Power Electronics

November 2003 Archives of Breaking News


Edited by PETech Staff

IEEE802.3af-Compliant Power Device Interface Controllers

Maxim Integrated Products’ new MAX5940A/MAX5940B interface controllers meet the powered device (PD) requirements of IEEE802.3af-compliant Power-over-Ethernet (LAN) systems. These ICs are ideal for power devices such as IP phones, wireless LAN access point and IP cameras. The MAX5940A/MAX5940B allow these power detectors to be safely powered over the network category-5 (CAT-5) cable.

Rated for up to +67-V operation, the MAX5940A/MAX5940B are fully compliant to the IEEE802.3af standard and are compatible with legacy power-sourcing equipment (PSE). They provide a valid 25 kΩ signature discovery and classification signature. Programmable inrush current-limit control gives these PDs the flexibility to consume more power than the maximum 13 W allocated by the IEEE802.3af standard.

During detection, both devices draw less than the 10 µA of offset current, allowing accurate detection of the 25 kΩ signature. An internal 0.6 Ω N-channel MOSFET provides isolation during detection, inrush-current control, and efficient power-mode operation.

The MAX5940A is available with a default undervoltage lockout and asserted high (PGOOD) output, while the MAX5940B is available with adjustable undervoltage lockout and choice of (PGOOD) and (PGOOD-bar) outputs to enable downstream converters. Both devices include an undervoltage-lockout deglitch filter to allow for rugged operation. The MAX5940A/MAX5940B are available in the extended temperature range (-40°C to 85°C) in a surface-mount 8-pin SO package.

For more information, visit www.maxim-ic.com.


Edited by PETech Staff

Low-Profile Tantalum Capacitors

Vishay Intertechnology Inc.’s two new devices in the 592D family of solid tantalum chip capacitors provide the highest available capacitance values for low-profile tantalum capacitors.

Part of the Vishay Sprague Tantamount® product line, these capacitors are designed for low-profile applications, such as wireless GPRS PCMCIA modem cards and cell phones, requiring very high capacitance.

The devices' low ESR values help to reduce power consumption, while their uniquely compact case size enables the design of lighter, smaller, more portable end products. In some applications, these high-capacitance devices may be used to replace several capacitors with lower ratings, allowing designers to conserve board real estate and decrease component count.

The 592D capacitors released today are available in "X" and "Y" cases with dimensions of 0.570 in. × 0.290 in. [14.5 mm × 7.37 mm] and height profiles of 0.079 in. [2 mm] and 0.098 in. [2.5 mm], respectively. The 592D228X_6R3X2_ in the X case features capacitance of 2200 µF and a maximum current leakage of 139 µA. In the Y case size, the 592D338X_6R3Y2_ offers a capacitance value of 3300 µF and maximum current leakage of 208 µA.

At 6.3 W/Vdc, both devices offer a maximum dissipation factor of 35%, very low ESR of 0.055 Ω and ripple of 1.8 A during operation at +25°C and 100 kHz. Capacitance tolerances of ±10% and ±20% are standard. Tantalum capacitors in the 592D family are conformal coated, feature two 100% tin terminations, and are case-code compatible with EIA 535BAAC and CECC 30801 molded chips. The devices are specified for an operating temperature range of -55°C to +85°C.

For more information, visit www.vishay.com.


Edited by PETech Staff

Online Simulation Tool

Intersil Corp’s new online live circuit simulation tool, iSim™ (pronounced eye-sim), is an Internet-based tool that provides Bode plot analysis using a simple interactive "edit-in-place" schematic based on actual reference designs.

The iSim circuit simulation tool is now part of Intersil's online Technical Design Center, where power supply engineers can find documentation, design resources, other design tools and product information. In addition, Intersil supports designers with reference designs, evaluation platforms, a technical support line and world-class applications engineers.

