Invention Grant
US08261139B2 Clear instruction information to indicate whether memory test failure information is valid
失效
清除指令信息以指示存储器测试失败信息是否有效
- Patent Title: Clear instruction information to indicate whether memory test failure information is valid
- Patent Title (中): 清除指令信息以指示存储器测试失败信息是否有效
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Application No.: US12709389Application Date: 2010-02-19
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Publication No.: US08261139B2Publication Date: 2012-09-04
- Inventor: Kenichi Fujisaki
- Applicant: Kenichi Fujisaki
- Applicant Address: JP Tokyo
- Assignee: Advantest Corporation
- Current Assignee: Advantest Corporation
- Current Assignee Address: JP Tokyo
- Agency: Chen Yoshimura LLP
- Main IPC: G11C29/00
- IPC: G11C29/00

Abstract:
A test apparatus includes a fail memory (AFM) for storing therein fail information in association with each of the addresses of a memory under test and a mark memory (CMM) for storing therein, in association with each of the addresses of the memory under test, validity information indicating whether the fail information stored in the AFM is valid. When the validity information read from the CMM in association with an address under test indicates that the fail information that has been stored in the AFM is invalid, the test apparatus overwrites the fail information stored in the AFM with the fail information that is newly generated by a current test. On the other hand, when the validity information read from the CMM indicates that the fail information is valid, the test apparatus updates the fail information stored in the AFM with the new fail information and writes the updated fail information back into the AFM. When overwriting the fail information that has been stored in the AFM with the new fail information, the test apparatus writes into the CMM the validity information that indicates that the new fail information is valid. Initialization of the AFM is performed in such a manner that, before and after the initialization, different validity information indicates validity of the fail information.
Public/Granted literature
- US20100235694A1 TEST APPARATUS AND TEST METHOD Public/Granted day:2010-09-16
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