Nonvolatile semiconductor memory which is connectable to a dram bus

Abstract

An electrically erasable and programmable nonvolatile memory device (EEPROM) such as a flash memory, is pin compatible with a dynamic random access memory device (DRAM), such that flash memory may be connected to a DRAM bus. Preferably, the flash memory is read and write timing-compatible with the DRAM read and write signals and is also preferably block read and block write timing compatible with DRAM block read and block write signals. The flash memory accepts signals to perform sleep and erase functions from signal lines of a DRAM bus which are not used by a DRAM. In order to perform a block erase, which is a characteristic of flash memory, the device preferably accepts an instruction to perform a block erase from signal lines of a DRAM bus which are not used by a DRAM and a block address for the block erase from the most significant bit address lines of the DRAM bus.