"iSim has really hit a homerun with our customers' engineers," said Dale Klotz, senior manager of one of Intersil's Design Centers. "Design engineers appreciate the intuitive interface and the fact that there is nothing to download and install on their PC. Designers can store multiple designs in their online account for later recall or further analysis and the engineer can print a complete schematic and bill of materials once finalized. What could be simpler and more convenient?"

"The new iSim tool went live on the Intersil Web site on September 5, 2003," said Jack Clark, director of Intersil's Technical Support Center. "Word-of-mouth has spread the news about iSim, and we already have over 75 design engineers registered as users. Feedback from engineers has been very positive. They especially like being able to quickly and easily optimize power designs online before going to the prototype stage."

Each designer logs in to a personal account in which simulations can be stored and retrieved as needed. Components in schematics can be edited in place and even parasitic components can be modified. Detailed spice-based execution parameters are available for inspection. Simulation results are shown directly in the browser and multiple host servers run the simulations without any need for users to download and install software on their computer. An interactive waveform viewer provides post-simulation data analysis for any selected node and includes interactive marker functions along with data readout. Optimized circuits can be captured with a complete bill of materials ready for hardware prototyping. The iSim tool is supported online with a brief overview and robust FAQs.

Intersil currently has 10 of its most popular PWM controller ICs modeled and ready for online simulation:

  • ISL6225—Dual PWM Controller
  • ISL6520A—simple +5V PWM controller with shoot-thru protection
  • ISL6528—PWM and linear power controller
  • ISL6556A, ISL6558, ISL6559 and ISL6561—2- to 4-phase PWM controllers
  • ISL6569—2-phase PWM controller
  • ISL6721—PWM controller with synchronize and advanced fault protection features
  • HIP6301—2- to 4-phase sync buck PWM controller

More ICs will be added over time. Designers are invited to visit Intersil's iSim Web site, register and login for a test run at www.intersil.com.


Edited by PETech Staff

PTC Thermistors Short-Form Catalog 2004

The new PTC Thermistors Short-Form Catalog 2004 from EPCOS presents a wide selection of ceramic components whose electrical resistance rapidly increases when a certain temperature is exceeded. The catalog describes the PTC thermistors with their key electrical parameters and other technical data.

Ordering codes are listed, and overviews help design engineers find the correct component. Categories featured include PTCs for overcurrent protection, telecom, switching applications, degaussing, motor starting, sensors and heating elements. The resistance feature makes PTC thermistors ideal for applications such as reversible fuses against current overload or as short-circuit protection in motors.

PTC thermistors are in electronic lamp ballasts and switch-mode power supplies for delayed switching, and in picture tubes to de-gauss shadow masks. Motor-starter PTC thermistors are in compressors of refrigerators. Thermal protection of motors and transformers is another example of PTC thermistor versatility. Applications extend to measurement and control engineering, to entertainment, household and automotive electronics, and to data systems and telecom-munications. PTC thermistors are also used as self-regulating heater elements in such items as hot plates and hot-adhesive guns or for auxiliary heating and pre-heating in automobiles.

For a copy of the PTC Thermistors Short Form Catalog 2004 or for additional information, contact EPCOS by phone at 800-888-7728, or visit www.epcos.com.


Edited by PETech Staff

Ultra Miniaturized Capacitor

Murata Electronics is now producing 01005-size chip monolithic ceramic capacitors. Measuring just 0.4 mm x 0.2 mm x 0.2 mm, the GRM02 Series is ultracompact in size. The capacitance ranges between 2 pF and 15 pF for "C0G" characteristics and 1000pF and 10000pF for "X5R" characteristics, respectively. As with the 0201 series, the main application for the 01005 is microwave modules. These microwave modules are used in communication equipment, including cellular phones and other mobile electronic devices.

The demand for high-density surface mounting technology is constantly evolving, particularly for mobile electronic devices. Murata's GRM02 series enhances the process of downsizing and surface-mounting density of mobile electronic devices such as cellular phones. Another highlight of this series is the outer terminal of the device, which features an electroplated structure offering excellent soldering heat resistance.

