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:
Mar. 16, 1999
Filed:
Apr. 29, 1997
Michael R Ferland, Tualatin, OR (US);
Jeffrey D Currin, Pleasanton, CA (US);
Credence Systems Corporation, Fremont, CA (US);
Abstract
A circuit tester stimulates an analog circuit device under test (DUT) with a test signal and periodically digitizes a resulting DUT output signal to produce an output data sequence that may be analyzed to ascertain DUT operating characteristics. The tester is powered by a switching power supply that induces periodic noise spikes in the DUT output signal. To eliminate the influence of the noise spikes on test results, the period of the switching power supply noise is made coherent with the digitization period. The phase of digitization is then adjusted so that the tester avoids digitizing the noise spikes in the DUT output signal.