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Technology Hardware Science

Experimental Transistor Breaks 600 Gigahertz 381

neutron_p writes "The goal of a terahertz transistor for high-speed computing and communications applications could now be within reach. A new type of transistor structure, invented by scientists at the University of Illinois, has broken the 600 gigahertz speed barrier. A new type of transistor - built from indium phosphide and indium gallium arsenide - is designed with a compositionally graded collector, base and emitter to reduce transit time and improve current density. With their pseudomorphic heterojunction bipolar transistor, the researchers have demonstrated a speed of 604 gigahertz - the fastest transistor operation to date."
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Experimental Transistor Breaks 600 Gigahertz

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  • by Timesprout ( 579035 ) on Monday April 11, 2005 @02:37PM (#12204187)
    And is forced to pay for their replacement as well as 100 hours community service.
    • by sentientbeing ( 688713 ) on Monday April 11, 2005 @03:42PM (#12205069)
      Terahertz transistors, indium phosphides, indium gallium arsenide, compositionally graded collectors, bases and emitters, reduced transit time and improved current density... And a pseudomorphic heterojunction bipolar transistor with speeds of 604 gigahertz.....

      At times like this I like to leave a slashdot page open on articles and walk away from my computer.

      Anybody walking past my computer looks at the screen and thinks 'JESUS! How clever is that guy?'
    • by Anonymous Coward
      Almost there...

      640GHz should be fast enough for anyone...
  • But... (Score:5, Funny)

    by sulli ( 195030 ) * on Monday April 11, 2005 @02:37PM (#12204188) Journal
    can it be overclocked?
  • huh (Score:5, Funny)

    by moonbender ( 547943 ) <moonbender AT gmail DOT com> on Monday April 11, 2005 @02:37PM (#12204196)
    their pseudomorphic heterojunction bipolar transistor

    *blank stare*

    What now? It's pronounced nu-cu-lar!
    • Re:huh (Score:5, Funny)

      by Anonymous Coward on Monday April 11, 2005 @02:45PM (#12204323)
      pseudomorphic heterojunction bipolar transistor

      [sarcasm]
      Thank GOD they got this one right! If they would have invented a pseudomorphic homojunction bipolar transistor, the right-wing would have gotten pissed.*
      [/sarcasm]

      *If you're offended by the above, bugger off.
    • By that they mean the crystalline structure of the minerals used to form the transistor are engineered to an extent, or at least different from the naturally occurring structure it would normally have.
    • Re:huh (Score:3, Funny)

      by stungod ( 137601 )
      The first thing I though of was the Illudium Q-36 Explosive Space Modulator [tultw.com]. I get the feeling that both are equally destructive to life on Earth.
  • Bipolar? (Score:5, Funny)

    by TripMaster Monkey ( 862126 ) * on Monday April 11, 2005 @02:37PM (#12204200)
    From the article:

    With their pseudomorphic heterojunction bipolar transistor, the researchers have demonstrated a speed of 604 gigahertz - the fastest transistor operation to date.


    Sure...it's fast now, but just wait until it goes into its depressive phase...
  • by isd_glory ( 787646 ) * on Monday April 11, 2005 @02:37PM (#12204204)
    Yeah, because after the first 600 GHz, the next 400 GHz are a piece of cake.
    • Well in a way, yes. What you have to understand is that this is a new kind of technology. Just like the first transistor wasn't able to do what we can do today, this one hasn't reached it's full potential yet either. It won't be easy but it's a step in the right direction.
    • You jest, but in all seriousness... It's not even a factor of two to get from 600 to 1000. At least in software engineering, speed improvements less than, say, 5x, aren't really that impressive. Does the same hold true in electrical engineering?

      I typically don't bother optimizing something unless I believe I can make it 10 times faster. That is, unless we really need every last ounce of performance (which is rarely).

      • At least in software engineering, speed improvements less than, say, 5x, aren't really that impressive. Does the same hold true in electrical engineering?

        No, because unlike software engineering electrical engineering has to do with physics. For instance, the engineering required to crank up PCI-Express from 2.5 Gb/s to 10 Gb/s basically requires a complete reengineering of the whole physical layer circuitry.

