Gate and metal delays will both be important for this processor, but I would guess that the total delay between registers would still be dominated by gate delays (about 70-80%). You are right that drift velocity has a linear correlation with dopant concentration. However, this linearity ends when the doping level is too high or the electric field is too strong; such a situation is called "velocity saturation" and occurs at about 10^7cm/s. Otherwise, you could just increase your doping level (or voltage) and get an infinitely fast transistor!
That was an interesting point you brought up about how charge carriers vary with temperature. As long as the temperature remains above a certain point, there is enough thermal energy for ALL the electrons/holes to leave their parent atoms. I know that for Arsenic this number is -173C but I don't know any others. Liquid nitrogen has a boiling point of about -200C, but I doubt the transistors would actually get so cold that the carriers stop moving completely. Anyhow, if that happened, then we wouldn't be reading this news story on/.
Mobility does decrease with temperature; the explanation that I have been taught is that lattice vibrations prevent the charge carriers from moving freely as the temperature goes up. It is possible that the velocity saturation limit goes up when the chip is so cold, but that is more of a physics issue than an electronics one so I don't know. The intuition could be that the lattice is so stable that higher currents are enabled. Alternatively, it is possible that the circuits do not nominally operate anywhere near velocity saturation and the supercooled regime accomplishes the same effect as increasing the voltage (without fear of breakdown/shoot-through) or increasing the dopant concentration (without a decrease in carrier mobility).
By the way, I forgot to mention that increasing dopant concentration has the side effect of decreasing the carrier mobility. So that is another reason why increasing the doping level beyond a certain point would not give you a faster transistor.
In other words, the speed of transmission is not constant. Hope that answered your question!
The extreme cooling they are doing is not just for removing the heat generated by the chip. As temperature decreases, the mobility of charge carriers increases, allowing for a faster circuit. In fact, if they were to run a supercooled chip at the nominal clock frequency, they would have hold time violations and the chip would not work. In other words, the data would propagate so quickly that it would corrupt the previous piece of data.
I think this is a great start for an application to help musicians. Any classical musician knows that the amount of sheet music you own quickly spirals out of control. Not only that, but the books are heavy and cumbersome for a student to drag around. And they can be very annoying when they don't lay flat or the binding breaks. Oh yeah, and these books are very expensive, especially when you need a specific edition imported from Germany.
I was impressed that some of the books on books.google.com were sheet music books, although I was only to find partial previews for the ones I care about. Still, it is a good step and hopefully publishers will move towards downloadable sheet music in the future.
Some day, I hope there will be a good, cheap, portable sheet music tablet display with enough memory to hold a library of music scores. It could have some basic musician's tools like a metronome, digital tuner and audio record/playback. It could also have a wireless connection so that a conductor could just transmit the entire orchestra's music in one button press instead of passing out and keeping track of a hundred different scores.
I don't agree with you. At my business, I use Windows and Linux for different tasks. So I will open up my in-progress spreadsheets/presentations with either MS Office or OpenOffice, update them, and save them in xls or ppt. I have not had any issues at all with incompatibility or formatting differences. Whenever I email a spreadsheet/presentation to somebody, the recipient does not even know that OpenOffice has been used at some point and will just assume I used MSO for everything.
I can't think of a more "mixed" approach, and it is working great for me.
I was studying at MIT from Sept 2001 to Jan 2006 and never saw nor heard of anything like what you describe. I think you must be thinking of another university. Whenever lecture notes or textbook material was distributed in an electronic format, they would just be in PDF format accessible with a personal web certificate.
I agree that privacy is an extremely important concern. With that said, there is tremendous potential for a "not evil" system that has so much information on users. With knowledge about my buying habits, emails, search queries, video preferences, etc.., such a system could introduce me to new products, movies, and TV shows that I don't know about but would probably enjoy. This is the concept behind the Netflix recommendation system but expanded to cover a lot more things than movies. Amazon comes to mind as also having a recommendation system, although theirs is particularly insidious.
