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. 29, 1992
Filed:
Dec. 05, 1991
Randal R Gingrich, Belleville, MI (US);
Nicholas L Difiore, Farmington Hills, MI (US);
Max H Behrens, Plymouth, MI (US);
Ford Motor Company, Dearborn, MI (US);
Abstract
A voltage-controlled amplifier employs an operational amplifier with negative feedback for setting the gain. A voltage variable resistance such as a junction-field-effect transistor (JFET) is employed as part of a variable voltage divider for controlling the amplifier gain. Resistors in series and in parallel with the JFET determine minimum and maximum resistances corresponding to upper and lower limits for the amplifier gain. Thus, multiple channels of an amplifier can be provided with closely matched characteristics even using separate JFETs in each separate channel which have unmatched characteristics.