Patent · US Expired

Low noise amplifier/mixer/frequency synthesizer circuit for an RF system

US5574405A · kind A · utility

20Cited by
8References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 22, 1995
Grant dateNov 12, 1996
Priority date
Expiry dateAug 22, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B1/26
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A low noise amplifier (LNA)/mixer/frequency synthesizer circuit for the front end of a RF system. The LNA/mixer/frequency synthesizer circuit is fabricated as an integrated circuit utilizing 0.6 .mu.M CMOS technologies. The LNA within the circuit is provided a bias current from a power supply. Due to the CMOS construction of the LNA, a significant amount of unused power is available within the LNA. The frequency synthesizer requires the same bias current as does the LNA. The frequency synthesizer is directly coupled to the LNA, wherein the unused bias current of the LNA is used to supply the required bias current to the oscillators within the frequency synthesizer. Since the bias current used by the frequency synthesizer is drawn from the surplus of the LNA, a RF system front end is provided that has greatly reduced power requirements. The LNA is coupled to the frequency synthesizer, via an inductor. The inductor provides resonance to a node between the LNA and the frequency synthesizer that joins to the mixer. The inductor suppresses band harmonics while preserving the unused bias current.

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