Intel's Haswell Moves Voltage Regulator On-Die 237
MojoKid writes "For the past decade, AMD and Intel have been racing each other to incorporate more components into the CPU die. Memory controllers, integrated GPUs, northbridges, and southbridges have all moved closer to a single package, known as SoCs (system-on-a-chip). Now, with Haswell, Intel is set to integrate another important piece of circuitry. When it launches next month, Haswell will be the first x86 CPU to include an on-die voltage regulator module, or VRM. Haswell incorporates a refined VRM on-die that allows for multiple voltage rails and controls voltage for the CPU, on-die GPU, system I/O, integrated memory controller, as well as several other functions. Intel refers to this as a FIVR (Fully Integrated Voltage Regulator), and it apparently eliminates voltage ripple and is significantly more efficient than your traditional motherboard VRM. Added bonus? It's 1/50th the size."
Update: 05/14 01:22 GMT by U L : Reader AdamHaun comments: "They already have a test chip that they used to power a ~90W Xeon E7330 for four hours while it ran Linpack. ... Voltage ripple is less than 2mV. Peak efficiency per cell looks like ~76% at 8A. They claim hitting 82% would be easy..." and links to a presentation on the integrated VRM (PDF).
excited (Score:5, Funny)
come guys, comment, so I know how excited I should be
Re:excited (Score:4, Funny)
Re:excited (Score:5, Funny)
All good guys, he is gone. We can go back to our regular insightful, interesting and funny posts again.
sinking heat? (Score:4, Interesting)
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The summary says 76% efficiency. That would mean 24% of the energy you put into the chip is turned into heat by the voltage regulator. Sounds like a valid concern to me.
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What sort of construction reduce waste by adding cells?
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And why would it do that? A given voltage drop multiplied by the current through it equates to a certain wattage of heat dissipation, regardless of the size of the package.
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Your broad generalization is only if it is a linear regulator. Switch-mode regulators change the game. TFA doesn't seem to indicate which it is.
Re:sinking heat? (Score:5, Informative)
Re:sinking heat? (Score:4, Insightful)
The voltage regulation issue can easily be solved by having a feedback connection from the die to the external VRM.
There are only two benefits I can see:
1) Higher voltage in to the chip means lower current, which saves power. You I*R formula is slightly wrong, its actually I^2 * R, double the current means 4x the power loss.
2) Lower system cost. the more crap that gets stuffed on the die/in the chip, the less is required on the board. That means fewer components, smaller board area and quicker assembly.
There are of course other benefits that only benefit Intel
a) Fewer external components means they can charge more for their chip without effecting system cost.
b) smaller system = happier customer = will pay more
c) If it does actually result in lower power, then you get more performance or more battery life = customer will pay more
No it's about ripple (Score:5, Insightful)
If you'd read at least the summary, the benefit would be less ripple. Because it takes time to get the feedback voltage to the external VRM, there would always be ripple if power demands would fluctuate fast enough. In a typical CPU on a typical load, you get a lot of power load changes, so you'd get a lot of ripple. Ripple means that ultra low power circuitry will be harder to implement and hit limits earlier, since it is more dependent on precise voltages.
Power saving wouldn't be relevant, if you are looking at the power loss in the circuit board traces to the CPU. The efficiency of the internal regulator is lower than that of external voltage regulators so it would probably consume even more power.
System cost would be higher. Other components on the main board still require regulated voltages, so no components would be saved there.
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System cost would be higher. Other components on the main board still require regulated voltages, so no components would be saved there.
This is actually something you're wrong about. A modern CPU require 3 distinct voltages separate from all other devices on the motherboard. The bus, northbridge, memory, and every other non-cpu component will run at different voltages. About half of the regulators that take up real-estate directly around the CPU serve only the CPU. These components could be saved.
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I figured that it must be that way, but with the power required by a CPU such a regulator must either very noisy and/or require substantial capacitance and/or use ridiculously high frequencies.
So. Filtering? These might be the most expensive mass-produced caps in the world if they're also on-die.
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I rather doubt Intel managed to cram the inductor on-chip too, so doesn't that defeat the point?
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Don't underestimate Intel's ability and will to put all kinds of things on-chip.
