Category Archives: LED Manufacturing

Aledia, a developer of LEDs-based on disruptive microwire GaN-on-Silicon technology, announced today that it has made its first LEDs on 8-inch (200mm) silicon wafers. The cost of Aledia’s LED 3D chips based on microwires is expected to be four times less than traditional planar (2D) LEDs. Additionally, Aledia announced its first-round financing totalling €10 million, or approximately $13M, with leading US and European investors, which was closed in 2012.

Aledia solves the important cost issue in the very large and growing LED market. The continued integration of LEDs into new applications, such as general lighting, depends on LEDs becoming available at substantially lower prices than today. Aledia’s microwire technology enables the steep cost reduction that is vital for the further transition to LED. The Aledia LED technology, made on large-size silicon wafers and with very low materials cost, represents a cost-disruptive solution to this problem. Furthermore the new LED technology is compatible with silicon CMOS technology and will be manufactured directly in existing high-volume silicon foundries.

“Since our financing last year, we have scaled up our microwire manufacturing process and transferred it to 8-inch (200mm) silicon wafers. We can now push forward to optimize the performance of these products and bring them to market,” indicated Giorgio Anania, Aledia co-founder, President and CEO.

Investors in Aledia’s first-round financing included Sofinnova Partners, a leading European venture capital fund and an active investor in energy; New-York based Braemar Energy Ventures, a leading US energy technology investor with various investments in the LED and illumination area; Demeter Partners, the largest France-based cleantech investor; and CEA Investissement, the venture capital arm of CEA, France’s Commissariat à l’Energie Atomique et aux Energies Alternatives.

“This is an innovative technology that can have a disruptive effect on the LED market,” said Jiong Ma, partner at Braemar Energy Ventures. “Braemar is committed to investing in companies like Aledia that have developed a breakthrough approach to LED lighting to accommodate a rapidly changing market. We are excited about the future opportunities this investment will bring and the expansion of Aledia’s market presence and product offerings.”

“We are proud to participate in the new venture of Giorgio Anania, a successful entrepreneur already well known to Sofinnova, and of an outstanding technical team, that could revolutionize the large and growing LED market, both in cost and performance,” added Alessio Beverina of Sofinnova Partners.

“We believe that the development of LED lighting is an important element of energy-efficiency in our economies – lighting representing approximately 20% of all electricity usage. A technology able to make a significant breakthrough in the cost-effectiveness of using LEDs and thereby accelerate their adoption will have a major environmental and financial impact,” concluded Sophie Paturle, partner at cleantech specialist Demeter Partners.

The 3D GaN-on-Silicon microwire technology was developed over a six year period at the LETI-CEA in Grenoble, France. As part of its spin-out from CEA, Aledia received exclusive worldwide rights to all present and future CEA patents on microwire technology as applied to the area of lighting. Several additional patents have already been filed directly by Aledia.

Crystal IS, Inc., a manufacturer of proprietary, high-performance ultraviolet light emitting diodes (UVC LEDs) for monitoring, purification, and disinfection applications, has announced today that they achieved more than 65mW in optical output at 260nm from a single UVC LED operated in a continuous mode. The details of this breakthrough were recently published in Applied Physics Express.

"This achievement is a technological milestone in the continued development of brighter, more efficient and reliable UVC LEDs. By employing die thinning and encapsulation techniques, we were able to increase the photon extraction efficiency to over 15%, “said Leo Schowalter, founder and CTO.  "By fabricating our LEDs on our home grown aluminum nitride substrates, we continue to set the pace of what is possible for the combination of highest efficiencies and longest lifetimes in the 250-280nm wavelength range, far surpassing diodes fabricated on sapphire."

“This R&D accomplishment represents a more than six-fold increase in performance from just one year ago,” said Larry Felton, CEO. “Our progress in business operations continues on a like pace, readying us and our LEDs for commercial success.”

