Battery charger minimises power dissipation

Edited by the Electronicstalk editorial team Feb 28, 2011Linear Technology has introduced the LT3651-4.2, a 4A monolithic synchronous buck battery charger for one-cell li-ion/polymer batteries used in industrial hand-held instruments and notebook computers.
The LT3651-4.2 accepts inputs up to 32V with a 40V absolute maximum rating for added system margin.

Linear Technology has introduced the LT3651-4.2, a highly efficient, 4A monolithic synchronous buck battery charger for one-cell li-ion/polymer batteries
Charge current is programmable and dynamically adjustable up to 4A; fully integrated synchronous power devices minimise power dissipation and save board space.
User-selectable timer or C/10 termination requires no external microcontroller and simplifies the design.
The LT3651-4.2 does not require external high-precision resistors to set the float voltage, further saving cost and space.
Applications include industrial hand-held instruments, 12V to 24V automotive and heavy equipment applications, desktop cradle chargers and notebook or tablet computers.
The programmable switching frequency (200kHz to 1MHz) of the LT3651-4.2 enables the designer to balance solution size, power loss and filtering needs.
Synchronous operation enables charging efficiencies as high as 90 per cent.
Final float voltage accuracy is +0.5 per cent, charge current accuracy is +7.5 per cent and C/10 detection accuracy is +4 per cent.
Once charging is terminated, the LT3651-4.2 automatically enters a low current standby mode, which reduces the input supply current to 80uA.
In shutdown the input bias current is reduced to 15uA.
The LT3651-4.2 maximises battery life during all non-charging periods by draining <1ua data-blogger-escaped-battery.="" data-blogger-escaped-from="" data-blogger-escaped-the="">For safety and autonomous charge control, the device includes: automatic restart and preconditioning; a thermistor input for temperature-qualified charging; programmable input current limit; bad battery detection; and binary-coded status-output pins.
The LT3651-4.2 is available in a low-profile (0.75mm) 36-pin 5 x 6mm QFN package, and is offered in both E and I grade versions, guaranteed from -40C to 125C.
Pricing starts at $4.13 and $4.75 each, respectively, in 1,000-piece quantities.
Two-cell 8.2V and 8.4V options and a one-cell 4.1V version are planned for release within the next few months.
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Method prints onto aluminium or sheet-metal panels

Edited by the Electronicstalk editorial team Feb 28, 2011Elma Electronic has introduced a new digital printing method for painting front panels, which allows the kind of images, colours and possibilities that you would get from a paper digital printer.

The technology allows the aluminium or sheet-metal panels to accept very specific colours and images that were previously not possible.

Further, the cost for printing highly illustrative designs with multiple colours is the same as for just one colour.

In previous screening processes for front panels, each colour is a separate labour step and an additional cost.

Elma's digital printing enables customers to use more colours within their existing budgets and price points.

Another benefit of the Elma digital printing process is the detail and quality it provides.

Fine images, logos or text can be faded or lost with traditional silk-screening.

The digital process from Elma provides such precision that even very small text and fine detail of a logo comes through clearly.

Further, customers can now apply special gradients, shadows and other effects that were not feasible until now.

As just one process is required for digital printing, even the most elaborate designs save time and reduce costs.

In addition, the simplified process helps to improve quality and reliability, while reducing mistakes.

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Electronics enclosure provides dust-tight seal

Edited by the Electronicstalk editorial team Feb 28, 2011Schroff now offers a range of NEMA Type 9 enclosures, which are designed for housing electronic or electrical equipment in locations that are hazardous due to the presence of combustible dusts.

Manufactured by Hoffman, one of Schroff's sister companies within the Pentair Technical Products group, these robust enclosures are constructed from 5mm, 6mm and 10mm steel plate, with an ANSI grey polyester powder-coat finish.

Fibre gaskets, attached to the covers using mechanical retainers, ensure that the enclosures provide a dust-tight seal and prevent the ingress of combustible particulates.

