发明名称 |
Semiconductor memory device, refresh control method thereof, and test method thereof |
摘要 |
The present invention provides a semiconductor memory device which reduces current consumption in a standby state owing to a suitable refresh-thinning-out function, and a refresh control method thereof. When the refresh-thinning-out function is added while a refresh operation and an external access operation are being executed independently of each other, a refresh address counter outputs a refresh address Add(C) and inputs predetermined high-order bits thereof to a refresh-thinning-out control as a high-order refresh address Add(C) (m), where judgment as to whether the refresh operation is performed, is made. A refresh permission signal RFEN corresponding to the result of judgment is inputted to a word driver to activate and control the word driver. The process of judgment by the refresh-thinning-out control circuit can be embedded in an access time of a row system.
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申请公布号 |
US2006028893(A1) |
申请公布日期 |
2006.02.09 |
申请号 |
US20050249454 |
申请日期 |
2005.10.14 |
申请人 |
FUJITSU LIMITED |
发明人 |
NAKASHIMA MASAMI;KATO YOSHIHARU;KOMURA KAZUFUMI |
分类号 |
G11C7/00;G11C8/18;G11C11/401;G11C11/403;G11C11/406 |
主分类号 |
G11C7/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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