        It doesn't have to do with the semiconductors so much as the physics of the wires, which really

  • Longhorn (Score:5, Funny)

    by faqmaster ( 172770 ) <jones@tm.gmail@com> on Monday April 11, 2005 @02:38PM (#12204215) Homepage Journal
    Just in time for Longhorn!

    • Re:Longhorn (Score:3, Funny)

      by maotx ( 765127 )
      Followed by Debian's next stable release followed by Duke Nukem Forever.
      In other news, Satan is asking for more engineer's souls to design a device to fight back the record low temperatures.
    • Re:Longhorn (Score:2, Interesting)

      by FreeLinux ( 555387 )
      Spare me. Please.

      I call this the race to Google. It is a test for how long it takes for a desktop machine to actually become useable. This is usually a better measure than the ambiguous "boots in x seconds", that we often see. Here is how to perform the test.

      Take any modern linux distro you like and install it as a dual boot with Windows XP. Now time how long it takes from pressing <enter> in grub (or Lilo if you are so inclined) and when you can see the main Google page. Try this with both Linux an
  • OMG! (Score:2, Funny)

    by Zsinj ( 864251 )
    Can I find these at CompUSA?
  • by nebaz ( 453974 ) on Monday April 11, 2005 @02:39PM (#12204231)
    If we assumed that all transistors on a chip (say a P4) were this type of transistor, and could run at 600 GHz, I know there is time required for a signal to cross all of these transistors, etc., and that some chips have a billion transistors on them, how fast could the current chips run with these transistors?
    • by Anonymous Coward
      Assuming you mean the speed that will be marketed to the public, thats impossible to tell without knowing Intel, AMD, or IBM trade secrets.
      That speed is dependent on the "critical path"s of the chip's logic systems & subsystems, the switching speed of a single transistor is merely a factor in that equation.
    • by RayDude ( 798709 ) on Monday April 11, 2005 @02:44PM (#12204302)
      I suspect the power requirements for this bi-polar transistor would make it impossible to build something on the scale of a P4.

      Bipolar eats power.

      I think these transistors, if found to be manufacturable, will probably be used in communications not digital logic.

      Raydude
      • by mothz ( 788133 ) on Monday April 11, 2005 @03:00PM (#12204551)
        I think these transistors, if found to be manufacturable, will probably be used in communications not digital logic.

        Indeed. The transistors used for digital circuits (i.e., computers) are mostly MOSFETs. The chief benefit of MOS transistors is that no current goes into the gate, so power is only used when switching from one state to the other (i.e. from a 1 to a 0).

        Bipolar transistors have a base current (albeit small), so they draw power even when responding to a constant signal. However, they're faster and can output a lot more current than MOSFETs, so they do have plenty of other applications.
    • Eventually, they will be able to run much much faster. But at the time the current chips aren't made to use this kind of transistor. They'll definitly bump up speed in the long run but I'm wondering if it still won't follow Moore's law [intel.com].
    • by mlyle ( 148697 ) on Monday April 11, 2005 @02:47PM (#12204362)
      It all depends on the wiring delay and how many transistors deep a pipeline stage is.

      fMax of a pipeline stage is 1/(switching times+wiring delays) under worst case thermal conditions. The wiring delays will stay about the same unless they're also improved by the new process, which is unlikely.

      A 600GHz transistor, with really deep pipelines like the P4, and very good interconnect technology might allow 20-50GHz operation; but there are many other things to contend with (like thermals/dissipation) that can limit speed. Thermals, in turn, depend on the amount of capacitance being switched, which isn't specified here.
      • One other point: transistors on exotic processes like these are most suited for wireless and communications applications at this point; problems with power density, logic density, yields, and manufacturability have thus far kept them isolated to radio and interconnect modulation systems to date, rather than bulk logic. These problems are not necessarily insurmountable, but prevent its use in fast microprocessors for the foreseeable future.
    • Even being an EE I could not answere that as Intel probably keeps that a closely guarded secret. That said, the main delay time in an Intel and AMD chip today is not the transistors, but the propogation time due to RC (resistance capacitance) in the signal path over long distances (relative to the chip size). Given that, they _may_ be able to double the Ghz, but that is all until they solve those problems. If they had a room temerature super conductor they could put in there, it would be easier to say.
    • 600 billion GHz... right? :) (I'm obviously not an EE geek either)

      And will that CPU dissipate 1.21 jiggawatts of power?

