March 2018 - Power Systems Design

March 2018

Special Report: Lighting & Illumination (pg 22)

VIEWpoint

LEDs light the wayBy Ally Winning, European Editor, PSD

POWERline

LYTSwitch-6 LED Drivers From Power Integrations

MARKETwatch

Innovations in Lighting and Illumination

DESIGNtips

Dual 9A, Step-Down μModule Regulator with Digital Power System ManagementBy Jian Li, Applications Engineering Section Leader, Yingyi Yan, Applications Engineer, and Marvin Macairan, Associate Applications Engineer, Power Management Products,

Linear Technology Corp.

COVER STORY

The Silicon Carbide revolution -

reliable, efficient, and cost effective

By Giovanbattista Mattiussi Product Marketing Manager, and Damijan Zupancic Application Engineer, Infineon Technologies

TECHNICAL FEATURES

Supervisory Circuits

Get More from Your System with a Cutting-Edge Supervisory ICBy Dragan S. Maric, PhD, Senior Field Applications Engineer, Nazzareno (Reno) Rossetti, PhD EE, Ole Dreessen, Senior FAE, Maxim Integrated Products

Legislation

Energy Labeling for External Power Supplies are Getting Tougher By Jeff Schnabel, VP of Global Marketing, CUI

Power Supplies

Power supplies for railway applications - On the rails to 2020

By Patrick Le Fèvre, Powerbox

SPECIAL REPORT:LIGHTING AND ILLUMINATION

Single 2MHz Buck-Boost Controller

Drives Entire LED Headlight

By Keith Szolusha. LED Drivers Applications Manager, Analog Devices

The Switches Behind Today’s LED

Lighting Applications

By Mike Bolduc, Global Marketing Man-ager, Industrial & Medical Segments, C&K

The future of microLED displays

using next-generation technologies

Myles Blake, Marketing Director, Plessey Semiconductors

Smart yet frugal - energy saving

next generation lighting

By James Lee, Lighting Segment,

ON Semiconductor

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Horticulture lighting drives

plant growth

Svenja Mahler, Product Sales Manager Opto (LED IR), Rutronik

FINALthought

Manufacturing logistics are key to productivityBy Ally Winning, European Editor, PSD

Dilbert

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Highlighted Products News, Industry News and

more web-only content, to:

www.powersystemsdesign.com

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COVER STORY

The Silicon Carbide revolution – reliable, efficient, and cost effective (pg 8)

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#LEDITGROW

High efficacy

Individually adjustable color spectrum

for each plant

Full color spectrum available incl.

white, UV and IR-LEDs

Low thermal resistance

Electrically neutral thermal path

One footprint for all colors

Horticulture LED Lighting

New horticultural products from the high power ceramic series. Specially chosen wavelengths

(450 nm, 660 nm and 730 nm) increase photosynthesis, optimizing plant development and

growth. With outstanding PPF-value, small size and low power consumption, the WL-SMDC

is the future choice for horticultural lighting. Available ex stock. Samples free of charge.

For further information please visit:

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For a short introduction of Horticulture

LEDs read our Application Note:

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HortiCoolture.LED it grow!

for each plant

Full color spectrum available incl.

white, UV and IR-LEDs

Low thermal resistance

Electrically neutral thermal path

One footprint for all colors One footprint for all colors

See you at APEC & PCIM Europe

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POWER SYSTEMS DESIGN

Welcome to the March edition of PSD. This month it is all about LEDs. LEDs have come a long way since they were primarily used as little green or red indicators on consumer equipment. From that lowly beginning, they seem to have taken over all forms of lighting and are now making their way into more diverse applications. In what seems like under a decade, LEDs have replaced lighting in homes, in work and even in sports stadiums.

Six years ago, the San Francisco 49rs decided that LED lighting was too much of a risk for the team’s Levi Stadium. Now LED lighting is routinely used in new stadiums as it offers a better quality of light, a longer serviceable lifetime, energy cost savings and it requires a lot less maintenance. It is estimated that lighting took up 20% of the energy generated globally before the LED revolution, so any effort to reduce that figure is more than welcome.

