DESCRIPTION
The CAT25C128/256 is a 128K/256K-Bit SPI Serial CMOS E2PROM internally organized as 16Kx8/32Kx8 bits. Catalyst’s advanced CMOS Technology substantially reduces device power requirements. The CAT25C128/256 features a 64-byte page write buffer. The device operates via the SPI bus serial interface and is enabled though a Chip Select (CS). In addition to the Chip Select, the clock input (SCK), data in (SI) and data out (SO) are required to access the device. The HOLD pin may be used to suspend any serial communication without resetting the serial sequence. The CAT25C128/256 is designed with software and hardware write protection features including Block Lock protection. The device is available in 8-pin DIP, 8-pin SOIC, 16-pin SOIC, 14-pin TSSOP and 20-pin TSSOP packages.

FEATURES
■ 5 MHz SPI Compatible
■ 1.8 to 6.0 Volt Operation
■ Hardware and Software Protection
■ Zero Standby Current
■ Low Power CMOS Technology
■ SPI Modes (0,0 &1,1)
■ Commercial, Industrial and Automotive Temperature Ranges
■ 100,000 Program/Erase Cycles
■ 100 Year Data Retention
■ Self-Timed Write Cycle
■ 8-Pin DIP/SOIC, 16-Pin SOIC, 14-Pin TSSOP and 20-Pin TSSOP
■ 64-Byte Page Write Buffer
■ Block Write Protection
   – Protect 1/4, 1/2 or all of E2PROM Array