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:
Oct. 30, 1990
Filed:
Jul. 31, 1989
Horng-Jye Sun, Fremont, CA (US);
Bruce C Morley, Cupertino, CA (US);
Teledyne MEC, Mountain View, CA (US);
Abstract
A MMIC variable slope gain-equalizer varies the conductance of depletion mode Schottky gate FETs to controllably insert frequency dependent resonant members in a modified bridged-T configuration. Resistors connected from circuit input port to output port define the arms of the 'T' and a T-node to which a first frequency dependent resonant member is connected in series with a first FET. A second FET and a second frequency dependent resonant member are each connected in series between the circuit ports, bridging the T. Preferably a third frequency dependent resonant member is series connected with the second frequency dependent member. Each frequency dependent resonant member resonates at about the highest frequency of interest, typically about 18 GHz. When the first FET is on and the second FET off, maximum attenuation at lower frequencies is inserted into the circuit, and when the first FET is off and the second FET on, minimum attenuation is inserted at lower frequencies. Intermediate levels of FET conductivity produce intermediate levels of frequency dependent attenuation. In a first embodiment, FET conductivity is controlled by two push-pull control voltages. A second embodiment uses a single control voltage to vary conductivity. The first embodiment operates at about 0-18 GHz, while the second embodiment operates at about 2-18 GHz. Each embodiment realizes a variable slope gain-versus frequency temperature function of between about -0.6 dB/GHz to about +0.2 dB/GHz with a 0 to +3VDC control voltage change.