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Today's FPGAs are doubling in capacity every 2 years and have already surpassed the 5 million equivalent ASIC gate mark. With designs of this magnitude, the need for fast flows has never been greater. At the same time, designers are seeking rapid feedback on their ASIC or FPGA designs by implementing quick prototypes or initial designs on FPGA-based boards. These prototypes or designs allow designers to start development, verification and debug of the design—in the context of system software and hardware—and also to fine tune algorithms in the design architecture. Quick and intuitive debug iterations to incorporate fixes are of great value. The ability to perform design updates that don't completely uproot all parts of the design that have already been verified is also a bonus! Whether the goal is aggressive performance or to get a working initial design or prototype on the board as quickly as possible, this paper provides information on traditional and new techniques that accelerate design and debug iterations.

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.

In traditional short-haul microwave transmission (that is, line-of-sight microwave transmissions operating in the 18 GHz and 23 GHz radio bands),RF design engineers typically are concerned with signal aspects such as fade margins, signal reflections, multipath signals, and so forth. Like an accountant seeking to balance a financial spreadsheet, an RF design engineer normally creates an RF budget table, expressed in decibels (dB), in order to establish a wireless design. Aspects like transmit power and antenna gain are registered in the assets (or plus) column, and free space attenuation, antenna alignment, and atmospheric losses are noted in the liabilities (or minus) column. The goal is to achieve a positive net signal strength adequate to support the wireless path(s) called for in the design.

Multisim 11 is the latest version of its circuit simulation software, with specialized editions for both hands-on learning and professional circuit design. The easy-to-use Multisim software delivers a graphical approach that abstracts the complexities of traditional circuit simulation, helping educators, students and engineers employ advanced circuit analysis technology. The academic edition of Multisim 11 incorporates specialized teaching features and is complemented by circuits textbooks and courseware. This integrated system helps educators engage students and reinforce circuit theory with an interactive, hands-on approach to investigating circuit behavior. Multisim 11 Professional helps engineers optimize circuit designs, minimize errors and reduce prototype iterations. When combined with the new NI Ultiboard 11 layout and routing software, Multisim provides engineers a cost-effective, end-to-end prototyping platform. Its integration with NI LabVIEW measurement software also helps engineers define custom analyses to improve design validation…

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.

With the introduction of the WEBENCH Online Design Environment in 1999, National Semiconductor made it possible for design engineers to create a reliable power supply circuit over the internet in minutes. The user specified the circuit performance and the WEBENCH Toolset delivered. Today, WEBENCH Designer creates and presents all of the possible power, lighting, or sensing circuits that meet a design requirement in seconds. This enables the user to make value based comparisons at a system and supply chain level before a design is committed. This expert analysis is not possible anywhere else.

Lattice Diamond design software offers leading-edge design and implementation tools optimized for cost sensitive, low-power Lattice FPGA architectures. Diamond is the next generation replacement for ispLEVER featuring design exploration, ease of use, improved design flow, and numerous other enhancements. The combination of new and enhanced features allows users to complete designs faster, easier, and with better results than ever before.

Verification of algorithm-intensive systems is a long, costly process. Studies show that the majority of flaws in embedded systems are introduced at the specification stage, but are not detected until late in the development process. These flaws are the dominant cause of project delays and a major contributor to engineering costs. For algorithm-intensive systems —including systems with communications, audio, video, imaging, and navigation functions— these delays and costs are exploding as system complexity increases. It doesn't have to be this way. Many designers of algorithm-intensive systems already have the tools they need to get verification under control. Engineers can use these same tools to build system models that help them find and correct problems earlier in the development process. This can not only reduce verification time, but also improves the performance of their designs. In this article, we'll explain three practical approaches to early verification that make this possible. First, let's examine why the current algorithm verification process is inefficient and error-prone. In a typical workflow, designs start with algorithm developers, who pass the design to hardware and software teams using specification documents.

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.

In earlier articles on intelligent sensor design, we saw how valuable they can be to both end users and those who manufacture and sell them. It’s now time to delve more deeply into what it takes to make intelligent sensors work.   The first step in that journey is to develop a solid, intuitive understanding of the principles of digital signal processing(DSP). Unlike many introductory DSP articles and texts, the focus here will be on presenting and using the important concepts rather than deriving them, for the simple reason that addressing the subject in depth is a book-sized, not a chapter-sized, project.

Simple mathematical analysis shows that the best answer to address this problem is to  select a CR ratio QGD/QGS1 that is less than 1. Other factors to consider for preventing C dv/dt induced turn-on include low driver-sinking impedance (<1 Ώ), a FET design with intrinsically low RG, an externally-applied G-S capacitor and Q2 packages that minimize parasitics and voltage ringing.

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: