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:
Apr. 12, 2011
Filed:
Sep. 30, 2008
Masaya Hirose, Kyoto, JP;
Takeshi Yamamoto, Osaka, JP;
Kinya Daio, Kyoto, JP;
Kenji Watanabe, Osaka, JP;
Masaya Hirose, Kyoto, JP;
Takeshi Yamamoto, Osaka, JP;
Kinya Daio, Kyoto, JP;
Kenji Watanabe, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
In a semiconductor device including an N-line M-stage shift register circuit operated at high speed of, for example, several hundreds MHz. Input circuits input a common test pattern to each of pairs of shift registers in, for example, two lines out of the N lines. A plurality of outputs of the pairs of shift registers in the two lines are compared in comparators, and the comparison results are output. The N-line M-stage shift register circuit and the comparators are operated in synchronization with a clock signal at several hundreds MHz. Hence, even when the circuit scale (area) of the N-line M-stage shift register circuit is increased to involve apparent wiring delay, a defect in the shift register circuit can be detected at an actual speed.