Rapid electrification
worldwide has made data
collection a common
requirement in most electronic
systems. Today's designers of
electric power meters and data
collection systems face complex
demands as the push toward more
sophisticated utility distribution
management grows. Nonvolatile,
Ferroelectric Random Access
Memory (FRAM) offers three
distinct benefits to these
designers, creating an electronic
power meter with the memory
technology to capture data quickly
and continually, never wear
out and consume a very low level
of power.
First, FRAM is capable of
collecting data for an unlimited
period without wearing out. In an
electric meter, FRAM can be
written every second or minute for
the life of the meter. No other
nonvolatile memory offers this
capability. Less advanced designs
for digital meters must rely on
writing the data when power is
failing because other memory
products wear out very quickly if
they are written too often.
Ramtron offers FRAM devices
with industry standard two-wire
interfaces from 4Kb to 512Kb that
are ideal for electric meters. The
FM24C04 4Kb and FM24C16 16Kb
devices are commonly used in
low-cost residential meters, while
the FM24C64 64Kb, FM24C256
256Kb and FM24C512 512Kb
devices are suitable for advanced
three-phase commercial and
industrial meters. These products
are of sufficient bandwidth for
metering applications and are
easily integrated because of their
small package outline (eight-pin
SOIC or DFN).
In addition to their high
endurance, FRAM products operate
with very low power consumption.
The technology is capable of
producing devices with standby
current of less than one µa and
active current below 100µa. The
low power allows integration
without a significant increase in
the power budget.
The third benefit of Ramtron's
FRAM memories is speed. The
underlying technology is based
on RAM, like SRAM, rather than
ROM, like EEPROM and Flash. RAM
devices are much faster for reading
and writing, where write speed can
be less then 200 nanosecond (ns).
For example, Ramtron's FM22L16 is
a 256Kx16 nonvolatile RAM that
requires no battery backup. It
reads and writes with a 55 ns
access time. This device is ideal for
many types of data collection and
storage applications.
Why FRAM?
FRAM technology is a preferred
memory solution for data
collection. Several hundred
customers are already using FRAM
in production systems today;
making it the most widely used
advanced memory
technology available.
All current production memory
technologies use stored or trapped
charge to capture data.
Ferroelectric memory technology
stores state and is, therefore,
nonvolatile. Ferroelectric materials
have two unique properties:
......CONTD
