The EN29F040 is a 4-Megabit, electrically erasable, read/write non-volatile flash memory. Organized into 512K words with 8 bits per word, the 4M of memory is arranged in eight uniform sectors of 64Kbytes each. Any byte can be programmed typically in 10s. The EN29F040 features 5.0V voltage read and write operation, with access times as fast as 45ns to eliminate the need for WAIT states in high-performance microprocessor systems. The EN29F040 has separate Output Enable ( OE ), Chip Enable ( CE ), and Write Enable ( W E ) controls, which eliminate bus contention issues. This device is designed to allow either single (or multiple) Sector or full chip erase operation, where each Sector can be individually protected against program/erase operations or temporarily unprotected to erase or program. The device can sustain a minimum of 100K program/erase cycles on each Sector.