One really cool/creepy feature is that such a system could introduce complete strangers that would be likely to become friends. Why not have GMate or GFriend for those that choose to participate? The system would certainly have a lot more information to base their matches on than whatever false image of themselves people are trying to project using conventional dating and friending sites.
While they must be very careful about privacy issues, there are a lot of good things they could do with a such an accurate picture of the users. Personally, I would love to have a tool that lets me know which TV shows are worth watching for the upcoming season based on my preferences and interests. And helping us to meet people in a similar geographical area with similar hobbies and interests would be pretty cool as well.
Technological advances sometimes seem silly when they are first introduced. But you have to remember that new devices and applications will be developed to utilize the technology. I think people will find a lot of uses for UWB, especially in syncing portable devices like cell phones and MP3 players. Maybe you don't see a need for it, but there is also a lot of potential in wireless speakers, displays, and printers. The point of UWB isn't just to clear your desk of wires. It is also to make life more convenient and unlock new applications.
I know you are probably joking, but this COULD actually be a trap.
EMI could put a unique inaudible watermark on every download and wait for the files to show up on P2P. Then, they could easily track down the person who originally leaked the file onto P2P by analyzing the watermark. Even worse, they would already have the name and address of the leaker and possibly a signed document promising not to share the downloaded files.
I would be very careful with any MP3 files downloaded from this service.
It seems like there is some confusion on what this feature can actually do. These motherboards let you connect your computer to your phone line so that you can make and receive Skype calls using any regular phone. All you have to do is plug your phone and your computer into the same phone network. You no longer have to use a headset or microphone like most people use when using Skype.
This kind of thing is very useful to people that make a lot of international calls but want the convenience of not being tethered to the computer. Making Skype calls can be annoying; in my case, it involves connecting a Bluetooth headset and loading the Skype software. Picking up the telephone is much easier, more comfortable and can be done without getting out of bed.
One great feature would be if the Skype functionality could work when the computer is powered off (but still plugged in). Before you flame me for being an idiot, let me tell you that I own an Asus motherboard that can play CDs with the power off. A very small part of the motherboard is always powered and supports some basic functionality. I don't know if the Skype stuff works with the power off and I wasn't able to find any manuals or specifications that explained this, so I would guess that the computer needs to be on.
Wow, I had no idea that the Voyager probes are powered by radioactive material. How bad would the fallout have been if there had been an explosion in Earth's atmosphere?
"Silicon spring" is misleading because it implies there are moving parts within the accelerometer that can break. In actuality, the proof mass is held perfectly still using a feedback loop to cancel the externally applied force. The magnitude of this applied force is read out as the acceleration. No calibration is ever needed thanks to the feedback loop.
Sounds like you might be interested in BitPim.
From the BitPim website:
BitPim is a program that allows you to view and manipulate data on many CDMA phones from LG, Samsung, Sanyo and other manufacturers. This includes the PhoneBook, Calendar, WallPapers, RingTones (functionality varies by phone) and the Filesystem for most Qualcomm CDMA chipset based phones.
I'm all cell phone as well and I have gotten three of these calls in the last couple days. I don't understand why because I've been registered with donotcall.gov since 2005 and I never give out my personal cell phone number. The calls just show up as Unavailable so I answer them and burn airtime. I would be angry if I was over my minutes; thankfully, the Verizon minutes used Firefox plugin helps me avoid that.
Anyone else getting these calls on cell phone or know of ways to stop them?
Are there any medium to large businesses out there using OpenOffice instead of Office? I am all for OpenOffice, but it seems unimaginable for the business world to wean its way off of Microsoft Word and Powerpoint.
I frequently use Skype as well as BroadVoice, which is a VoIP provider comparable to Vonage. The difference in call quality is very obvious to me. Skype's calls are fuzzy, take a long time to connect, and have intermittency problems. The worst part is the fuzziness. Broadvoice is much clearer and occasionally suffers from a mildly annoying echo effect. I wouldn't suggest using Skype unless you are cheap like me, because the call quality is just inadequate.
By the way, the reason I use both services is because Skype has slightly cheaper rates on certain calls.
