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. 26, 1998
Filed:
May. 28, 1996
Christopher W Mangelsdorf, Reading, MA (US);
Analog Devices, Inc., Norwood, MA (US);
Abstract
A variable gain amplifier includes an input transconductor having a transconductance that is variable in response to a first control signal, an output circuit having a transresistance that is variable in response to a second control signal and a gain controller responsive to a gain control signal x for providing the first and second control signals to the input transconductor and the output circuit. The amplifier has a voltage gain equal to the product of the transconductance and the transresistance. When the first control signal is a function (1+x) of the gain control signal and the second control signal is a function (1-x) of the gain control signal, the voltage gain of the amplifier is approximately an exponential function of the gain control signal.