Preliminary

This is a product that has fixed target specifications but are subject

Ramtron International Corporation

to change pending characterization results.

1850 Ramtron Drive, Colorado Springs, CO 80921

(800) 545-F-RAM, (719) 481-7000

Rev. 1.1

www.ramtron.com

June 2011

Page 1 of 13

FM25640C

64Kb Serial 5V F-RAM Memory

Features

64K bit Ferroelectric Nonvolatile RAM



Organized as 8,192 x 8 bits



High Endurance 1 Trillion (10



36 Year Data Retention at +75C



NoDelay™ Writes



Advanced high-reliability ferroelectric process

Very Fast Serial Peripheral Interface - SPI



Up to 20 MHz maximum bus frequency



Direct hardware replacement for EEPROM



SPI Mode 0 & 3 (CPOL, CPHA=0,0 & 1,1)

Sophisticated Write Protection Scheme



Hardware Protection



Software Protection

Low Power Consumption



250 A Active Current (1 MHz)



4 A (typ.) Standby Current

Industry Standard Configuration



Industrial Temperature -40C to +85C



8-pin “Green”/RoHS SOIC (-G)

Description

The FM25640C is a 64-kilobit nonvolatile memory

employing an advanced ferroelectric process. A

ferroelectric random access memory or F-RAM is

nonvolatile but operates in other respects as a RAM.

It provides reliable data retention for 36 years while

eliminating the complexities, overhead, and system

level reliability problems caused by EEPROM and

other nonvolatile memories.

The FM25640C performs write operations at bus

speed. No write delays are incurred. Data is written to

the memory array immediately after it has been

successfully transferred to the device. The next bus

cycle may commence immediately without the need

for data polling. The FM25640C is capable of

supporting up to 10

times more write cycles than EEPROM.

These capabilities make the FM25640C ideal for

nonvolatile memory applications requiring frequent

or rapid writes. Examples range from data collection,

where the number of write cycles may be critical, to

demanding industrial controls where the long write

time of EEPROM can cause data loss.

The FM25640C provides substantial benefits to users

of

serial

EEPROM,

in

a

hardware

drop-in

replacement. The FM25640C uses the high-speed SPI

bus, which enhances the high-speed write capability

of

F-RAM

technology.

The

specifications

are

guaranteed over an industrial temperature range of

-40°C to +85°C.

Pin Configuration

Pin Names

Function

/CS

Chip Select

/HOLD

Hold

/WP

Write Protect

SCK

Serial Clock

SI

Serial Data Input

SO

Serial Data Output

VDD

5V

VSS

Ground

Ordering Information

FM25640C-G

“Green”/RoHS 8-pin SOIC

FM25640C-GTR

“Green”/RoHS 8-pin SOIC,

Tape & Reel

CS

SO

WP

VSS

VDD

HOLD

SCK

SI

1

2

3

4

8

7

6

5