Power Hotspot

The PAE50 and PAE100 20- and 30-A eighth-brick dc-dc converters feature 1.8-, 2.5-, 3.3-, and 5-V outputs. They comply with the Restriction of Hazardous Substances (RoHS) directive. Also, they're CE-marked and safety-approved to UL60950, CSA60950, and EN60950 specifications. The 3.3- and 5-V models are capable of efficiencies of as high as 90%. Features include overcurrent and overvoltage protection, remote sensing, output adjustment trim, and remote on/off capability. Prices for start at...

The EClampTM3343C protection and termination device works with both upstream and downstream USB 2.0 and on-the-go (OTG) ports in portable electronics and peripherals. It protects USB ports from electrostatic discharge (ESD), filters electromagnetic interference (EMI), and incorporates terminating 1.5-k(omega) pull-up and pull-down resistors that enable it to identify the type of port it is supporting. It also integrates a 33-(omega) series termination resistor for impedance matching. Pricing...

The LTC3453 synchronous buck-boost dc-dc converter targets lithium-ion (Li-ion) battery-powered applications where it can drive white LEDs with up to 500 mA. It operates automatically in either a synchronous buck, synchronous boost, or buck-boost mode, depending on input voltage and LED maximum forward voltage. This is of particular importance in high-current LED applications because the LED forward voltage can vary from 2.7 to 4.9 V depending on current levels and LED tolerances. The...

The PSA series of encapsulated, PC board-mount switching ac-dc supplies suits ruggedized industrial applications such as portable equipment, CRT terminals, automation, and transportation equipment. These supplies handle inputs from 90 to 260 V ac and output single, dual, or triple outputs of 3.3, 5, 12, 15, or 24 V dc. Different models deliver 5, 10, 15, or 30 W at efficiencies up to 84%. All models come in a UL-approved fiberglass housing, pc-board mount style. Dimensions range from 1 by 2...

Today's convergent devices--handhelds and smartphones--are surprisingly complex. They consist of one or more RF power amplifiers (PAs) and receivers, a digital baseband processor and microprocessor host, electronic memory, a high-resolution image sensor, at least one high-quality display, various lighting functions (white backlighting, camera flash, and even color fashion lighting), a lithium-ion battery, and a power-management system with integral battery-charging. In the last year, the...

Low-cost, high-current (up to 18 A) applications, such as the alarm, security, lighting, and HVAC fields, can take advantage of the CUF and CUM UL94V0 molded pc-board terminal blocks. They're approved for UL and European standards. The plug's wiring connection uses the rising-edge clamp design and is rated for 12 to 24 AWG. With its innovative header and plug design, the plug can be inserted into the same pc-board header in either the vertical or horizontal position, depending on the...

By running their dual buck-converter pulse-width modulators (PWMs) 180° out of phase, the ISL6441 and ISL6443 high-performance, triple-output controllers from Intersil reduce input-current ripple. This in turn reduces noise induced by the power supply and allows designers to use smaller input capacitors. Dual PWMs typically operate in-phase and turn on both upper FETs at the same time. The input capacitor then has to support the instantaneous current requirements of...

A complementary family of PMBus-compliant digital power-control ICs for telecom and datacentric applications supports designs from the ac line to the point of load. Texas Instruments' Fusion Digital Power family comprises three product series. Two work together in a purely digital-control mode. The third can be used with more modest digital controllers, providing most of the benefits of digital power control while closing the control loop in the analog domain. The UCD9xxx...

What is an FPGA? A field-programmable gate array (FPGA) is an IC that can include thousands of identical, programmable logic cells. A matrix of wires and programmable switches interconnects individual logic cells. A typical design involves specifying the simple logic function for each cell and selectively closing the switches in the interconnect matrix. FPGAs are primarily used to prototype an IC-based system. When the design is finalized, designers can convert the logic...

