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4 January 2010—Though flexible devices such as roll-up displays have been promised for several years, their commercialization has been stalled by a missing ingredient: a flexible form of flash memory. But researchers at the University of Tokyo have recently developed an organic, floating-gate nonvolatile memory that behaves like flash memory, which may solve that problem. While silicon-based flash memory is fine for the mass data storage found in cellphones, digital music players, and thumb drives, fabricating it requires high processing temperatures, thus ruling out its production on flexible substrates like plastic. Organic semiconductors, however, can be processed at temperatures well below the melting point of most plastics. What's more, "the cost of flash memory is too high to use in applications that require large arrays of memory," says Tsuyoshi Sekitani, an assistant professor in the University of Tokyo's department of electrical and electronic engineering and one of the researchers who developed the new memory. "But we can print our organic memory on flexible substrates and over large areas using inkjet printers. So costs will be low."

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.

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.

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.

Single-walled carbon nanotube (SWCNT)-based thin film transistors (TFTs) could be at the core of next-generation flexible electronics – displays, electronic circuits, sensors, memory chips, and other applications that are transitioning from rigid substrates, such as silicon and glass, to flexible substrates. What's holding back commercial applications is that industrial-type manufacturing of large scale SWCNT-based nanoelectronic devices isn't practical yet because controlling the morphology of single-walled carbon nanotubes is still causing headaches for materials engineers.

The embedded world is constantly changing. You might not have noticed, but if you take a minute to recall what a microcontroller system was like 10 years ago and compare it to today's latest microcontroller systems, you will find that PCB design, component packages, level of integration, clock speed, and memory size have all going through several generations of change. One of the hottest topics in this area is when will the last of remaining 8-bit microcontroller users start to move away from legacy architectures and move to modern 32-bit processor architectures like the ARM Cortex-M based microcontroller family. Over the last few years there has been a strong momentum of embedded developers starting the migration to 32-bit microcontrollers and, in this multi-part article, we will take a look at some of the factors accelerating this migration.

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).