flash memory technology

Could MRAM Ultimately Replace DRAM? < PC

Everspin on Wednesday said its MRAM magnetoresistive random access memory is trickling into products that require reliable, fast non-volatile memory that can preserve data in the event of a power failure.

via Could MRAM Ultimately Replace DRAM? < Other PC Hardware Components, Technology, RAM, Components, Technology < PC World India News < PC

en:This is a simplified MRAM cell structure.
Image via Wikipedia

Magneto-Resistive RAM in the news

I haven’t heard any product announcements in a while. But it appears Everspin is keeping the faith and shipping real products to real manufacturers. I couldn’t be happier that it’s now on the market and competing for some product designs head to head with RAM and Flash memory. But in this instance it’s really competing against a whole other main stream product; static RAM.

The so-called SRAM was always used as a high speed read mostly cache that allowed a good sized buffer to stay close to the CPU. Static RAM caches were the easiest (but maybe not most cost effective) way to bump the speed of any Motorola or Intel cpu during their co-domination of the desktop market (Intel 386 and Motorola 680000). Stick an SRAM between the CPU and the motherboard, and voila 10-15% performance increase versus a straight through connection between CPU and the motherboard. And static RAM much like Flash based memory chips could also be used to hold data resident for many days powered down. But the cost versus Flash makes it much less competitive. However MRAM can also be used where you might have used a static RAM in the past. Current manufacturers are using it in place of static RAM in hard drive Host Bus Adaptors. This is not just a cost savings but a material savings as these days it is more common to back any mission critical drive electronics with a super-capacitor.

With Magnetic RAMs you can skip including the super capacitor and let the persistence built-in to MRAM do the rest (no need for refreshes or write/re-writes in the background). It makes me wonder if you also went with a super-capacitor to back everything locally and a Magnetic RAM module as well how big a mess that might give them to manage. But from a risk management standing, how much extra or how much less risk would you incur using MRAM plus Super-capacitors in your Disk Controller? I’m sure the cost of manufacture might not warrant the extra effort, but it would still be cool to see a statistical analysis comparing this ‘belt and suspenders’ extravagant setup versus just MRAM or just Super-capacitors.

science & technology technology

Revolutionise computer memory – New Scientist

So where is the technology that can store our high-definition home cinema collection on a single chip? Or every book we would ever want to read or refer to? Flash can’t do that. In labs across the world, though, an impressive array of technologies is lining up that could make such dreams achievable.

via Five ways to revolutionise computer memory – tech – 07 December 2009 – New Scientist.

Memory Chips on the decrease
RAM memory used to reign supreme in Dual Inline Packages (DIPS)

I used to follow news stories on new computer memory technology on the website. I didn’t always understand all the terms and technologies, but I did want to know what might be coming on the market in a couples of years. Magnetic RAM seemed like a game changer as did Ferro-Electric RAM. Both of them like Flash could hold their contents without the computer being turned on. And in some ways they were superior to Flash in that they read/write cycle didn’t destroy the memory over time. Flash is known to have a useful fixed lifespan before it wears out. According to the postscript in this article at New Scientist flash memory can sustain between 10,000 and 100,000 read/write cycles before it fails. Despite this, flash memory doesn’t seem to be going away anytime soon, and begs the question where are my MRAMs and FeRAM chips?

Maybe my faith in MRAM or Magnetic RAM was misplaced. I had great hopes for it exactly because so much time had been spent working on it. Looks like they couldn’t break the 32MB barrier in terms of the effective density of the MRAM chips themselves. And FeRAM is also stuck at 128MB effectively for similar reasons. It’s very difficult to contain or restrict the area over which the magnetism acts on the bits running through the wires on the chip. It’s all about too much crosstalk on the wires.

This article mentions something called Racetrack Memory. And what about Racetrack Memory so called RRAM? It reminds me a lot of what I read about the old Sperry Univac computers that used Mercury Delay Lines to store 512bits at a time. Only now instead of acoustic waves, it’s storing actual electrons and reading them in series as needed. Cool stuff, and if I had to vote for which one is going to win, obviously Phase Change and Racetrack look like good prospects right now. I hope both of them see the light of day real soon now.