connected to a capacitor (40) and to a secondary input (14) of the amplifier. The secondary input has a substantially lower gain than the gain relative to the main input (13), which makes it possible substantially to reduce the effect of charge injection caused by opening of the switch (60). In the amplification phase, the input (13) receives an input signal (V1) and the input drift voltage (.alpha.V) is compensated by means of the value stored in the capacitor (40).

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