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:
Feb. 24, 1976
Filed:
Feb. 11, 1975
Takao Sumi, Tokyo, JA;
Masayuki Hongu, Komae, JA;
Sony Corporation, Tokyo, JA;
Abstract
A gain control circuit of the balanced type whose gain is linearly controllable over a wide range and wherein the DC level at the circuit output is maintained at a constant value regardless of variations of the controlling current. The gain control circuit is comprised of a first differential amplifier which receives an input signal differentially applied thereto, and a second differential amplifier connected in series with the first differential amplifier. Unidirectional conductors are connected to the outputs of the first differential amplifier as a load impedance and variable currents are supplied to the first differential amplifier outputs to control the currents flowing in the unidirectional conductors and thereby vary the load impedances presented by the unidirectional conductors. The amplified output signal is derived from an output of the second differential amplifier.