UVC refers to ultraviolet light with wavelengths between 200 – 280 nanometers (nm). Light in the UVC wavelength can be used for disinfecting water, sterilizing surfaces, destroying harmful micro-organisms in food products and in air, and for spectroscopy applications. Yole Développement estimates the UVC lamp market to be nearly $200 Million in 2012, with lamps being replaced increasingly by UV LEDs.

"Our products will address some of the most pressing health concerns of our time,” said Therese Jordan, Senior Vice President of Business Development. “We are seeing demand in both water and air for the disinfection and quality monitoring aspects of UVC. Similarly, spectroscopic instruments are also taking advantage of the high light output available in a UVC LED. Unlike UV lamps, UVC LEDs are mercury-free, compact, rugged and robust, lending themselves to an array of designs and hold the promise of long life and environmentally friendly end-of-life disposal.”

Engineering samples of UVC LEDs are available from Crystal IS.

UVC LED from Crystal IS

Samsung Electronics catapulted to the top of the optoelectronics supplier ranking in 2012 from 12th place in 2011 after it gained full ownership of Samsung LED, a 50-50 joint venture in light-emitting diodes that was created in 2009 between Samsung Electronics and affiliate Samsung Electro-Mechanics.  In April 2012, the venture was absorbed into Samsung Electronics to strengthen and expand the use of high-brightness LEDs in displays, LCD TVs, and new solid-state lighting products. This transfer increased Samsung’s optoelectronics sales by 223% to $2.5 billion in 2012 compared to $780 million in 2011, according to the new 2013 edition of IC Insights’ O-S-D Report—A Market Analysis and Forecast for Optoelectronics, Sensors/Actuators, and Discretes.

The LED operation added $1.5 billion to Samsung’s total revenues in 2012, based on the O-S-D supplier rankings in the new 350-page report, which becomes available in March 2013.  The rest of Samsung’s optoelectronics sales come from CMOS image sensors, which generated $975 million in 2012—a 25% increase from 2011.  The 2013 O-S-D Report shows Samsung as the second-largest supplier of CMOS image sensors in 2012, positioned between top-ranked OmniVision and third-place Sony.  The 2013 O-S-D Report provides top 10 supplier rankings for the individual optoelectronics, sensors/actuators, and discrete semiconductor markets in addition to an overall top 30 list of companies selling O-S-D products in 2012.

Samsung’s huge increase in optoelectronics sales vaulted it to first place in IC Insights’ top 30 O-S-D ranking for 2012 from 20th in 2011. High-brightness white LED and blue-laser pioneer Nichia in Japan moved up to second place in the O-S-D ranking from fourth place in 2011 with an 11% increase in optoelectronics sales in 2012.  In the 2012 O-S-D ranking, Toshiba and ST fell to third and fourth, respectively, due to steep sales declines in CMOS image sensors and double-digit drops in discretes.  Toshiba and ST had been the No. 1 and No. 2 suppliers in the O-S-D marketplace since the middle of the last decade.

top five O-S-D suppliers 2012

Suppliers of high-brightness LEDs generally moved higher in the overall O-S-D ranking in 2012 due to strong sales growth in lamp devices used for solid-state lighting systems.  In addition to Samsung and Nichia moving up to the No. 1 and 2 positions in O-S-D, six other LED makers climbed higher in the top 30 ranking (Sharp, Osram, Philips, LG Innotek, Seoul Semiconductor, and Toyoda Gosei). U.S.-based Cree, which makes LEDs and radio-frequency/microwave power transistors, was unchanged in the top 30 O-S-D ranking at 17th place in 2012.

Among the significant changes in the O-S-D supplier rankings was ST climbing to first place in the sensors/actuators market in 2012 from fourth in 2011.  ST’s sensor sales grew 19% in 2012 to $791 million.  Hewlett-Packard fell to fourth place in sensors/actuators last year from the top spot in 2011 due to a 10% decline in sales of HP’s inkjet-printer actuators in 2012.  In discrete semiconductors, Toshiba held on to its top position despite a 12% decline in discretes sales in 2012.

