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:
Feb. 03, 2009
Filed:
Sep. 18, 2006
John M. Long, San Jose, CA (US);
John M. Long, San Jose, CA (US);
FormFactor, Inc., Livermore, CA (US);
Abstract
Resistances of signal paths within a interconnect structure for linking input/output (I/O) ports of an integrated circuit (IC) tester to test points of an IC are measured by the IC tester itself. To do so the interconnect structure is used to link the tester's I/O ports to a similar arrangement of test points linked to one another through conductors. Drivers within the tester, which normally transmit digital test signals to IC test points via the I/O ports when the IC is under test, are modified so that they may also either transmit a constant current through the I/O ports or link the I/O ports to ground or other reference potential. The tester then transmits known currents though the signal paths interconnecting the tester's I/O ports. Existing comparators within the tester normally used to monitor the state of an IC's digital output signals are employed to measure voltage drops between the I/O ports, thereby to provide data from which resistance of signal paths within the interconnect structure may be computed.