FRAM - how does it work, and is this the end of the line for Flash RAM

[Mark R]

Been toying with a couple of circuits, and have come across some small FRAM (ferroelectric RAM) chips which are drop-in replacements for EEPROMs and FLASH.

The difference being that they are 'instant-write' whereas flash takes 1-10ms to write (depending on model), and that while flash wears out after 10k-100k writes, FRAM is supposed to last 10G writes

How does a ferro-electric RAM cell work, and what are disadvantages of this memory?

 

[dakels]

instant as in ns right? not some magic "Poof!" your data is written! although that would be a neat trick...

Typical RAM like DDR writes in about 5-10 ns IIRC.

All I know is that it's supposed to not require a power source to retain it's data but it needs more space to store data. More space for less data = bad for it's future in the memory busines I would think. google knows more then I do

 

[Shalmanese]

Is this the same as MRAM? If it is, then its still got the typical engineering problems that projects of this nature run into. Namely, high cost, low reliability, low volume. However, its destined to be the next big thing (TM) in RAM.

 

[dakels]

The technologies are similar but I don't think they work the same way.

I believe these 2 companies are the main proponents of the respective technologies. You should be able to find alot of info/white papers there.

FRAM - Ferroelectric Random Access Memory
Ramtron who happens to own a brand you may know = Mushkin.

MRAM - Magnetoresistive Random Access Memories
NVE

 

[tdowning]

I believe that the concept has been around for a long time, and that IIRC, each Bit of data is represented in a single Iron doughnut with two grid wires passing through it. those wires each pass through many doughnuts, forming a grid.

to write data you pass a refrence charce through one wire, and a variable (in direction IIRC) current in the other. this magnitizes the doughnut in a specific polarity. passing the refrence current again, causes the same variable current to occur in the cross wire, thus reading back the Bit.

And it is static, (that is it still remembers without power being applied, as opposed to dynamic RAM)

I believe that fero-magnetic memory was the major breakthrough that brought Project Whirlwind to fruition, (The first computer capable of doing things in real time. Up until that point computers were mostly only used to compute firing tables which were then committed to paper.)

 

[pm]

FRAM used to be called "core memory" when it was made from discrete components. Link here..

Another contender for the non-volatile crown which, IMO, takes the award for the most bizzare concept is ovonic memory in which a small section of a special type of material called a chalcogenide is electrically heated to over 600C at which point it melts and is then allowed to recrystallize. If it is heated slightly as it cools it recrystallizes one way, and if it's allowed to cool quickly it recrystallizes in another way. The type of crystallization results in different resistances which can then be read electrically.

A link on an article on ovonic memory.