Description
The CAT28C257 is a fast, low power, 5 V−only CMOS Parallel EEPROM 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 auto−clear 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 self−timed write cycle. Additionally, the CAT28C257 features hardware and software write protection.

Features
• Fast Read Access Times: 120/150 ns
• Low Power CMOS Dissipation:
    – Active: 25 mA Max.
    – Standby: 150 A Max.
• Simple Write Operation:
    – On−chip Address and Data Latches
    – Self−timed Write Cycle with Auto−clear
• Fast Write Cycle Time:
    − 5 ms Max.
• CMOS and TTL Compatible I/O
• Automatic Page Write Operation:
    − 1 to 128 Bytes in 5 ms
    − 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