Murata advanced the processes of printing, laminating and cutting to create a thin-layer dielectric material. This special material allows for a higher capacitance value of 10,000 pF to be achieved in the ultrasmall size 01005.

In addition, the GRM02 series takes up approximately 50% less board space and offers a volume reduction of approximately 70%. The reduction of length from 0.6 mm to 0.4 mm assists in lowering the inductance level making the capacitor fitting for higher frequency applications.

For more information, visit www.murata.com.


Edited by PETech Staff

Boost for Static Transfer Switch Market

The recent power blackout in certain regions within North America resulted in huge loss of revenues for companies. The need for continuous power for critical applications is being felt within the industry and could potentially result in the increased demand for static transfer switch.

New analysis from Frost & Sullivan, World Static Transfer Switch Markets, reveals that this industry-generated revenue totaled $64.2 million in 2002. Total market revenues are expected to reach $76.9 million in 2009.

“End-user sectors such as data centers, telecommunication networks, airport and military bases among others require continuous power for proper functioning,” says Frost & Sullivan Research Analyst Vishal Sapru. “A static transfer switch provides the perfect balance between no power and continuous power.”

The heady growth of data centers, semiconductors and telecommunications industries has also been tempered by the slowdown of the global economy, reducing capital spending on static transfer switches. Nevertheless, the cyclical nature of economic growth suggests that the market will rebound soon.

“In anticipation of increased demand for power quality equipment and independent feeders, manufacturers and service providers of static transfer switches spent excessively on product upgrades and new equipment,” says Sapru.

However, the economic slump discouraged customers in telecommunications and semiconductor sectors from further investing in infrastructure and new devices. Higher static transfer switch budgets are likely to be allotted once the industries win back customers’ confidence and capital markets improve. As the market evolves, there will be many technical innovations and intense competition, compelling manufacturers to be alert to budding trends.

“The markets addressed by current and planned products are rapidly evolving and are characterized by emerging standards and competing technological platforms,” remarks Sapru.

Vendors can keep hold on their market shares by providing reliable, cost- and time-efficient, as well as easily maintainable products. The switches must ensure smooth transfer of current between sources and should be flexible enough to integrate well with different applications.

With competition intensifying, a fall in prices is almost certain. Companies can keep their prices low while also differentiating their products by automating production, expanding globally and introducing new products.

Incorporation of advanced features such as built-in surge suppressors, test switches and emergency power source monitors will drive demand for static transfer switches. Offering multiple functional capabilities including quality control, customer consultation and faster delivery times will also attract a wider range of customers.

The ability of manufacturers to make the right decisions regarding service mix, technical functions, as well as types of customers and manufacturing processes will strongly influence their long-term success. Efficient management of resources, such as investing in plant equipment, will help them meet customers’ and new product designs’ demands for application-specific tests.

For more information, visit www.frost.com.


Edited by PETech Staff

EBS 1/8 Brick Converters

NetPower’s EBS Series of high-efficiency isolated dc-dc converters delivers up to 170 W or 50 A in a standard 1/8 brick package. The converters feature ultrahigh efficiencies (93% at 14 A for the 12 Vout model) along with unparalleled thermal performance. NetPower uses proprietary technologies to optimize the converter design and also maintain a competitive cost structure. The EBS series converters are ideal for applications that require a high output current in a small footprint.

The EBS converters take an input between 42 V to 53 V, and output from 0.8 V to 15 V. They offer tightly regulated output voltages, remote sensing, full protection, and excellent inrush and startup control. The EBS converters also meet the basic insulation requirements of EN60950.

The EBS converters can be used to directly power sensitive electronics loads, or be used in intermediate bus architectures (IBAs). When used in IBAs, they typically have about 20% more effective power capability than an unregulated bus converter with the same current rating, while exhibiting better input and output characteristics.

For more information, visit www.netpowercorp.com or call toll free (866) 638-7693.


