Ramtron International

From Wikipedia, the free encyclopedia

Ramtron International Corporation
Type	Public (NASDAQ: RMTR}
Founded	1984
Headquarters	Colorado Springs, CO, USA
Industry	Semiconductors
Products	Nonvolatile F-RAM Memory Integrated Semiconductors
Employees	115
Website	www.ramtron.com

Ramtron International Corporation (NASDAQ: RMTR), located in Colorado Springs, CO, is the main supplier of F-RAM chips and integrated semiconductor products. The company sells serial and parallel ferroelectric random access memory (F-RAM) devices and Processor Companion devices that integrate a variety of common discrete analog and mixed-signal functions for processor-based systems. The company also sells non-memory devices enabled by F-RAM technology such as nonvolatile state savers and IC-based event data recorders. Ramtron is a fabless company with manufacturing partners in the United States and Japan and technology partnerships worldwide.

Contents 1 History 2 F-RAM Technology 3 F-RAM Technology Benefits 4 Products

[edit] History

Ramtron was founded in 1984 in Colorado Springs, Colorado. A prototype F-RAM device was unveiled at the International Solid State Circuits Conference (ISSCC) in 1988.

[edit] F-RAM Technology

F-RAM (ferroelectric random access memory) offers a unique set of features relative to other semiconductor technologies. Established semiconductor memories can be divided into two categories: volatile and nonvolatile. Volatile memory includes SRAM (static random access memory) and DRAM (dynamic random access memory), among others. RAM type devices are easy to use, offer high performance, but they share a common vulnerability: stored memory is lost when the power supply is removed.

An F-RAM chip contains a thin ferroelectric film of lead zirconate titanate [Pb(Zr,Ti)O3], commonly referred to as PZT. The Zr/Ti atoms in the PZT change polarity in an electric field, thereby producing a binary switch. Unlike RAM devices, F-RAM retains its data memory when power is shut off or interrupted, due to the PZT crystal maintaining polarity. This unique property makes F-RAM a low power, nonvolatile memory.

Like F-RAM, ROM (read only memory) is a nonvolatile memory that does not lose its data content when power is removed. Newer generation ROM, like EEPROM (electrically erasable programmable read only memory) and flash memory, can be erased and re-programmed multiple times, but they require high voltage and write very slowly. ROM-based technologies eventually wear out (in as little as 1E5 cycles), making them unsuitable for high-endurance industrial applications.

F-RAM has 10,000 times greater endurance and 3,000 times less power consumption than a typical serial EEPROM device, and nearly 500 times the write speed.

F-RAM combines RAM and ROM functionality into a single package that provide fast writes, high endurance and low power consumption.

[edit] F-RAM Technology Benefits

Fast write speed F-RAM performs read and write operations at the same speed. Because F-RAM writes data at bus speed, there are no delays before the written data becomes nonvolatile. Floating gate memories have long write delays of 5 milliseconds. F-RAM writes in nanoseconds.

High endurance F-RAM offers virtually unlimited write endurance, which allows it to write much more often than nonvolatile memory devices. Floating gate devices experience a hard failure and stop writing in as little as 1E5 cycles, making them unsuitable for write-intensive applications.

Low power consumption F-RAM operates without a charge pump, enabling low power consumption. Floating gate devices demand high voltage during write operations. F-RAM writes at the native voltage of the manufacturing process: 5V, 3V, or even less on more advanced processes.

[edit] Products

Ramtron's F-RAM product line features industry-standard serial and parallel interfaces; industry standard package types; and 4-kilobit, 16-kilobit, 64-kilobit, 256-kilobit, 1-megabit, 2-megabit, and 4-megabit densities.

In 1998, RAMTRON created ESDRAM [1], which was at the time the fastest synchronous dRAM. It was frequently used in place of fast SRAM in high performance embedded systems such as communications, DSP, and computer boards.