Liquid cooling provides a convenient way to remove heat from electronic components, boards, and systems. Its efficiency exceeds that of moving air, and liquid-cooling equipment does not require air channels throughout an enclosure. Some engineers may think of liquid cooling and picture leaking pipes and damaged electronics. Fortunately, liquid cooling has moved from the prove-it-to-me stage to routine use in high-end computers and military-and-aerospace equipment. So, just think of liquid cooling as a reliable and efficient way to move heat from one place to another. The removed heat can travel some distance to a radiator that dissipates the heat into outdoor air, municipal water, seawater or even another cooling system.
On a recent flight I talked with a software-engineering manager about the challenges of finding good embedded-system developers. She told me she has a team of 12 developers, but only three had proficiency with drivers, board-support packages, and boot-loaders. The other nine -- all good application developers -- lacked low-level coding experience. I asked if she had heard of the Microsoft .NET Micro Framework.
Editor’s note: It is with great pleasure that I welcome Alix Paultre to the cast of characters at ECN. I’m handing over this bit of print real estate to Alix this month — but it’s only a one-month rental. See you next month! Cheers…Aimee Kalnoskas, editor-in-chief
Engineers and system designers can exchange information around the world using instant messaging, Web browsers, and e-mail protocols based on Ethernet. The impact on our daily jobs is part of a larger trend described in the book The World Is Flat by Thomas Friedman. Friedman describes how broad Ethernet adoption, combined with open protocols and widely adopted platforms such as the World Wide Web, causes a dramatic shift in the global economy. In his words, the global economy is becoming “flat.” In addition to delivering data in the global economy, Ethernet is well suited for distributed test and industrial automation systems. New Ethernet standards have increased bandwidth from 10 Mb/s in 1983 to 1 Gb/s in 1998. It will take several years for the new 10GBASE-T standard (2006) to reach comparable price points with the currently deployed 1GBASE-T and 100BASE-T standards. With Ethernet, as well as PCI Express and USB, industrial automation and test systems can operate with higher performance at lower costs.
Evolving communications technologies require systems that can support many existing and emerging standards. By implementing communication functions in software, designers can build such “future-proof” communications, called software defined radios (SDRs). Software tools must let developers work at a high level of abstraction so they can port reusable code to other systems. But even though SDRs depend on software for their agility, they still require hardware in the form of switch fabrics, high-speed interconnects, and heterogeneous processor architectures that include FPGAs.
The Software Defined Radio Forum is an industry association that promotes the development and deployment of reconfigurable radio systems. The group includes 100 member organizations involved with commercial, defense and civilian communications. Members' activities include wireless services, network operations, public-safety communications, and hardware and software developments.
Many different standards for wireless communications equipment are in use today. Narrowband communication standards use stronger transmission in a small slice of bandwidth. Wideband standards use lower transmission power across a larger bandwidth. Each standard defines minimum performance characteristics for receivers, and includes specifications such as bandwidth, maximum signal level, and sensitivity. GSM is one narrowband example; the channel bandwidth is 200 kHz. A GSM receiver must have a minimum sensitivity of –104 dBm and be able to tolerate a –13 dBm signal at the antenna. In contrast, CDMA2000 is a wideband standard that uses a 1.25 MHz bandwidth. CDMA2000 receivers need to have a minimum sensitivity of –117 dBm/1.25 MHz and tolerate a maximum signal of –30 dBm at 900 kHz offset.1
"Cost still rules applications," said Ross Bannatyne, Marketing Director at Silicon Laboratories, a supplier of 8051-based MCUs. "If 8-bit MCUs solve problems, why use more expensive 32-bit chips?" Newer 8051 derivatives, for example, execute 100 MIPS and on-chip multiply-accumulate accelerators let them handle signal-processing tasks. According to Bannatyne, some engineers might not realize 32-bit MCUs can incur code penalties. "They might assume an algorithm that requires 16 KB in an 8-bit MCU also needs 16 KB in a 32-bit processor. Often the code takes more memory in the 32-bit processor, often much more."
“The frog was wrong” — that’s what I saw on a giant billboard when driving toward New York’s Lincoln Tunnel last year. It turned out to be a Toyota advertisement, with fine print stating, “It is easy to be ‘green’ when you drive the new such-and-such…” I didn’t think much of the car, but the slogan is terrific. That’s what we think here at ECN.
One of the most critical factors in designing handheld, portable electronics today is reducing overall system power consumption. With increased consumer expectations, portable devices require longer battery life and higher performance. Even power reductions on the order of 10 mW are crucial to portable system designers and manufacturers.
The industry’s conversion from leaded (eutectic) to lead-free has been slow. The industry perception prior to July 2006 was a virtual overnight switch to lead-free. However, today many OEMs still have a “don’t care, wait and see attitude” since they’re either RoHS-exempt at this time or don’t sell into Europe.
As a youngster I enjoyed wiring up circuits with knife switches, lamps, buzzers and large dry cells. While in high school I made frequent trips to surplus-electronics stores in New York City and ordered components from mail-order supply houses. My projects included a 4-bit binary adder -- built from switches and relays -- and a tic-tac-toe machine. I also built my share of kits from Knight, Eico and Heath. My friend Bill Kuhn designed and built relay-logic learning machines.
When system designers must extend battery life, many believe one chip uses less power than two. The reasons seem straightforward: Chip-to-chip communications consume more power than on-chip communications, and two chips will inevitably have more transistors and thus more leakage than a single chip with equivalent functions. But power-saving design techniques often turn conventional wisdom on its head.
As the electronics industry moves to new IC-fabrication technologies, chip designers must deal with tighter power specifications and with new power constraints. In large and complex designs, implementing a reliable power network and minimizing power loss have become major challenges for design teams.
My neighbors, who live almost a hundred yards and up a hill away from me, love their SUV’s, monster trucks and electricity. During the Christmas season, the illumination from their myriad of Christmas lights and blow-up, lighted lawn Santas and Frosties alone allow me to keep my flood lights off for most of December.