By Ashok Bindra, Editor, PETech

Power Electronics Meeting Displays Novel Power ICs and Passives

Several important power ICs and passive components were exhibited at this week’s Power Electronics Technology Conference & Exhibition in Long Beach, Calif. A day’s tour of the exhibition floor exposed some interesting developments in the power arena. While Supertex and Power Integrations were targeting power-over-Ethernet (PoE) applications, International Rectifier unwrapped two new members of its iMOTION integrated design platform. In addition, Canada’s foundry service provider, DALSA Semiconductor, disclosed plans to integrate its MEMS capability with 0.8 micron high-voltage CMOS/DMOS process. Similarly, magnetic component supplier J.W. Miller revealed a new series of high-temperature, high-current toroid power inductors, and Germany’s Kaschke KG demonstrated a new line of miniature transformers, which the company prefers to call smart power transformers. Major players such as Coilcraft Inc.and Datatronics boasted new developments in planar magnetics and surface-mount power inductors and transformers. On the capacitor front, Dearborn Electronics displayed aluminum electrolytic capacitor assemblies with a range of 48 µF to 20,000 µF and 10 Vdc to 500 Vdc capabilities.

Speaking of PoE, Supertex unveiled its first entry in to the arena. The power semiconductor supplier showed a PoE interface controller for the PD (Powered Device) section of the IEEE802.3af protocol. Offering complete power management and protection for PDs, the HV110 features a 400-mA inrush limit and fault current limit, as well as minimum current shutdown. Because the internal power switch uses scaled current-mirror technology, it eliminates the need for an external sense resistor. Thus, it provides highly accurate current sensing at the high and low operating conditions. To eliminate the need for any external high-voltage protection devices at the input of the controller, the HV110 implements a rugged high-voltage junction isolated process. Furthermore, it’s encased in a thermally improved DPAK-5 package.

Another newcomer to the PoE fray is Power Integrations. The company announced dc-dc converters targeting the PD side of the PoE market. As new members of its popular DPA-Switch family, the DPA423G /4G/5G converters have been tailored to meet the dc-dc requirements of the PD side of the new standard. Integrating a 220-V MOSFET, PWM control and line undervoltage lockout (UVLO), along with current sensing, the new parts cut some 20 to 50 external components. Other salient features include 300- kHz to 400-kHz pin-selectable fixed frequency, 16-Vdc to 75-Vdc input voltage range, and up to 23-W output capability. When used with synchronous rectification, it can offer greater than 90% efficiency.

On another front, International Rectifier demonstrated two versions of a single chip motion control IC. Expanding its portfolio of iMOTION solutions, the two new additions have been architected to eliminate the task of programming, and thereby slash the time to market high-performance ac drives. According to IR’s director of engineering, digital control IC design center Toshio Takahashi, the IRMCK201/203 incorporates a dedicated motion control engine (MCE) that eliminates software programming, which is a complex task under traditional motor drive controls that rely on DSPs or MCUs. Designed to be compatible with other chipsets in the platform, the IRMCK201 features an encoder feedback based closed loop current and velocity control for servo applications, while IRMCK203 is a digital control for sinusoidal current-based sensorless drives. Consequently, the IRMCK203 enables the design of ultrahigh-speed (100,000 rpm) and wide range (›20:1) ac permanent magnet motor drives with sensorless control. While the IRMCK201 is housed in a 100-pin QFP, the IRMCK203 is offered in an 80-pin QFP package.

Prompted by the demand for better and better magnetics in power supplies designed for harsh environments, a few suppliers boasted components that raised the performance bar. For instance, J.W. Miller introduced a high-temperature toroid power inductor with 200°C capability. The manufacturer’s new 2100HT/2200HT/2300HT series of high-temperature, high-current toroid power inductors offers an operating temperature range of –55°C to 200°C. In addition, the new power inductors feature a self-shielding design that drastically cuts magnetic flux interference to the adjoining area. J.W. Miller’s chief design engineer attributes this performance to the use of a proprietary high-temperature iron powder core material.