    • It has to do with how many gate stages the processor had in each pipeline stage - if the worst case stage has 14 gate delays, then the processor would theoretically be able to run at about 600/14GHz.

      HOWEVER, there is no way the chip would actually get that close - this 604GHz oscillator is probably a single ring on a chip containing many oscillators. The average speed could easily be more in the 400-500GHz range.

      Also, these transistors are BJTs, which are useless in very large xtor count chips due to t
  • by mboos ( 700155 )
    Let's pack as many big words together as possible!

    compositionally graded collector, base and emitter
    pseudomorphic heterojunction bipolar transistor
  • Power usage? (Score:2, Insightful)

    by rsrsharma ( 769904 )

    What's the power usage on this thing? For one transistor it doesn't matter too much, but remember that todays chips have billions of transitors in them- Intel's Prescott core is rediculously power comsumpive right now. Even worse, over 100 watts of the power is lost to heat! So, what's the power and thermal design power of these things?

    • Re:Power usage? (Score:5, Insightful)

      by jridley ( 9305 ) on Monday April 11, 2005 @02:48PM (#12204366)
      Even worse, over 100 watts of the power is lost to heat!

      For all practical purposes, ALL the power is "lost" to heat. Information has SOME thermodynamic value, but it's pretty damn small.

      If you have a computer that draws 500 watts of power, you have a 499.99999(etc) watt heater.
      • Re:Power usage? (Score:2, Interesting)

        by Anonymous Coward
        Replace every room heater in the world with a (networked) computer of the same wattage, get a supercomputer running with no additional energy consumption on top of normal heating needs. The nodes of the supercomputer that are active will mostly follow the nightside of the Earth and winter hemisphere, but who cares, as long as there are enough nodes at any given time, it doesn't matter whether they are located in Alaska or Chile. *This* is the future of computing.
      • Re:Power usage? (Score:2, Informative)

        All the heat that processors these days are producing have effects other than just wasting energy.

        I work at the local computer repair shop while going to school, and right now we check every incoming system for bristling capacitors. About 25% of the time they have bad capacitors. Why? Heat from the CPU is causing them to overheat, expand, and become useless.

        If you haven't looked at your own motherboard recently, make a point to. Capacitors should have entirely flat tops. Anything else means they are on

      • Re:Power usage? (Score:3, Interesting)

        by Enigma_Man ( 756516 )
        I was under the impression that information had 0 thermodynamic value. Where'd you hear otherwise? (I'm curious to know, not flaming or doubting).

        -Jesse
    • Re:Power usage? (Score:4, Informative)

      by WaterBreath ( 812358 ) on Monday April 11, 2005 @03:06PM (#12204652)
      No microprocessor any time soon is likely to be constructed using bipolar junction transistors (BJTs) such as this one, pseudomorphic or otherwise. Microprocessors are generally constructed using metal-oxide-semiconductor field-effect transistors (MOSFETs), in a power-conserving organizational standard known as complementary metal-oxide-semiconductor (CMOS).
    • Not all transistors are used in digital logic. A transistor is modelled as a voltage controlled current amplifier. Ever heard of the transistor radio? It's obviously not a digital radio :P

      These type of transistors are good for amplifying signals and buffering signals. Basically, if the transistor couldn't operate at 600Ghz then a 600Ghz signal would simply be filtered out because the transistor would be too slow.

      To answer the power question these things won't be packed in together with millions of other
  • by lheal ( 86013 ) <lheal1999@yah[ ]com ['oo.' in gap]> on Monday April 11, 2005 @02:42PM (#12204276) Journal
    They'll be clearly the best engineering team, but will lose in the finals to the more talented squad from MIT.
  • by ncg ( 772590 ) on Monday April 11, 2005 @02:43PM (#12204291)
    More and more we here about these new HBT circuits that are faster than all get out.
    The truth is that nothing will replace CMOS anytime soon. The infrastructure is already there, and it is being optimized over and over again and has a huge work force to man it.

    I once heard someone ask Intel is they ever plan to switch to HBT for speed. Their response is, and will probably be for a while, that why would they switch technologies after investing $50 billion a year in their CMOS foundries etc.

