Ramtron International Corporation, based in Colorado Springs, Colorado, designs, develops, and markets specialized semiconductor memory and integrated semiconductor solutions for a range of advanced metering applications.
Ramtron pioneered the integration of ferroelectric materials into semiconductor products, which enabled the development of a new class of nonvolatile memory products called FRAM (ferroelectric random access memory) products.
FRAM merges the advantages of multiple memory technologies into a single device that retains information without a power source. Fast write speed, high endurance, and low power consumption are among FRAM’s most compelling features that move it beyond the capabilities of older nonvolatile memory technologies. FRAM products provide cost-effective, quick and reliable data collection capability in a small footprint. They write significantly faster than EEPROM with unparalleled endurance and low power consumption.
With more than 30 million FRAM-equipped meters installed worldwide, Ramtron memory products have become the reliability and performance standard for advanced metering applications.
Optimised for Advanced Metering Infrastructure (AMI) applications that typically require frequent, fast, and/or low-power data writes, FRAM stores transaction logs and other nonvolatile data, writing virtually non-stop and preserving data even through sudden power loss. Ramtron’s serial FRAM memory products range from 4 kilobits (Kb) to 2 megabits (Mb) and are available with either a serial peripheral interface (SPI) or an industry-standard 2-wire interface (I2C). The 4Kb and 16Kb devices are commonly used in low-cost residential meters, while the 64Kb to 2Mb devices are suited to sophisticated three-phase commercial and industrial meters.
In addition to stand-alone memory, Ramtron offers integrated Processor Companion products which incorporate 4 to 256 Kb of FRAM with integrated peripherals such as a real-time clock (RTC), a watchdog timer, and a reset circuit. These devices are commonly used in time-of-use meters, which require that power usage be time-stamped. In such systems, the nonvolatile FRAM memory and the RTC record power usage and time-of-use. The watchdog timer and reset circuit enable integration with a microprocessor in the system.
FRAM offers three distinct benefits for an emerging class of digital utility meters that enhance energy distribution and management:
- No Delay™ reads/writes: FRAM writes data at bus speed, eliminating the need for a complicated data backup system in the event of power loss.
- Virtually unlimited endurance: FRAM collects data for an unlimited period without wearing out. In an electric meter FRAM can be written every second for the life of a meter. No other nonvolatile memory offers this capability. Less advanced designs that exclude FRAM can only afford to write the data when power is failing because alternative memory products wear out quickly if they are written too often.
- Low power consumption: FRAM devices are RAMs and do not require charge pumps and are, therefore, orders of magnitude lower in power during write cycles than floating gate devices such as flash and EEPROM. During battery-powered data collection, FRAM devices offer the lowest power operation of any memory solution available, making them ideal for a variety of data collection applications including water and gas meters.
For more information, visit www.ramtron.com