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:
May. 27, 1980
Filed:
Dec. 04, 1978
Tom L Blackburn, San Jose, CA (US);
GTE Automatic Electric Laboratories, Incorporated, Northlake, IL (US);
Abstract
A regulating amplifier circuit with each transistor of a differentially connected pair thereof having a base electrode connected through an associated varistor to a first control transistor, the series combination of each varistor and the control transistor being driven by a variable DC bias voltage. The first control transistor is responsive to a gain control voltage for varying its conduction rate through the varistors and thus the gain of the circuit. A first resistor, the primary conduction path of a second control transistor, and a second resistor are electrically connected in series between a fixed DC supply voltage and a ground reference potential, with the second transistors collector voltage being coupled through an emitter follower as the bias voltage. Negative feedback of the first control transistors collector voltage to the second control transistors base electrode causes the magnitude of the bias voltage to vary for maintaining the first control transistor operating out of the saturation region over an extended range of input signal levels.