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LED luminaires require precise power and heat management because LEDs convert most of the electrical energy they receive into heat rather than light. Without adequate thermal management, this heat can degrade the LED's life span and affect color output. Also, LEDs can fail short because they are silicon devices, so they may require fail-safe backup in the form of overcurrent protection. Resettable PPTC (polymeric-positive-temperature-coefficient) circuit-protection devices have demonstrated their effectiveness in a variety of LED-lighting applications. Like traditional fuses, they limit current after they exceed specified limits. However, unlike fuses, PPTC devices can reset after the fault clears and the power cycles.

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.

The MiniZeni series from Sharp radiates high efficiency, deliver high color rendering index (CRI) values of up to 87 and boast a long service life whilst measuring only 15x12x1.6mm. The six new models of the MiniZeni series are characterised by four special features: they have compact outer dimensions and are extremely flat, economical and bright.

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.

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 consumer handheld market is growing by leaps and bounds. With more processing power and increased support for more applications, portable products are cross-pollinating with traditional computing systems even as the product life cycle has decreased considerably in this market segment. As a result, especially in this era of economic slowdown, it is imperative that new products meet the time-to-market window to gain maximum acceptance. A decrease in product life cycles requires a reduced development cycle and an increased emphasis on reusability and reprogrammability. The emerging handheld market is also seeing interesting trends in which each individual device in a family has lower volumes but there is more customization across the series of devices, effectively upping the total unit volumes. The key challenge then becomes how to develop a system that is widely reusable and also customizable. These requirements have led designers increasingly to turn to the FPGA for handheld-product development. The FPGA has become more powerful and feature-rich, while gate counts, area and frequency have increased. FPGA development and turnaround cycles are considerably shorter than those of custom ASICs, and the added advantage of reprogrammability can make the FPGA a more compelling solution for handheld embedded systems.

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.

Sony Corp. has developed a highly flexible OLED display that can be rolled around a pencil and continue to operate. The 4.1-inch diagonal isplay is 80-microns thick and offers 432 by 240 by RGB pixels resolution at 121 pixels per inch. It is an organic LED full color display driven by an organic thin-film transistor matrix.