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Battery-Charger IC

Texas Instruments' (TI's) bq24721 integrated battery-charge controller features a system management bus (SMBus) interface aimed at multicell, multichemistry battery packs used in portable applications.

TI's highly accurate and power-efficient bq24721 charge-management device easily interfaces to a system's host controller through an SMBus communications interface. The charger offers 0.4% accuracy on charge-voltage regulation and 2% accuracy on current-amplifier outputs. Using a synchronous NMOS-NMOS rectifier, the easy-to-design device can achieve power efficiencies up to 94%.

The bq24721 is available in a 32-pin, 5-mm × 5-mm QFN package. Pricing is $4.90 in 1000-piece quantities.
Texas Instruments
Dallas, Texas

www.ti.com

Dual High-Voltage Rectifier

Vishay's Schottky barrier rectifiers based on trench MOS technology are useful as a rectification circuit or an ORing diode in redundant switch-mode power supplies. The VTS40100CT from Vishay is optimized for 100-W to 300-W high-frequency switch-mode power supply applications, and its package is a TO-220AB case rated for 40 A (2 × 20 A) and 100 V. Its voltage drop of 0.375 V at 5 A and 125°C reduces conduction power losses.

The V40100P is also rated for 40 A (2 × 20 A) and 100 V, with a TO-247AD case and an even lower typical forward voltage drop of 0.372 V under the same conditions. That forward voltage drop is matched by the V50100P, which also has a TO-247AD case and a higher rating of 50 A (2 × 25 A).

The V30100S and VF30100S are both rated for 30 A (1 × 30 A) and 100 V, with a typical forward voltage drop of 0.385 V at 5 A and 125°C. The V30100S is packaged in a TO-220AB case and the VF30100S in a fully molded ITO-220AB case.

Pricing in 1000-piece quantities starts at $1 for the V30100S and VF30100S, $1.50 for the VTS40100CT, $2 for the V40100P and $2.50 for the V50100P.
Vishay Intertechnology
Malvern, Pa.

www.vishay.com

General-Purpose Rectifier

Central Semiconductor's CMMR1 series of 1-A general-purpose rectifiers is housed in the flat, lead SOD-123F surface-mount package. This series has peak repetitive reverse voltages of 200 V (CMMR1-02), 400 V (CMMR1-04), 600 V (CMMR1-06) and 1000 V (CMMR1-10).

Typically, these rectifiers are packaged in the much larger SMA case. The CMMR1 series in the SOD-123F utilizes 49% less board space than the SMA and has a 57% lower profile. The CMMR1 series is available bulk packed or in 3000-piece quantities on 7-in. tape and reel. Prices start at $0.06 each for 3000 pieces on a 7-in. reel.
Central Semiconductor
Hauppauge, N.Y.

www.centralsemi.com

Thick Film Resistors

The Super RCX series of thick film, wraparound surface-mount chip resistors from IMS offers twice the power handling in the same footprint for users who need more power, but don't want the higher cost of beryllia and aluminum nitride. These resistors eliminate the need for redesign to accommodate higher power by maintaining the same resistor size and footprint. Resistor sizes available include 0402, 0603, 0805, 1206 and 2512.

The Super RCX series of resistors are available in bulk, tape and reel, and waffle pack.
IMS
Portsmouth, R.I.

www.ims-resistors.com

Surface-Mount Inductors

The Coiltronics brand of high-current HC8LP surface-mount inductors from Cooper Electronic Technologies, a business unit of Cooper Bussmann, are 3.5 mm in height with a wider inductance range and higher inductance values from 0.17 µH to 47.9 µH.

The HC8LP inductors have a current range from 1.8 A to 29 A and a frequency range up to 500 kHz. They are RoHS compliant and use high-temperature iron-powder iron material and use a nonorganic binder to eliminate thermal aging problems associated with other iron-powder inductors.
Cooper Electronic Technologies
Boynton Beach, Fla.

www.cooperindustries.com

Rad-Hard DC-DC Converters

International Rectifier's LS Series of low-voltage, single- and dual-output dc-dc converter modules are radiation-hardened (Rad-Hard). The modules, which include an internal MIL-STD-461C, CE03-compliant EMI filter, deliver isolated output voltages from 1.5 V to 15 V with typical efficiency ratings up to 83%.

