I helped a colleague repair their machine after it was infected with a virus by connecting to the PSU VPN and downloading some tools and so my user id was marked as being afflicted with a virus. As a result, my network credentials are temporarily revoked so I have no way to access the workgroup server that has the IC Friday images for this week (MAX660). Until I get this resolved, you will have to settle for looking at a picture of my parents’ cat, Asya. No, she is not old enough to drink, the picture was staged.
A pair of OLPC XO laptops arrived at our lab today. Given the hype and drama surrounding their debut, I decided to give them a small run through to see how usable the machine was. As the box was opened, I was very surprised at the tiny size of the device. Since this was designed for children, the size seemed fairly appropriate. The trouble started when I tried to use the device. The keyboard was about 30% smaller than a laptop keyboard and was covered with a single piece of rubber. This made the key unresponsive and made it fairly hard to type quickly. Furthermore, the mouse track pad had very poor response and was a total pain to use at points. Finally, the machine seemed very underpowered and took about ten seconds to start up a terminal without anything else running.
From a positive perspective, the laptop’s user interface was fairly intuitive and well labeled. The included video capture software worked on par with a typical 1.3MP camera phone and seemed to capture video smoothly. The device had no problem associating with our wireless network, however, there was some difficulty getting it on the VPN. The number of ports is pretty good (~3USB, audio, etc) and the battery life seems to be on par with typical portable machine. The $180 price tag was a bit higher than the $100 original, however, I foresee that the price will gradually drop as components get cheaper. Eventually adding a touchscreen would not be a bad idea.
To conclude, this laptop seems to be very appropriate for young kids. The keyboard seems like it could resist liquids and debris and the device looks durable. I didn’t see if there are any parental controls available as I doubt any parent would want to let their 5 year old sit behind a computer all day long. As for adult use, it is better to spend a little bit more money and get a subcompact laptop from ASUS or a budget laptop from Dell. The size of the machine and lack of ports (ethernet, parallel, serial) make it less attractive from a hacking perspective.
According to Look Around You, an investigative scientific program appearing on the BBC’s Channel 3, a new atomic element that may revolutionize semiconductor fabrication has been successfully formulated in laboratory conditions. This element is Intelligent Calcium (see above) which may replace sodium ion implantation in the near future and thereby increase both digital and analog circuit performance.
From a design standpoint, ion implantation is one of the crucial steps in integrated circuit manufacturing as it allow the designer some freedom to set the threshold voltage for a MOSFET transistor as well as negate some of the potential problems with manufacturing. The basic idea is that by applying a positive or negative voltage at the gate terminal, we can attract either negative or positive charges (pairs of which are constantly thermally generated) to the “top” of the device respectively. If enough of these charges accumulate, we can form a conducting channel through the substrate. By implanting immobile ions in the gate oxide region, we can change the voltage at which this channel formation begins to occur and thereby the required bias for transistor operation. It is not hard to imagine that some chemical process steps may add undesired ions at the silicon-oxide interfaces in addition to dangling bonds in the oxide, so this same technique may sometimes be used to balance the parasitic ion concentration due to processing and return the device to the designed activation threshold.
Typically, the positive ion of choice is sodium. Ions are generated by electrically heated metal and are then accelerated by electromagnetic fields until the impact the target. Upon impacting the crystal lattice, the sodium looses momentum and typically does not move from its resting position unless the device is severely heated (can happen!). The sodium’s only action is to interact with the charges around it and modulate the effective threshold voltage for the device. The main downside is that the sodium ion cannot ‘decide’ when to act, so its effects are constant throughout time.
This is where the concept of intelligent calcium comes in. Unlike the ‘dumb’ sodium, the intelligent calcium’s higher atomic weight allows it higher flexibility with its charge configuration and thereby more freedom to ‘decide’ when to act as a 2+ valence ion and when to pretend to be neutrally charged. By using intelligent calcium as a positive ion throughout an integrated circuit, a calcium network is formed where each atom becomes a node and can communicate with both adjacent and far-away atoms to get a general feel for the situation and the activity of the device. It can then modulate its charge to increase (or decrease) the individual transistor thresholds as needed. From an analog perspective, the transconductance of the device goes up tremendously as well as the frequency response (due to intelligent calcium’s rapid activation). From a digital perspective, the speed of information propagation in the intelligent calcium network exceeds the mobilities of both holes and electrons, even in a strained silicon lattice. For this reason, the transistors adjust their threshold in advance of the gate voltage changes and thereby increase their switching speeds. This in turn translates to quicker gates and overall quicker devices.
The future is bright for intelligent calcium as it has many desirable properties for semiconductor fabrication. Scientists are presently pushing the bleeding edge of technology as they investigate the possibility of using the intelligent calcium network as a means to communication between transistors and a total replacement for the metal interconnects. The progress is slow, however, I have full confidence that I will one day have the opportunity to image an metal-less, intelligent calcium powered device in the weekly IC Friday column.
Design Downloaded from WPThemes.Info Copyrights for all of the original writings and ideas belong to Nick Chernyy, use them as you like but give credit where it is due.
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