Sometimes a lot of power is just right. Sometimes 200 hp in a car is a lot better than 100. Sometimes even 1 hp gets a bicycle up the hill quite fast. Yet a bicycle can cruise along at 6 or 8 mph with less than 0.1 hp. That's part of the elegance of the bicycle, as an extremely efficient mode of transportation. Yet by using external sources of power, I can go uphill much faster than I can by pedaling my bike. The dollars per mile can drop way down, if I count my time...

An Electronic Power Bar Ultracapacitors, from postage-stamp-size units of a few Farads to multithousand-Farad cylinders the size of a large soda bottle, achieved affordable price points only a few years ago. Since then, they've been penetrating a range of markets in applications where batteries aren't enough. They're used wherever a quick burst of energy is needed. They also store surplus energy. Ultracaps on Circuit...

Almost as soon as the IEEE 802.3af Power-over-Ethernet standard was released, users started clamoring for more power. Thirteen watts is adequate for basic IP phones, but motorized cameras, multiradio access points, and devices with large color screens are seriously constrained. The fact that (under ideal conditions) typical CAT-5 cabling tolerates much higher current levels than the standard allows has led adventurous manufacturers to develop ad-hoc techniques to deliver extra power...

Digital signal controllers (DSCs) are making a splash in more than one area. They're available from a number of vendors, including Analog Devices, Microchip, and Texas Instruments. They look like a mix between a digital signal processor (DSP) and a RISC processor, plus a host of microcontroller peripherals. DSCs are a hit in motor control, soft modems, multimedia support, power-supply control, and other applications. This covers a lot of ground, but embedded developers...

Higher limits on Power over Ethernet (PoE) are coming closer. The IEEE PoE Plus Study Group has met twice since it was formed last November to develop ways to increase the maximum power that can be transmitted via IEEE 802.3af PoE from power-source equipment (PSE) to powered devices (PDs). Currently, 802.3.af limits that to approximately 13 W at the PD. The group set a number of objectives at its first plenary session in January. It determined that the PoE Plus target...

The future of power supplies was one of the hot topics at the Applied Power Electronics Conference, March 6-10 in Austin, Texas. One rap session and two professional education seminars tackled the subject. While nobody offered a clear picture of what this future would be like, though, some reasonable conclusions could be drawn. For years, power supplies have been designed using analog circuit design techniques. "Digital" power supplies have been designed over the last...

It's an axiom as consistent as the ocean tides—as technology progresses, demand for power rises. Fortunately, two companies are looking at those tides to provide that power. Specifically, they're converting the mechanical energy of waves into electricity. The PowerBuoy from Ocean Power Technologies is at work off the coasts of Hawaii, New Jersey, and Spain. Measuring 5 m in diameter and 15 m long, it's submerged a meter below the ocean's surface. As it rises and falls...

No longer do you need to fuss with looking for formulas when you're in the middle of a project and your hands are full. Instead, take a look at your wrist. TechNote Time Watch Co. offers a series of timepieces that feature key equations based on Ohm's Law. These watches and clocks come with sets of formulas printed on their faces. Two formula sets are available: one style for alternating current, and another for direct current. TechNote Time Watch recommends the ac style...

Over the last few years, the voltages in typical equipment cards have dropped dramatically—in many cases down to 1 V or lower—while the total card power continues to soar. An increase in different rail voltages also has added complexity to the power system in the form of sequencing and tracking between rails. Meanwhile, expectations for reliability and availability are rising due to the ongoing drive to reduce equipment downtime. There are several ways to meet the...

Fuel cells and power generators are the newest and hottest applications for microelectromechanical-systems (MEMS) technology. Their aim is to run future portable electronic devices like CD players, digital cameras, and PDAs. The point was driven home at last month's IEEE 2005 Conference in Miami Beach, Fla., where power developments stood out among the more than 200 technical presentations. MEMS continues its progress on all fronts, refusing to rest on its steady stream...

Transferring Heat: Heat elimination is a primary concern for optimizing system reliability. In electronic systems, this can involve one or more heat-transfer modes: Conduction: With conduction, hot atoms at the hot side of a solid material move around more than atoms on the cold side. This chain reaction proceeds across the solid and eventually establishes a smooth hot-to-cold temperature variation. Convection: Convection...