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Watts is used to measure heat.
http://en.wikipedia.org/wiki/Thermal_resistance [wikipedia.org]
The unit is "degrees per watt". As in "5C/W" = "this heat sink will rise by 5 degrees dissipating 1 watt"
Heat (Score:4, Interesting)
Intel refers to this as a FIVR (Fully Integrated Voltage Regulator), and it apparently eliminates voltage ripple and is significantly more efficient than your traditional motherboard VRM. Added bonus? It's 1/50th the size."
I have yet to come across a voltage regulator that doesn't run hot. Typically, it's one of the hottest components in an electrical circuit. And we're integrated this into a slab of silicon already well-known for getting so hot it can catch fire?
Can someone please tell me why this is a good idea, because all of my experience in electrical engineering says that when things heat up, they become more unstable and prone to failure, and the one thing you do not want going critical is your voltage regulator. If that goes, the whole computer catches fire.
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Sorry, but I design quite a lot of switch mode regulators for my own hardware design, and there are several concerns here:
- the efficiency of 76% they claim is abysmally low, my regulators are never below 80% in their operating range, and often above 90%, with peaks in the 96-97% range.
- switch mode regulators need an inductor, and inductors need ferrite or iron cores, which is not going to happen on a silicon die. External inductors are much better
but low loss inductors for large currents are large, for fu
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I do SoCs with integrated regulators now.
Their inductors are on-chip using extra thick metal levels. But "extra thick" levels on sub-20nm chips are still pretty damn thin, meaning high r/square, so the Q they can get out of the inductors is pretty low, especially since the configuration they use (linear coupling rather spiral) will also limit their available Q. That's what's driving their efficiencies down from what you're used to in discrete buck regulators.
The big advantage of integrating this is that you
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Most likely, because it's integrated into the CPU itself, the voltage regulator can be made more efficiently and thus save power and heat etc. Discrete parts have their limitations, and doing it on-die might just mitigate that.
I'm not sure that follows. For transistors doing computation, the efficiency saving is by reducing the amount of current that they have to switch. In this case, all they're really doing is building a very large MOSFET onto the die itself along with a bit of other gubbins.
Also, the eff
Re:Heat (Score:4, Informative)
You're going to run into that heat anyway, whether it's on the motherboard in general or on the CPU. You can't win. But at least it's better to have heat build-up near a heat-sink, so for high-power conditions it might actually be better to put it on the CPU. I'm also an electrical engineer, but thermals are really a mechanical engineer's realm, so I can't run numbers for you.
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Being 1/50th the size it will be welcome on mobile devices. Not sure that its a good thing for your gaming desktop.
Re:Heat (Score:5, Informative)
Being 1/50th the size it will be welcome on mobile devices. Not sure that its a good thing for your gaming desktop.
That 84 watts is going to rip through your mobile device's battery pretty damn fast.
Compared to a traditional regulator? (Score:2)
Being 1/50th the size it will be welcome on mobile devices. Not sure that its a good thing for your gaming desktop.
That 84 watts is going to rip through your mobile device's battery pretty damn fast.
Don't we need to compare it to a traditional regulator implementation before we come to that conclusion? Assuming pretty damn fast means faster than current Atom based devices.
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Being 1/50th the size it will be welcome on mobile devices.
It's not clear how they measure "1/50th the size". I could be wrong but it sounds like marketing hype. With a switching regulator the inductors and capacitors generally take up much more real estate than the chip. If they have some magic way to reduce the inductor and capacitor sizes it isn't mentioned in the article (and that would be a much bigger deal than just putting the regulator on the die).
Re:Heat (Score:5, Interesting)
You can reduce the inductor and capacitor sizes a lot by increasing the switching frequency. Of course doing so will likely increase your switching losses but it may still be worth it if it lets you put the regulator closer to the load. Especially given the ever lower voltages that modern chips are running at.
Re:Heat (Score:5, Interesting)
You can reduce the inductor and capacitor sizes a lot by increasing the switching frequency.
But you can do that w/ an external regulator too. Apparently the secret is on-chip inductors. Now that's impressive. I'm surprised that some of the "analog" companies making switchers didn't come up with that first. I know Intel has good fab tech, but this seems more like the sort of funky thing analog guys would come up with first.
http://www.psma.com/sites/default/files/uploads/tech-forums-nanotechnology/resources/400a-fully-integrated-silicon-voltage-regulator.pdf
Re:Heat (Score:5, Informative)
Intel might be the first to do it on a CPU die, but they're not the first to do on-silicon inductors by any stretch. Switching regulators with inductors on silicon have been commercially available for several years now. The R-78 [digikey.com] and MIC33030 [micrel.com], for example, are drop-in replacements for linear regulators, with all components on die.
