Group items tagged

In separate keynote addresses in Silicon Valley, two Internet pioneers gave different takes on the future of the network of networks Monday (May 24). Vint Cerf, co-developer of the Net's TCP/IP protocol, shared his thoughts with developers of the smart electric grid, seen as a massive embedded extension to the Internet. Larry Roberts, who helped launch the forerunner of the Internet, explained his ideas for remedying the growing congestion that plagues the Web today. Smart grid developers can learn from the lessons of the Internet, Cerf told attendees at Connectivity Week here. They should follow the model of the Net in creating a layered architecture with plenty of room for flexibility in areas that cannot be anticipated today, he said in a keynote at Connectivity Week.

By using a simple value process it is possible to speed up the analysis and help identify the best approach to take when developing a constant current regulation scheme for automotive interior LED lighting systems. Various approaches exist to address this particular design challenge that may result in a slowdown of the design process while engineering analysis can be performed to consider the advantages and disadvantages of the different options.

Given the maturity of MOSFETs, selecting one for your next design may seem deceptively simple. Engineers are familiar with the figures of merit on a MOSFET data sheet. Selecting a MOSFET requires the engineer to use their expertise in scrutinizing different specifications for individual applications. In an application such as a load switch in a server power supply, the switching aspects of a MOSFET matter little because the MOSFET is on almost 100% of the time. The on resistance (RDS(ON)) may be the key figure of merit in such an application. Still other applications, including switching power supplies, use MOSFETs as active switches, and cause the engineer to value other MOSFET performance parameters. Let us consider some applications and their prioritization of MOSFET specifications.

Carnegie Mellon has taught its robotic snake to climb trees, though one hopes it won’t start offering your spouse apples. “Uncle Sam” (presumably named for its red, white, and blue markings) is a snake robot built from modular pieces. The latest in a line of ‘modsnakes’ from Carnegie Mellon’s Biorobotics Lab, Uncle Sam can move in a variety of different ways including rolling, wiggling, and side-winding. It can also wrap itself around a pole and climb vertically, which comes in handy when scaling a tree. You have to watch this thing in action. There is something incredibly life-like, and eerie, about the way it scales the tree outdoors and then looks around with its camera ‘eye’. Projects like Uncle Sam show how life-mimicking machines could revolutionize robotics in the near future.

In many instances, the way embedded software is structured and how it interacts with the hardware in a system can have a profound effect on the transient immunity performance of a system. It can be impractical and costly to completely eliminate transients at the hardware level, so the system and software designers should plan for the occasional erroneous signal or power glitch that could cause the software to perform erratically. Erratic actions on the part of the software can be classified into two different categories:

Ever since graphene was first produced in a lab at the University of Manchester in 2004, researchers around the world have been fascinated with its potential in electronics applications. Graphene possessed all the benefits of carbon nanotubes (CNTs), namely its charged-carrier mobility, but it didn’t have any of the down sides, such as CNTs’ need for different processing techniques than silicon and the intrinsic difficulty of creating interconnects for CNTs. But all was not easy for applying graphene to electronics applications. One of the fundamental problems for graphene was its lack of a band gap, which left it with a very low on-off ratio measured at about 10 as compared to in the 100s for silicon. Now this fundamental hurdle has been overcome. Based on research led by Phaedon Avouris at IBM’s IBM T.J. Watson Research Center, Yorktown Heights, New York, IBM is reporting that they have created a significant band gap in graphene.

The potential for the QTC material to transition from an insulator to a conductor (i.e. change its electrical property) is influenced by how much deformation the material is experiencing as a result of the applied mechanical pressure. QTC can be used to produce low profile, low cost, pressure activated switches or sensors that display variable resistance with applied force and return to a quiescent state when the force is removed. The difference between a QTC switch and a QTC sensor is arguably only the speed and amount of physical input required to achieve the required switching point or resistance range.

Anyone can bake a cake, but while some chefs bake dry, uninspired bricks of dough, there are other chefs who make cakes we would die for. The ingredients may be the same, but the outcomes are so very different. This is also the case between average electronic products and world-class, market-changing products. One of the most recent technical sensations is the capacitive touch screen. But what makes some touch screen-based products amazing, while others get such poor reviews?