Patent · US Active

Wideband active balun LNA topology with narrow-band filtering and noise cancelling

US9054648B1 · kind B1 · utility

38Cited by
1References
7Claims
0Family size

Assignees

Inventor

  • Jun Xu · Longbeilingcun, CN

Key dates

Filing dateDec 10, 2013
Grant dateJun 9, 2015
Priority date
Expiry dateDec 10, 2033

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F2203/45704
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

The present invention provides a wideband active balun LNA topology with narrow-band filtering and noise cancelling. The amplifier includes three transconductance stages, a feedback network, and a load. The first and second transconductance stages are connected in parallel to receive the input signal. The differential output of the first transconductance stage is fed back to voltage input through a differential-to-single-end-end feedback network, while the output of the first transconductance, passing through the third transconductance, is added to the output of the second transconductance stage in proper phase. The present invention accomplish both wideband low-noise amplification and narrow-band filtering without inserting interface stages, thereby improving the linearity and noise performance of the whole circuit. Noise cancellation technique is implemented in differential way to ensure the low noise figure. The present invention also achieves single-end to differential conversion with balanced output and superior second order linearity performance.

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