The real question in my mind is why anyone still uses linear regulators for anything, but I digress.
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That R-78E3.3-0.5 looks useful... the raspberry pi uses a rather inefficient linear regulator to take the 5v input down to 3.3v. An NCP1117. Can't just replace it with an R-78, as the minimum input voltage is 6V, but if you're running it off of something higher... yes. This component may be of use to me.
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Actually the analogue guys like Texas and Linear do make switching regulators with on-board inductors that are pretty small. Small enough that they could be integrated into a typical desktop CPU form factor.
Unfortunately TFA is light on details. 1/50th the size of what? A mains transformer? A SOT-23 IC?
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But you can do that w/ an external regulator too. Apparently the secret is on-chip inductors. Now that's impressive. I'm surprised that some of the "analog" companies making switchers didn't come up with that first. I know Intel has good fab tech, but this seems more like the sort of funky thing analog guys would come up with first.
They did.
I did a semiconductor course on analog CMOS as an undergrad over 10 years ago. It's interesting because the CMOS processes are typically adapted for digital electronics,
Re:Heat (Score:5, Interesting)
If you core requires 1V and 90 watts you need to transfer 90A through your PCB traces, up in to the chip, across the bond wires (if there are any) and on to the die.
If your die has a regulator on board and accepts 12V instead, and is 80% efficient you only need to transfer 9.4A. You've just lowered your resistive losses by about 100x. If the connection between the external VRM and die is 0.001ohms, at 90A you waste 8.1W. at 9.4A you waste 0.088W.
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Re:Heat (Score:5, Informative)
My suspicion(if only for die-space reasons, it isn't purely cosmetic that contemporary VRMs occupy a substantial amount of board space) is that is this a 'marketecture' summary of Intel moving some additional voltage adjustment and power gating functions on die, to support dynamic adjustment of power to the greater number of components(multiple CPU cores, possibly independently clocked, GPU, RAM controller, PCIe root, etc.); but we'll still see a bunch of chunky power silicon under serious heatsinks clustered around the CPU socket.
Given that much of the contemporary power savings are achieved by superior idling, rather than absolute gains in maximum power draw, Intel is either going to have to keep moving power regulation on die, or start dedicating even more pins to tiny voltages at nontrivial currents, with the associated resistive losses; but that won't necessarily change the fact that the circuitry that brings the 12v rail down to what the CPU wants is a pretty big chunk of board.
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My suspicion(if only for die-space reasons, it isn't purely cosmetic that contemporary VRMs occupy a substantial amount of board space) is that is this a 'marketecture' summary of Intel moving some additional voltage adjustment and power gating functions on die, to support dynamic adjustment of power to the greater number of components(multiple CPU cores, possibly independently clocked, GPU, RAM controller, PCIe root, etc.); but we'll still see a bunch of chunky power silicon under serious heatsinks clustered around the CPU socket.
That's the only plausible thing I could come up with as well. The control logic could go into the CPU, but I don't see how pulling 12V down to fractions of a volt is going to happen on the die itself without it burning a hole through the board; heatsink or not, you can't escape Ohm's Law.
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Who said they're going to keep it at 12 volts? A VRM can also be the transformer, but it doesn't have to be. They could ramp down the voltage on the board just like they always did and just have a VRM on the chip that is maintaining a steady voltage. If you read the article they are barging about how little fluctuation they are getting. So it seems like what they are doing here is adding basically an extra regulator on chip so they can have extremely stable voltage. I'm guessing as small as things are getti
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Who said they're going to keep it at 12 volts? A VRM can also be the transformer, but it doesn't have to be. They could ramp down the voltage on the board just like they always did and just have a VRM on the chip that is maintaining a steady voltage. If you read the article they are barging about how little fluctuation they are getting. So it seems like what they are doing here is adding basically an extra regulator on chip so they can have extremely stable voltage. I'm guessing as small as things are getting now, just the trip across the motherboard can have noticeable fluctuations on supply voltages due to EM interference and temp fluctuations, so having a regulator on the chip lets them get more precise. Maybe that precision will let them do some magic on the chip to increase performance or something?
