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. 10, 1992
Filed:
Sep. 11, 1990
Jon Huppenthal, Colorado Springs, CO (US);
Cray Computer Corporation, Colorado Springs, CO (US);
Abstract
A digital test system for functionally testing undiced ICs on wafers at relatively high test frequencies includes an improved probe card and interface assemblies. The probe card and interface assemblies each include a plurality of printed circuit boards laminated together as a single laminated structure. Equal length and equal impedance elongated micro strip test signal traces conduct the signals to and from a probe ring with a plurality of resilient probes physically and electrically in contact with the contact pads of the IC. Other circuit patterns includes a relatively large reference plane and a power plane of approximately equal size. The interface assembly performs selective I/O functions to electrically conduct input signals from a test signal generator to the probe card assembly and to electrically conduct response signals from the probe card assembly to the signal analyzer for determining the proper functionality of the IC. The printed circuit techniques assures a high degree of signal integrity, control over the signals at very high test frequencies, and efficiency in signal path routing.