Oxford Instruments Plasma Technology has just announced an evolution in batch etch technology with the launch of the PlasmaPro 1000 Astrea etch system, a large batch etch solution for PSS, GaN and AlGaInP that will offer HBLED production manufacturers high throughput. The launch is being made at the LED China exhibition in Shanghai this week, where Dr. Mark Dineen, Oxford Instruments HBLED Product Manager will present the new system to the LED China Conference delegates.

“The PlasmaPro1000 Astrea is our ultimate batch etch tool, building on over fifteen years experience as a major supplier to the HBLED industry,” says Dr. Mark Dineen, Oxford Instruments Plasma Technology’s HBLED Product Manager. “Today’s HBLED manufacturers justifiably demand high yield, high throughput, optimum device quality and low cost of ownership.  Our PlasmaPro1000 Astrea large batch etch system offers solutions for all of these.”

With wafer batch sizes from 55 x 2” to 3 x 8”, the system has been designed specifically for the harsh chemistries required for HBLED materials. The PlasmaPro1000 Astrea delivers low damage, high yield processes ensuring the maximum light output from customers’ chips.  This is a highly configurable system, with process chambers that are available as standalone modules or in cluster configurations, available on a four sided cluster tool capable of supporting up to three process modules.

Designed to ensure high system availability and ease of serviceability, key system features and benefits include:

• >690mm large area source for highly uniform plasma

• 490mm electrode giving unparalleled throughput from batch sizes of 55×2”, 14×4”, 7×6” and 3×8”

• High conductance pumping system

• Dual entry gas inlet for ease of process tuning

• Maximized clamping for wafer cooling

• Z-movement electrode for ultimate uniformity

• Reliable hardware and ease of serviceability for excellent uptime

“This advanced and innovative system has been developed to address the exacting needs of HBLED Production users, who demand not only the very latest technological innovations, but also the superb customer support offered by our company,” Dan Ayres, Managing Director of Oxford Instruments Plasma Technology said.

Cree, Inc. announces the release of its second generation SiC MOSFET, enabling systems to have higher efficiency and smaller size at cost parity with silicon-based solutions. These new 1200V MOSFETs deliver power density and switching efficiency at half the cost per amp of Cree’s previous generation MOSFETs. At this price-performance point, they enable lower system costs for OEMs and provide additional savings to the end-user through increased efficiency and lower installation costs due to the lower size and weight of SiC-based systems.

“We have evaluated Cree’s second generation SiC MOSFET in our advanced solar circuits,” stated Prof. Dr. Bruno Burger, renowned industry expert at the Fraunhofer-Institute in Freiburg, Germany.  “They have state-of-the-art efficiency and enable system operation at higher switching frequencies that result in smaller passive components, especially smaller inductors. This substantially improves the cost-performance tradeoff in solar inverters in favor of smaller, lighter and more efficient systems.”

The superior performance of these new SiC MOSFETs enables the reduction of required current rating by 50-70% in some high power applications.  When properly optimized, customers can now get the performance benefits of SiC with the same or lower systems cost as with previous silicon solutions.  For solar inverters and uninterruptible power supply (UPS) systems, the efficiency improvement is accompanied by size and weight reductions.  In motor drive applications, the power density can be more than doubled while increasing efficiency and providing up to twice the maximum torque of similarly rated silicon solutions.  The product offering range has been extended to include a much larger 25 mOhm die aimed at the higher power module market for power levels above 30 kW. The 80 mOhm device is intended as a lower cost, higher performance upgrade to the first generation MOSFET.

“With our new MOSFET platform, we already have design wins in multiple segments,” explained Cengiz Balkas, vice president and general manager, Cree Power and RF.  “Due to the rapid acceptance of this second generation of SiC MOSFETs, we are shipping pre-production volumes to several customers ahead of schedule and we are ramping volume production in-line with customer demand.”