Available in a choice of 14 different sizes with internal dimensions ranging from 203 x 152 x 102mm to 1,219 x 914 x 305mm, the NEMA Type 9 enclosures incorporate mounting brackets and either weldnuts or collar studs to support the optional internal panels.

The larger models are equipped with heavy-duty cover hinges.

In addition to the panels and panel support kits, other accessories include terminal block kits and industrial corrosion inhibitors.

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ICs capable of protecting multiple USB ports

Edited by the Electronicstalk editorial team Feb 28, 2011Intersil has introduced a range of power controllers designed to meet the power supply requirements of industry-standard USB devices, which offer high-current capability in a small package.

The ISL6185 and ISL6186 provide port power for products based on the USB 2.0 and 3.0 interface standards, offering designers several current-limit-level options, all with an accuracy 3x better than competitive solutions.

This results in more precise protection and increased design flexibility for today's USB power designs.

In addition, the ISL6185 and ISL6186 come in industry standard packages for easy, drop-in replacement as well as a new, smaller packages for saving more board space.

The ISL6185 independently controls two power channels and features a pair of 71 milliohm P-channel power switches.

Providing added design flexibility, each power channel is capable of protecting multiple USB ports.

The ISL6185 provides continuous current at 0.6, 1.1, 1.5 and 1.8A levels.

Its high current-limit capability supports USB 3.0 as well as USB 2.0.

In addition, both devices feature automatic restart/retry after an over-current or transient event, ensuring continued operation without requiring additional monitoring.

No user or system intervention is required to reset the devices, with automatic recovery when the load fault is cleared.

The ISL6186 USB power controller provides single channel over-current (OC) fault protection totaling up to 3.6A, allowing a single device to protect multiple USB ports.

The device features a 45 milliohm P-channel MOSFET power switch for power control and continuous current options for 1.5, 3 and 3.6A.

It also includes a Power Good output capability that provides supply status with no need for external components.

The range consists of eight individual functional product variants and three package options.

It is rated for a nominal 2.5 to 5V range and specified over full commercial and industrial temperature ranges.

Each device also features internal current monitoring, accurate current limiting, reverse bias protection and current limited delay to turn-off for system supply protection, along with control and communication I/O.

Off-state supply current is 1mA.

The ISL6185/6 range is provided with enable polarity options in an industry standard eight-pin SOIC pinout along with two versions in the 70 percent smaller 3x3 DFN.

The eight-pin DFN package offers the same performance as the eight-pin SOIC; the 10-pin DFN offers higher current capability in a very small package because of lower electrical and thermal resistance.

Prices start at $0.75 each in 1,000-piece units.

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Enhanced sensor connector seals to IP67 rating

Edited by the Electronicstalk editorial team Feb 28, 2011Binder-USA, has improved its M8 over-moulded sensor connector by adding a knurled and hex locking nut, which allows the connector to be tightened with a torque wrench to ensure proper mating.

The M8 overmolded connectors have three, four or six gold-plated contacts and are capable of handling up to 60V and up to 4A per contact.

When properly mated, the M8 over-moulded connectors are sealed to an IP67 rating.

The male and female cord sets are available in two and five-meter lengths.

Mating receptacles and field-attachable cable connectors are also offered, for a complete connecting system.

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High-density card socket saves PCB space

Edited by the Electronicstalk editorial team Feb 28, 2011Samtec has introduced a high-density socket featuring a bi-level mating design comprising two levels of contacts on a staggered 1mm centreline, which creates a card-effective 0.5mm pitch.

The Edge Rate High Density Edge Card Socket (BEC5 Series) is available with up to 140 I/Os in a 1 x 1.27mm-grid PCB pad layout, with four rows of contacts.

This system is suitable for high-speed applications benefiting from its rugged Edge Rate contacts, which are designed for superior impedance control and reduced broadside coupling with increased durability and cycle life.