Of course, there are some drawbacks too. LEDs are not as easy to power as conventional lighting, and they can’t be dimmed by reducing the voltage without a corresponding reduction in the lifetime of the luminaire. But, as with any other issue, technology has solved almost all of these challenges. For example, pulsing the voltage instead of cutting it gives the same dimming affect without the negatives. Although LEDs are now well established, care still needs to be taken on the power side of the installation. This month, On Semiconductor takes a look at LED power requirements and how they can be met.

From lighting as a prime focus, LEDs then moved into backlighting for televisions, producing better brightness and more vivid colouring in thinner, cheaper televisions. Of course, you can’t keep a good technology down, and LEDs weren’t destined for such a secondary, supporting role. Initially OLED technology was used for the primary display and now, newer displays are on the way that use traditional LEDs as the primary display technology. These displays feature microLEDs as pixels and combine red, green and blue sub-pixels to reproduce any colour. For the moment, their use is limited to AR, VR and HAD displays, but for how long will that be the case? If their recent history has told us anything, it won’t be too long. In this issue Plessey Semiconductor looks at the potential of the technology, which has been predicted to be integrated in 330 million units by 2025.

If lighting and displays weren’t enough, LEDs are also making our food production more efficient. The lighting from LEDs can be tuned to precise wavelengths and intensities, and by syncing the lighting from LEDs to a plant’s growth cycle, we can produce bigger and more nutritious food. To provide more depth to the use of LEDs in the horticultural sector, Rutronik will go into detail on the products and techniques that are used and the results that can be achieved.


Best Regards,

Ally Winning European Editor, [email protected]

LEDs light the wayPower Systems Corporation 146 Charles Street Annapolis, MD 21401 USA Tel: +410.295.0177Fax: +510.217.3608 www.powersystemsdesign.com Editorial Director Jim Graham [email protected]

Editor - EuropeAlly [email protected]

Editor - North AmericaJason [email protected]

Editor - ChinaLiu [email protected]

Contributing Editors Kevin Parmenter, [email protected]

Publishing DirectorJulia [email protected]

Creative Director Chris [email protected]

Circulation Management Sarah [email protected]

Sales Team Marcus Plantenberg, [email protected]

Ruben Gomez, North America [email protected]

Registration of copyright: January 2004ISSN number: 1613-6365

Power Systems Corporation and Power Systems Design Magazine assume and hereby disclaim any liability to any person for any loss or damage by errors or ommissions in the material contained herein regardless of whether such errors result from negligence, accident or any other cause whatsoever.

Free Magazine Subscriptions, go to: www.powersystemsdesign.com

Volume 15, Issue 2

The UltimatePower Couple

With their high K and small size, these 1:1 coupled inductors are the perfect match for your SEPIC and flyback applications

High Current MSD Series

Offered in thirteen body sizes and hundreds of inductance/current rating combinations, our MSD/LPD families are perfectly coupled to all your SEPIC and flyback designs.

The MSD Family offers current rat-ings up to 16.36 Amps, low DCR, coupling coefficients as high as K ≥ 0.98, and up to 500 Vrms winding-to-winding isolation.

With profiles as low as 0.9 mm and foot-prints as small as 3.0 mm square, the LPD Family offers current ratings up to 5.6 Amps, DCR as low as 0.042 Ohms and coupling coefficients as high as K ≥ 0.99.

You can see all of our coupled inductors, including models with turns ratios up to 1:100, at www.coilcraft.com/coupled.

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POWERline


Power Integrations, a leader in high-efficiency, high-reliability LED-driver ICs, has announced the

LYTSwitch™-6 family of safety-isolated LED-driver ICs for smart lighting applications. The new ICs deliver flicker-free output up to 65 W, and feature up to 94% efficiency and as little as 15 mW standby power, with configuration options for two-stage or single-stage PFC support. Targeting smart residential and commercial fixtures and low-profile ceiling troffers, LYTSwitch-6 ICs also exhibit fast transient response, which facilitates excellent cross regulation performance of parallel LED strings without additional regulator hardware, and allows easy-implementation of a pulse-width-modulation (PWM) dimming interface. LYTSwitch-6 ICs include both constant-voltage (CV) and constant-current (CC) operation, enabling lighting manufacturers to reduce the number of product variants, resulting in manufacturing and logistics savings. The new ICs are protected by an advanced thermal foldback system which prevents overheating while delivering as much light as thermally possible in any circumstance or installation.