    These advancements may never make it to the point that the average consumer will take notice of them.
    And it may be that these academic inventions will never find any market relevance.
    • by NoseBag ( 243097 ) on Monday April 11, 2005 @02:54PM (#12204466)
      IMO you are correct that Intel/Microchip/AMD aren't going to change their processes without a damned good reason. But PC parts and logic circuits aren't the only thing transistors go into.

      How about the RF modulators/demodulators in all cell-phones, the RF amps in same, the special-purpose chips, regulators, detectors, buffers, amplifiers, etc that mfgrs still crank out by the butt-load, etc?

      Personally, I'd really get off on an op-amp designed around these puppies! Imagine the gain-bandwidth product (eff-sub-Tee)!
      • I agree with you on the usefulness outside of processors, digital logic, etc... But even companies like Freescale (ex- Motorola) and ADTRAN, all doing communications, use a derivitive of CMOS. Why? Because of infrastrucutre and economics. What you can do in HBT, CCD, etc you can get similar functionality and even speed (heard of strained silicon?) from CMOS.

        But yes, there will be more indium phosphide op-amps, as there are currently on the market, aimed towards the high speed communications market.


    • why would they switch technologies after investing $50 billion a year in their CMOS foundries etc.

      Hopefully, competition.
  • Now that it's /.'ed... anyone? :(
  • Man, that was Final Jeopardy's question last night! Where was this post when I needed it?
  • Silicon is widely available for current transistors. Are indium phosphide and indium gallium arsenide just as available, or are they the doping materials.

    Will material prices be the main determining cost of chips made from these products?

    I didn't RTFA -- it was slashdotted.
    • No, they are a completely different semiconductor material which is doped with something else. I once did an internship at a semiconductor lab (IMEC [www.imec.be]) where InP devices were developed (back then: 100 or so GHz). I recall they are VERY fragile (as opposed to Si which you can really kick around). Anyway, when the smallest features on chip are getting smaller, all processing (making masks etc.) needs to be more precise too, which will increase the cost. I think this is more important than the cost of the mater
  • Zero gain bandwidth (Score:5, Interesting)

    by wowbagger ( 69688 ) on Monday April 11, 2005 @02:46PM (#12204339) Homepage Journal
    OK, I cannot RTFM right now as it is /.ed, but:

    This sounds an awful lot like they are giving the zero-gain bandwidth of the transistor - the frequency at which the transistor does NOT amplfy a signal anymore.

    So, at 599GHz the transistor will amplify a little. At 600 GHz the transistor takes as much power to drive the input as it is able to switch at the output. At 601 GHz the transistor takes more power to control than it can switch.

    Given a 600 GHz zero-gain bandwidth transistor you ARE NOT going to make a 600 GHz clockspeed processor.

    • Isn't that how warp speed works?
    • I didnt RTFA either, BUT:
      Both intel und amd have already demonstrated transistors with transition frequences (or a zero gain bandwith as you call it) of more than 2 THz (IIRC, the fastest one was 3.something THz, with a double base design).

      So i dont think this would be worth mentioning if 600GHz were the transition frequency, so i guess its an actual usable for extreme HF signal processing.
  • I remember when... (Score:2, Interesting)

    by brontus3927 ( 865730 )
    In 20 years, will you you be able to say: I remember what I was doing when I first read on slashdot about the first transistor to break teh 600GHz barrier?

    But seriously, a previous poster had a point, what's the relationship between the speed of a transitor and the speed of a proccessor? Because 600GHz is a HUGE jump over 3.4GHz. If there's a 1:1 ratio, then a proccsoor of with 600GHz transistors would have 176 tiems the proccessing power over the current breed. A Beowolf cluster in a single chip!

    • by pclminion ( 145572 ) on Monday April 11, 2005 @02:57PM (#12204509)
      But seriously, a previous poster had a point, what's the relationship between the speed of a transitor and the speed of a proccessor? Because 600GHz is a HUGE jump over 3.4GHz.

      The transistors in a 3.4 GHz chip are capable of switching faster than 3.4 GHz. The chip as a whole runs at that particular speed because heat dissipation becomes problematic at higher speeds. The individual components are there, but we haven't figured out how to put them all together yet to achieve higher speeds. A processor is MUCH more complicated than a single transistor... Don't expect to see 600 GHz chips made out of 600 GHz transistors. Once we get to 10 THz transistors, you might start thinking about 600 Ghz chips...

