DESCRIPTION
The CAT28C257 is a fast, low power, 5V-only CMOS Parallel E2PROM organized as 32K x 8-bits. It requires a simple interface for in-system programming. On-chip address and data latches, self-timed write cycle with autoclear and VCC power up/down write protection eliminate additional timing and protection hardware. DATA Polling and Toggle status bits signal the start and end of the selftimed write cycle. Additionally, the CAT28C257 features hardware and software write protection.

FEATURES
■ Fast Read Access Times: 90/120/150 ns
■ Low Power CMOS Dissipation:
    –Active: 25 mA Max.
    –Standby: 150 µA Max.
■ Simple Write Operation:
    –On-Chip Address and Data Latches
    –Self-Timed Write Cycle with Auto-Clear
■ Fast Write Cycle Time:
    –5ms Max
■ CMOS and TTL Compatible I/O
■ Automatic Page Write Operation:
    –1 to 128 Bytes in 5ms
    –Page Load Timer
■ End of Write Detection:
    –Toggle Bit
    –DATA Polling
■ Hardware and Software Write Protection
■ 100,000 Program/Erase Cycles
■ 100 Year Data Retention
■ Commercial, Industrial and Automotive Temperature Ranges