LYTSwitch-6 ICs feature a builtin 650 V or 725 V MOSFET and

LYTSwitch-6 LED Drivers From Power Integrations

secondary-side FluxLink™ control which eliminates the need for an optocoupler and provides highly accurate output with better than 3% CV and CC over line, load and temperature. Power conversion for the flyback stage is more than 94% efficient, achieved by using synchronous rectification and quasi-resonant switching which enables high power output without a 1 heatsink. For example, a 35 W, 12 V, 2.92 A design with an additional PFC circuit has been demonstrated to be over 89% efficient. Devices offer low standby power — less than 15 mW in universal AC input conditions – even with line voltage sensing, which allows the IC to protect itself from mains voltage surges and swells. Comments Hubie

Notohamiprodjo, Director of Product Marketing for LED Lighting at Power Integrations “LYTSwitch-6 ICs are ideally suited to smart lighting applications with multiple outputs. By eliminating heatsinks and optocouplers and reducing the size of the output capacitor by as much as 30%, component count and system size are also reduced.”

A reference design (DER-637) describing a 35 W PWM-dimmable LED power supply with efficiency over 89% and a power factor greater than 0.9 is available for download from the Power Integrations website at:

Power Integrationshttps://www.power.com/lytswitch-6/

By: Kevin Parmenter, PSD Contributor

Innovation in electronics in lighting is rapidly boosting the efficiency of converting electrical energy into light.

Not only has electronics provided increased efficiency, the ability to turn lighting on and off or modulate the intensity based on need has greatly improved.

LED lighting is rapidly replacing incandescent, halogen, fluorescent and various high intensity discharge lighting systems. The growth of LED lighting has been dramatic with a significant potential for replacing all other methods . From power electronics perspective, LED lighting offers the best opportunities for replacement of traditional lighting methods. Except for incandescent and halogen lamps, other technologies require electronics such as ballasts ‒great for those of us in power electronics. CFL’s HID lamps, including low pressure and high-pressure sodium mercury vapor and metal halide, all need some form of ballast with various degrees of electronics to operate properly. Halogen and incandescent still have a place in some niches such

Innovations in Lighting and Illumination

as oven lighting where other technologies cannot tolerate the environment or where heat is a desired byproduct=such as keeping pipes from freezing in winter weather.

The market for grow lighting is skyrocketing for both legal and non-legal purposes. Of the various technologies other than incandescent and halogen, LEDs can be easily dimmed as needed and not just either on or off control.

As LEDs improve from a lumens per watt and dollar per lumen perspective, they keep displacing traditional lighting methods in a wide range of applications including commercial, industrial, aviation and transportation. LED lighting in electric vehicles helps conserve batter life and provides a better lighting experience as well. One of the agricultural applications includes grow lights for legal as well as semi-legal and illegal plants and this seems to show no signs of slow down. There are some additional benefits to LED lighting in horticulture that the wavelengths can be tuned to match the spectral distributions

of the plant’s needs.

One of the top opportunities for LED lighting is the replacement of street lighting to offer a better color temperature for more natural lighting as well as higher efficiency. The market for electronic lighting is highly competitive like the consumer electronics industry. The cost pressures are intense from both the LEDs the components and the ballasts and lighting power supplies themselves. The cost pressures and pace of change are intense across the entire supply chain. Global competition in these areas is also extreme. The environments for lighting, especially street lighting, have high transients and surges on the supply lines, and since the sensitive electronics are replacing electrical ballasts, they are expected to survive all this with little revenue available to provide it. At the same time, warranties are lengthy, with seven to ten years becoming the norm for lighting electronics. The market is huge if you can survive the margin pressures.

