ECN Blog

Embedded Power Conference Strives to Fill Power Vacuum

by Jason Lomberg, Technical Editor

From September 17-18, the Marriott Hotel in San Jose hosted the first annual Embedded Power Conference, focusing on “increasing power-management issues.” I attended this inaugural event, and it was well worth the price of admission (press get in free). Seriously though, it was a great first effort, and will fill a void in the industry.

Embedded Power was comprised of over 20 lectures, classes, and discussions. The highlight (in this humble editor’s opinion) was a panel moderated by ECN’s skipper, Alix Paultre. Entitled “Open-Source vs. Proprietary Methodologies in Digital Power Management,” the panel addressed a hot industry topic in a town hall format. Panelists included: Eric Persson from International Rectifier, Steve Oliver from Vicor, Dave Freeman of TI, Scott Herrington of Zilker Labs, and Deepak Savadatti of Primarion. Each had a unique perspective on this burgeoning industry issue. The ensuing discussion earned rave reviews from the crowd, evidenced by their passionate inquiries.

Other news from San Jose included the pairing of Zilker with Fairchild Semi, and Primarion with Infineon. Focusing on digital power products, the Zilker/Fairchild collaboration will yield point-of-load power devices, targeted at the server, networking, graphics and high-end desktop applications. In the case of Infineon, they’ve acquired 100% of Primarion, “to further strengthen its activities in the field of power management applications.” These partnerships underscored the notion that digital power has finally “arrived.”

One of the keystone sponsors, International Rectifier, also exhibited a stunning Gallium Nitride (GaN) Advance. According to their press release, IR’s GaN-based power device technology platform, “enables revolutionary advancements in power conversion solutions.” Compared to silicon-based technology platforms, this GaN platform improves application-specific figures of merit (FOM) up to a factor of ten.

Here’s hoping that the Embedded Power Conference becomes a permanent fixture in the industry.

Performance Enhancement For Residential Light Fixtures

by Jason Lomberg, Technical Editor

In a recent beer commercial, a woman asks for a low-calorie beer, and the host proceeds to spill out half the bottle, and hand it to her. In similar fashion the EPA believes that, through the use of add-ons, one can improve the innate efficiency of legacy technologies. In reference to their new Energy Star “technical amendment,” the EPA’s Lightning Program Manager, Alex Baker, told me,  “With this approach, the Program currently has nearly 12,000 qualified fixtures from more than 120 manufacturing Partners…even incandescent technologies (the latter only allowed when used with a motion sensor to minimize operating time)” (emphasis mine). Sure, juicing up allows you to hit more home runs, but in the eyes of the law, steroids amount to an unfair advantage. Is this what Mr. Baker meant when he referred to a “competitive disadvantage” for legacy systems?

Take the “Fluorescent Light Manager” from Power-Save Energy. The device purportedly controls all Compact Fluorescent Lights (non-dimmable and dimmable) and Fluorescent Linear Tubes (T12, T8, T5, circular) with non-dimmable ballasts. In other words, the Light Manager reduces the excessive radiance of fluorescents to a more acceptable (not to mention cost-effective) level. This is no slight against Power-Save. I’m sure their device performs as advertised. But as an energy solution, this can only serve to prolong the lifecycle of an inefficient technology. There’s nothing technically wrong with the Fluorescent Light Manager. But when a performance-enhancing device, such as the Light Manager, is used by bureaucrats to “juice up” outdated systems, something is very wrong.

Biomechanical Energy Harvester Converts Human Motion Into Electricity

 by Jason Lomberg, Technical Editor

The inherent weakness of any portable device is its isolation from a constant power source, such as electricity. Thus, battery technology has evolved alongside the iPod and laptop computer. But batteries themselves are inefficient, because they either deplete themselves, or in the case of rechargeables, require electricity supplied from a power grid. But what if you could harness the energy produced by the natural motion of the human body? Bionic Power is endeavoring to accomplish that with its “Biomechanical Energy Harvester.”

The concept of biomechanical energy is nothing new. The idea dates back to bicycle generators, which have existed for over a century. It’s the most fundamental of notions to turn the normally wasted electrical output of the human body into useable energy. Bionic Power is attempting to streamline this old concept into something small, lightweight, and efficient. They discovered that the most productive energy-harvesting site for walking is the knee joint. Thus, the Biomechanical Energy Harvester resembles a knee brace in appearance. It takes advantage of the leg’s “negative” motion, or the "braking" phase of the leg's swing. According to Arthur Kuo, an associate professor of mechanical engineering at U-M, “The wearable mechanism works much like regenerative braking charges a battery in some hybrid vehicles.”

Depending on terrain, speed, and intensity of motion, the human body generates anywhere from 3-7 w per step. The Energy Harvester is capable of receiving up to 7 w, which is then stored in a battery. The user would attach his own battery, depending on the voltage requirements. When you consider the device’s practicality, you need to analyze its specs. The device weighs about three pounds (no small number for the knee joint), and a battery would increase that amount. The Energy Harvester is being marketed heavily for military application, but its design may prohibit its practical usage. Three pounds alone won’t break the back of your average soldier (especially if it could eliminate heavier, bulkier electrical devices), but its knee-brace design is problematic. Soldiers wear knee pads into the field for obvious reasons. The extra weight, even three pounds, could put tremendous strain on their kneecaps.

At present, Bionic Power is trying to produce a prototype that meets mil-specs. They’re trying to make it lighter still and more efficient. Ultimately, the Energy Harvester may find a niche market- the have-it-all electronic gizmo crowd. Fitness buffs may find the additional weight beneficial, and public figures may wish to be seen with it. But it’s doubtful that Bionic Power will sell its idea to the military, a lucrative client for electronics manufacturers.