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Have you ever written code that behaves correctly under a simulator only to have intermittent failures in the field? Or maybe your code no longer functions properly when you compile with a newer version of your tool chain. You review your test bench and verify 100 percent complete test coverage and that all tests have passed with no errors--yet the problem stubbornly remains. While designers understandably place great emphasis on coding and simulation, they often have only a nodding acquaintance with the internal workings of the silicon within an FPGA. As a result, incorrect logic synthesis and timing problems, rather than logic errors, are the cause of most logic failures. But writing FPGA code that creates predictable, reliable logic is simple if designers take the right steps. In FPGA design, logic synthesis and related timing closure occur during compilation. And many things, including I/O cell structure, asynchronous logic and timing constraints, can have a big impact on the compilation process, varying results with each pass through the tool chain. Let's take a closer look at ways to eliminate these variances to better and more quickly achieve timing closure.

March has seen two significant announcements from FPGA start-ups with innovative architectures: Tabula, with their time-domain-multiplexed architecture, and TierLogic, implementing their routing switches in a layer of thin-film transistors. Both approaches promise to significantly reduce the die size and cost of high-end FPGAs. But before these announcements broke, a relatively unnoticed paper at February's International Symposium on FPGAs described what may be the most radical technology of them all: FPGAs using electromechanical relays. No, this is not an early April Fool's joke, nor is it one of those "let's see if anyone will publish this one" academic exercises. The paper presented work by professors and students at the Stanford University departments of electrical engineering and computer science, and researchers at Altera Corp. The work was supported in part by DARPA funding.

Ted Marena of Lattice Semiconductor Corp., points out that designers of digital systems are familiar with implementing the 'leftovers' of their digital design by using FPGAs and CPLDs to glue together various processors, memories, and standard function components on their printed circuit board. In addition to these digital functions, FPGAs and CPLDs can also implement common analog functions using an LVDS input, a simple resistor capacitor (RC) circuit and some FPGA or CPLD digital logic elements to create an analog to digital converter (ADC).

Chemicals giant Merck KGaA (Darmstadt, Germany) and Plastic Logic GmbH (Dresden, Germany), the developer of the Que e-reader, have announced plans to develop, test and commercialize novel lisicon-type organic semiconductors from Merck in Plastic Logic's displays. The introduction and production of the materials is planned for 2011. Having shown the Que e-reader at the Consumer Electronics Show in January Plastic Logic was originally expected to ship the e-reader in April 2010 but that launch has now slipped to June, it is reported. Merck recently invested in the expansion of its Chilworth Technical Center chemicals research site in Southampton, England, by adding laboratories to intensify and accelerate display material developments based on plastic electronics.

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.

A little more than a week after long-simmering programmable logic startup Tabula Inc. emerged from stealth mode, Tier Logic Inc. stepped into the light Wednesday (March 10), offering the first details about its technology, which employs a novel processing change to build FPGA and ASIC products on a single die. Like Tabula, Tier Logic's technology depends on a three-dimensional structure. But while Tabula uses rapid reconfiguration to, in the words of that firm's executives, treat time as the third dimension, Tier Logic's approach separates user circuits and configuration circuits into 3-D stacked layers, creating what the company calls the world's first monolithic 3-D FPGA.

Field programmable gate arrays (FPGAs) present an efficient and inexpensive alternative when it comes to implementing complete embedded systems along with important peripheral functions. The reconfigurable logic circuitry of an FPGA offers tremendous flexibility. A lesser known feature is that the outputs of a digital FPGA also permit various analogue applications.

Menta SAS and LIRMM have taped out what they believe is the of worlds first MRAM-based FPGA which has patent-protected circuitry enabling compact integration of MRAM and embedded-FPGA solutions. Researchers at the Montpellier Laboratory of Informatics, Robotics and Microelectronics (LIRMM), in France, claimed in October that they had developed a FPGA circuit based on non volatile resistive memory cell.

It is no secret that field-programmable gate arrays (FPGAs) are getting bigger and more complex all the time. The fabrication process creates smaller transistors and makes more dense chips packing more digital processing per nanometer. Engineers love to see advancement because it means they can do more with modern silicon, and many times NI LabVIEW FPGA Module technology helps by abstracting the complexity to a higher level so that engineers can more smoothly take advantage of these improvements.  Unfortunately, there is one issue with FPGAs that continues to be a time sink and only gets worse with denser FPGAs: compilation time.

