PRELIMINARY

FM25V40

Document Number: 001-87288 Rev. *A

Page 2 of 23

Contents

Pinouts .............................................................................. 3

Pin Definitions .................................................................. 3

Overview............................................................................ 4

Memory Architecture........................................................ 4

Serial Peripheral Interface – SPI Bus.............................. 4

SPI Overview............................................................... 4

SPI Modes................................................................... 5

Power Up to First Access ............................................ 6

Command Structure .................................................... 6

WREN - Set Write Enable Latch ................................. 6

WRDI - Reset Write Enable Latch............................... 6

Status Register and Write Protection ............................. 7

RDSR - Read Status Register..................................... 8

WRSR - Write Status Register .................................... 8

Memory Operation............................................................ 8

Write Operation ........................................................... 8

Read Operation ........................................................... 9

Fast Read Operation ................................................... 9

HOLD Pin Operation ................................................. 10

Sleep Mode ............................................................... 11

Device ID................................................................... 11

Endurance ................................................................. 12

Maximum Ratings........................................................... 13

Operating Range............................................................. 13

DC Electrical Characteristics ........................................ 13

Data Retention and Endurance ..................................... 14

Capacitance .................................................................... 14

Thermal Resistance........................................................ 14

AC Test Conditions ........................................................ 14

AC Switching Characteristics ....................................... 15

Power Cycle Timing ....................................................... 17

Ordering Information...................................................... 18

Ordering Code Definitions ......................................... 18

Package Diagrams.......................................................... 19

Acronyms ........................................................................ 21

Document Conventions ................................................. 21

Units of Measure ....................................................... 21

Document History Page ................................................. 22

Sales, Solutions, and Legal Information ...................... 23

Worldwide Sales and Design Support....................... 23

Products .................................................................... 23

PSoC® Solutions ...................................................... 23

Cypress Developer Community................................. 23

Technical Support ..................................................... 23