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:
Jun. 14, 2005
Filed:
Oct. 07, 2003
Bahram Fotouhi, Cupertino, CA (US);
Roubik Gregorian, Saratoga, CA (US);
Bahram Fotouhi, Cupertino, CA (US);
Roubik Gregorian, Saratoga, CA (US);
Exar Corporation, Fremont, CA (US);
Abstract
A technique for minimizing the effect of parasitic capacitance in a resistive gain amplifier. Instead of the resistors being formed directly over the substrate, or over an oxide of the substrate, a semiconductor element (e.g., an n-well) is used between the resistor and the substrate. For resistors in the input circuit, this semiconductor element is connected to the voltage input rather than ground. For the resistors in the feedback loop circuit, the semiconductor element is connected to the voltage output of the operational amplifier. The insertion of this semiconductor element provides the ability to programmably connect the parasitic capacitance to somewhere other than ground. By connecting the parasitic capacitance to the voltage input or voltage output, the ground connection is eliminated, eliminating the pole introduced by the parasitic capacitance.