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Melting Memory Chips In Mass Production
chill writes "Nature is reporting that 'South Korean manufacturer Samsung Electronics announced this week that it has begun mass production of a new kind of memory chip that stores information by melting and freezing tiny crystals. Known as phase-change memory (PCM), the idea was first proposed by physicists in the 1960s.' With transistor-equivalent cells only 20 nm wide, switching time is around 16 ns. The first target market is cell phones, but the companies behind the technology see applications in PCs, servers, and other devices as well."
i've been waiting for pcram to show it's head in consumer electronics for a while now. it has the advantages of being hundreds of times faster than flash along with having at least ten times the write-cycle life. it could turn out to be the OLED to DRAM's LCD.
the main disadvantage is that it's rather heat-sensitive, since writing is accomplished by melting crystals with a low melting temperature.
The new chips' lifetime? The impacts on overall computer heat? The energy required to use such memory? What is the expected RAM size to be available at first?
The article looks very scarce on details other than the technology itself which, honestly, doesn't say much about the final product at all.
help, my computer's frozen! nothings responding!
did you try reseting your memory?
how do I do that?
a few minutes with a hair dryer should do the trick.
I wonder how long they'd last. Apparently the crystal bond is very weak. I wouldn't want to lose my data because I dropped my cellphone. Perhaps I'm being paranoid?
This sound very similar to the phase change crystals in CDRW disks though obviously they are reading these electrically rather than optically since at 20nm you're well into the x-ray part of the spectrum.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
For the paranoid among us, this is really sweet. Leave the side of your computer's case open. When your front door suddenly gets knocked in and a bunch of feds start swarming into your living room, you just reach over and rub real hard on the chip with your finger. All your bits are melted.
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Depending on the liquid, it might be hotter.
Nerd rage is the funniest rage.
PCM is interesting stuff. Here's some info:
If these things run too hot, you'll literally have vaporware.
Samsung had a problem with K6X designated static ram chips. They would fail with the symptom being 'starts to work after a while' or 'starts to work when externally warmed'. They of course blamed the designer of the systems rather than offer to replace the defective parts. This failure happened across all packages.
It's a part you'll mostly find in embedded systems.
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And the Compy... just peed my carpet.
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Security for afterlife may be interesting. The more so if somebody thinks that their system or even the ram is bad. Unless it is physically ran through a fire, there will be something of use.
I prefer the "u" in honour as it seems to be missing these days.
is that the missing link between the electroweak force and gravity?
This has been tomorrow's hot technology for decades -- Ovshinsky has been trying to get traction with his phase change technologies since the late 60's! Ovonics?
Maybe this time?
And where are the other technologies that were going to displace the current leaders in the memory market?
Bubble memory?
FeRAM?
It would be nice to have another player in the game!
Does anyone know how hot we're actually talking to phase-change the material? I understand that the whole unit would probably get fairly warm during use, but on the scale of each bit, how much heat does it really take?
For fun, let's say hydrogen. Or tungsten. Your pick.
...the future crusty old bastards are already drinking the Kool-Aid.
I was just making a stupid play on some words in your subject.
Nerd rage is the funniest rage.
Steam computing... awesome! Then we need a way to get the "chuga-chuga-chuga" sound out of it as the work load increases. Oh Oh!, and a little steam whistle when an application unloads from memory.
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...that processors that support this type of memory will have to provide a Halt-and-Catch-Fire opcode?
Many CPU's in the past had Halt and Catch Fire instructions.
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Could PCRAM SSDs replace Flash SSDs? If so, I'd be rather happy as Flash's lack of longevity is one of the things keeping me from getting an SSD (well, the still enormusly high price point is the bigger one). Of course we don't have any real-world data but it still sounds interesting.
PCRAM's properties also make it sound interesting for archival storage. As long as you can keep the temperature at a sensible level it appears to be stable.
USE HOT GRITS WITH STATUE OF NATALIE PORTMAN (NAKED AND PETRIFIED)
I agree. I would like to learn more about the would like to give it a try if I can afford it and I'm quite excited about it.