Or they are finding those Chinese made MB motherboards have such poor regulators, that they have to do some final regulation on the die to keep things stable?
This is probably also driven by a desire to start putting higher horsepower CPUs into smaller things like tablets.
Re:Heat (Score:5, Informative)
Ohm's law is completely irrelevant to this situation *in the form you describe*. "Burning a hole through the board" would be possible and a simple function of Ohm's law only if they were using a linear regulator to generate the Vcore. But VRM's have been switching DC/DC converters since the 486 days. They achieve a voltage conversion by switching the incoming voltage on and off *very fast*, which results in an output voltage that's a function of the input voltage and the duty cycle of the on/off switching. An inductor (current-smoothing) and capacitor (voltage smoothing) give a nice clean DC voltage.
The differences between on-motherboard VRMs and this new in-package (it's technically a separate chip...) are significant. First off, physically moving it closer means that you're not sending 100+ Amps of current over the 3-4 centimeters of generally very thin copper traces on the PCB, they're sent millimeters through die-bond wires, or even through a solid substrate (no idea what Intel does at that level). There's your Ohm's law coming into play at that level, but the power losses there are relatively minimal since you're talking maybe a few tenths of an ohm. Die-bond wires are going to drop that to 10's of milli-ohms probably, so nothing major but still a positive effect.
The main reason this will generate a lot less heat is because of the *frequency* of the switching. Because this on-board VRM is so much smaller, it can switch the input faster (shorter wires, less parasitic capacitance, less ringing, etc.). This in turn means smaller value components required, e.g. the switch from the monster inductors seen on the motherboard (at maybe 1-2MHz switching) in the slide to the tiny chip-scale inductors on the FIVR (at 10's or 100's of MHz). The end result of all of this is that switching losses get significantly smaller. It's those losses that create heat local to the regulator. If they can for example go from an 80% efficient VRM to an 90% efficient FIVR for a 100W CPU load, they reduce the switching losses from 25W to 11.1W.
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. This in turn means smaller value components required, e.g. the switch from the monster inductors seen on the motherboard (at maybe 1-2MHz switching) in the slide to the tiny chip-scale inductors on the FIVR (at 10's or 100's of MHz).
From the linked pdf - Programmable switching frequency 30MHz to 140MHz
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The big problem with bringing 12V on-chip is not Ohm's law. It is silicon's breakdown voltage at 22nm.
Trace-to-trace and channel/gate breakdown voltages can be addressed by patterning high-voltage areas with wider insulation gaps but that does not address insulation between metallization layers. It would be feasible but it would also make the fabrication process a fair bit more complex to accommodate the different insulation thickness in the high-voltage area vs the digital stuff.
I'm guessing the ~2.5V happ
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The big problem with bringing 12V on-chip is not Ohm's law. It is silicon's breakdown voltage at 22nm.
From the linked PDF - "90 nm technology for test devices". It looks like it's not on the same silicon as the actual processor, but rather stacked on top..
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The control logic could go into the CPU, but I don't see how pulling 12V down to fractions of a volt is going to happen on the die itself without it burning a hole through the board; heatsink or not, you can't escape Ohm's Law.
I think that may be the point: at some point you have to pull 100W down to fractions of a volt (i.e. hundreds of amps). By doing it on die, it is closer to where you want it to be so you don't have the problem of shipping hundreds of amps quite such long distances.
Re:Heat (Score:5, Funny)
you can't escape Ohm's Law.
Actually you can. It's called a switching power supply.
In other news, a Nobel Prize in Physics was awarded to Anonymous Coward of Slashdot today, after discovering that the laws of physics do not apply to switching power supplies... His next research proposal is on solving the energy crisis by designing keyboards to detect when someone is angry and then increasing the key resistance by piezoelectric effect to generate energy. While it would generate only marginal amounts of power when used by 99.975% of the population, it was recently discovered that the remainder are actually Linux and Apple fanboys who, if fed a regular diet of dismissives via their computer screen, will so furiously hit the keyboards that power for entire cities is easily achievable.
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Ohm's law goes out the window as soon as inductance becomes a nontrivial factor.
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Actually, no real device is ohmic at all. Even a resistor will heat up with increasing current causing an increased resistance that is non-linear. For us EEs, ohmic devices are our massless pullies and frictionless inclines.
