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. 18, 1997
Filed:
Dec. 28, 1995
Isamu Takano, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A probe card includes an oscillator generating an AC signal, an averaged value detecting circuit receiving a signal outputted from a prescaler IC, for generating an averaged DC signal, and a plurality of switches for changing a flow of a signal among the IC tester, the prescaler IC, the oscillator and the averaged value detecting circuit. The switches is so controlled that the AC signal is supplied to the prescaler IC, and the signal outputted from the prescaler IC is supplied to the averaged value detecting circuit and converted to the averaged DC signal, whereby a non-defective/defective of the AC function of the prescaler IC is discriminated on the basis of the obtained averaged DC signal. The switches are also so controlled that a DC test signal is supplied from the IC tester to the prescaler IC and a DC output signal outputted from the prescaler IC is supplied to the IC tester. Thus, both an AC function test and a DC function test can be carried out on the prescaler IC in the form of a wafer by transferring only DC signals between the IC tester and the probe card.