Integrated circuit memory devices having page flag cells which indicate the true or non-true state of page data therein and methods of operating the same

摘要

Integrated circuit memory devices with page copy flag cells include an array of memory cells and a plurality of flag cells coupled thereto which retain a flag to indicate whether a respective page of memory cells contains data copied in an inverted format from another page of memory cells. The memory cells and flag cells may comprise EEPROM cells and each page of memory cells preferably shares a word line with a respective flag cell. The flag may constitute a logic 1 (or logic 0) signal stored in the flag EEPROM cell to indicate whether the data in the corresponding page of memory is a true or an inverted copy of a page of data copied from another page at a different address. A page buffer is also provided to retain data read from a page of memory and read from a corresponding flag cell, and an exclusive OR gate for inverting the data outputted by the page buffer if the flag has been set and passing the outputted data unchanged if the flag has not been set.