| 摘要 |
In addition to mapping the faults in a large memory, at high speeds, the apparatus classifies the mapped faults according to type. It is applicable where the memory comprises an array of semi-conductor chips and the accessed data words comprise bits from respective chips. Known data is entered into a memory and then the data stored in the memory is read out in a predetermined sequence. This is then compared with the known written data. The mismatches (errors) are counted on the two counters. Based on the number of errors counted, and the known sequence in which the data is read out, the type of fault is determined. The memory array is scanned first by successive word lines and then by successive bit lines within each of a number of chips. |