The 0.5mm pitch high-density socket accepts standard 1.60mm' and 2.40mm-thick cards.

Additional features include weld tabs, alignment pins and lead-free solder charge terminations for easy board processing.

Tin-lead solder charges, as well as alternative platings and pin counts, are also available.

In addition to the new BEC5 Series 0.5mm pitch high-density system, Samtec's full line of High Speed Edge Rate Edge Card Sockets includes 0.8mm (HSEC8 Series) pitch in surface-mount and edge-mount designs for parallel, perpendicular and planar-board mating as well as a right-angle dual-stacking design (DSEC Series).

Stamped contact design sockets are also available in 0.635mm (MEC6 Series), 1mm (MEC1 Series), 1,27mm (MECF Series) and 2mm (MEC2 Series) pitches for edge-mount, right-angle and vertical applications.

Pricing on the BEC5 is approximately $0.10 per mated line.

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Photocoupler suits extreme ambient temperatures

Edited by the Electronicstalk editorial team Feb 28, 2011Toshiba Electronics Europe (TEE) has launched the TLP708, an ultra-compact, high-speed inverter-type photocoupler suitable for home appliances, induction heating equipment and factory automation.

The photocoupler features extended temperature performance while complying with the reinforced isolation class requirements of international safety standards.

Performance is guaranteed at temperatures from -40C to 125C.

Comprising a GaAlAs LED that is optically coupled to an integrated, high-gain, high-speed photodetector, the TLP708 is supplied in a six-pin SDIP (shrink DIP) package requiring just half the board mounting area of an equivalent eight-pin DIP device.

Despite its small size, the photocoupler has a minimum isolation voltage rating of 5,000Vrms.

Toshiba's new photocoupler operates with a maximum switching time of just 75ns, allowing it to support typical data-transfer rates of 15Mbit/s.

The integrated photodetector has an open-collector output stage and an internal Faraday shield that provides a guaranteed common-mode transient immunity of +/-15kV/us.

The TLP708 has dimensions of just 9.7 x 4.6 x 4.0mm.

Toshiba also offers a version with extended creepage and clearance distances, which has a board mounting footprint of 11.7 x 4.6mm.

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Touch-screen controller works with gloved hands

Edited by the Electronicstalk editorial team Feb 28, 2011At Mobile World Congress 2011, Maxim Integrated Products is demonstrating Max11855 and Max11871, projected capacitive touch-screen controllers offering four-point and 10-point touch detection.

Building on the company's reputation for differentiated analogue and mixed-signal performance, Maxim's Tactouch family of capacitive touch-screen controllers addresses the various performance and price points demanded by OEMs.

Maxim Integrated Products is demonstrating MAX11855 and MAX11871, projected capacitive touch-screen controllers

The latest Tactouch products offer superior sensitivity and noise immunity, making them the only devices capable of touch detection from a ballpoint/stylus and gloved hands.

These capabilities will enable a range of new user-interface experiences on handsets, tablets and other end equipment.

The Max11871 is a mutual capacitance touch-screen controller capable of detecting and tracking up to 10-finger simultaneous touch.

All processing is included on-chip to output up to 10 X,Y touch location coordinates, with a Z pressure metric associated to each touch point, via a standard I2C interface to a host microcontroller.

The part's analogue front-end provides near 60dB signal-to-noise ratio (SNR) performance, equivalent to a 1000:1 ratio between touch and no-touch.

This is an order of magnitude 10x higher than other solutions on the market today.

The SNR enables detection of very weak (in the femto-farad range) touch variations, such as from a hand waving near the screen (proximity detection), touch from a fine-tip stylus or ballpoint pen, or a hand covered by a glove.

Also, it means that the touch point can be farther away from the sensor, enabling touch screens to have thicker cover glass or plastic for improved ruggedness.

The Max11871 also includes a proprietary architecture to reject noise (by over 40dB) from external sources such as AC USB chargers, LCDs, or CFL lights with no additional external components.

