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DC-DC Switching Power Supply
Taiyo Yuden (USA) unveils the AAD-130DC, a 130-W dc-dc switching power supply providing an input voltage range of 36 Vdc to 72 Vdc and a choice of four available outputs with current ratings from 1.5 A to 16 A. Measuring just 5 in × 3.14 in × 1.25 in, the AAD-130DC is the latest model in Taiyo Yuden's family of modular, high-density switching power supplies for data communications, telecommunications and other 1U-height applications.
The addition of a chassis increases durability and reliability by reducing component temperatures. The convection-cooled version of the AAD-130DC provides 80 W of output power. An optional 15 CFM cooling fan also is available, enabling the device to provide 130 W of output power. The AAD-103DC costs $70 each in OEM quantities. Delivery time is four to eight weeks ARO.
Taiyo Yuden (USA)
San Marcos, Calif.
Maxim Integrated Products introduces the MAX8729, a fully integrated controller optimized to drive multiple cold-cathode fluorescent lamps (CCFLs) used in LCD monitor and TV applications. The MAX8729 drives multiple lamps with a half-bridge inverter consisting of two external n-channel power MOSFETs. It operates in resonant mode during striking, then switches to fixed-frequency operation after the lamps are lit, ensuring reliable striking and reducing transformer stress.
The MAX8729 achieves a 10-to-1 dimming range by switching the CCFL using digitally adjusted PWM (DPWM), which can be controlled with an analog voltage on the CNTL pin. Synchronization and phase-shift features for both the switching and DPWM frequencies permit daisy chaining of up to six MAX8729s. Prices start at $4.53 each in quantities of 1000. A pre-assembled MAX8729 evaluation kit with recommended external components is available.
Maxim Integrated Products
BI Technologies, a TT electronics company, has recently developed the HM70 Series, a series of high current, low-profile power inductors that are rated for operation to 180°C, providing design engineers with a compact shielded inductor that delivers stable electrical performance even at elevated temperatures. The maximum operating temperature range for these surface-mount devices is -40°C to 180°C, with derating for temperatures above 130°C.
The HM70 Series inductors are ideal for under-the-hood automotive and server/router applications that must operate in high-temperature environments, as well as for compact VRM and dc-dc converter modules. The HM70 Series inductors feature typical inductance values from 0.70 µH to 2.10 µH (±20%, measured at 100 kHz), with dc resistance values from 1.05 mΩ to 4.71 mΩ. Rated current ranges from 12 Adc to 34 Adc at 25°C.
The HM70 Series inductors are available in seven package sizes. Typical pricing for the HM70 Series is $0.67 each in quantities of 10,000.
Triple-Output Charge Pump Regulator
Advanced Analogic Technologies announces the AAT2820, a triple-output charge pump regulator for battery-powered portable devices. Targeted for TFT LCDs and CCD image sensors in handheld products, the power management device generates three regulated output voltages for turn-on gate-drive bias, turn-off gate-voltage bias and logic voltage. Both VON and VOFF output voltages use external diode and capacitor multiplier stages to regulate output. By eliminating the use of high-profile inductors, the AAT2820 supports the design of ultrathin solutions only 0.8-mm high.
Operating at a high 1-MHz switching frequency, the AAT2820 also allows designers to use extremely small, low-profile external capacitors. Available in a lead-free TDFN44-16 package, the AAT2820 costs $1.53 each in 1000-piece quantities.
Advanced Analogic Technologies
Nonisolated DC-DC Converters
Bourns Inc. has released an extended range of nonisolated dc-dc converters in industry-standard packaging. The company's nonisolated converters provide the low voltages needed to support core logic, ASICs, microcontrollers and microprocessors. These high-efficiency converters provide improved regulation and superior dynamic response. Bourns Switch Power Product Group recently added the X and XT series of low-cost nonisolated dc-dc converters, which utilize the latest buck topologies and synchronous rectification to achieve efficiencies up to 95%. Nominal input voltages are 3.3 V, 5 V and 12 V, with output voltages of 0.75 V to 5.5 V dependent on input voltage. Output currents begin at 0 A, and have maximum outputs of 5 A, 6 A, 10 A and 16 A for any combination of the voltages listed previously.
Available in industry standard RoHS-compliant SIP and compact SMD configurations, pricing for the X and XT series in quantities of 1000 pieces is $4.75, $5.25, $8.75 and $10.50 for the 5-A, 6-A, 10-A and 16-A devices, respectively.
Splayed Pin-Fin Heatsink
Cool Innovations has introduced the UltraCool P line of splayed pin-fin heatsinks. UltraCool P pin fins feature an array of round pins that are splayed outward. They possess the same large surface area of conventional pin-fin heatsinks, but are not as densely configured. The sparse configuration enables surrounding airflows to enter and exit the pin array in a significantly more-efficient manner. As a result, splayed pin fins are able to offer a 20% to 30% performance premium over conventional pin-fin heatsinks when operating in low-airspeed environments and in the natural convection mode.
Available in a wide variety of standard sizes — ranging in footprint from 0.5 in × 0.5 in to 2 in × 2 in and in height from 0.2 in to 1.1 in. — the splayed line is suitable for any surface-mount package type.
Integrated Thermal and EMC Simulation
Flomerics has released Version 6 of its integrated analysis environment for physical design of electronics, with improved communication between thermal and electromagnetic compatibility (EMC) simulation. The latest Flotherm and Flo/EMC software packages further reduce the time required for integrated simulation by generating two different meshes separately optimized for thermal and EMC simulations. The need for two meshes arises from the differences between the physics applied to thermal and EMC problems, which require grid refinement in different places. Flotherm and Flo/EMC Version 6 allow users to optimize thermal and EMC meshes independently, and geometric feature changes in the design automatically propagate between the models while leaving mesh refinements intact.
Flomerics also offers a new step-by-step guide that explains how engineers can integrate thermal and EMC design to help identify and resolve system-level mechanical design issues.
Hampton Court, Surrey, U.K.
Two- and Three-Phase PWM Controllers
Intersil Corp. announces the two-phase ISL6310 and three-phase ISL6308 pulse-width modulation (PWM) controllers with high-current, integrated MOSFET drivers and high system accuracy. They are optimized for server and embedded system peripheral voltage regulation. The output can be programmed internally to 0.6 V, 0.9 V, 1.2 V or 1.5 V, or externally with a precision reference. A unity-gain differential amplifier performs the voltage sensing, and a single external resistor determines the output voltage offset.
These devices also offer a programmable voltage droop pin for applications such as chipset cores that don't require the power converter voltage droop or prepositioning often found in CPUs. The integrated MOSFET gate-driver bias voltage of the ISL6310 and ISL6308 is programmable from 5 V to 12 V, allowing for the optimum tradeoff between the MOSFET switching and conduction losses.
The ISL6310 is available now in a 32-lead QFN standard or lead-free package and is priced at $1.80 each in quantities of 1000. The ISL6308 is available now in a 40-lead QFN standard or lead-free package and is priced at $2.25 each in quanitities of 1000.