Based on recent technological developments, high-performance floating-point signal processing can, for the very first time, be easily achieved using FPGAs. To date, virtually all FPGA-based signal processing has been implemented using fixed-point operations. This article describes how floating-point technology in FPGAs is not only practical today, but that the processing rates of one trillion floating-point operations per second (teraFLOPS) are feasible and can be implemented on a single FPGA die.

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.

The FPGAs referenced in these articles have complex dedicated I/O circuitries that are primarily designed to support external memory interfaces. The ALTMEMPHY megafunction is designed to support the most common memory standards, such as the DDR and DDR 2 SDRAM and QDR II+/QDR II SRAM (in a burst length of 4) interfaces. The ALTMEMPHY megafunction should be used whenever possible as it is beneficial to use the IP and timing closure methodologies used with these FPGAs, which enables users not to have to create this function manually as compared with using the ALTDLL and ALTDQ_DQS solution. However, the ALTMEMPHY megafunction does not support other external memory standards such as Mobile DDR, QDR II+/QDR II SRAM (in burst length of 2) or customized DDR and DDR 2 SDRAM external memory standards. For these scenarios, use the ALTDLL and ALTDQ_DQS megafunctions to access the FPGA architecture and build a custom external memory interface.

FPGAs referenced in this article have complex dedicated I/O circuitries that are primarily designed to support EMIF. The ALTMEMPHY megafunction is designed to support the most common memory standards, such as the DDR , DDR2 SDRAM, and QDR II+/QDR II SRAM (in a burst length of 4) interfaces. Other external memory standards such as Mobile DDR, QDR II+/QDR II SRAM (in burst length of 2), or customized DDR and DDR 2 SDRAM external memory standards are not supported. Instead, the ALTDLL and ALTDQ_DQS megafunctions are used to access the FPGA architecture and build a custom EMIF.

How's this for a wedge issue on a slow news week? When Xilinx announced earlier this year that it was changing one of its foundry suppliers from UMC to TSMC for the 28-nm node, it seemed like a blow to differentiation—at least from a process technology standpoint—between Xilinx and Altera, which has been using TSMC for years. But while Xilinx chose to go with TSMC's high-performance/low power process, Altera said this week it is going with TSMC's high-performance process. Altera maintains that customers in the high end communications equipment market are much more concerned about performance than power. Luanne Schirrmeister, senior director of product marketing at Altera, put it this way: "In communications infrastructure, nothing is battery powered. Everything is plugged into a wall."

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.

Xilinx Inc. today introduced the architecture for a new Extensible Processing Platform they claim will deliver unrivaled levels of system performance, flexibility and integration to developers of a wide variety of embedded systems. The ARM Cortex-A9 MPCore processor-based platform enables system architects and embedded software developers to apply a combination of serial and parallel processing to address the challenges they face in designing today's embedded systems, which must meet ever-growing demands to perform highly complex functions. The Xilinx Extensible Processing Platform offers embedded systems designers a processor-centric design and development approach for achieving the compute and processing horsepower required to drive tasks involving high-speed access to real-time inputs, high-performance processing and complex digital signal processing - or any combination thereof - needed to meet their application-specific requirements, including lower cost and power.

National Instruments has released a vision module for the PXI platform that provides a high-performance parallel processing architecture for hardware-defined timing, control and image pre-processing. The NI 1483 Camera Link adapter module, in combination with an NI FlexRIO field-programmable gate array (FPGA) board, offers a solution for embedding vision and control algorithms directly on FPGAs which are used to process and analyse an image in real time with little to no CPU intervention. The FPGAs can be used to perform operations by pixel, line and region of interest. They can implement many image processing algorithms that are inherently parallel, including fast Fourier transforms (FFTs), thresholding and filtering.

Recent advances in the size and performance of FPGAs, coupled with advantages in time-to-market, field-reconfigurability and lower up-front costs, make FPGAs ideally suited to a wide range of commercial and defense applications [6]. In addition, FPGAs generality and reconfigurability provide important protections against the introduction of Trojan horses during semiconductor manufacturing process[8]. As a result, FPGA applications increasingly involve highly-sensitive intellectual property and trade-secrets, as well as cryptographic keys and algorithms [7].