This selectivity enables the part to be used in high LCD noise environments such as next-generation on-cell and in-cell touch screens.

For applications only requiring four-point touch detection, the Max11855 and Max11856 implement a four-finger simultaneous mutual capacitive multi-touch solution, which eliminates any ghosting effect.

As part of Maxim's Tactouch product line of haptics and touch-screen controllers, the Max11871 and Max11855/Max11856 can directly interface to the previously introduced Max11835/Max11836 haptic controllers/drivers for piezo actuators and electro-active polymers.

These high-voltage actuators mimic the feeling of a button click on a touch screen.

The Max11871 comes in a 6 x 6mm 48-pin TQFN package with 32 cap-sense channels.

A wafer-level package (WLP) option is planned for designs requiring an ultra-small footprint.

The Max11855 comes in a 5 x 5mm 40-pin TQFN package with 25 cap-sense channels, typically sufficient for panels up to 4in.

The Max11856 provides 31 cap-sense channels in a 6 x 6mm 48-pin TQFN package, making it suitable for panels up to 7in depending on required touch accuracy.

With on-chip clock oscillator and voltage references, all parts only require a few passives as external BOM.

All parts are sampling now for qualified opportunities and mass production is scheduled to begin before the end of 2011's first quarter.

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Tyco launches Type LS solder-less LED socket

Edited by the Electronicstalk editorial team Feb 28, 2011Tyco Electronics (TE), a provider of engineered electronic components, has launched the Type LS solder-less LED socket, designed specifically for use with the new Philips Lumileds Luxeon S LED.

Debuting at Strategies in Light 2011 in Santa Clara, California, the product offers a solder-less termination that complements this newly released lighting-class LED by Philips Lumileds.

The Type LS socket complies with UL-1977 specifications and is designed with insulation displacement technology to simplify the termination of 24 AWG wires to the socket.

An integral stainless steel spring within the socket ensures that uniform and adequate normal force is applied to the LED for optimum thermal performance.

In addition, the product simplifies the positioning of the Luxeon S LED on a heat sink by utilising a locator - a plastic frame that is first placed on the heat sink to correctly orient the LED in its position prior to socket attachment.

Once positioned, only three commercially available #4 or M3 screws are needed to rapidly secure the socket to the heat sink.

Designed to maximise optical efficiency in un-lensed applications, the shape of the Type LS socket ensures that 98 per cent of the light emitted from the LED is unobstructed.

Offered both with and without optics snap features, it provides flexibility for fixture designers by providing features for a secondary optic attachment.

For optical flexibility, the matching Venla series of reflectors is offered by Ledil Oy in a variety of beam angles and provides a simple snap-fit to the socket.

Visitors to Booth 400 at Strategies in Light 2011 can learn more about the new solder-less LED socket, as well as TE's SSL range of products.

Customer drawings, 3D-model files and application specifications are available via the company's website.

Production will begin in late March 2011.

The TE Type LS socket, Luxeon S LED and Ledil reflectors and associated driver solutions will also be stocked and available through Future Lighting Solutions.

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Compact optical sensor ICs suit portable systems

Edited by the Electronicstalk editorial team Feb 28, 2011At Mobile World Congress 2011, Maxim Integrated Products is introducing the Max44007/Max44009, digital ambient-light sensor (ALS) ICs with an adaptive-gain block, suitable for smartphones and TVs.

Designed using the company's proprietary BiCMOS technology, these ICs integrate two optical sensors, an ADC and digital functionality into a tiny 2x 2 x 0.6mm package.

Maxim Integrated Products is introducing the MAX44007/MAX44009, digital ambient-light sensor ICs

This integration saves valuable board space while delivering the industry's highest performance.

The Max44007/Max44009 are suitable for applications such as tablet and notebook PCs, smartphones, TVs, digital lighting-management systems and light-intensity monitoring applications.