PSDwww.powersystemsdesign.com

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DESIGN t ips

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Dual 9A, Step-Down μModule Regulator with Digital Power System ManagementBy: Jian Li, Applications Engineering Section Leader, Yingyi Yan, Applications Engineer, and Marvin Macairan, Associate Applications Engineer, Power Management Products, Linear Technology Corp.

The LTM4675 is a dual 9A or single 18A step-down μModule®

(micromodule) DC/DC regulator featuring remote configurability and telem-etry monitoring of power system management (PSM) parameters over PMBus—an open standard I2C-based digital interface protocol. Its 16mm x 11.9mm x 3.51mm BGA package includes analog control loops, preci-sion mixed-signal circuitry, EEPROM, power MOSFETs, induc-tors and supporting components. It features a wide 4.5V to 17V input voltage range, and a 0.5V to 5.5V output voltage range with ±0.5% DC accuracy over temperature. LTM4675’s power outputs can be digitally adjusted, margined and powered up/down at program-mable slew rates and sequenc-ing delay times. Maximum turn-on time is 70ms. Telemetry read back parameters include VIN, IIN, VOUT, IOUT temperature, run-ning peak values, uptime, faults and warnings. Current read back

accuracy is ±2.5% at 9A load over temperature.

The LTM4675 facilitates the design of high efficiency, high power den-sity and high reliability solutions for telecom, datacom and storage systems, plus industrial and instrumenta-tion power supplies. The LTM4675 is offered in a 16mm x 11.9mm x

3.51mm BGA package available with SnPb or RoHS compliant terminal finish.

Dual 9A μModule Regulator with Digital Power System Management

Figure 1 shows a typical LTM4675 application, and Figure 2 gives an indication of the device’s com-pact footprint. The input voltage range is 5.75V to 17V, and the outputs are 1V/9A and 1.8V/9A. Figure 3 shows the efficiency for each output of the LTM4675 for a variety of output voltages vs load current. The LTM4675 can achieve high efficiency over a wide oper-ating range, with high reliability. Figure 4 shows that the maximum case temperature is 84.1°C when the module is running with a 12V input, 1V/9A and 1.8V/9A outputs, without airflow.

The LTM4675 offers internal compensation or external com-pensation, which can be used to optimize the transient response to load current steps over a wide operating range.

The LTM4675 supports a PMBus-compliant SMBus serial interface up to 400kHz. Readable data in-cludes input and output voltages, currents, temperatures, running peak values, uptime, faults, warn-ings and an onboard EEPROM fault log record. Writable data and

Figure 1: 9A, 1V and 9A, 1.8V Output DC/DC μModule Regulator with Serial Interface

Figure 2: The LTM4675 features a highly compact footprint

configurable pa-rameters include output voltage, voltage sequenc-ing and margining, digital soft-start/ stop ramp, OV/UV/OT, UVLO, fre-quency and phas-ing. The LTM4675 guarantees high accuracy telemetry read back with an integrated 16-bit ΔΣ ADC.

Multi-Module Operation for High Current Applica-tionsThe LTM4675 utilizes a constant frequency peak cur-rent mode control architecture, which enables cycle-by-cycle current limit and easy current sharing among phases when the channels are operated in parallel. For higher output current capability, it’s easy to parallel multiple LTM4675 mod-ules. Furthermore, the LTM4675 can be used as a master to drive non-PSM power modules to pro-vide much higher output current. For example, the LTM4675 can drive three LTM4630s to provide up to 125A output current. Figure 5 shows the thermal picture of this application. With 400LFM of airflow, the hot spot temperature rise is only 66.2°C. The uniform thermal distribution among the

Figure 3 LTM4675 Single Channel Efficiency at VIN = 12V Figure 4 Thermal Performance of LTM4675 at VIN =

12V, VOUT0 = 1V/9A, VOUT1 = 1.8V/9A, No Airflow, Tested on DC2053A. Maximum Temperature Rise = 61.1°C, TA = 23°C

Figure 5 Thermal Picture at VIN = 12V, VO = 1.0V/125A, 400LFM Airflow, Maximum Temperature Rise = 66.2°C, TA = 23°C

modules is due to excellent current sharing performance.

