Patent · US Expired

2-stage large bandwidth amplifier using diodes in the parallel feedback structure

US6861908B2 · kind B2 · utility

2Cited by
3References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 24, 2003
Grant dateMar 1, 2005
Priority date
Expiry dateAug 21, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F3/3432
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

There is disclosed an improved 2-stage large bandwidth amplifier (20) comprised of two stages formed by first and second bipolar transistors (Q1,Q2) configured in common emitter that are connected in series with their emitters connected to a first supply voltage (Gnd). The input signal (Vin) is applied to the base of said first transistor via an input terminal (11), while the output signal (Vout) is available at an output terminal (12) connected to the collector of said second transistor. A parallel feedback structure (13′) is provided. It consists, in a first branch, of two diodes (D1,D2) in series connected between a second supply voltage (Vcc) and the collector of the second bipolar transistor, and in another branch of a third bipolar transistor (Q3) configured in emitter follower with a resistor (Rf) in the emitter. The base and the collector of said third bipolar transistor are respectively connected to the common node of said diodes and to said second supply voltage. The resistor is connected to the common node of said first and second transistors to inject the feedback signal (Vf). Because, the two bodies have a low internal resistance and reduce the collector capacitance of…

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