Method of testing a semiconductor memory, and semiconductor memory with a test device

摘要

In order to test a semiconductor memory, a bit fail map is generated in that a predetermined data value is written to memory cells and subsequently read out and compared with the data value that has been written. The bit fail map is buffer-stored on the semiconductor memory in a memory bank other than the one that is currently being tested. Reliability of the test method is improved since defects in different memory banks can be regarded as independent of one another. It is advantageous for the bit fail map to be stored three times in different memory banks and for a majority decision to be taken during read-out.