| 摘要 |
PROBLEM TO BE SOLVED: To easily measure the cycle of self-refreshing in a short test time. SOLUTION: This device is provided with a latch 12 which latches data of a refresh counter 7 and an output buffer 23 which outputs the output of the latch 12 to an external I/O. Consequently, when an oscillator 6 for constant- time refreshing, the output of this oscillator 6 is counted by the refresh counter 7, so its output is latched and outputted to the outside. Therefore, the value of the refresh counter 7 can directly be read out, so the cycle of the oscillator can be obtained from the value of the refresh counter 7 and the time for which the oscillator for refreshing is placed in operation. |
