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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.

This article features an example chapter from a new *Hot-off-the-Press* book on FPGA Design that just recently hit the streets in August 2010. This chapter is reproduced here with the kind permission of the publisher – Springer. This book -- FPGA Design: Best Practices for Team-Based Design -- describes best practices for successful FPGA design. It is the result of the author’s meetings with hundreds of customers on the challenges facing each of their FPGA design teams. By gaining an understanding into their design environments, processes, what works and what does not work, key areas of concern in implementing system designs have been identified and a recommended design methodology to overcome these challenges has been developed.

Events such as natural disasters, military actions, and public safety threats have led to an increased need for robust robots — especially ones that can travel across complex terrain in any dimension. The ability to scale vertical building surfaces or other structures offers unique capabilities in military applications such as urban reconnaissance, sensor deployment, and setting up urban network nodes. SRI's novel clamping technology, called compliant electroadhesion, has enabled the first application of this technology to wall-climbing robots that can help with these situations.  As the name implies, electroadhesion is an electrically controllable adhesion technology. It involves inducing electrostatic charges on a wall substrate using a power supply connected to compliant pads situated on the moving robot. SRI has demonstrated robust clamping to common building materials including glass, wood, metal, concrete, etc. with clamping pressures in the range of 0.5 to 1.5 N per square cm of clamp (0.8 to 2.3 pounds per square inch). The technology works on conductive and non-conductive substrates, smooth or rough materials, and through dust and debris. Unlike conventional adhesives or dry adhesives, the electroadhesion can be modulated or turned off for mobility or cleaning. The technology uses a very small amount of power (on the order of 20 microwatts/Newton weight held) and shows the ability to repeatably clamp to wall substrates that are heavily covered in dust or other debris.

Scientists have great expectations that nanotechnologies will bring them closer to the goal of creating computer systems that can simulate and emulate the brain's abilities for sensation, perception, action, interaction and cognition while rivaling its low power consumption and compact size. DARPA for instance, the U.S. military's research outfit known for projects that are pushing the envelope on what is technologically possible, has a program called SyNAPSE that is trying to develop electronic neuromorphic machine technology that scales to biological levels. Started in late 2008 and funded with $4.9 million, the goal of the initial phase of the SyNAPSE project is to "develop nanometer scale electronic synaptic components capable of adapting the connection strength between two neurons in a manner analogous to that seen in biological systems, as well as, simulate the utility of these synaptic components in core microcircuits that support the overall system architecture."

In then the past few years we have seen multiprocessing systems become more mainstream, in fact most modern personal computer CPUs now feature symmetric multiprocessing systems (SMP), where multiple instantiations of the same processor share the processing burden of the applications running on the PC. While SMPs are quite common today, we typically have not seen a shift towards multiprocessing in embedded computing. However, a new type of embedded design technique gives engineers the freedom to intelligently distribute processing functions across a digital subsystem. This article will look at an example of the distributed processing technique using Cypress Semiconductor's PSoC 3 and PSoC 5 architectures, which consist of a main CPU (in this case an 8051 or ARM Cortex M3), a DMA engine, and array of Universal Digital Blocks (UDB).

In what comes as a bit of a surprise, Fuji Soft Inc.’s new humanoid robot platform for hobbyists and researchers has been given the name PALRO (pal + robot).  Naturally we feel this name is a superb choice!  Sales to research institutions will begin on March 15th, 2010 with a general release following later in the year.  The robot combines Fuji Soft’s software prowess with an open architecture which will give developers plenty of room to experiment. PALRO stands 39.8cm (15″) tall and weighs 1.9kg (3.5 lbs), and here’s the good news: it costs 298,000 JPY ($3300 USD).  Considering PALRO has 20 DOF, a camera, 4 directional microphones, a speaker, LED arrays in its head and chest, 4 pressure sensors in each foot, 3-axis gyro sensor, an accelerometer, and an Intel Atom 1.6GHz CPU, it is priced very competitively.  A comparative robot kit like Vstone’s Robovie-PC for example, costs $1100 USD more and doesn’t have such a fancy exoskeleton.

A product can be of low quality for several reasons, such as it was shoddily manufactured, its components were improperly designed, its architecture was poorly conceived, and the product's requirements were poorly understood. Quality must be designed in. You can't test out enough bugs to deliver a high-quality product. The quality assurance (QA) process is vital for the delivery of a satisfactory system. In this last part in this series, we will concentrate on portions of the methodology particularly aimed at improving the quality of the resulting system. The software testing techniques described earlier in this series constitute one component of quality assurance, but the pursuit of quality extends throughout the design flow. For example, settling on the proper requirements and specification cannot be overlooked as an important determinant of quality. If the system is too difficult to design, it will probably be difficult to keep it working properly.

Three-dimensional microchip designs are making their way to market to help pack more transistors on a chip as traditional scaling slows down. By stacking logic chips on top of one another other or combining logic chips with memory or RF with logic, chipmakers hope to sidestep Moore's Law, increasing the functionality of smartphones and other gadgets not by shrinking a chip's transistors but the distance between them. "There's a big demand for smaller packages in the consumer market, especially for the footprint of a mobile phone, or for improving the memory bandwidth of your GPU," says Pol Marchal, a principal scientist of 3-D integration at European microelectronics R&D center Imec. On 9 February, at the IEEE International Solid-State Circuits Conference (ISSCC), in San Francisco, Imec engineers presented some key design challenges facing 3-D chips made by stacking layers of silicon circuits using vertical copper interconnects called through-silicon vias (TSVs). These design constraints will have to be dealt with before TSVs can be widely used in advanced microchip architectures, Marchal says.

