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:
Dec. 10, 2002
Filed:
Feb. 28, 2000
Howard M. Maassen, San Jose, CA (US);
William A. Fritzsche, Morgan Hill, CA (US);
Thomas P. Ho, Los Altos, CA (US);
Joseph C. Helland, San Jose, CA (US);
Schlumberger Technologies, Inc., San Jose, CA (US);
Abstract
A method and apparatus for calibrating tester timing accuracy during testing of integrated circuits. An ATE tester measures itself through reference blocks that have the same relevant dimensions as the integrated circuits to be tested. The number of reference blocks required is equal to the number of signal terminals on an integrated circuit to be tested being subject to timing calibration. A signal trace electrically connects a different signal terminal to a common reference terminal on each reference block. Each signal trace used should be closely matched both physically and electrically to the other signal traces used in the set of reference blocks, so that the electrical path length associated with each trace is nearly identical. To perform the timing calibration, the reference blocks may be mounted on a single fixture one at a time, or using multi-site fixtures, multiple reference blocks may be used in parallel. The fixture provides electrical connection of the reference block to the loadboard, and ultimately, the tester.