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FM25640_05 Datasheet, PDF (1/13 Pages) Ramtron International Corporation – 64Kb FRAM Serial Memory
FM25640
64Kb FRAM Serial Memory
Features
64K bit Ferroelectric Nonvolatile RAM
• Organized as 8,192 x 8 bits
• High Endurance 1 Trillion (1012) Read/Writes
• 45 Year Data Retention
• NoDelay™ Writes
• Advanced high-reliability ferroelectric process
Very Fast Serial Peripheral Interface - SPI
• Up to 5 MHz maximum bus frequency
• Direct hardware replacement for EEPROM
• SPI Mode 0 & 3 (CPOL, CPHA=0,0 & 1,1)
Description
The FM25640 is a 64-kilobit nonvolatile memory
employing an advanced ferroelectric process. A
ferroelectric random access memory or FRAM is
nonvolatile but operates in other respects as a RAM.
It provides reliable data retention for 45 years while
eliminating the complexities, overhead, and system
level reliability problems caused by EEPROM and
other nonvolatile memories.
Unlike serial EEPROMs, the FM25640 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. In addition, the product offers
substantial write endurance compared with other
nonvolatile memories. The FM25640 is capable of
supporting up to 1012 read/write cycles -- far more
than most systems will require from a serial memory.
These capabilities make the FM25640 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 FM25640 provides substantial benefits to users
of serial EEPROM, in a hardware drop-in
replacement. The FM25640 uses the high-speed SPI
bus, which enhances the high-speed write capability
of FRAM technology. The specifications are
guaranteed over an industrial temperature range of
-40°C to +85°C.
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
• “Green” 8-pin SOIC
Pin Configuration
CS
1
SO
2
WP
3
VSS
4
8
VDD
7
HOLD
6
SCK
5
SI
Pin Names
/CS
/HOLD
/WP
SCK
SI
SO
VDD
VSS
Function
Chip Select
Hold
Write Protect
Serial Clock
Serial Data Input
Serial Data Output
5V
Ground
Ordering Information
FM25640-S
8-pin SOIC
FM25640-G
“Green” 8-pin SOIC
This product conforms to specifications per the terms of the Ramtron
standard warranty. The product has completed Ramtron’s internal
qualification testing and has reached production status.
Rev. 3.0
Mar. 2005
Ramtron International Corporation
1850 Ramtron Drive, Colorado Springs, CO 80921
(800) 545-FRAM, (719) 481-7000
www.ramtron.com
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