Die are available with ratings of 25 mOhms, intended as a 50 amp building block for high power modules, and 80 mOhm.  The 80 mOhm MOSFET in a TO-247 package is intended as a higher performance, lower cost replacement for Cree’s first-generation CMF20120D. Packaged parts are available immediately from DigiKey, Mouser and Farnell. 

Yole Développement announced today its new report “UV LEDs: Technology & Application Trends” which presents UV LED new applications and associated market metrics for the period 2012-2020, and a deep analysis of UV LED technology and UV LED lighting industry.

Thanks to UV curing, UV LEDs should become a $270M business by 2017, and could hit $300M if new applications boom

Thanks to its compactness, low cost of ownership and environmentally-friendly composition, UV LED continues to replace incumbent technologies like mercury. Hence, the UV LED business is expected to grow from $45M in 2012 to nearly $270M by 2017, at a CAGR of 43% — whereas the traditional UV lamps market will grow at a CAGR of 10% during the same time period.

In 2012, UVA/UVB applications represented 89% of the overall UV LED market. Amongst these applications, UV curing is the most dynamic and most important market, due to significant advantages offered over traditional technologies (lower cost of ownership, system miniaturization, etc.). This trend is reinforced by the whole supply chain, which is pushing for the technology’s adoption: from UV LED module and system manufacturers to ink formulators and (of course) the associations created to promote the technology. And with Heraeus Noblelight’s recent acquisition of Fusion UV (Jan. 2013), all major UV curing system manufacturers are now involved in the UV LED technology transition.

Concerning UVC applications, they are still in their infancy and their sales are mainly for R&D purposes and analytic instruments like spectrophotometers. But given some newly published results (increase of EQE over 10%, etc.) and the recent commercialization of the world’s first UVC LED-based disinfection system (2012), the market should kick into gear within the next two years.

In addition to traditional applications (UV lamps replacement), and due to their unique properties (compactness, higher lifetime, robustness, etc.), UV LEDs are also creating new applications that aren’t accessible to traditional UV lamps, i.e. apps that are miniaturized and portable.

“In 2012, several new UV LED based products were launched, including cell phone disinfection systems, nail gel curing systems and miniaturized counterfeit money detectors – and this is likely to continue!” explains announced Pars Mukish, Technology & Market Analyst, LED, at Yole Développement. “We estimate that if new UV LED applications continue emerging, the associated business could represent nearly $30M by 2017, which would increase the overall UV LED market size to nearly $300M,” he adds.

This market and technology analysis is a comprehensive review of every UV application (including a deep analysis of UV curing and UV disinfection purification), highlighting: UV working principle, market structure, UV LED market drivers and the challenges/characteristics associated, time-to-market, penetration rate & Total Accessible Market (TAM) for UV LEDs, and much more. Additionally, Yole Développement details the market metrics for traditional UV lamps and UV LEDs over the period 2012 – 2017, with splits by application for each technology (volume & market size, etc.).

The report also presents an analysis of emerging UV LED applications, detailing: short-term applications that have already begun emerging, UV LED Concept Knowledge theory, and more.

Once UVC LED performance is sufficient, the supply chain battle will intensify

The booming UVA/UVB market (mostly UV curing) has attracted several new players from different backgrounds over the past few years: traditional UV lamp suppliers, traditional UV system suppliers, pure UV LED system suppliers, and others. Each player employs a different strategy for capturing the maximum value created by this disruptive technology: horizontal integration (from UV lamp to UV LED), vertical integration (from UV LED device to UV LED system and vice-versa) or both (from UV lamp to UV LED system). We should point out that traditional UV lamp manufacturers are under the most pressure since they have to compensate for the waning lamp replacement market by diversifying their activities in higher supply chain levels.

