Ferroelectric random access memory (FRAM) is widely known as a non-volatile, stand-alone memory technology that has been a part of the semiconductor industry for more than a decade.
In recent years, integrated circuit manufacturers have been considering FRAM as a strong contender for embedded, non-volatile memory, as an alternative to flash technology.
Today there are multiple memory technologies that have the potential to change the landscape of embedded processing. However, none so far have surfaced as a strong contender for replacing flash technology in microcontrollers (MCUs) until FRAM.
What is FRAM?
FRAM is non-volatile memory that has power, endurance and read/write speeds similar to commonly used static RAM (SRAM). Information stored in an FRAM cell corresponds to the state of polarization of a ferroelectric crystal that can hold its contents even after the power source is removed. This is what makes FRAM truly non-volatile. Also, since the energy required to polarize a crystal is relatively low when compared to programming a flash cell, FRAM writes are inherently lower power than flash.
Click on image to enlarge.
Here are a few typical applications that use microcontrollers with flash technology today. Let’s look at how leveraging FRAM-based MCUs, rather than flash-based MCUs, bring cost, energy and efficiency optimization.
A typical data logger application such as a temperature data logger can sample at rates anywhere between 1-1,000Hz. Now consider the write time of a single byte in flash memory is approximately 75µs.
In comparison, FRAM technology can be written to at a rate of about one byte every 125 nanoseconds. This is close to 1000 times faster than flash! Now consider the application reaches the end of a flash segment and needs to move to the next one, suddenly there is a 20