FM18L08-70-S Ramtron, FM18L08-70-S Datasheet - Page 5

• Manufacturer Part Number: FM18L08-70-S
• Description: F-RAM 256K (32Kx8) 70ns 3V
• Manufacturer: Ramtron

Specifications of FM18L08-70-S

• Memory Size: 256 KB
• Organization: 32 K x 8
• Interface: Parallel
• Access Time: 70 ns
• Operating Supply Voltage: 3 V to 3.6 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: SOIC-28
• Mounting Style: SMD/SMT
• Lead Free Status / Rohs Status: No

A second design consideration relates to the level of
V
forced to monitor V
backup. They typically block user access below a
certain V
battery with current demand from an active SRAM.
The user can be abruptly cut off from access to the
memory in a power down situation without warning.
FRAM memories do not need this system overhead.
The memory will not block access at any V
The user, however, should prevent the processor from
accessing memory when V
common design practice of holding a processor in
reset during powerdown may be sufficient. It is
recommended that Chip Enable is pulled high and
allowed to track V
cycles. It is the user’s responsibility to ensure that
chip enable is high to prevent accesses below V
min. (3.0V).
resistor on /CE which will keep the pin high during
Rev. 3.5
Sept. 2009
DD
during operation. Battery-backed SRAMs are
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level in order to prevent loading the
Figure 3 shows an external pullup
DD
DD
during powerup and powerdown
in order to switch to battery
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is out-of-tolerance. The
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level.
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power cycles assuming the MCU/MPU pin tri-states
during the reset condition. The pullup resistor value
should be chosen to ensure the /CE pin tracks V
a high enough value that the current drawn when /CE
is low is not an issue.
MCU/
Figure 3. Use of Pullup Resistor on /CE
MPU
V
R
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FM18L08
CE
WE
OE
A(14:0)
DQ
FM18L08
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