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:
Nov. 27, 2007
Filed:
Jun. 17, 2005
Applicants:
Varadarajan Devnath, Santa Clara, CA (US);
Alan E. Segervall, Half Moon Bay, CA (US);
Inventors:
Varadarajan Devnath, Santa Clara, CA (US);
Alan E. Segervall, Half Moon Bay, CA (US);
Assignee:
National Semiconductor Corporation, Santa Clara, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03K 19/003 (2006.01);
U.S. Cl.
CPC ...
Abstract
A tunable impedance circuit is provided wherein at least one of a plurality of impedance elements is combined with at least another of the plurality of impedance elements to produce a composite impedance. A control voltage is used to determine how many of the impedance elements are to be combined to produce the composite impedance. A current that is substantially invariant over a range of operating conditions is caused to flow through a control impedance to produce the control voltage.