Likewise, Metglas, a subsidiary of Hitachi Metals America Ltd., displayed a novel nanocrystalline soft magnetic core material called FINEMET. Key applications for the new core material include EMI filters, high-frequency power transformers, saturable core for magnetic amplifier SMPS, and pulsed power cores.


Edited by PETech Staff

International Rectifier Breaks Ground On New Site in Xi’an China

International Rectifier Corporation recently broke ground on a new manufacturing site in Xi’an, China.

The new assembly and test facility is anticipated to become operational in early 2005 for the manufacturing of key power management components needed to support the world’s growing requirement for power supplies, motion control, personal computers and a broad range of other consumer electronic products.

The new site will be located in the Chang’an Technology Park in Xi’an’s High Technology Industrial Development Zone. In addition to the new manufacturing facility, the company maintains design and applications centers in Xi’an, a trading company in Shanghai, and multiple sales offices throughout China. International Rectifier operates facilities in 19 other countries throughout North America, Europe and Asia.

For more information, visit www.irf.com.


Edited by PETech Staff

MGE Selects DeviceView M2M Remote Device Management Solution

emWare® Inc., Lantronix® and MGE UPS Systems Inc. have signed a working agreement to add remote service capabilities to MGE's full line of enterprise power protection products. MGE is working with emWare to integrate a bundled solution comprised of emWare's DeviceView Service and Lantronix' Device Servers with MGE's Data Center Enterprise Power Systems, which include the Comet 150, Comet S31, Comet Extreme, Galaxy 3000, Galaxy PW and EPS 6000 Uninterruptible Power Supplies (UPS) as well as Power Management Modules (PMM) and Epsilon Static Transfer Switches (STS).

The DeviceView Service is an enterprise M2M remote device management solution that allows companies, such as MGE, to easily, cost-effectively, and securely exchange information with their equipment anywhere in the world. Devices and equipment that are connected to a Lantronix UDS100 Device Server can contact the DeviceView Service and exchange relevant device data. This data is then stored in a database for later retrieval using DeviceView's enterprise application. Service technicians can access this information to determine the operational status of the remote equipment and take appropriate action if the equipment falls outside acceptable levels of operation. The DeviceView Service also continuously monitors this information and can notify the appropriate personnel when an alert condition exists on their equipment.

For more information, visit www.mgeups.com, www.emware.com or www.lantronix.com


Edited by PETech Staff

Passive Component Catalog

RCD Components Inc. recently released its 2004 Full-Line Catalog redesigned to help design engineers and purchasing agents make faster and more informed buying decisions. RCD’s new catalog boasts more than 100 new passive product types, providing the industry’s most comprehensive single source for high-quality passive products.

The 116-page catalog redesign has a fresh new look, and features many enhancements, including improved product indexing, expanded performance graphs and product application notes.

RCD’s new catalog redesign characterizes a year of accomplishments for the manufacturer, which celebrated their largest product expansion in its 30-year history.

Print copies of RCD’s catalog are available at no charge from www.rcdcomponents.com.


Edited by PETech Staff

Expanded CleanSource DC Energy Storage Systems

Active Power has responded to growing market requirements for continuous power solutions by enhancing its popular CleanSource dc line of battery-free energy storage systems to include expanded power levels and incorporate several changes in the evolving product line. Based on Active Power’s proven flywheel technology, the new models provide tightly regulated, adjustable dc voltage to replace or augment batteries configured with uninterruptible power supply (UPS) systems backing up critical applications in the 100-kW to 2000-kW power ranges.

The new and enhanced models are available with unit power ratings of 100 kW, 140 kW, 200 kW, 250 kW, 425 kW and 500 kW, and can be paralleled in combinations up to 2000 kW. They accept an input float voltage from 400 Vdc to 600 Vdc to supply a charging current of 15 A to 100 A per flywheel. User-adjustable output voltage can be set from 360 Vdc to 550 Vdc with ±1% steady-state voltage regulation. Unlike batteries that must be maintained as close as possible to 20°C to avoid performance degradation, the CleanSource DC models are designed to operate comfortably from 0°C to 40°C.

For more information, visit www.activepower.com.


Edited by PETech Staff

Integrated Single-Stage Active Power Factor Correction and Isolated Step-Down Controller

ON Semiconductor’s new NCP1651 is an integrated controller that facilitates the simplest possible implementation of power-factor corrected, isolated power converters and reduces both part count and overall design costs for power conversion applications such as battery chargers and distributed power systems up to 200 W.

The NCP1651 provides a low-cost, low component-count solution that is compliant with IEC1000-3-2 harmonic standards for isolated ac-dc converters with mid-high output voltage requirements. Fixed-frequency continuous conduction mode (CCM) operation simplifies the design of the input Electromagnetic Interference (EMI) filter and optimizes efficiency. The controller also can operate in discontinuous conduction mode for maximum design flexibility.

Compared to a conventional power conversion design that uses a PFC controller followed by a dc-dc converter, the unique single-stage design of the NCP1651 eliminates one entire power switching section including the boost inductor, the power MOSFET, the high-voltage capacitor and ancillary components. Unlike other single-stage solutions, the NCP1651 approach reduces the power stage requirements to a minimum: a single magnetic element, a switch, a diode and a capacitor. An internal high-voltage start-up circuit reduces component count further by eliminating external start-up circuitry. Other features of the NCP1651 include a high accuracy multiplier that reduces over-design of the power components, an overtemperature shutdown and an undervoltage lockout.

For more information, visit www.onsemi.com.


Edited by PEtech Staff

POL DC-DC Converters

Artesyn Technologies Inc. has extended its point-of-load (POL) converter range with options offering a third more power, without any change to form-factor or footprint. Providing a single output that may be adjusted for virtually every low-voltage silicon in use today, at currents of up to 20 A or 40 A, “C-class” nonisolated dc-dc converters are optimized for cost-critical applications through open-frame, single-board construction. The new components provide OEMs with valuable support for creating attractive products for cost-sensitive markets such as computers and peripherals.

Flexibility of use is further aided by a choice of either 12-V or 5-V input voltages, suiting the different intermediate dc bus voltages that tend to be used in application sectors such as computing and telecommunications.

Known as SIL20C and SIL40C, Artesyn’s new 20-A and 40-A POL converters feature wide adjustable outputs of up to 0.9 V to 5 V, which are set to the required value by a single external resistor. The options complement Artesyn’s existing 6 A, 15 A and 30 A offering—providing developers with a broad selection of standard parts that allow the power supply to be matched closely to the load. The components additionally extend the available output power from 150 W to 200W, giving developers true flexibility to accommodate changes in power budget without redesigning PCBs.

For more information, visit www.artesyn.com.


Edited by PETech Staff

Ticona GmbH and LPFK Laser & Electronics Sign Agreement

LPKF Laser & Electronics has entered a know-how and license agreement with Ticona (Kelsterbach, Germany) for the material Vectra®LCP (Liquid Crystal Polymer). The agreement enables Ticona to modify their LCP material for the LPKF Laser Direct Structuring (LDS) process to produce 3D-MID circuits.

There has long been a desire to deposit conductive paths directly on molded plastic structures, combining the electrical and mechanical functions in one component to form an injection-molded circuit carrier. With the combination of the LPKF LDS process and the new Vectra polymer material, this technology is easily accomplished. Now, the electronics housing substitutes for the conventional circuit board, encouraging miniaturization. This laser-based process is realized with few manufacturing steps. The structure is molded in a standard mold using the Vectra proprietary plastic, the desired interconnect pattern is directly written on the resulting molded part using an LPKF laser system, and the conductive paths are plated using industry standard methods. The plating adheres only where the plastic has been activated by the laser. Due to the high temperature resistance, the circuit structures on this LCP material are solderable. This technology is ideal for mobile communication devices, hearing aids and sensory technology for automobile electronics.