According to Maxim, the ICs consume 100x less power than the nearest competitive product, significantly extending battery life.

They offer a unique interrupt function that constantly measures the amount of light and reports to the microcontroller when the measurement passes the threshold.

This functionality extends power savings by reducing the frequency of I2C communications.

In addition to providing precise light measurement, the digital communication of Maxim's light sensors is immune to parasitics on the communication interface.

Maxim's BiCMOS technology enables the integration of two photodiodes along with an optical filter to reject ultraviolet and infrared light.

This allows the Max44007/Max44009 to replicate the optical response of the human eye and accurately measure visible light in a variety of environmental settings.

Advanced algorithms correct for any spectra variations between light sources, ensuring an accurate lux response.

Moreover, the ADC integration time of the sensors can be adjusted from 6.25ms to 800ms.

A default integration time of 100ms ensures excellent 50Hz/60Hz rejection.

Hand-held devices frequently employ tinted or black glass on top of the sensor, which creates challenges for the light sensor, since black glass shifts the response to various light sources.

The Max44007 provides access to two different optical sensors: a visible-plus-infrared photodiode and an infrared photodiode.

Once the designer knows the response of the black glass, it can be factored into the light sensor's measurement for superior accuracy and sensitivity (down to 0.025 lux).

Ambient-light sensors require the widest dynamic range possible to support a broad spectrum of light conditions, from direct sunlight to complete darkness with every variation in between.

Even in digital light sensors, the gain has to be set to a certain value to address different modes of operation in multiple light scenarios.

This added configuration requirement increases both design complexity and time to market.

The Max44007/Max44009 feature an integrated adaptive-gain block that automatically selects the optimum gain range.

This capability relieves designers of having to manually programme the device and also offloads work from the application processor or microcontroller.

Additionally, it provides a wide dynamic range.

The Max44009 can measure light levels from 0.045 lux to 188,000 lux, yielding a dynamic range of more than 4,000,000 to one.

Designed to meet tight power budgets, the ICs boast an operating current of 0.65uA, which is lower than the power-down current of many competitive products.

Furthermore, they operate from an industry-low 1.7V to 3.6V supply voltage.

Consuming as little as 1.1uW of operating power, Maxim's solutions use 100x less power than the nearest competitor.

As an added benefit, the devices' low supply voltage allows them to use the same 1.8V supply for both the supply voltage and the I2C interface.

This reduces power consumption and design complexity by only requiring a single voltage rail for the part.

An address pin allows the use of two sensors on the same I2C bus.

Designed for the tight space requirements of portable systems, the Max44007/Max44009 are offered in a lead-free, 2 x 2 x 0.6mm, six-pin UTDFN-Opto-EP package.

Prices start at $1.20 (?0.74) for quantities of 1,000-up, FOB USA.

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Rugged spring pins suit cable assemblies

Edited by the Electronicstalk editorial team Feb 28, 2011The Mill-Max 0850, 0851, 0852 and 0853 spring pins are capable of carrying 9A continuous current at a 10C temperature rise and suitable for use in circuits operating at currents above signal level.

Applications include board stacking, docking stations, cable assemblies, quick connects and anywhere there is a blind-mate situation.

These large-scale spring pins feature a gold-plated stainless-steel spring, .050in diameter solid plunger and thick wall construction to withstand the rigours of demanding applications.

The 085X series is characterised by a greater mass and surface area which provides a lower resistance electrical path than miniature spring pins.

Because they are designed and built with the same precision of our miniature spring pins they exhibit excellent signal integrity in shock and vibration environments.

Designed for through-hole mounting, each pin has a large diameter post and flange providing for a perpendicular and secure PCB attachment.

The 085X series provides a generous .045in mid-stroke and .090in maximum stroke allowing for use in applications where stack-up tolerances are great.

Rated at 1,000,000 cycles minimum, the Mill-Max 085X series spring pins are the best choice for higher-current, high-reliability spring pin requirements.

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