In the end, every UV LED device/system manufacturer faces the same technical issues when it comes to integrating UV LEDs into a system (thermal management, optics, etc.), but experience is gained with each passing year. Once UVC LEDs achieve sufficient performance, there’s no way a manufacturer will allow the opportunity to pass them by. When that moment comes, the whole supply chain will become a mess due to an increasingly competitive environment, and consolidation will be necessary. Yole Développement analysis covers the UV LED industry, detailing: main players & associated strategies/business models, 2012 industrial value & supply chains, key players’ revenue and market share, and much more.

Bulk AlN vs. AlN on sapphire template: no current winner

AlN on sapphire templates are definitely the substrate of choice for UVA applications, as they provide the right mix between cost and performance. However, for UVC applications (and some UVB applications) the competition with bulk AlN substrate is strong, since such material could allow for improvement at the device level in terms of lifetime, efficiency (IQE and EQE) and power output.

Right now, the debate is still on. And even if bulk AlN’s superior performance has been demonstrated by companies such as Crystal-IS and HexaTech, the associated cost (2.5x to 4x more compared to AlN on Sapphire template) still remains an obstacle to developing UVC LEDs at a reasonable price.

Indeed, such a situation has already occurred with GaN substrate for visible LEDs. Bulk GaN was the ideal technical candidate, but cost was too high and sapphire was widely adopted instead. Will UV LEDs meet the same fate?

In addition to substrate issues for UVC LED development, epitaxy represents another challenge for increasing device performance. Such barriers will have to be surpassed before we see commercialized UV LED-based disinfection/purification systems.

researcher Ma Ming developes brighter, smarter, more efficient LEDsRensselaer Polytechnic Institute student Ming Ma has developed a new method to manufacture light-emitting diodes (LEDs) that are brighter, more energy efficient, and have superior technical properties than those on the market today. His patent-pending invention holds the promise of hastening the global adoption of LEDs and reducing the overall cost and environmental impact of illuminating our homes and businesses.

For this innovation, Ma, a doctoral student in the Department of Materials Science and Engineering, has been named the winner of the prestigious 2013 $30,000 Lemelson-Rensselaer Student Prize. He is among the three 2013 $30,000 Lemelson-MIT Collegiate Student Prize winners announced today.

“For more than 175 years, Rensselaer has produced some of the world’s most successful engineers and scientists, explorers and scholars, innovators and entrepreneurs. Doctoral student Ming Ma, with his groundbreaking invention of GRIN LEDs, honors and continues this tradition of excellence,” said David Rosowsky, dean of the School of Engineering at Rensselaer. “Rensselaer and the School of Engineering offer a hearty congratulations to Ming for his achievement. We also applaud all of the winners, finalists, and entrants of the Lemelson-MIT Collegiate Student Prize for using their talent and passion to engineer a better world and a better tomorrow.”

Ma is the seventh recipient of the Lemelson-Rensselaer Student Prize. First given in 2007, the prize is awarded annually to a Rensselaer senior or graduate student who has created or improved a product or process, applied a technology in a new way, redesigned a system, or demonstrated remarkable inventiveness in other ways.

“Invention is critical to the U.S. economy. It is imperative we instill a passion for invention in today’s youth, while rewarding those who are inspiring role models,” said Joshua Schuler, executive director of the Lemelson-MIT Program. “This year’s Lemelson-MIT Collegiate Student Prize winners and finalists from the Massachusetts Institute of Technology, Rensselaer Polytechnic Institute, and the University of Illinois at Urbana-Champaign prove that inventions and inventive ideas have the power to impact countless individuals and entire industries for the better.”

Seeking Brighter, Smarter LEDs

Conventional incandescent and fluorescent light sources are increasingly being replaced by more energy-efficient, longer-lived, and environmentally friendlier LEDs, but LEDs still suffer from challenges related to brightness, efficiency, and performance  With his project, “Graded-refractive-index (GRIN) Structures for Brighter and Smarter Light-Emitting Diodes,” Ma faced these problems head-on and tackled a fundamental, well-known technical shortcoming of LED materials.

