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Breadboarding a new circuit is a key skill and an important step in many projects—especially early on, when you need to move wires around and substitute components. But that very flexibility also makes it easy to knock wires out. Eventually, if your project is a keeper, you’re going to want something with a bit more permanence. Printed circuit boards (PCBs) solve all those shortcomings. But most people don’t even consider translating a one-off project into a PCB design. For one thing, PCB fabrication has traditionally been expensive, viable only in commercial quantities. (One alternative is to do it yourself with etches and silk screens, a messy and time-consuming process.) Also, there are technical constraints involved with PCB designs that are daunting to the casual hobbyist. But it turns out that nowadays you can produce a professional PCB very inexpensively.

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.

Length-match your traces to within 100 mils. Or is it 10 mils? Or should you go down to 1 mil? Should you include the lengths of the vias? How about the lengths of resistors? Understanding the origin of length-matching requirements, coupled with some rudimentary signal integrity analysis, can help answer these questions.   Determining length requirements requires an understanding of flight time, electrical length vs. physical length, loading and signal quality. Those elements are vital in determining what the length really needs to be, as well as in determining the allowable trade-offs to meet system timing goals.

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.

When the Arduino Duemilanove microcontroller appeared in 2005, it featured a set of female pin headers exposing most of the pins of the ATmega168 for easy hacking and for connecting accessory boards known as 'Shields'. The purpose of a shield is to provide new plug-and-play functionality to the host microcontroller, such as circuit prototyping, motion control, sensor integration, network and radio communication, or gaming interfaces, without worrying too much about the hardware implementation details. Seven years after the birth of the original Arduino, new shields keep coming out and are being cataloged on http://shieldlist.org/, a testament to the versatility of the design. It is also simple to build a DIY shield when nothing out there will meet your needs or when you want to understand how the shield concept works from the ground up.

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.

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.

Icosatetraped does, in fact, mean “twenty-four legged.” I’m not sure how to inject “soft” into that word (icostatetrasquishaped?), but this robot does have 24 soft legs. Or rather, 8 legs are soft (and moving) at any one time, while the other 16 are pressurized to carry the weight of the bot. It can move at about 1 meter per minute, which isn’t especially fast, but who cares, look at all of those little legs go! Made from plastic medical tubing, particle board, a bunch of solenoids, a Mac Mini, and some 24 volt rotary vane compressors salvaged from Gulf War nerve gas detecting equipment, this is about as DIY as it gets, and it’s awesome.

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).

You just built a breadboard of your expert design. You did all the simulations needed before going to layout, and reviewed the manufacturer's suggested techniques for a good thermal design for the particular package chosen. You even did your due diligence in going through the initial thermal analysis equations on paper to be sure not to exceed IC junction temperatures with a comfortable margin. But wait, you turn on the power and the IC is pretty hot to the touch. You are uncomfortable with this (not to mention the concern of your thermal experts and reliability people). Now what do you do?

STMicroelectronics has the STM8S Discovery kit for around US$7. For that little bit of money you get an 8 bit CPU with a detachable USB programming/debugging board and 32k of flash, 2k of RAM, and 1K of EEPROM. Downloadable tools include demo C compilers from a variety of third party vendors (limited to 16k, if I'm reading the literature correctly).