FM25040
4Kb FRAM Serial Memory
Features
4K bit Ferroelectric Nonvolatile RAM
• Organized as 512 x 8 bits
• High Endurance 10 Billion (1010) Read/Writes
• 10 year Data Retention
• NoDelay™ Writes
• Advanced high-reliability ferroelectric process
Fast Serial Peripheral Interface - SPI
• Up to 1.8 MHz maximum bus frequency
• Direct hardware replacement for EEPROM
• Supports SPI Mode 0 (CPOL=0, CPHA=0)
Description
The FM25040 is a 4-kilobit nonvolatile memory
employing an advanced ferroelectric process. A
ferroelectric random a
ccess memory or FRAM is
nonvolatile but operates in other respects as 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.
Unlike serial EEPROMs, the FM25040 performs
write operations at bus speed. No write delays are
incurred. Data is written to the memory array in the
cycle after it has been successfully transferred to the
device. The next bus cycle may commence
immediately without the need for data polling. In
addition the product offers substantial write
endurance compared with other nonvolatile
memories. The FM25040 is capable of supporting up
to 1010 read/write cycles -- far more than most
systems will require from a serial memory.
These capabilities make the FM25040 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 FM25040 provides substantial benefits to users
of serial EEPROM, in a hardware drop-in
replacement. The FM25040 uses the high-speed SPI
bus which enhances the high-speed write capability
of FRAM technology. Device specifications are
guaranteed over an industrial temperature range of
-40°C to +85°C.
This product conforms to specifications per the terms of the Ramtron
standard warranty. Production processing does not necessarily include testing of all parameters.
Rev. 2.1
Nov. 2003
Sophisticated Write Protection Scheme
• Hardware Protection
• Software Protection
Low Power Consumption
• 10 µA Standby Current
Industry Standard Configuration
• Industrial Temperature -40° C to +85° C
• 8-pin SOIC or PDIP
Pin Configuration
CS
1
8
VDD
SO
2
7
HOLD
WP
3
6
SCK
VSS
4
5
SI
Pin Names
/CS
/WP
/HOLD
SCK
SI
SO
VDD
VSS
Function
Chip Select
Write Protect
Hold
Serial Clock
Serial Data Input
Serial Data Output
Supply Voltage 5V
Ground
Ordering Information
FM25040-P
8-pin plastic PDIP
FM25040-S
8-pin SOIC
Ramtron International Corporation
1850 Ramtron Drive, Colorado Springs, CO 80921
(800) 545-FRAM, (719) 481-7000, Fax (719) 481-7058
www.ramtron.com
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