Slashdot Mirror
Gate and metal delays will both be important for this processor, but I would guess that the total delay between registers would still be dominated by gate delays (about 70-80%). You are right that drift velocity has a linear correlation with dopant concentration. However, this linearity ends when the doping level is too high or the electric field is too strong; such a situation is called "velocity saturation" and occurs at about 10^7cm/s. Otherwise, you could just increase your doping level (or voltage) and get an infinitely fast transistor!
/.
That was an interesting point you brought up about how charge carriers vary with temperature. As long as the temperature remains above a certain point, there is enough thermal energy for ALL the electrons/holes to leave their parent atoms. I know that for Arsenic this number is -173C but I don't know any others. Liquid nitrogen has a boiling point of about -200C, but I doubt the transistors would actually get so cold that the carriers stop moving completely. Anyhow, if that happened, then we wouldn't be reading this news story on
Mobility does decrease with temperature; the explanation that I have been taught is that lattice vibrations prevent the charge carriers from moving freely as the temperature goes up. It is possible that the velocity saturation limit goes up when the chip is so cold, but that is more of a physics issue than an electronics one so I don't know. The intuition could be that the lattice is so stable that higher currents are enabled. Alternatively, it is possible that the circuits do not nominally operate anywhere near velocity saturation and the supercooled regime accomplishes the same effect as increasing the voltage (without fear of breakdown/shoot-through) or increasing the dopant concentration (without a decrease in carrier mobility).
By the way, I forgot to mention that increasing dopant concentration has the side effect of decreasing the carrier mobility. So that is another reason why increasing the doping level beyond a certain point would not give you a faster transistor.
In other words, the speed of transmission is not constant. Hope that answered your question!
The extreme cooling they are doing is not just for removing the heat generated by the chip. As temperature decreases, the mobility of charge carriers increases, allowing for a faster circuit. In fact, if they were to run a supercooled chip at the nominal clock frequency, they would have hold time violations and the chip would not work. In other words, the data would propagate so quickly that it would corrupt the previous piece of data.
I think this is a great start for an application to help musicians. Any classical musician knows that the amount of sheet music you own quickly spirals out of control. Not only that, but the books are heavy and cumbersome for a student to drag around. And they can be very annoying when they don't lay flat or the binding breaks. Oh yeah, and these books are very expensive, especially when you need a specific edition imported from Germany.
I was impressed that some of the books on books.google.com were sheet music books, although I was only to find partial previews for the ones I care about. Still, it is a good step and hopefully publishers will move towards downloadable sheet music in the future.
Some day, I hope there will be a good, cheap, portable sheet music tablet display with enough memory to hold a library of music scores. It could have some basic musician's tools like a metronome, digital tuner and audio record/playback. It could also have a wireless connection so that a conductor could just transmit the entire orchestra's music in one button press instead of passing out and keeping track of a hundred different scores.
I don't agree with you. At my business, I use Windows and Linux for different tasks. So I will open up my in-progress spreadsheets/presentations with either MS Office or OpenOffice, update them, and save them in xls or ppt. I have not had any issues at all with incompatibility or formatting differences. Whenever I email a spreadsheet/presentation to somebody, the recipient does not even know that OpenOffice has been used at some point and will just assume I used MSO for everything.
I can't think of a more "mixed" approach, and it is working great for me.
I was studying at MIT from Sept 2001 to Jan 2006 and never saw nor heard of anything like what you describe. I think you must be thinking of another university. Whenever lecture notes or textbook material was distributed in an electronic format, they would just be in PDF format accessible with a personal web certificate.
I have a blog full of favorites and some not so favorites.
I agree that privacy is an extremely important concern. With that said, there is tremendous potential for a "not evil" system that has so much information on users. With knowledge about my buying habits, emails, search queries, video preferences, etc.., such a system could introduce me to new products, movies, and TV shows that I don't know about but would probably enjoy. This is the concept behind the Netflix recommendation system but expanded to cover a lot more things than movies. Amazon comes to mind as also having a recommendation system, although theirs is particularly insidious.
