LED Drivers

Synchronous step-down LED driver delivers over 20A of continuous LED current

Linear Technology has just announced the LT3743, a synchronous step-down DC/DC converter designed to deliver constant current to drive high current LEDs. The device’s 5.5V to 36V input voltage range makes it ideal for a wide variety of applications, including industrial, DLP projection and architectural lighting.

Full-Featured LED Controller Delivers over 80 Watts of LED Power

The LT3743 provides up to 20A of continuous LED current from a nominal 12V input, delivering in excess of 80 Watts. In pulsed LED applications, it can deliver up to 40A of LED current or 160 Watts from a 12V input. Efficiencies as high as 95% eliminate any need for external heat sinking and significantly simplify the thermal design. A frequency adjust pin enables the user to program the frequency between 100kHz and 1MHz so designers can optimize efficiency while minimizing external component size. Combined with a 4mm x 5mm QFN or thermally enhanced TSSOP-28 package, the LT3743 offers a very compact high-power LED driver solution.

The LT3743 offers both PWM and CTRL_SELECT dimming, offering 3,000:1 dimming capability at three LED current levels, making it ideal for color mixing applications such as those required in DLP projectors. Similarly, the LT3743’s unique topology enables it to transition between two regulated LED current levels in less than 2µsec, enabling more accurate color mixing in RGB applications. LED current accuracy of ±6% is maintained in order to ensure the most accurate luminosity of light from the LED. Additional features include output voltage regulation, open-LED protection, overcurrent protection and a thermal derating circuit.

The LT3743EUFD is available in a 28-pin 4mm x 5mm QFN package, whereas the LT3743EFE is available in a thermally enhanced TSSOP-28. Pricing starts at $4.80 and $4.95 each, respectively in 1,000-piece quantities. Extended temperature versions, or “I” grades, namely the LT3743IUFD and LT3743IFE are also available. Pricing starts at $5.65 and $5.82 each respectively in 1,000-piece quantities.

Nanoresearch

Next-generation wireless ECG patch drives joint research activity
Terepac and IMEC join forces in low-cost flexible electronics packaging

Terepac Corporation and IMEC, the European research center in nanotechnology, have announced their collaboration on novel packaging technologies for flexible electronics. The initial driver for this synergistic shared research relationship is a next generation wireless ECG system, developed in the Human++ Program at Holst Centre, Eindhoven (NL).

As electronic systems become ubiquitous, the demand for innovative packaging technologies increases. For many applications, like on-the-body devices, thin and flexible form factors greatly improve the comfort of the wearer. In order to allow large-scale manufacturing and market penetration, low-cost yet high value solutions are key. Traditional electronics packaging and assembly with rigid printed circuit boards and pick-and-place machines are unable to cope with these demands.

The technology developed by Terepac holds great promise to give a unique answer to the challenges mentioned above. In its patented photochemical printing process, thinned silicon dies and passive components can be placed on flexible substrates at speeds of more than one chip per second and with accuracies down to a few microns.

The wireless ECG patch that is being developed in IMEC's Human++ program at Holst Centre, an open-innovation initiative by IMEC and TNO, will be used as a test vehicle for further development of Terepac's technology. For IMEC it is an opportunity to go from a lab-scale assembly on polyimide carrier to a more production-ready version of its wireless sensor nodes. First results are expected by mid 2010.

Ric Asselstine, CEO of Terepac: "Following five years of development by a team of world-class scientists and engineers and based on the patents of co-founder and CTO Dr Jayna Sheats, Terepac is ready to completely transform the landscape of small form factor electronic packaging. The company aims to become a total solutions provider able to collaborate with companies up- and downstream in the value chain. Apart from being on the forefront of technological innovation, being able to tap into the existing partner network of IMEC and Holst Centre is a great asset to our collaboration."

Julien Penders, Program Manager Body Area Networks at IMEC/Holst Centre: "Initial contacts with Terepac were laid a few months ago. It quickly became clear that their expertise would be a valuable addition to the existing competences that we and our partners have on board. We look forward to further developing our sensor technology and opening doors towards low-cost and large-scale manufacturing for our existing partners or companies interested in this technology."

Steam flow

Flow meters for steam flow
Vortex flow meters are ideal for high accuracy measurements of non-condensing and saturated steam flow.


Racine Vortex has released their RNS Series (Insertion) and RWS Series (Wafer) Vortex Steam Flow Meters. The meters are suitable for measuring non-condensing steam and saturated process steam at pressures up to 150 psi. Leading applications include boiler monitoring and other energy-related uses, as well as building and facilities management.

Both the RNS and RWS series meters have no moving parts and are virtually maintenance-free. All meters in both series are loop-powered devices with standard HART communication for ease of field programming and system integration.

Both meters work in operating temperatures of -20 to 366°F. An internal RTD and an optional external pressure sensor provide data to the internal flow meter software, which compensates for changes in temperature and pressure to achieve an accurate flow measurement. Accuracy of both meters is ±1% of reading, with repeatability of 0.5%. The RNS and RWS meters are pre-calibrated for specific uses, and can be rescaled in the field with the use of the provided PC-based software program.

