| 摘要 |
PURPOSE:To test a mass-storage ROM by a memory tester on the market by providing a reference circuit which has the same functions and storage capacity with the memory(DUT) to be tested and using the result of comparison between the both as apparent readout data of the DUT. CONSTITUTION:The same address is sent from the memory tester 12 to the DUT 13 and reference circuit 14 and data are read out of corresponding memory cells of the both and compared by a comparing circuit 16, which outputs the comparison output. The same value with the output is written in the fail analytic memory in the memory tester 12 when said comparison result indicates coincidence, so when the result indicates dissidence, the memory ester 12 detects the abnormality and reports its address. Therefore, even when the DUT has large capacity, the fail analytic memory need not be increased in capacity and the memory tester on the market is used as it is to specify the trouble occurrence position of the DUT. |