Re:Heat (Score:5, Insightful)
Actually, no real device is ohmic at all. Even a resistor will heat up with increasing current causing an increased resistance that is non-linear. For us EEs, ohmic devices are our massless pullies and frictionless inclines.
I'm not a certified EE, but I have built electronic circuits. I know there's a lot of ways to 'cheat' on paper; switching power supplies don't get rid of ohm's law though, they're simply more efficient. Ohm's law is about the relationship between resistance, voltage, and current. Those relationships are derived from the physics about electron exchange between different materials. Now yes, capacitors and inductors both run 90 degrees out of phase between voltage and current so it can appear to be violating ohm's law, but if you apply a correction factor you'll see it's pretty close to parity. When you get down to really small discrete components, like a transitor for example, measurement inaccuracy and time domains will really start to screw with you, but ohm's law still holds even down to that scale.
Ohm's law is the reason for these changes Intel is making: An attempt to remove parasitics from the circuits, which all boil down to resistance; Whether it's phase-shifted forward because of capacitors, or backwards because of inductors, or because of components that create those effects, doesn't really matter.
Now you're right, a purely ohmic device doesn't exist. Even resistors can generate small amounts of phase shift. But that doesn't make them "massless pullies" or "frictionless inclines". Ohm's law is still useful for the same reason the OSI 7 layer model is still useful, despite no network yet having been designed that perfectly adheres to it...
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What an absurd statement. Just because a device has non-linear characteristics doesn't mean that V=IR is any less useful.
LEDs are non-linear yet we use V=IR as way to determine the required compliance of a current source, or what resistor you need if you go down the easy voltage source route. Or an example closer to home, the MOSFET may have a non-linear and time changing characteristic while turning on, but the regulator's power efficiency is none the less determined by the I^2R losses. That doesn't change
Re:Heat (Score:5, Interesting)
Well even at 10W I'm wondering how they'll address the heat.
With the density of circuits in the adjacent silicon I would wonder how they're providing enough isolation to prevent it from becoming a very small brick.
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Considering that they've already started shipping an actual product, perhaps you should switch modes--from skeptic to sleuth. Start from the proposition that (a) it's possible or (b) they're leaving something out of the marketing jargon. There are a million ways they could do it wrong, and likely only a few ways to do it right. If you start from the proposition that Intel is shipping a working product, then it should be much easier to figure out.
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And I have a couple of Bulldozer AMDs that run up to 125W that still doesn't mean that you can't cook something or shorten its life. Since these will be 10W processors it will be interesting to see how well they stack up against their predicessors because if they are favorable in comparison then it will be a lot less heat and a lot less noise in desktops.
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Are you serious? Essentially all of the power going into the CPU is coming out of it as heat already. That's 35-100+ watts of heat already being dissipated. And you're worried about another 10 watts?
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I'm not an EE so I won't pretend to fully understand this particular case but I like it when tech companies reach a bit and try something hard. This may or may not be a good idea but I'm still excited about it.
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I'm not an EE so I won't pretend to fully understand this particular case but I like it when tech companies reach a bit and try something hard. This may or may not be a good idea but I'm still excited about it.
Thats what she said.
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May be that they still use discrete FETs, it's just control circuitry is on die now. (I'm speculating)
That's an interesting question. They can make a FET with as big a voltage and current rating as they want by just making it many times the size of a logic FET. But they also need thicker gate oxide to prevent Vdg breakdown at multiples of the normal logic operating voltage. Not sure how they would do that. It could add a process step, which would make it expensive.
Re:Heat (Score:5, Informative)
Can someone please tell me why this is a good idea
The long story is here (PDF) [psma.com]. Motherboard will still do the heavy lifting from 12V to 2.4V, but the integrated VRM will distribute it. Advantage is extremely clean, fine-grained, low-latency and flexible power supply to deliver exactly as much power to where it's needed and probably - this is just speculation on my part - allowing the CPU to work on a wider range of voltages since there's less noise and ripple so you don't need the same tolerance limits. It sounds perfect for smart phones, tablets and laptops that are primarily battery-limited, nice to have for average machines but potentially an issue for overclockers. All you need is cooling though, it shouldn't limit overclocking if you can keep the temp down.
