The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 01, 2005
Filed:
Jul. 24, 2003
Bertrand Gabillard, Paris, FR;
Michel Rivier, Barbizon, FR;
Fabrice Voisin, La Courneuve, FR;
Philippe Girard, Corbeil Essonnes, FR;
Bertrand Gabillard, Paris, FR;
Michel Rivier, Barbizon, FR;
Fabrice Voisin, La Courneuve, FR;
Philippe Girard, Corbeil Essonnes, FR;
International Business Machines Corporation, Armonk, NY (US);
Abstract
There is disclosed an improved 2-stage large bandwidth amplifier () comprised of two stages formed by first and second bipolar transistors (Q,Q) configured in common emitter that are connected in series with their emitters connected to a first supply voltage (Gnd). The input signal (V) is applied to the base of said first transistor via an input terminal (), while the output signal (V) is available at an output terminal () connected to the collector of said second transistor. A parallel feedback structure (') is provided. It consists, in a first branch, of two diodes (D,D) 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 (Q) 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 (V). Because, the two bodies have a low internal resistance and reduce the collector capacitance of the second transistor, the overall bandwidth of the improved amplifier is significantly extended in the very high frequencies (e.g. 20 GHz and above).