  • I was unaware of this barrier.
  • They clocked it in a good mood, immediately after that it was seen moving along at only 20Ghz, then 200, then 600 again......
  • Great, just what I need, a manic-depressive CPU.
  • We always seem to forget that all of our cool new toys carry an enormous environmental cost. Anyone have any idea if indium phosphide and indium gallium arsenide are better or worse for the planet than current technologies?
  • It looks like Longhorn's requirements will be fullfilled!!!
  • Scope This (Score:3, Insightful)

    by Nexboy ( 868907 ) on Monday April 11, 2005 @03:03PM (#12204605) Homepage
    I just looked on Agilent's website and they don't seem to have any 600,000 MHz oscilloscopes for sale. I wonder how they tested this thing? A string of divider flipflops, perhaps?
    • Re:Scope This (Score:5, Informative)

      by elgatozorbas ( 783538 ) on Monday April 11, 2005 @03:08PM (#12204669)
      Good question, I asked myself the same one. They did NOT use a string of divider flipflops, as they only just developed the transistor itself, and to do the division the flipflops should be made of a superior technology.

      I know special methods exist to predict the f_s from low-frequency measurements. Maybe they measure the amplification at a some 'low' frequencies (GHz range) and extrapolate the gain-bandwidth pruduct from this?

      • Re:Scope This (Score:3, Informative)

        by ShakuniMama ( 785662 )
        You're right, I just looked at the Appl. Phys. Lett. paper. They measured it to 50 GHz and curve-fitted it to get 604 GHz, assuming a 20 dB/decade drop-off. 50 GHz can be measured with a HP network analyser.
  • by MOBE2001 ( 263700 ) on Monday April 11, 2005 @03:07PM (#12204658) Homepage Journal
    the researchers have demonstrated a speed of 604 gigahertz - the fastest transistor operation to date.

    How does one measure 604 gigahertz? Just asking.
    • How does one measure 604 gigahertz? Just asking.

      I'm not entirely sure on the specifics, but rumor has it you need 1.21 gigawatts.

    • Theoretically, if you can make the transistors run at 604GHz, then you can make gates that run at that speed as well. Make a flip-flop out of the gates, and you've got a frequency halver. Now you only have to measure 302GHz. Repeat if necessary.
    • by John Miles ( 108215 ) on Monday April 11, 2005 @03:53PM (#12205183) Homepage Journal
      Spectrum analyzers could "see" up to 325 GHz directly in the early Eighties. So I'd guess that newer and better waveguide mixers are available now. A Tek 2782 or 2784 analyzer could theoretically display a harmonically-downmixed signal 1.2 THz, although I have no idea how you were supposed to acquire the signal in the first place.

      You may not be able to see a single one-picosecond pulse in the time domain, but if you fire off a bunch of them in succession, you can build a picture of the waveform with repetitive sampling techniques. Technology was available in the 1960s to perform repetitive sampling in the 20-picosecond regime, so someone like Tek or Agilent or Picosecond Pulse Labs may have a sampling gate that can do the job.

      I would recommend surfing around at PPL [picosecond.com]'s site if you're seriously interested in this stuff. There may also be some photonic tech involved in the measurement; I haven't RTFA yet.
      • Actually, if you look at the paper, they only measured up to 50 GHz and extrapolated a linear (in dB) decay of the gain, and found a zero crossing at 604 GHz. So they didn't measure anything at all at 600 GHz; they only found device behavior that indicated that there would be a response up to that frequency.
  • I think at least half the words in there had to be made up. :)
  • With their pseudomorphic heterojunction bipolar transistor, the researchers have demonstrated a speed of 604 gigahertz...

    Yeah, I have a family member who's bipolar, so I can relate.
  • can it run Doom 3?
  • It's nice to see technology marching forward. But most of us were unaware that was such a thing as a 600 Gigahertz barrier. How does this advance affect those of us who consider 6 Gighertz systems to be the state of the art? If at all.
  • by DumbSwede ( 521261 ) <slashdotbin@hotmail.com> on Monday April 11, 2005 @03:37PM (#12204997) Homepage Journal
    I hadn't seen any headlines about semiconductor speed advances in awhile, so I was prepared to be impressed by this news, however having read the article and done a little Googling, it would seem to not be so impressive.

