Multi-Core Voltage Regulators To Increase Processor Efficiency 64
cylonlover writes "For decades, chipmakers strove to develop the fastest and most powerful chips possible and damn the amount of electricity needed to power them, but these days raw grunt isn't the only consideration. As more and more devices go mobile and these devices become more and more powerful, chipmakers must also take the energy efficiency into account. Harvard graduate student Wonyoung Kim has developed and demonstrated an on-chip, multi-core voltage regulator (MCVR) that he says could allow the creation of 'smarter' smartphones, slimmer laptops and more energy efficient data centers by more closely matching the power supply to the demand of the chip."
Intel showed the same thing 6 years ago (Score:5, Interesting)
Including the same charts and graphs.
http://www.anandtech.com/show/1770 [anandtech.com]
How this guy is going to get a patent on this stuff based upon his work in 2008 when Intel showed it onstage at IDF in 2005 is beyond me.
Distribution (Score:4, Interesting)
So this is a way for an ALU (say) to send a message to to the MCVR saying "we need ten trillion electrons" when it is asked to a floating point multiplication, then the electrons get parcelled out and the ALU shuts down when the job is done. Sounds reasonable but there is still going to be a voltage regulator off the chip. This is more like an intelligent distribution system.
SmartReflex? (Score:4, Interesting)
Sounds similar to SmartReflex (tm) which is shipping on millions of phones.
http://focus.ti.com/general/docs/wtbu/wtbugencontent.tsp?templateId=6123&navigationId=12032&contentId=4609&DCMP=WTBU&HQS=ProductBulletin+PR+smartreflex [ti.com]
Where it differs is that there is an on-chip regulator to do the dynamic scaling.
The TI solution has a couple of regulators on-chip, with a couple of output voltages, as well as a more variable external solution.
The above device has variable regulators on-chip. (for annoying technical reasons, these are linear regulators, not switching,
so if they regulate to 50% output - half the (reduced amount of power needed) is wasted as heat.
These are not "voltage regulators" (Score:2, Interesting)
Lotsa fuzzyness in this blurb. Let's see if we can help clarify:
(1) First, these are not "voltage regulators". in the usual sense of something that takes an unregulated voltage and provides a stable, regulated voltage. They're the opposite-- taking a relatively stable main battery bus and dropping it down to various lower and possibly varying voltages. The goal being to sacrifice some speed and noise margin in order to use less power.
(2) Next: putting voltage droppers on-chip inevitably leads to much lower efficiency-- the only way to efficiently drop voltage is to use a switching-mode regulator, which not only generates a lot of electrical noise, it requires a big hefty inductor and capacitor, neither of which can be made on-chip. This on-chip voltage-dropping scheme cannot be any more efficient that using a plain old resistor, where you end up wasting a lot of power to get to a lower voltage.
(3) Dropping the voltage is not the only way to save power. In a pure CMOS chip you can scale down the clock speed and the power usage goes down by the same factor. This is a whole lot simpler, reliable, and more power efficient than dropping the voltage.