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:
Jul. 15, 2008
Filed:
Aug. 21, 2006
Masaya Sumita, Hyogo, JP;
Akira Miyoshi, Osaka, JP;
Masaya Sumita, Hyogo, JP;
Akira Miyoshi, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
Each of D flip-flops (FFs)toconstituting a scan path circuit has a normal operation input circuit to be selected in a normal operation and a test operation input circuit to be selected in a test operation, and a control signal having an intermediate voltage between a supply voltage and a ground voltage is sent from a voltage generating circuitto the test operation input circuit of each FF in the test operation. In this case, the amount of an output change in data in each FF is smoother than that in the case in which the supply voltage is applied. Consequently, the delay time of the data is increased. The intermediate voltage to be applied to each FF in the test operation is determined based on a feedback signal sent from a test circuitfor checking whether scanned-out data have an error or not.