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:
Dec. 24, 1996
Filed:
Mar. 30, 1995
Gianluca Colli, Sannazzaro De Burgondi, IT;
Massimo Franciotta, Pavia, IT;
Rinaldo Castello, Arcore, IT;
SGS-Thomson Microelectronics S.r.l., Brianza, IT;
Abstract
An analog multiplier circuit includes three transconductance stages. One of the transconductance stages, receiving a first differential voltage, conducts a differential current responsive to the first differential voltage from the other two transconductance stages. The differential current changes the transconductance in the other two transconductance stages, which are cross-coupled with one another. The second differential input voltage is presented to the other two transconductance stages in parallel, resulting in an output differential current or voltage based on the product of the first and second differential input voltages. Each of the transconductance stages is implemented in BiCMOS, and each includes two differential legs, each having a MOS transistor receiving an input signal and a cascode bipolar transistor. Each transconductance stage also includes a reference leg which develops the drain-source voltage for the MOS transistors; the first transconductance stage differentially varies this drain-source voltage in the other two stages to produce the product.