By including the EMI filter, the modules simplify power-management circuits used in satellite applications, scientific missions that have long life requirements of up to 15 years or radiation design requirements of 100 Krads.

Pricing for the LS Series starts at $6500 each in production-unit quantities.
International Rectifier
El Segundo, Calif.

www.irf.com

Stepdown DC-DC Converter

Linear Technology's LTC3410 is a high-efficiency, 2.25-MHz synchronous-buck regulator that can deliver up to 300 mA of continuous output current from an SC70 package.

Using a constant frequency and current-mode architecture, the LTC3410 operates from an input voltage range of 2.5 V to 5.5 V, making it ideal for single-cell Li-ion or multicell alkaline/NiCd/NiMH applications. It can generate output voltages as low as 0.8 V, allowing it to power the latest generation of low-voltage DSPs and micro-controllers. Its 2.25-MHz switching frequency enables the utilization of tiny, low-cost ceramic capacitors and inductors less than 1 mm in profile. For noise-sensitive applications, the LTC3410B provides a lower noise pulse-skipping mode, yet still needs only 200 µA of quiescent current.

The LTC3410ESC6 and the LTC3410BESC6 are both in six-lead SC70 packages. Pricing starts at $1.50 each for both the LTC3410 and LTC3410B in quantities of 1000.
Linear Technology
Milpitas, Calif.

www.linear.com

1.5-A Battery Charger

Semtech's SC804 is a linear, single-cell Li-ion battery charger with battery pack and adapter flexibility that enables lower design costs for portable devices. The SC804 integrates a cold temperature offset (CTO) pin that allows designers to adjust the charging temperature range with a simple external resistor divider. With this capability, a single board design can be used in multiple applications that require different temperature range limitations for charging.

The SC804 has an input voltage range of 3 V to 14 V, better protecting portable systems from transients introduced from 12-V adapter overshoots or from the use of improper third-party adapters. Undervoltage lockout (UVLO) has been lowered to 3 V to work well with current-limited adapters.

As a fully integrated device, the SC804 features a FET pass transistor, reverse-blocking diode, sense resistor and thermal protection. Other features of the device include an integrated timer and programmable pre-charge, fast-charge and termination current settings. Two variants of the device are available supporting different output voltages. The SC804 base device features a 4.2-V output and the SC804A features a 4.357-V output.

The SC804 is packaged in a 4-mm × 4-mm MLPQ package. The SC804 is priced at $1.43 each in 1000-piece quantities.
Semtech
Camarillo, Calif.
www.semtech.com

600-mA DC-DC Converters

ON Semiconductor's NCP1521 and NCP1522 600-mA dc-dc stepdown converters are optimized for portable applications powered from one-cell Li-ion or three-cell alkaline/NiCd/NiMH batteries. The devices include integrated soft-start, cycle-by-cycle current limiting and thermal shutdown protection. Automatic switching between PWM and PFM modes provides improved system efficiency.

The NCP1521 switches at 1.5 MHz and delivers up to 96% efficiency; the NCP1522 switches at 3 MHz, and delivers up to 93% efficiency. These high frequencies allow for use of lower value inductors and output capacitors, which result in a physically smaller subsystem solution.

Both devices are currently in production. They are packaged in 3-mm × 3-mm TSOP-5 packages. The NCP1521 is priced at $0.60 each and the NCP1522 is priced at $0.65 each, both in quantities of 3000.
ON S emiconductor
Phoenix
www.onsemi.com

Voltage Supervisors

A family of 10 voltage supervisors (the MCP1316 to MCP1322) from Microchip Technology offers a watchdog timer, manual reset, and multiple combinations of push-pull or open-drain reset outputs. These chips also feature factory trip points from 2 V to 4.7 V in 100-mV increments, in a five-pin SOT-23 package.

The family monitors microprocessor activity in digital systems. They operate at input voltages from 1 V to 5.5 V and have a low current consumption of 5 µA typical. The devices operate within the extended industrial temperature range of -40°C to 125°C.

