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. 20, 2005
Filed:
Feb. 08, 2002
Takayuki Matsubara, Osaka, JP;
Akimitsu Shimamura, Kyoto, JP;
Takayuki Matsubara, Osaka, JP;
Akimitsu Shimamura, Kyoto, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In testing of a plurality of logic circuits having the same function and included in an integrated circuit, an address decoder makes two logic circuits having the same function simultaneously operate in response to an address signal. Try state buffers enter an enable state in response to a testing mode signal. Accordingly, the outputs of the two logic circuits are output to a signal line through the try state buffers. When the two logic circuits are both nondefective, a supply current cannot be measured by a current measuring unit, but when one of the logic circuits is defective, an excessive supply current is measured by the current measuring unit, and hence, it can be determined that one of them is defective. Accordingly, a plurality of logic circuits can be simultaneously found defective or nondefective by the IDDQ testing, resulting in reducing time required for the testing.