PowerBeams’ infrared power transmission system, Powermitter, can be used to deliver power to a system without the need for wires. It uses IR laser diodes to transmit power at distances up to 100 m. And Longer ranges are possible.

STMicroelectronics and LG Chem have announced plans to develop an automotive battery pack that will extend the potential of electric and hybrid electric vehicles, combining LG Chem’s lithium-ion (Li-ion) battery technology with a battery-management chip from STMicroelectronics.

The TSR-1 series switching regulators from Tracopower can be used as drop-in replacements for 78XX series linear regulators. The nine models in the TSR-1 series provide 4.75- to 32-V dc input ranges and output voltages of 1.5 to 15 V dc and 1-A output current.

The LT3682 step-down switching regulator from Linear Technology provides input transient protection up to 60 V. Its Burst Mode operation keeps quiescent current under 75 µA in no-load standby conditions.

International Rectifier has two new control ICs for dimming compact and tube-type fluorescents. Most designers won’t ever see them, though, because they go into the bases of compact bulbs or into lighting fixtures. Still, they’re interesting to study as examples of energy-efficient design and for the elegant way they provide dimming, including dimming in legacy systems that use triac controls. The IRS2530D DIM8 squeezes a complete dimming...

Numerous opportunities exist for ultra-low-power (ULP) energy-harvesting technologies and related power-management ICs and energy storage. The challenge in analyzing this market boils down to the sheer number of potential applications and the requirements of each market, many of which overlap with portable applications. Any “roadmap to commercialization” has to consider not only pricing, but also the technology performance metrics that must be matched to...

When talking about energy harvesting, the discussion tends to focus on photovoltaics or piezo beams, electrothermal devices, and other ways of turning stray energy into electrons. However, other technologies also can make energy harvesting useful. Let’s look at a few: • Wireless mesh networks: These have made it possible to place low-cost radios (the jargon is “motes”) and receptive gateways into tough-to-monitor environments. Despite their low...

One cannot talk about energy harvesters without discussing wireless mesh networks, sensor batteries (particularly thinfilm batteries), and supercapacitors—along with concepts of power management—nearly in the same breath. Harvesting is a complex and evolving discipline that promises rewards and challenges for engineers who want to take existing skills in new directions. Most of the technical background information in this report was derived from interviews...

In my previous column (“Applications Drive Component Power Designs,” Sept. 11, 2008, p. 18, ED Online 19486), I contended that the application drives the selection of a specific power component—or it even forces the creation of a custom component. But, it must be admitted, there is another side of the coin. Many price-sensitive engineers see value in changing their ...

After the Roadster test drive, I had a serendipitous interview with Tesla’s CTO, J.B. Straubel, during MIT’s annual Emerging Technology conference. In the video interview, Straubel shares info about the upcoming Tesla sedan and the new factory slated to be built in San Jose.

Getting to take a test ride in a Tesla Roadster is a thrill enough, but getting Bob Pease out for a spin as well—talk about an experience! Our Analog and Power Editor Don Tuite just so happens to married to Vicky Tuite, senior test engineer at Tesla Motors. Talk about lucky. She recently had the keys to a brilliant orange Tesla with the enviable mission of running down the batteries for some low-charge tests the next day. And guess who got to ride shotgun.

A number of situations could benefit from the high efficiency of a switched power supply, save for the supply’s intrinsically high noise level. For example, an optical communications application using a large number of laser diodes could employ a switched power supply to avoid the need for heat-removal techniques. However, the laser diodes require a noiseless environment. A hasty decision to use a switcher would not be rewarding ...

While converting an older Volkswagen to electric power, we wanted to display the battery voltage on the existing fuel gauge. The gauge used an electromechanical regulator to resistively control the heating of a bi-metallic thermal strip. The regulator is periodically pulsed by the vehicle’s 12-V battery power. The conversion application provides a proportional control uniquely coded to synchronize and scale into the vehicle regulator’s proportionalcontrolled ...

An N-channel JFET has a low bias current when its gate is biased negative to the source. However, this requires either that the gate voltage be biased negative with respect to the source voltage or that source voltage be biased positive with respect to the gate voltage. For ac amplifier designs, gate biasing can be made self-biased by using an RC network at the source to hold the positive voltage for a period longer than the time period of the input pulse/frequency...

Current-mode control loops (particularly the popular 4- to 20-mA controls) are used in many industrial applications because of their immunity to induced EMI from motors, contactors, relays, and other sources. Off-the-shelf process controllers often have 4- to 20-mA (sometimes 0- to 20-mA) output options for adjusting speed, pressure, temperature, or some other parameter in a closed-loop control system. The receiving circuit needed for the 4- to 20-mA control...

Battery-operated equipment often requires a low-voltage monitor to warn the user when the battery voltage is too low or to perform other functions, such as power-source switching or device shutdown. Many specialized ICs are available to satisfy this need, but most target applications that use fairly low-voltage lithium or NiCd batteries. Thus, they’re not directly compatible with applications using lead-acid batteries, which may go as high as 14 V during...