One really cool/creepy feature is that such a system could introduce complete strangers that would be likely to become friends. Why not have GMate or GFriend for those that choose to participate? The system would certainly have a lot more information to base their matches on than whatever false image of themselves people are trying to project using conventional dating and friending sites.
While they must be very careful about privacy issues, there are a lot of good things they could do with a such an accurate picture of the users. Personally, I would love to have a tool that lets me know which TV shows are worth watching for the upcoming season based on my preferences and interests. And helping us to meet people in a similar geographical area with similar hobbies and interests would be pretty cool as well.
Technological advances sometimes seem silly when they are first introduced. But you have to remember that new devices and applications will be developed to utilize the technology. I think people will find a lot of uses for UWB, especially in syncing portable devices like cell phones and MP3 players. Maybe you don't see a need for it, but there is also a lot of potential in wireless speakers, displays, and printers. The point of UWB isn't just to clear your desk of wires. It is also to make life more convenient and unlock new applications.
I know you are probably joking, but this COULD actually be a trap.
EMI could put a unique inaudible watermark on every download and wait for the files to show up on P2P. Then, they could easily track down the person who originally leaked the file onto P2P by analyzing the watermark. Even worse, they would already have the name and address of the leaker and possibly a signed document promising not to share the downloaded files.
I would be very careful with any MP3 files downloaded from this service.
The algorithms behind PageRank are no secret. Why not just read about them from the source?
It seems like there is some confusion on what this feature can actually do. These motherboards let you connect your computer to your phone line so that you can make and receive Skype calls using any regular phone. All you have to do is plug your phone and your computer into the same phone network. You no longer have to use a headset or microphone like most people use when using Skype.
This kind of thing is very useful to people that make a lot of international calls but want the convenience of not being tethered to the computer. Making Skype calls can be annoying; in my case, it involves connecting a Bluetooth headset and loading the Skype software. Picking up the telephone is much easier, more comfortable and can be done without getting out of bed.
One great feature would be if the Skype functionality could work when the computer is powered off (but still plugged in). Before you flame me for being an idiot, let me tell you that I own an Asus motherboard that can play CDs with the power off. A very small part of the motherboard is always powered and supports some basic functionality. I don't know if the Skype stuff works with the power off and I wasn't able to find any manuals or specifications that explained this, so I would guess that the computer needs to be on.
I agree. It's a disgrace to us who practice true engineering to be even loosely associated with these fraudsters.
Wow, I had no idea that the Voyager probes are powered by radioactive material. How bad would the fallout have been if there had been an explosion in Earth's atmosphere?
"Silicon spring" is misleading because it implies there are moving parts within the accelerometer that can break. In actuality, the proof mass is held perfectly still using a feedback loop to cancel the externally applied force. The magnitude of this applied force is read out as the acceleration. No calibration is ever needed thanks to the feedback loop.
Don't forget the LDPC error correcting code in the 10GbE standard. Every block of 1723 data bits is encoded into 2048 coded bits.
I'm all cell phone as well and I have gotten three of these calls in the last couple days. I don't understand why because I've been registered with donotcall.gov since 2005 and I never give out my personal cell phone number. The calls just show up as Unavailable so I answer them and burn airtime. I would be angry if I was over my minutes; thankfully, the Verizon minutes used Firefox plugin helps me avoid that. Anyone else getting these calls on cell phone or know of ways to stop them?
Are there any medium to large businesses out there using OpenOffice instead of Office? I am all for OpenOffice, but it seems unimaginable for the business world to wean its way off of Microsoft Word and Powerpoint.
Don't worry. Chances are most users will ignore the address bar no matter what color it is.
Maybe a little more proofreading next time, eh? :)
I frequently use Skype as well as BroadVoice, which is a VoIP provider comparable to Vonage. The difference in call quality is very obvious to me. Skype's calls are fuzzy, take a long time to connect, and have intermittency problems. The worst part is the fuzziness. Broadvoice is much clearer and occasionally suffers from a mildly annoying echo effect. I wouldn't suggest using Skype unless you are cheap like me, because the call quality is just inadequate. By the way, the reason I use both services is because Skype has slightly cheaper rates on certain calls.