These voltage supervisors are available for sampling. Production orders also can be placed for the voltage supervisors and are priced at $0.42 each in 10,000-unit quantities.
Microchip Technology
Chandler, Ariz.

www.microchip.com

Multilayer Ceramic Capacitor

Taiyo Yuden (USA) now offers two additional high-capacitance multilayer ceramic capacitors (MLCC): the 100-µF device in EIA 1206 case size and the 47-µF in 0805. Ideal for smoothing CPU power circuits, the 100-µF device meets the market demand for higher capacitance in smaller form factors. The 47-uF device is an ideal solution for high-density surface-mount requirements in cell phones and other ultra-portable designs.

Key specifications of the mass-produced AMK series MLCCs include ±20% capacitance tolerance, ±15% capacitance change and a rated voltage of 4 V. Available in production quantities, samples of the 100-µF device (AMK316BJ107ML) are available at $0.80 each, and the 47-µF device (AMK212BJ476MG) is available at $0.50 each.
Taiyo Yuden (USA)
Schaumburg, Ill.

www.yuden.us

Power Controllers

The 4800 Power Control Series from MRV Communications are -48-Vdc additions to the out-of-band networking product family, which offer carriers and utilities an intelligent power distribution and remote power-control solution to maximize operational up time. The three versions of the series are: the 4805-XLS, 4805/35-XLS and 4870-XLS.

All 4800 Power Control Series models feature out-of-band connectivity that allows administrators to remotely power on, power off or reboot attached equipment. Accessed through MRV's LX Series Secure console servers, enhanced LX Series security capabilities include SSH V2SSHv2 Secure Shell secure remote terminal, SNMP V3, Radius, SecurID, TACACS+ and compliance with the FIPS 140 federal standard for products supporting encryption.
MRV Communications
Chatsworth, Calif.

www.mrv.com

Nonisolated DC-DC Converter

The NQ10W50PKA07 dc-dc converter from SynQor is optimized to provide high efficiency, fast transient response and low output noise in a small package. The series delivers a full 7 A of output current and is perfect as a low-voltage POL converter in intermediate bus architecture (IBA) applications.

These converters have a 10.2-V to 13.2-V input voltage range and a 0.75-V to 5-V output voltage range. The modules are up to 94% efficient and can supply the full rated output of 7 A up to 85°C with just 100 LFM (0.5 m/s) of airflow. The converters have a low-profile height of 0.232 in. and a footprint of 0.4 in. × 0.9 in.

The NQ10 is available in different variations: a discontinuous mode to achieve high conversion efficiency at both low and high output voltages, or a forced continuous mode to achieve an extremely fast transient response and low output-voltage ripple. Both modes have an option to use an internal reference point, which provides ±5% margining using digital input signals, or an external reference point, which allows custom voltages to be set using an external reference voltage. The NQ10 modules are priced at $14.60 each in OEM quantities.
SynQor
Boxborough, Mass.

www.synqor.com

Class 2 Control Transformers

Foster Transformer's line of Class 2 Control Transformers with multi-tap primary windings is suited for industrial and commercial applications. Designed to Class 2 not inherently limited specifications, these unique transformers are precision layer wound for longer service life. They feature an integral 3AG fuse holder and convenient 0.25-in. × 0.032-in. QC tab connections for fast and easy installation.

Standard models are available with a wide range of primary input voltages at 50 Hz/60 Hz, with a standard output of 24 V and 50 VA. Each model includes UL-recognized Class 130 (B) insulation.
Foster Transformer
Cincinnati

www.foster-transformer.com

Board-Mounted DC-DC Converters

The E48SH high-powered, eighth-brick converter from Delta Electronics is the latest addition to its Delphi Series of board-mounted dc-dc power converters. The 48-V input, single-output, isolated dc-dc converter delivers up to 50 A of output current or 120 W of power in an industry-standard footprint and pin out.

The converter operates from an input voltage of 36 V to 75 V and is available in output voltages from 1 V to 15 V. Typical efficiency for this module with a 12-V, 10-A output is 93.5%. The E48SH costs $41 each in quantities of 1000.
Delta Electronics
Taipei, Taiwan

www.delta.com

Converter for RF Amplifiers

The JHW250 series of dc-dc converters from Tyco Electronics Power Systems can deliver up to 250 W of output power in an industry-standard half-brick format for radio-frequency power-amplifier applications. The series of power modules are isolated dc-dc converters that operate over a wide input voltage range of 36 Vdc to 75 Vdc, and provide a single, precisely regulated output of 30.2 V.

