Semiconductor memory device using a plurality of semiconductor memory chips mounted in one system and a semiconductor memory system using a plurality of semiconductor memory devices

摘要

A semiconductor memory device has an address input circuit system capable of specifying a virtual memory space having a capacity larger than the actual storage capacity and a decoder system and sets the output terminal of a data output circuit system into a high impedance state when an address other than the previously specified addresses for the real memory space is specified. A plurality of semiconductor memory devices described above are used to construct a semiconductor memory system by commonly connecting corresponding ones of all of the input/output signal pins in parallel.