ConclusionLTM4675 is a high efficiency and high power density μModule regu-lator with built-in digital power system management. With all of the features mentioned above, the LTM4675 is ideal for telecom, datacom and storage systems, industrial and instrumentation applications.

Linear Technologywww.linear.com

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COVER STORY


The SiC revolution – reliable, efficient, & cost effective

By: Giovanbattista Mattiussi Product Marketing Manager, and Damijan Zupancic Application Engineer, Infineon Technologies

Silicon Carbide (SiC) devices have seen a substantial rise in popularity

Over the past few years, Silicon Car-bide (SiC) devices have seen a sub-

stantial rise in popularity. This has been fueled by an increased focus on saving energy, reducing the size of devices, and improving the long term reliability of the final products. Traditional silicon-based devices are reaching the physical and material limits of what is pos-sible. The new SiC-based devices allow us to push those limits aside and reach for the higher voltages, lower conduction and switching losses, and high efficiency and reli-ability that we need to design and produce the revolutionary energy-smart devices of the future.

Infineon SiC solutions such as the CoolSiC™ family of products are an essential part of this rapidly expanding energy-smart SiC revo-lution. Within this family of Infi-neon’s CoolSiC™ devices are the Schottky diodes, which target ap-plications in server and PC power, telecom equipment power, and PV inverters. The latest development in the CoolSiC™ Schottky diode family, the sixth generation or G6, is the end result of many iterative

steps over the past 17 years. Start-ing in 2001, Infineon released the first generation CoolSiC™ Schottky barrier diode. This was followed up in 2004 with the second genera-tion diode which had a merged pn junction and high surge current capability. In 2009, the third gener-ation introduced diffusion solder-ing which results in lower thermal resistance from junction to case (RthJC). 2012 saw the introduction of thin-wafer technology, and in 2017, the sixth generation adds on

a new layout, a new cell structure, and a new proprietary Schottky metal system. The latest features provide substantially increased re-liability, quality and efficiency over all load conditions, and increases the power density as well.

Improving PFC efficiencyApplication engineers, powers supply designers and academics who work with high-efficiency and high-density powers supplies have to focus on many different aspects

of the power supply design. The boost stage, or PFC stage, of the AC-DC converter is one place where the CoolSiC™ Schottky diode 650 V G6 can really show its strengths in supporting highly efficient, compact power supply designs.

One of the interesting features of the CoolSiC™ Schottky diode 650 V G6 is its best-in-class low forward voltage. This allows designers to realize efficiency improvements over a wide range of loads and provides some interesting results in the power factor correction.

Infineon did some real world testing on a PFC test board that illustrates this quite effectively. The board used in the test was an 800 W 65 kHz and 130 kHz Platinum rated server power fac-tor correction evaluation board (EVAL_800W_130PFC_C7). A com-parison in the measured efficiency between a CoolSiC™ Schottky di-ode 650 V G5 (IDH06G65C5) and a CoolSiC™ Schottky diode 650 V G6 (IDH06G65C6) can be seen in Table 1 and Table 2.

What do these results really mean though? This test board shows an average 0.05 percent improvement in efficiency of the G6 diode over the G5 diode. This translates into a 1 percent improvement in power losses.

Taking it to the next stepThere is more than can be done here beyond simply using the next generation SiC-based diode. A

simple adjustment in the current rating of the boost diode pro-duces some additional interesting changes in the measured efficiency of the power supply. Again a real-world test was performed using the same 800 W 65 kHz and 130 kHz Platinum rated server power factor correction evaluation board with a 6 A diode and a 10 A Cool-SiC™ Schottky diode 650 V G6 diode. The combined results are shown in Figure 2.

The result shows something quite interesting. The increased cur-rent rating results in an efficiency improvement, which is linked to lower conduction losses. Replac-ing the 6 A boost diode with a 10 A boost diode shows an efficiency improvement of up to 0.2 percent at maximum output power. It is important to note though that the 6 A diode behaves better under light loads due to lower capacitive charge (Qc) which means lower switching losses.