    CPUs have stalled out at about 4ghz overall clocking, cutting edge transistors seem to be hitting a wall at about 500-600ghz.

    Now granted faster gate transitions make for faster CPUs, but multiple gate operations are necessary for each state change, add signaling and propagation delay and who knows what you can really clock the CPU at (I am not an Electrical Engineer).

    Here is a page link claiming a record 562ghz transistor switching in Oct. 2002 article [compoundse...ductor.net]

    here is another claimed record of 509ghz, Nov, 2003 article [stilyagi.org]
    Obviously at odds with the 2002 anoucment. Undoubtedly it should narrow its claim for a specific transistor type.

    Here is a U of I annoucment calming a record 382 ghz Jan. 30, 2003 article [suntimes.com]
    But expects 700ghz by early 2004 (I'm guessing they didn't make it).

    Lets assume 562ghz in 2002, so we - drum roll please --- 7.5% increase in speed in 2 ½ years!

    This is not going to keep Moore's Law humming along.

    Even stranger, here are claims of TerraHertz transistors at Intel in 2002 article [pctechguide.com]

    Ironically, while googling for transistor or gate speed will show hundreds of hits, you can't actually find the switching speed for individual gates in a P4 or AMD chip. This stuff seems to be super secret stuff, and only the overall CPU clock it published. I wouldn't be surprised if the individual gates and transistors are transitioning at several dozens of ghz if not a couple of hundred or more. While Moore's Law death claims may have been premature 10 and 20 years ago, they may not be now.

    I hope I'm wrong, I want my Holodeck Playstation 5 in 2015.

  • Yikes. (Score:3, Funny)

    by BigZaphod ( 12942 ) on Monday April 11, 2005 @03:52PM (#12205178) Homepage
    "pseudomorphic heterojunction bipolar transistor"

    Sounds like it needs to see a doctor!
  • by the pickle ( 261584 ) on Monday April 11, 2005 @04:14PM (#12205432) Homepage
    SpyMac reports Apple intends to ship a Power Mac G6 with a 600 GHz processor by Macworld San Francisco '06, thus bringing the company back into harmony with Satan.

    Oh, and just to piss off right-wing Windows users, Steve has decided to celebrate 29 years of Apple with a retro pricing scheme of $666 for "Hellspawn," as the new system has been code-named.

    An Apple representative did not deny the story, saying that "company policy is not to comment on unannounced products." Clearly, it must be true.

    p
  • Pet peeve (Score:3, Interesting)

    by JoeBuck ( 7947 ) on Monday April 11, 2005 @04:33PM (#12205633) Homepage
    Nice round numbers do not form a "barrier". The speed of sound was a barrier because aerodynamics is fundamentally different for an aircraft travelling faster than the speed of sound. Likewise, new mask-making techniques (phase correction, optical proximity correction) had to be invented to fabricate chips with feature sizes smaller than a wavelength of the light used to manufacture them, so a wavelength was a barrier.

    But there's no "barrier" at 600 GHz or any other nice round number. It's just a number, and I wish tech writers and marketeers would quit using the "barrier" word in cases like this.

  • by Benjamin Shniper ( 24107 ) on Monday April 11, 2005 @05:44PM (#12206285) Homepage
    Our hero, Milton Feng, has discoverred a plot by the evil Terahertz gang to break the Universe's barier.

    Pseudomorphic, the evil gang leader, has invented a new device to break through the barrier. "I will cause the failure of all the communication devices and computers." He cries. His sidekick, Heterojunction, says "I will collect the indium the we need to finish our ultimate machine!"
    Pseudo's girlfriend, Bipolar Transistor, has a bag full of arsenide and is on the lookout to kill anyone foolish enough to interfere.

    Milton stealthily invades the enemy base, where he overhears that the Terahertz gang will strike the bandgap in selected areas. After he finds this out, he speeds his electron flow to warn the others.

    But what he doesn't know is that while his group of heroes is made of dissimilar and equally spunky men, the Pseudomorphic has his gang thoroughly doped.

    Can our hero improve the compositional grading of the transistor components enough?

    Or will the PseudoMoprh defeat them with his awesome signal charging time?

    Find out on the next episode of "Moore's Law"!

    -Ben

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