| 摘要 |
In the case that a refresh operation is carried out which is independent from an external access operation, both a data access method of a semiconductor memory device, and a semiconductor memory device are provided by which time suitable of each of these external access operation and refresh operation is set. While a time-measuring start signal "SIN" is entered into a path switching means, the path switching means is connected to either a first timer section or a second timer section under control of an external-access-operation-start-request signal REQ(O) and a refresh-operation-start-request signal REQ(I). Both the first and second timer sections measure both time "tauO" and time "tauI" to output a time-measuring stop signal "SOUT." The measuring time "tauO" corresponds to differential amplification time of a bit line pair when the external access operation is carried out, whereas the measuring time "tauI" corresponds to differential amplification time when the refresh operation is carried out. Alternatively, the measuring time "tauO" may be varied by reading/writing operations so as to be set. As a consequence, proper amplification time can be set every operation mode.
|