The balance between light and full load efficiency and the current rating of the boost diode means that the power supply design can be easily optimized according to the price and performance requirements.

Thermal performanceThe high efficiency of the Cool-SiC™ Schottky diode 650 V G6 and reduced power losses result in lower operating temperatures for the diode. Conduction losses are at the heart of the majority of the heat generation under

Figure 1: 800 W 65 kHz and 130 kHz Platinum rated server power factor correction evaluation board

Table 1: Measured efficiency of the 800 W PFC board at 65 kHz

Table 2: Measured efficiency of the 800 W PFC board at 130 kHz

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COVER STORY


full load conditions. The design improvements have introduced a lower forward voltage (Vf) in the new CoolSiC™ Schottky diode 650 V G6 diode which results in temperatures (measured and simulated) that are around 1 °C lower after 100 μs than the previous generation diode (CoolSiC™ Schottky diode 650 V G5).

Protecting the PFC circuit against surge eventsWhen power supplies are used in harsh environments and you are using a SiC Schottky diode in your PFC design, it is very important to consider how the inevitable power surge events will be handled. The new SiC Schottky diodes have reduced conduction losses, but that improvement comes at a cost of lower surge current parameters in some areas. Restricting the

forward current though the SiC diode is simple enough with the implementation of a bipolar bypass diode which will conduct only when the rectified voltage is higher than the output voltage. Figure 3 shows a simplified example of how this can be done.

ConclusionThe CoolSiC™ Schottky diode 650 V G6 is a leading edge solution from Infineon. It takes full advantage of the clearly demon-

Figure 3: Simplified classic PFC circuit diagram with a bypass diode

strated benefits of SiC over silicon. Built around a proprietary innovative soldering process pio-neered by Infineon, it in-cludes features such as a compact design, thin-wafer technology, and a new Schottky metal sys-tem. The lower forward voltage of the CoolSiC™ Schottky diode 650 V G6 means that you see lower conduction losses, which in turn mean you see higher efficiency and lower junction tem-peratures. The result is a family of SiC products with a best-in-class figure of merit (Qc x VF),

and improved efficiency over all load conditions.

Combining the advanced techno-logical features and benefits of SiC with Infineon’s proven quality and reliability, you can be sure that your power supply designs will maximize the system performance and take full advantage of all of the incredible potential of SiC devices.

Infineon Technologieswww.infineon.com

Figure 2: Measured efficiency of the 800 W PFC board - different current rating

Get More from Your System with a Cutting-Edge Supervisory IC

By: Dragan S. Maric, PhD, Senior Field Applications Engineer, Nazzareno (Reno) Rossetti, PhD EE, Ole Dreessen, Senior FAE – Maxim Integrated Products

They monitor critical electronic loads

Supervisory integrated circuits are ubiquitous in electronic systems. They monitor critical

electronic loads, enabling them only after the supply rails have settled within specified values. This simple task often becomes challenging as the supervisory IC may be required to operate in a noisy environment or in an application starved for space or powered by a limited energy supply. This article reviews some typical applications and the challenges they pose to the supervisory IC and introduces a new family of highly integrated devices that overcome them.

Better Noise Immunity in the Automotive EnvironmentThe automotive environment is subject to electromagnetic interference due to both external and internal sources. The “arc and spark” noise that comes from ignition components (Figure 1), motors, and similar pulse-type systems affects the electronics supply rails by producing disruptive undervoltages or overvoltages. Noise tolerance or immunity is an important factor when

selecting the car’s electronic components.