So would that count as archival or volatile memory?
Perhaps the single most important advantage of PRAM has not even been mentioned yet. PRAM does not require the stupid block erase semantics of Flash--you can read or write as much or as little as you want, at whatever alignment, with no impact on performance. This also means that an SSD will be very simple, require no caches at all, and still have blazing fast write performance, even for synchronous writes.
PRAM will still require ECC algorithms, wear leveling, and bad block remapping, but on the spectrum of controller complexity, it is a lot closer to DRAM than Flash. (Incidentally, the same can be said of performance.) Reads and writes would still be buffered for queuing purposes, but this is very different from a cache; it is simply to allow requests to be pipelined from the storage controller.
Compared with the very simple constant time operations with PRAM, Flash is a dog. The controller must cache writes while it reads, erases, and otherwise shuffles blocks around. Moreover, as the controller operates with volatile memory, it must do this very slowly and carefully, or a power failure could severely corrupt the disk. (There are Flash SSDs with an onboard super capacitor to work around this, but they are obscenely expensive.)
Due to their inherent nature, even the best Flash SSDs have severely asymmetric read/write performance. The fact that only one company (Intel) has managed to produce a decent controller also betrays the immense complexity required to eek out even moderately acceptable random write performance. In my opinion, so called "SSDs" made with Flash don't even deserve that moniker, as they are more like a fast hard disk. (They still have a sort of geometry which constrains performance, and aren't anywhere near as fast as DRAM.)
PRAM will fix that, offering performance similar to a DRAM SSD. There are many companies banking on Phase-change RAM to displace Flash memory, Intel included. The wikipedia page has a lot more info, but basically, PRAM is superior to Flash in every way, except that the data on a prewritten chip won't survive a trip through the wave soldering machine.
The acceleration they suffer is the same (related to the height) but the movement quantity p=mv is not the same due to the m factor being a magnitude different in all case. So a BETTER comparison would be a matchbox car size, then the same weight but a different toy/substance. For example hard plastic toy will break , whereas plastic flexible toy will not for the same weight. Since it is using different kind of process and substance, you cannot readily say that because of size/weight it will be as shock resistant.
case in point : a glass ball smaller than the car box , and with less weight, has probably even less cahnce to arrive intact from the top of the building than the toy.
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Say we polarize the crystal using a specified voltage in it's 'melted' phase... Then to retrieve the value or 'polarization' we have a photon (created with a photon emitter) go through it effectively polarizing it (the photon) and then using a photon detector converting the photon back into a voltage
Congratulations, you've reinvented the CDR!
It's all rather confusing, really.
Only if you're talking about a place on Mercury, or about to be engulfed in vast swathes of basaltic lava flows. Don't use this if you place your datacenter in Yellowstone Park, folks.
In both cases, you have more serious problems than losing the contents of your storage. Like being dead.
ATM I'm just glad people quit talking about using ATM for packet networks and nobody needs ATM for Type 1 fonts any more so I can go to the ATM to get some money without brainlock.
The article talks about 512MB chips with a 16ns switching time. Assuming you switch multiple cells in parallel, from a word if you're using it as a memory, more if used as storage, and it has a 16ns cell switching time. Writing bit by bit would allow a 7.4MB/s write speed. Writing 64-bits at a time ups this to nearly 500MB/s. It's not a replacement for DDR3, not even mobile DDR, but could be used as an intermediary memory level between RAM and storage, or the storage itself once capacities increase (when it's made on sub-40nm processes).
The Wiki page talks about a 2006 64MB/512Mb Samsung PCRAM production, which is probably where you're getting the 64MB figure from.
From a cursory overview, it really looks like PCRAM is going to be big, in a few years, as a flash replacement that is simply better in every way. We will see what happens down the line of course, but the development is very promising.
I was wondering that myself. Aside from all the talk of losing your data if it gets too warm, what if the phone got really cold. Wouldn't that make it harder to heat up and write the data? Would it be temporarily unwritable when cold? Not a deal-breaker, but I just wonder.
J