This product conforms specifications per the terms of the Ramtron
Ramtron International Corporation
standard warranty. Production processing does not necessarily
1850 Ramtron Drive, Colorado Springs, CO 80921
include testing of all parameters.
(800) 545-FRAM, (719) 481-7000, Fax (719) 481-7058
www.ramtron.com
Rev 1.3
Feb. 2004
Page 1of 13
FM24C256
256Kb FRAM Serial Memory
Features
256Kbit Ferroelectric Nonvolatile RAM
•
Organized as 32,768 x 8 bits
•
High Endurance 10 Billion (10
10) Read/Writes
•
10 year Data Retention
•
NoDelay™ Writes
•
Advanced High-Reliability Ferroelectric Process
Fast Two-wire Serial Interface
•
Up to 1 MHz Maximum Bus Frequency
•
Supports Legacy Timing for 100 kHz & 400 kHz
Low Power Operation
•
5V Operation
•
200
µA Active Current (100 kHz)
•
100
µA Standby Current
Industry Standard Configuration
•
Industrial Temperature -40
° C to +85° C
•
8-pin EIAJ SOIC
Description
The FM24C256 is a 256-kilobit nonvolatile memory
employing an advanced ferroelectric process. A
ferroelectric random access memory or FRAM is
nonvolatile and performs reads and writes like a
RAM. It provides reliable data retention for 10 years
while eliminating the complexities, overhead, and
system
level
reliability
problems
caused
by
EEPROM and other nonvolatile memories.
The FM24C256 performs write operations at bus
speed. No write delays are incurred. The next bus
cycle may commence immediately without the need
for data polling. In addition, the product offers write
endurance
orders
of
magnitude
higher
than
EEPROM. Also, FRAM exhibits much lower power
during writes than EEPROM since write operations
do not require an internally elevated power supply
voltage for write circuits.
These capabilities make the FM24C256 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
combination of features allows more frequent data
writing with less overhead for the system.
The FM24C256 is available in a 8-pin EIAJ SOIC
package
using
an
industry
standard
two-wire
protocol. Specifications are guaranteed over an
industrial temperature range of -40°C to +85°C.
Pin Configuration
A0
A1
A2
VSS
VDD
WP
SCL
SDA
1
2
3
4
8
7
6
5
Pin Names
Function
A0-A2
Device Select Address
SDA
Serial Data/Address
SCL
Serial Clock
WP
Write Protect
VSS
Ground
VDD
Supply Voltage 5V
Ordering Information
FM24C256-SE
8-pin EIAJ SOIC
NOTE: Top side part marking is “FM24C256-S”
whereas “FM24C256-SE” is used only for ordering.