In Figure 2, a microprocessor supervisory IC controls the car’s remote camera modules, controller area network (CAN), serializer, and deserializer. Each electronic load correctly operates within its specified input voltage range. The operating range of each load is limited by the accuracies of the power supply and the supervisory IC, along with the input-voltage noise amplitude. An accurate supervisory IC will provide more margin against noise. For example, a ±0.5% accuracy advantage on a 3V

supervisory threshold will provide an extra noise immunity of 15mV.A wide VDD input voltage for the supervisory IC range like the one indicated in Figure 2 offers

Figure 1: Spark Plug Firing

Figure 2: A Supervisory IC Controls a Remote Camera Module, CAN, Serializer and Deserializer

SUPERVISORY CIRCUITS


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SUPERVISORY CIRCUITS


voltage at the input falls within the factory-set window threshold. These integrated supervisory and OTP circuits significantly improve system reliability and reduce solu-tion size compared to separate ICs or discrete components. The MAX16132–MAX16135 are fixed-threshold devices. The nominal input voltage for any input is factory programmable from 0.5V to 5.0V, providing a wide range of threshold selections. The reset outputs are active-low, open-drain, and are guaranteed to be in the correct reset output logic state when VDD remains greater than 1.0V. All devices are offered with 23 reset timeout periods ranging from 20μs (min) to 1200ms (min).

All reset outputs share the same factory-set reset timeout period. The MAX16132–MAX16135 are specified over the automotive tem-perature range of -40°C to +125°C.

ConclusionWe reviewed the challenges of a supervisory IC that is pow-ered by a limited energy supply, operates in a noisy environment or in an application starved for space. The MAX16132–MAX16135 are low-voltage, low-supply-current, ±1% accurate, OTP-protected, single/dual/triple/quad-voltage μP supervisors in a small SOT23-8 package. They overcome all of these challenges by enabling solutions that con-sume less power, have better noise immunity, and occupy less PCB space.

Maxim Integrated Productswww.maximintegrated.com

Figure 5: The SOT23-8’s Size Advantage

Figure 6: MAX16132 μP Supervisor Block Diagram

flexibility and more margins against noise.

Accuracy Saves Power in PortablesIn portable applications, an accurate supervisory IC can be leveraged to set the electronic load voltage lower, therefore saving power. A supervisory IC with an accuracy advantage of ±ε% will enable an extra range of operation of ε%. Consider an electronic load that operates at a minimum voltage, VIN. The same electronic load monitored by a supervisory IC with a ±0.5% accuracy disadvantage will have to operate at a higher minimum voltage

1.005VIN. Its associated power loss (proportional to the square of VIN) will be 1% worse in the latter case. This is the same as lowering the electronic load’s power-supply efficiency by 1% point, not

something to be taken lightly.

Low Supply Current Saves Power in PortablesDue to the supply current required for its operation, a supervisory IC may become a significant current drain to a system in sleep mode. However, a supervisory IC designed in a modern CMOS process should reduce the current drawn down to the order of 10μA, minimizing the burden on the battery.

Small Size for Rotary and Linear EncodersIn another example, motion

Figure 3: Rotary Encoder

Figure 4: Encoder ASSP Power Rails Control

encoders—electromechanical devices that convert the linear or angular position or motion of a shaft or axle to an analog or digital signal—squeeze a lot of electronics into a small space. Figure 3 shows an example of a rotary encoder.

Figure 4 shows the application-specific standard product (ASSP), power supply, supervisory/POR/OTP and RS485 interface subsystem embedded in the encoder.

In this application, space is at a premium, and the integration of supervisory and protection functions in a small IC package make a difference. As shown in Figure 5, the MAX16132–MAX16135 μP supervisors are housed in a small SOT23-8 package, in comparison to a similar device housed in a bulky MSOP10. The larger package takes up about twice as much PCB space.

Low-Voltage, Precision μP Supervisors The MAX16132–MAX16135 μP su-pervisors are excellent examples of monitoring ICs that address these challenges. They are low-voltage, low-supply-current, ±1% accurate, OTP-protected, single/dual/triple/quad-voltage μP supervisors that monitor up to four system-supply voltages for undervoltage and over-voltage faults. Figure 6 shows the single-channel device (MAX16132).

The reset is maintained for a minimum timeout period after the

1514

LEGISLATION



Energy Labeling for External Power Supplies are Getting Tougher

By: Jeff Schnabel, VP of Global Marketing, CUI

Energ standards for high-tech products can become more effective

Recent delays in the introduction of mandatory energy-performance standards

should not be interpreted as a slackening in the pace of regulatory change.

