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. 02, 1999
Filed:
Oct. 31, 1997
Applicant:
Inventors:
Robert H Noble, Longmont, CO (US);
Robert B Smith, Loveland, CO (US);
Assignee:
Hewlett-Packard Company, Pala Alto, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R / ;
U.S. Cl.
CPC ...
324523 ; 324539 ; 324607 ; 324603 ; 324763 ; 324 731 ;
Abstract
A method for determining whether a circuit under test is open is presented. A digital-to-analog converter is dithered to generate a known signal. This known signal is summed with an external attenuation signal which is brought into the system from a probe on the circuit under test. This summation is then measured by an analog-to-digital converter (ADC). If the known signal is not attenuated by the probe (i.e., the ADC measures essentially the known signal), we can conclude that the circuit is open.