In 2008 a team of physicists from Argonne National Laboratory, in Illinois, and other institutions stumbled upon an odd phenomenon. They called it superinsulation, because in many ways it was the opposite of superconductivity. Now they’ve worked out the theory behind it, potentially opening the doors to better batteries, supersensitive sensors, and strange new circuits. Superconductors lose all resistance once they fall below a certain temperature. In superinsulators, on the other hand, the resistance to the flow of electricity becomes infinite at very low temperatures, preventing any flow of electric current.

It’s 2020, and it’s sunny outside. In fact, it’s so bright in your kitchen that you have to squint to see your grapefruit. You flip on your e-reader and the most recent e-issue of IEEE Spectrum pops up on-screen, the colors and text sharp and brilliant in the sunlight. There’s e-mail to answer, but you want to make the early commuter bus, so you roll up your e-reader and stuff it in your jacket pocket.

When considering the resolution required for an A/D converter (ADC) integrated in a microcontroller (MCU), embedded systems designers must balance cost and performance. Higher ADC resolution implies higher-cost MCUs, but in some cases you can use other features in the MCU to enhance the ADC performance via software. That approach lets you achieve higher resolution using an inexpensive integrated ADC. Here's how to use of oversampling to achieve extra bits of resolution for an ADC integrated in an MCU.

Predicting trends is difficult even by the most connected industry experts, but one trend that's easy to spot is the widespread acceptance of multicore SoC. This is happening for a number of reasons. First, it's been years since the workstation first adopted the multicore processor architecture to solve such issues as increasing performance and power concerns. While the adoption rate in workstations is now saturated and is fully supported by General Purpose OSs (GPOS), the embedded world is just now looking at ways to adopt multicore architecture. Second, several SoC vendors have been providing multicore solutions including Cavium, Freescale, MIPS, and ARM; but up until now, these solutions have been limited to networking and used for performance enhancements rather than for low power. The rest of the embedded industry has had limited hardware options available as low-power design is a driving factor. While the ARM 11 MPCore was ahead of its time, the Cortex-A9 MPCore design is ready for primetime and is gaining acceptance in the embedded marketplace. As a result, SoC vendors have adopted the Cortex-A9 MPCore hardware as a basis for their next generation designs. Over a year ago, Texas Instruments pre-announced their next-generation OMAP designs in the OMAP 4 with a dual-core Cortex-A9 MPCore, scheduled for production in the second-half of 2010. ST Microsystems has pre-announced their next generation consumer devices which will be based on the Cortex A9 MPCore.

Rosie, the robot who kept house for the title family in "The Jetsons," a 1960s animated television show, has at last come alive—sort of. Before you'll see a robot slicing cucumbers in your kitchen, researchers will need to make these mechanical servants smarter. Here's how three teams are tackling this challenge.

Tiny semiconductor dots could lead to a new type of circuit based on magnetism rather than current flow. At least that’s the hope of researchers who’ve made the dots and are hoping to build them into a workable device. ”We want to make it into a so-called nonvolatile transistor,” says Kang Wang, head of the Device Research Laboratory at the University of California, Los Angeles. Such a ”spintronic” transistor would retain its logic state in the absence of current and require less power to switch a bit, reducing the electrical power required by a computer chip by as much as 99 percent. Wang’s research, supported in part by Intel, was published in March in the online version of Nature Materials. Where electronic transistors rely on the presence or absence of current to register the ones and zeros of digital logic, spintronic transistors depend on ”spin,” a quantum characteristic of the electron. Picture the electron as a rotating globe. When the north pole is pointing upward, that’s spin up; when pointing the other way, it’s spin down. When the spins of most electrons are aligned, the material is magnetic. When their spins are random, the material isn’t. An applied current can align or randomize the spins, allowing for spin-based switches.

A new form of propulsion that could allow microrobots to explore human bodies has been discovered. The technique would be used to power robots and other devices such as microfluidic pumps from a distance. Finding a propulsion mechanism that works on the microscopic scale is one of the key challenges for developing microrobots. Another is to find a way to supply such a device with energy because there is so little room to carry on-board fuel or batteries. Now a team lead by Orlin Velev at North Carolina State University in Raleigh, US, has found that a simple electronic diode could overcome both these problems. Velev and Vesselin Paunov from the University of Hull, UK, floated a diode in a tank of salt water and zapped the set-up with an alternating electric field.

A new form of propulsion that could allow microrobots to explore human bodies has been discovered. The technique would be used to power robots and other devices such as microfluidic pumps from a distance. Finding a propulsion mechanism that works on the microscopic scale is one of the key challenges for developing microrobots. Another is to find a way to supply such a device with energy because there is so little room to carry on-board fuel or batteries. Now a team lead by Orlin Velev at North Carolina State University in Raleigh, US, has found that a simple electronic diode could overcome both these problems. Velev and Vesselin Paunov from the University of Hull, UK, floated a diode in a tank of salt water and zapped the set-up with an alternating electric field.