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Intel refers to this as a FIVR (Fully Integrated Voltage Regulator), and it apparently eliminates voltage ripple and is significantly more efficient than your traditional motherboard VRM. Added bonus? It's 1/50th the size."
I have yet to come across a voltage regulator that doesn't run hot. Typically, it's one of the hottest components in an electrical circuit. And we're integrated this into a slab of silicon already well-known for getting so hot it can catch fire?
Can someone please tell me why this is a good idea, because all of my experience in electrical engineering says that when things heat up, they become more unstable and prone to failure, and the one thing you do not want going critical is your voltage regulator. If that goes, the whole computer catches fire.
It's cooled by your CPU fan.
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Thanks, that gets the overall picture.
So, the idea is that they'll get some very nice inductors on die, capable of replacing some much more expensive external ones. Also, they can distribute the load to a lot of paralel circuits, creating the right tension for each part of the chip, and reducing the loss of each circuit.
But really, at 90W, a embebing a 76% efficient (not really an exceptional result) conversor means that you'll need to dissipabe other 28W at peak power. Well, I can't say if this is worth it
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I have yet to come across a voltage regulator that doesn't run hot. Typically, it's one of the hottest components in an electrical circuit. And we're integrated this into a slab of silicon already well-known for getting so hot it can catch fire?
Gee. If only Intel had some proper engineers like you who could think of clever things like that...
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Perhaps it's vastly more efficient than a traditional voltage regulator? It is, you know, silicon fabbed by Intel. The undisputed leader in chip fabrication technology. (Seriously. They're conservatively at least 2 generations ahead of everyone else)
Maybe one generation ahead, but that's in digital chips. While things like switching regulators can be built on digital processes (it's been done before) it's generally not the optimal process. Maybe they've come up with some clever ways to build better switchers on a digital process than previously, but it's hard to believe it's better than a process designed for stuff like this.
Full presentation (Score:5, Informative)
You can find the full slide set in PDF format here [psma.com].
If I read this right, it really is a fully on-chip switching regulator, inductors and all. They already have a test chip that they used to power a ~90W Xeon E7330 for four hours while it ran Linpack. (Or a virus -- it says Linpack in the summary page.) Voltage ripple is less than 2mV. Peak efficiency per cell looks like ~76% at 8A. They claim hitting 82% would be easy, and there are "additional advancements that cannot be reported at this time" planned for the future.
The slides have bunch of other technical details about testability features, too, which is always neat to see.
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hey already have a test chip that they used to power a ~90W Xeon E7330 for four hours while it ran Linpack. (Or a virus -- it says Linpack in the summary page.)
Respectable viruses take issue with your comment that Linpack is anything like them. Viruses do useful work.
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inductors and all
Now that's impressive, and I suspect the real secret to this. Not to say the semi design is trivial, but without the on-chip inductors you wouldn't have much. They weren't clear about it, but perhaps it means getting rid of the big filter caps, and relying on smaller caps for each regulator. It also explains the fast response time with a bunch of smaller regulators.
Re:Full presentation (Score:5, Informative)
virus == power virus (Score:2)
re:
Wow, thanks for the very informative post. It makes sense that being able to deal with full thermal stress would be useful. I've had my quad-core shut down on me once at 20-30 seconds into
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Keep in mind that the Intel solution use a 30MHz to 140MHz switching frequency, compared to the 0.5MHz of the LTM4620.
From a former power supply designer - Neat! (Score:5, Interesting)
That's some amazing work. The current state of the art in CPU power supply designs hasn't changed in 15 years. 12V in, low voltage out, and the output voltage has been moving lower and lower for years, with designs below 1 V. If you figure you had a few percent of tolerance in the early years when everything ran off 2.5V and that few percent remains constant, then at 1 V you have almost no room for slop. So there are a lot of output capacitors there, both those electrolytics (you always hear people complaining about them but they're CHEAP) and ceramics. The ceramics cost a fortune and you need a lot of them to get your tolerance down - the first half microsecond of a load step is entirely the ceramic capacitor's response, not the controller or anything else. Moving part of the VR onboard allows them to reduce the parasitics significantly and they can probably tolerate a little higher tolerance as a result, but moreover they can get rid of some of those ceramics in the whole system - ultimately many of those on the motherboard.