These modules incorporate synchronous rectification technology and innovative packaging techniques to achieve typical efficiencies of 92% at 30.2 V with full load.

The converters are rated for a wide operating temperature range of -40°C to 85°C in an industry-standard half-brick package of 57.9 mm × 61.0 mm × 12.7 mm. Each module in the JHW250 series is priced at $86.10 in quantities of 1000.
Tyco Electronics Power Systems
Dallas

www.power.tycoelectronics.com

High-Current Solenoids

Zettler Controls' ZCS1-70/71 and ZCS1-120 Series Solenoids are capable of handling high currents of up to 100 A. The ZCS1-70/71 features SPNO or SPDT contacts, an enclosed dust-resistant case, longer encasement to allow lower heat rise and sensitive operation (ZCS1-71), coil voltage ranging from 6 Vdc to 48 Vdc, and the option of isolated or grounded coils. The ZCS1-70/71 offers two duty cycles, continuous and intermittent, with an approximate power consumption of 10 W and 25 W, respectively.

The ZCS1-120 Series features weather-resistant casing, SPNO contacts, coil voltage ranging from 6 Vdc to 48 Vdc, and versatile mounting/termination options. It also offers two duty cycles with approximate coil power consumption of 8.1 W continuous and 14.4 W intermittent. The ZCS1-120 is capable of handling low current requirements as well as high currents.
Zettler Controls
Aliso Viejo, Calif.

www.zettlercontrols.com

Solid-State Relay

American Zettler's latest series addition to its SIL package Solid-State Relays is the SGX-41F. Pin-out is compatible with the standard OAC type I/O module with models that can switch loads up to 4 A at voltages up to 400 Vac. The device also has options of input voltage — a choice of 3 Vdc to 15 Vdc or 15 Vdc to 32 Vdc — and turn on at zero cross or random phase.

Features include an internal snubber, dual SCR ac or TRIAC ac output, and a maximum blocking voltage of 800 V. The device has a minimum off-state (dV/dt) capability of at least 500 V/µs. Additional features include: high surge capacity and a 4000-Vac dielectric strength between input and output.

Pricing starts at $4.96 each in quantities of 1000.
American Zettler
Aliso Viejo, Calif.

www.azettler.com

High-Speed CMOS Optocouplers

Fairchild Semiconductor's FOD0708 (single-channel) and FOD0738 (dual-channel) 15-Mbaud optocouplers offer a high common-mode noise rejection (CMR) rating while providing high bandwidth (15 Mbps). Fairchild's patented Optoplanar technology reduces package capacitance, leading to a guaranteed 25-kV/µs minimum common-mode rejection (CMR) rating. Unlike open collector bipolar-equivalent solutions, these optocouplers feature a push-pull detector that eliminates the need for a pull-up resistor and the power-consuming current it draws.

The optocoupler's high-speed LED and a high-speed photodetector utilize Fairchild's proprietary 0.8-mm CMOS technology. Pricing for the FOD0708 is $1.45 and for the FOD0738 is $2.83, both for 1000-piece orders.
Fairchild Semiconductor
South Portland, Maine

www.fairchildsemi.com

Battery Fuel Gauge

Dallas Semiconductor's DS2781 stand-alone fuel gauge operates directly from a 2.5-V to 10-V power source. It calculates remaining capacity for 1- or 2-cell Li-ion and Li-polymer battery packs. The device includes 16-bit current measurement, and 11-bit voltage and temperature measurements.

On-chip nonvolatile memory stores cell characterization data and application performance parameters. The device uses this measured and stored data to calculate the remaining battery capacity.

The fuel gauge is available in a lead-free, eight-pin TSSOP package small enough to fit on the side of a prismatic battery cell. Pricing for the DS2781 starts at $2.90 each in quanitities of 1000.
Dallas Semiconductor
Dallas

www.maxim-ic.com