View 25c256 datasheet:

Advance Information CAT25C256 256K-Bit SPI Serial CMOS E2PROM FEATURES 100,000 Program/Erase Cycles 5 MHz SPI Compatible 100 Year Data Retention 1.8 to 6.0 Volt Operation Self-Timed Write Cycle Hardware and Software Protection 8-Pin DIP/SOIC and 20-Pin TSSOP Zero Standby Current 64-Byte Page Write Buffer Low Power CMOS Technology Block Write Protection SPI Modes (0,0 &1,1) – Protect 1/4, 1/2 or all of E2PROM Array Commercial, Industrial and Automotive Temperature Ranges DESCRIPTION to access the device. The HOLD pin may be used to The CAT25C256 is a 256K-Bit SPI Serial CMOS suspend any serial communication without resetting the E2PROM internally organized as 32Kx8 bits. Catalyst’s advanced CMOS Technology substantially reduces de- serial sequence. The C