| 摘要 |
A machine-practiced method for indicating memory chip failure modes. The individual memory cells on a chip are tested in accordance with standard practice. Each test has associated with it a respective one of the binary numbers 1, 2, 4, 8,.... An "error syndrome" is provided for each cell, and when that cell fails a particular test the respective binary number is added to the error syndrome for the cell. At the end of the sequence a chip map is printed. For each cell there is printed the respective error syndrome; that number identifies a particular group of tests which have been failed by the cell. By analyzing the error syndromes it is possible to identify individual cell failures, group cell failures and gross (total chip) failures. Moreover, the technique of the invention is a valuable diagnostic aid because it enables the causes of many failures to be ascertained.
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