So this is taking a lot of cake out of company mouths. Analog, Intersil, IRF, ON, who else - manufacturers of controllers, MOSFETs. Inductors, ceramic and 'lytic vendors are all going to lose out a bit here. Potentially Intel can reduce the platform cost vs. AMD as well, which is interesting. There is still an onboard VR but it will be 12 - 2.4 V, wherever they think the sweet spot is for efficiency and size. And the first real change in this industry for a long time. Cool work.
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Afaict it's not explicitly stated but it's implied by a caption on page 24 of the slides pdf that someone linked above.
No significant cost savings (Score:2)
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I am totally impressed (Score:2)
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This is a breakthrough in physics, not just in semiconductor processing.
What sort of a breakthrough in physics? Have they found a way around Maxwell's equations or something?
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Not such a big breakthrough as you'd think. As you increase the switching frequency you can decrease the value of inductor and capacitors required. Last CPU supply I built - 10 years ago! - used 100 nH inductors at 300 kHz per phase. I skimmed the PSMA article but there was mention of MHz operating speeds, not at all unheard of these days, so the components ought to be much smaller. A 10 nH inductor and some hundreds of pF of capacitance seems very feasible without stretching the bounds of silicon techn
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Nothing new about physics there. It has been known for decades that a piece of wire starts behaving like an inductor at high frequencies and parallel wires or planes behave like capacitors. Both notions have been in use for high-speed analog and RF ICs and PCBs for a long time. For capacitors, there is even a whole class called "Multi-Layer Chip Capacitor" which is basically an IC with several metallization layers connected at alternating ends.
This is simply the somewhat unexpected but logical application o
Can they move the CPU away from the die ?!? (Score:2)
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Seriously? And here I thought I was being clever. I bow to the master.
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even coming from 12V
Way too high of an voltage for these sorts of semi processes. I think it starts at 2.4V.
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I would not be surprised to see efficiency in the 95+% range even coming from 12V down to 0.9V or whatever voltage this thing runs at, so you'll be throwing an extra 6W or so into a 120W package. Not bad.
Bollocks! Since the internal VR uses the same process as the CPU itself, it can't sustain high input voltages, therefore a one-stage 12V to 0.9V conversion is just a pipe dream.
The longer pdf presentation actually shows the motherboard-level 12V to 2.2V VR, which would be still rated for the full power (85W plus margin). OTOH, it's quite impressive that the 22nm process has support for 2.2V CMOS.
As others mentioned already, Intel is just trying to solve the power distribution issue, not eliminating the main
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switching inductive loads creates ringing, which will degrade in time (through HCI) the switching transistors
What's "HCI"?
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a one-stage 12V to 0.9V conversion is just a pipe dream. The longer pdf presentation actually shows the motherboard-level 12V to 2.2V VR
Do current CPU VR's do a one-stage jump from 12V to 0.9V? If so it seems they'd have an efficiency advantage by avoiding a double conversion. 12V to 0.9V seems like a big jump for a buck converter, but perhaps there's another way.
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Yes they do. Peak efficiency is usually above 90% and these days it depends mostly on the quality of the power switches and inductors, and the switch drivers strength.
There have been computer systems (especially notebooks) that did a double conversion (Vbatt to 5V, then 5V to whatever voltage was needed, CPU, memory etc), but it did not caught on.
There is also the "hidden" double conversion scheme in which the final VRs are powered from the battery, while the charger acts as a first VR,converting the adapte
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Bollocks! Since the internal VR uses the same process as the CPU itself, it can't sustain high input voltages, therefore a one-stage 12V to 0.9V conversion is just a pipe dream.
The longer pdf presentation actually shows the motherboard-level 12V to 2.2V VR, which would be still rated for the full power (85W plus margin). OTOH, it's quite impressive that the 22nm process has support for 2.2V CMOS.
The actual FIVR don't use the same process as the CPU. It's a separete die using a 90nm process. Read the page 7 of http://www.psma.com/sites/default/files/uploads/tech-forums-nanotechnology/resources/400a-fully-integrated-silicon-voltage-regulator.pdf [psma.com] for the details.
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You should contact Intel - I bet they didn't even consider this.
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CPU chips are performance-limited by heat.
My old Pentium-4: 130W
My new i7: 75W
There's plenty of headroom to output a few more watts without having to underclock the chip.
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No it's not. (Score:2)
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I suggest the tag for this story be 'whatcouldpossiblygowrong"