The RNS Series insertion flow meter is available for pipe sizes from 6 to 72 inches (152 to 1829 mm), has a 35:1 turndown ratio, and can be configured for mass flow measurements.

The RWS Wafer meter has 316SS wetted parts, an extremely small bluff bar for little or no pressure drop, and NIST-traceable calibration. It is available in five sizes for flange mounting in pipes from 1/2 to 4 inches.

Options for both meters include ATEX certification, a two-line eight-digit rate/totaliser display, and remote electronics.

New brochure for contactless rotary sensors

Penny + Giles, has announced a new SRH Contactless Rotary Sensors brochure.

Complete with technical information, including a selection guide for ordering the various models and features, the free brochure is available in print and online. It is user-friendly and offers information about the five models in the range, from single output 28mm compact to rugged 87.5mm dual output versions for position feedback of critical functions in a wide range of industrial applications.

The brochure includes detailed ordering codes that allow a wide range of factory programmable options for these contactless rotary sensors that use the latest 12bit Hall effect sensing technology.

The brochure is an essential resource for designers specifying rotary position sensors for functions in a wide range of markets, from motor racing to off-highway vehicles and industrial process control.

Couplers approved

Device Couplers
receive three major FM approvals

The TRUNKSAFE TS200 Fault-Tolerant Fieldbus System from MooreHawke, the fieldbus division of Moore Industries, has received three major certifications through Factory Mutual (FM).

This system provides a cost-effective and highly reliable strategy to maintain continuous communications between field devices and a host system in the event of any single point failure (such as any open single wire) on a FOUNDATION Fieldbus H1 or PROFIBUS PA segment.

TRUNKSAFE device coupler series, including models TS206 and TS20W, has acquired ATEX-Type N, IECEx-Type N, and cFMus-General/Ordinary Location and Non-Incendive certifications from Factory Mutual.

“TRUNKSAFE is the industry’s first fault-tolerant fieldbus system intended for use in both critical and non-critical processes. Now, customers with hazardous location process segments can have complete confidence in TRUNKSAFE’s capabilities to protect their process,” said Moore Industries Director of Engineering Tina Lockhart.

Copies of the ATEX, IECEx and cFMus certificates can be downloaded from Moore Industries Interface Solution Product Certification Summary, a downloadable PDF listing of product certifications. The alphabetical listing is by product, and contains links to copies of product certificates available. To download the full FM certificates, visit the online Interface Solution Product Certification Summary.

Gas emission

Hired emissions analyser checks gas rig in Burma

Following the installation of a turbine on a natural gas rig off the coast of Burma, it was necessary for Siemens Industrial Turbomachinery (SITL) to analyse emissions from the turbine and a hired Testo 350 XL emissions analyser from Ashtead Technology proved ideal for the application.

Based in Lincoln (GB), SITL designs, manufactures, installs and provides life time support for gas turbines used in industrial power generation and the oil and gas industry.

Guy Simpson, Group Leader (Performance), explained that the Testo 350 was required to monitor levels of Nitric Oxide (NO) Nitrogen Dioxide (NO2), Carbon Monoxide (CO), Oxygen (O2) and temperature on behalf of the client.

He said: “I have spent two periods in Burma over the last 12 months, during which time one of the main targets was to ensure that emissions from the gas turbines were at acceptable levels. The acceptance criteria were set by our client in line with their own global environmental standards. In this instance, we needed to monitor emissions from the exhausts of the two gas turbines.

“When it came to deciding how we would measure the emissions, we contacted Ashtead Technology because we knew that renting would be a more affordable option as opposed to buying monitoring instrumentation in the UK or Asia. We discovered that another benefit of renting was that the instrumentation arrived fully calibrated and ready to use. In addition, the technical advice we received from Ashtead before the project started was extremely useful.”

Employing smart sensor technology, the handheld Testo 350 provides compliance level accuracy. Battery powered with an internal datalogger and a built-in printer with touchscreen technology the instrument is ideal for applications that require portability. These include short-term industrial stack gas monitoring, combustion analysis and flue gas monitoring.

Alan Hasson, Ashtead Technology’s General Manager, added: “This application highlights the many benefits of renting emissions monitoring instrumentation, including significant cost savings and access to the very latest technology.”

Keypads

Robust alpha-numeric keypads for outdoor use
New two row waterproof keypad is vandal resistant

Foremost Electronics (click and listen to that English accent!) has introduced the AK-206 range of rugged metal keypads for outdoor applications.

The AK-206 keypads feature two rows of either numeric or alpha-numeric (telephone keypad) buttons and offer a robust, vandal resistant, waterproof switching solution for secure door-entry systems, industrial control, security and emergency systems.

Switch contacts are rated at 24VDC/20mA with contact resistance >200Ω and have an operating life of 2,000,000 cycles per key over an operating temperature range of -40 to +65ºC. The keys have a stroke length of 2.0mm and an actuating force of approximately 150gm.

Alan Cook, Managing Director of Foremost Electronics comments, “Our new AK-206 vandal-resistant keypads offer panel and system builders a rugged and reliable secure access or control solution. These new waterproof switches extend our wide range of conventional and specialist switch solutions and increase our value to our customers as a one-stop, specialist Emech product provider.”