The Microchip AT28HC256 is a high-performance 256Kbit Parallel EEPROM available in both Industrial and Military temp ranges, offering access times to 70ns with power dissipation of 440mW. Deselected, CMOS standby current is less than 5mA. Accessed like static RAM for the read or write cycle without external components, it contains a 64-byte page register to allow writing of up to 64 bytes simultaneously. Features an internal Error Correction Circuit for extended endurance and improved data retention, in Military version. Optional Software Data Protection mechanism guards against inadvertent writes, and an extra 64 bytes of EEPROM enables device identification or tracking.

Additional Features:
32 Kbits x 8 (256 Kbit)
5V ± 10% Supply
Parallel Interface
150ns access time
self-Timed Erase and Write Cycles (10 ms max)
Page Write and Byte Write
Data Polling for end of write detection
Low Power Consumption:
Read / Write current 40 mA (Max)
Standby current TTL 2 mA (Max), CMOS 200 μA (Max)