LEDs are hampered by low light-extraction efficiency—or the percentage of produced light that actually escapes from the LED chip. Currently, most unprocessed LEDs have a light-extraction efficiency of only 25 percent, which means 75 percent of light produced gets trapped within the device itself.

One solution that has emerged is to roughen the surface of LEDs, in order to create nanoscale gaps and valleys that enable more light to escape. While surface roughening leads to brighter and more efficient light emission, the roughening process creates random features on the LED’s surface that do not allow for a complete control over other critical device properties such as surface structure and refractive index.

Freeing Trapped Light with GRIN LEDs

Ma’s solution to this problem was to create an LED with well-structured features on the surface to minimize the amount of light that gets reflected back into the device, and thus boost the amount of light emitted. He invented a process for creating LEDs with many tiny star-shaped pillars on the surface. Each pillar is made up of five nanolayers specifically engineered to help “carry” the light out of the LED material and into the surrounding air.

new brighter smart more efficient LEDMa’s patent-pending technology, called GRIN (graded-refractive-index) LEDs, has demonstrated a light-extraction efficiency of 70 percent, meaning 70 percent of light escaped and only 30 percent was left trapped inside the device—a huge improvement over the 25 percent light-extraction efficiency of most of today’s unprocessed LEDs. In addition, GRIN LEDs also have controllable emission patterns, and enable a more uniform illumination than today’s LEDs.

Overall, Ma’s innovation could lead to entirely new methods for manufacturing LEDs with increased light output, greater efficiency, and more controllable properties than both surface-roughened LEDs and the LEDs currently available in the marketplace.

               

AIXTRON SE, a provider of deposition equipment to the semiconductor industry, last week announced revenues and minimal EBIT loss for the fiscal year 2012.

A slow recovery of revenues but a virtually flat order intake throughout the year reflects a reluctant investment attitude by customers and a continuation of macroeconomic uncertainty, said AIXTRON officials. Despite an improving market consensus on the potential outlook for the back end of 2013, management is unable at this stage to offer a precise revenue and EBIT margin guidance for the year, due to the prevailing low visibility.

Management expects demand for MOCVD production equipment to potentially improve as demand for LEDs increases later in the current year. On the same timeline, management also foresees incremental equipment demand coming from non-LED emerging MOCVD applications and other technology markets, including silicon and organic semiconductor applications. Nevertheless, the exact timing of that order intake pickup is difficult to predict whilst order visibility remains so low.

“2012 proved to be an exceptionally challenging year for AIXTRON, largely due to the severe and extended macroeconomic headwinds that the whole world has been suffering from,” said Paul Hyland, President and Chief Executive Officer of AIXTRON. “Our original expectation that 2012 would develop into a transitory year with the prospect of a significantly better second half has evidently not materialized.

However, the ongoing, albeit low level of demand seen in the second half of 2012 and into 2013, has AIXTRON’s management believing they have reached the bottom of the current cycle. Officials from AIXTRON say it is reasonable to expect to see further market recovery at some point during 2013, driven by increasing demand for LED manufacturing equipment.

AIXTRON also believes they will see an increased demand for the equipment for non-LED applications. AIXTRON management plans to focus now on cost control and cash flow, while continuing R&D investments into future market opportunities.

Recently, as the importance of environmental protection grows, the method of saving energy of products and using eco-friendly materials is on the rise. Of these, since lighting accounts for about 20% of the overall power consumption, the efforts to replace with high-efficiency and eco-friendly products are being made actively. Accordingly, in terms of replacing conventional lightings such as low-efficiency incandescent lamps or fluorescent lamps using an environmentally hazardous substance like mercury with high-efficiency and eco-friendly products such as OLED or LED, the effect is expected to be very large.

