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:
Mar. 20, 2007
Filed:
Dec. 10, 2002
Hiroyuki Takahashi, Kanagawa, JP;
Hideo Inaba, Kanagawa, JP;
Syouzou Uchida, Kanagawa, JP;
NEC Electronics Corporation, Kawasaki, JP;
Abstract
A test method and a test circuit which enable operations to be checked when the time interval between a refresh operation and a read or write operation is forcibly reduced. Timings for a read or write operation in a normal operation mode and in a test mode are determined on the basis of an address transition detection circuit. A timing for a refresh operation in the normal operation mode is set on the basis of a normal refreshing pulse signal generated by a refresh pulse generating circuit in response to a timing signal generated by a timer circuit. A timing for a refresh operation in the test mode is set on the basis of a first testing refresh pulse generation signal generated by a first testing refresh pulse generating circuit in response to the address transition detection signal. By controlling a timing for generating the first testing refresh pulse generation signal, it is possible to generate a read or write operation and a refresh operation so that there is a predetermined time interval between these operations.