For more information, visit www.lpkfusa.com.


Edited by PETech Staff

String Potentiometer and String Encoder Engineering

GuideTechnical details on the operation, benefits, and use of cable-type position transducers are available free of charge from SpaceAge Control. The String Potentiometer and String Encoder Engineering Guide, 12 pages in length and with 18 color illustrations, enables engineers and technicians to know what applications are best-suited for string potentiometers and string encoders and what the limitations of the technology are.

The publication gives displacement measurement background and techniques on subjects such as accuracy, environmental protection, installation, and lifetime. Application examples ranging from the Delta IV and F-22 to excavators and earth boring equipment are covered. In addition, product-specific features and benefits are summarized, including:

  • DirectConnect™ technology eliminates backlash resulting from spring-loaded and clutched designs.
  • AccuTrak™ threaded cable spool ensures repeatability from cycle to cycle.
  • FastInstall™ design allows 360-degree mounting rotation to eliminate special fixturing.
  • UniExit™ cable exit gives 270-degree displacement cable movement flexibility

The publication is freely available by request at spaceagecontrol.com/req054b.htm


Edited by PETech Staff

Clock Oscillator

The DS1086L spread-spectrum EconOscillator™ from Dallas Semiconductor is the world's smallest low-EMI, 3-V, all-silicon clock oscillator. With six user-programmable spread settings from 0% to 8%, it offers up to 23-dB reduction in radiated emissions (RMS voltage) relative to crystal oscillators.

The DS1086L can be used as a stand-alone oscillator to generate clock outputs from 4.9 kHz to 66 MHz. It has a power-down mode and an output-enable control for power-sensitive applications. The DS1086L can simplify or eliminate shielding and filtering while reducing cost and minimizing design time. In addition, the DS1086L operates in the 2.7-V to 3.6-V range and is available in the tiny 8-pin microSOP.

For more information, visit www.maxim-ic.com.


Edited by PETech Staff

Catalog Features EMC Components for Power Line Applications

The new 2004 short-form catalog of EMC Components for Power Line Applications gives an overview of EPCOS chokes and filters for use in filtering noise from power lines. The catalog describes the components with their key electrical parameters and other technical data. Ordering codes are listed for all products, and overviews help design engineers find the correct component.

Innovations include the new compact B84143B*S080/S081 series of 3-line filters with current strengths of 180 A to 1600 A. With the extension of the B84143A*R105 series, filters from 8 A to 150 A offering an excellent price/performance ratio are now available.

The catalog also presents a new generation of filters for shielded rooms, which are distinguished by their compact design and good price/performance ration, attaining stop-band attenuations of over 100 dB in the range from 15 kHz to 40 GHz.

For more information, visit www.epcos.com. 11/3/2003

Edited by PETech Staff

Synchronous Step-Down Regulator

Linear Technology’s new LTC3408 is a high-efficiency, 1.5-MHz, synchronous buck regulator with an integrated bypass MOSFET that can deliver up to 600 mA of continuous output current from a tiny 8-lead DFN package. The on-chip bypass MOSFET has an RDS ON of only 0.08 Ω, minimizing power loss in the bypass mode. The LTC3408 uses a constant frequency, current mode architecture, which operates from an input voltage range of 2.5 V to 5 V, making it ideal for single cell Li-Ion cellular applications. The output can be dynamically programmed from 0.3V to 3.5V to optimize the efficiency of CDMA and WCDMA power amplifiers, increasing battery life. At output voltages above 3.6 V, an internal bypass P-Channel MOSFET transistor connects V OUT directly to BATTERY with a dropout of less than a 50 mV (at 600 mA), minimizing power loss through the inductor. Its 1.5-MHz switching frequency allows utilization of tiny, low-cost capacitors and inductors less than 1 mm in height. The combination of tiny externals and a 3-mm × 3-mm DFN package makes the LTC3408 optimal for space-constrained cellular phones.

For more information, visit www.linear.com.

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