In particular, OLED lighting is a surface style and can be manufactured in a transparent or flexible appearance, and has characteristics that realize excellent color rendering and a variety of colors. OLED lighting is drawing attention as a next-generation lighting to bring a new paradigm to the lighting industry since it can change even people’s way of living innovatively in the future through a variety of designs.

Global lighting manufacturers such as Osram or Philips have been prepared for the commercialization of OLED lighting, and began the sales of OLED lighting panels five years ago. After Osram released the world’s first OLED panel in 2008, the sales of the products with improved performance and reduced costs are increasing in recent years.

Based on such trend, IHS Displaybank is to assist in examining the status and the potential for development of the OLED lighting market by publishing a report of Lighting OLED Module Industry Analysis and Market Forecast 2012, which analyzes the general lighting OLED module industry and the market. In addition, the report also helps viewers predict the position of OLED industry in the lighting industry by including the overall light source market forecast for general lighting.

IHS Display forecasted that OLED will penetrate the lighting market gradually by its several optical excellence and the advantage of being transparent and flexible shape, despite the high selling price and limited application market formed in the initial period of the mass production. In particular, the competitiveness of OLED products is analyzed to be strengthened further in the lighting industry from year 2016-2018 when the improvement of efficiency, and the reduction of the cost ratio are significantly achieved.

Recently, considering the speed of the recent OLED lighting development, the efficiency of a 100x100mm2-sized OLED module is expected to exceed 200lm/W, and the net material costs are predicted to be reduced to less than $3.

ams AG (SIX: AMS), a designer and manufacturer of high-performance analog ICs for consumer and communications, industrial and medical and automotive applications, today introduced a new intelligent LED driver for mobile phone cameras that maximizes the brightness of the flash without causing the phone’s battery to fall below its minimum operating voltage.

The AS3649 LED driver uses an innovative “diagnostic pulse” – a burst of controlled high current lasting a few milliseconds – immediately before every flash operation. During this pulse the device measures the momentary voltage across the terminals of the phone’s battery. On the basis of this measurement, it reports a value for the highest flash drive current the battery can sustain, up to a maximum of 2.5A, without dropping below its minimum voltage and triggering the phone to reset itself during the main flash.

Drawing on analog sensing technology developed by ams, the AS3649 measures the battery voltage and current with high accuracy, enabling it to precisely calibrate the optimal LED drive current under any given conditions.

Mobile phones that use the AS3649 can therefore generate the brightest possible flash light, without the need for a bulky auxiliary power source such as a super-capacitor. Users can then benefit from higher image quality and higher resolution. When taking pictures of fast-moving objects, a brighter flash enables the use of faster shutter speeds for sharper, clearer pictures.

The introduction of the LED driver AS3649 also allows mobile phone manufacturers to markedly reduce the engineering and software development effort involved in flash LED implementation. Today, manufacturers exhaustively test the operation of each mobile phone model’s LED flash system under all possible operating conditions, and at all operating voltages. The results of these tests are encoded in a software look-up table stored on the phone. Whenever the camera calls for the flash to be operated, the phone’s processor must read from the look-up table an estimate for a safe drive current value.

The diagnostic pulse technique implemented by the AS3649 eliminates virtually all of this engineering effort, since it is able to measure the actual behavior of the battery at the time of use, instead of estimating it beforehand on the basis of sampled test results.

The AS3649 supplies up to 2.5A to a single LED or up to 1.25A each to two LEDs.  The device’s current-source architecture provides for thermal management, and an on-board NTC (temperature sensor) automatically reduces the current to the LED if it exceeds a programmable temperature threshold.

“Consumers look carefully at camera performance when choosing a mobile phone – it is a key differentiator,” said Ronald Tingl, senior marketing manager at ams. “By using the AS3649, handset manufacturers can achieve the best possible lighting for pictures taken in dark conditions, and at the same time benefit from eliminating the huge effort involved in qualifying all components stressed by high LED flash drive currents.”