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:
Apr. 25, 2000
Filed:
Jul. 16, 1997
Applicant:
Inventor:
Hideki Wakamatsu, Hyogo, JP;
Assignee:
Hewlett-Packard Company, Palo Alto, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R / ;
U.S. Cl.
CPC ...
324650 ; 324709 ; 324 7679 ;
Abstract
A method for stabilizing feedback loop in impedance measuring equipment involves determining a null loop transfer function of the impedance measuring device by utilizing multiple independent, known impedances. The phase characteristics of the null loop is measured for each multiple independent, known impedances. Based on the measured phase characteristics, the loop characteristic is determined with regard to impedances of arbitrary devices under test (DUTs). The best phase compensation amount is then computed for use over the entire range of DUTs.