Energy-performance standards for high-tech products can become more effective in helping protect the planet by being more broadly adopted worldwide and by setting higher targets through successive revisions. Governments seeking practical ways to meet pledges on combating climate change are continually tightening and extending the rules applicable to buildings and lighting, automobiles, IT equipment, domestic appliances and more, to save energy costs and cut greenhouse gas (GHG) emissions.

The evolution of international regulations on external power supplies (EPS) for home and office electrical equipment provides a perfect illustration. In the early ’90s, the US Environmental Protection Agency (EPA) published the first voluntary codes in response to academic research highlighting the energy wasted by

these devices. Since then, the US Department of Energy (DOE) and other authorities throughout the rest of the world have published specifications aimed at raising the average energy efficiency in active modes and minimizing the power dissipated in standby – sometimes called “vampire power”. The California Energy Commission became the first official body to impose mandatory energy-performance standards, in 2004.

Taking Turns to Raise the BarThe targets for minimum efficiency and maximum standby power differ slightly from territory to territory. However, the majority of developed nations now have energy-labeling criteria in place, and are all moving in the same direction by raising the performance requirements as each revision is published. This can be done in several ways, most obviously by increasing the minimum acceptable average efficiency – usually calculated from the mean of efficiency measurements taken at 25%, 50%, 75%, and full load – or by reducing the maximum allowable standby power. Other ways to tighten the regulations include stipulating additional efficiency

measurements at specified points in the load range. This can ensure a more accurate representation of real-world performance, and discourage EPS manufacturers from optimizing their products purely to pass laboratory tests. Legislators can also extend the scope of regulations to cover power supplies for a wider range of uses.

The development of the European Commission’s Code of Conduct (CoC) for EPS manufacturers provides a case in point. The Commission’s Joint Research Center (JRC), responsible for preparing the CoC, calculates its measures can save as much as 5 TWh of standby power, and a similar quantity of active power, every year. By studying the history of energy labeling protocols as applied to external power sup-plies (figure 1), we can see that the European regulations tend to leapfrog those set by the US DOE. When the DOE published its Level VI framework, the EU introduced CoC Tier 1 as a voluntary code that specified comparable but slightly more demanding targets. Similarly, when the DOE Level VI specifications became manda-

tory from February 2016, the EU upped the ante again by raising the bar further with CoC Tier 2 that introduced an additional minimum efficiency target at 10% of full load. State-sponsored one-upmanship? Perhaps, but the real benefit is that appliances in use today are burning up consider-ably less energy than their predecessors, even though engineers usually also manage to cram in more features to improve the user experience.

The EU could already be planning new limits that are even tougher than those in CoC Tier 2. According to the Review Study on Commission Regulation (EC) NO. 278/2009 External Power Supplies (link below) prepared by Danish consul-tants Viegand Maagø for the European Commis-sion, the combined effects of stricter and wider measures could save up to another 3TWh per year by 2025.

Let’s consider the philosophy that drives the CoC framework. Because the codes are intro-duced on a voluntary basis for manufacturers, it is reasonable to set higher performance targets than would be feasible in a mandatory frame-work. This can incentivize leading companies to drive technological progress at a fast pace, to gain advantages by differentiating their products from those of competitors and to strengthen their reputation in the marketplace. End users, and the environment, benefit through faster re-ductions in utility bills and GHG emissions. As a committed developer of power-conversion prod-ucts, including external power supplies, CUI has successfully introduced products covering a wide range of power ratings and sizes, which comply with both CoC Tier 1 and Tier 2 specifications.

A Chance to Get Ahead?The EU has made clear its intention to mandate these voluntary codes, once they are established and the technologies needed to meet them have been proven. However, although both of these protocols should have become mandatory by now - Tier 1 in 2017, and Tier 2 in January 2018 -

TDK TechnologyAdvancing power solutions.

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LEGISLATION


neither milestone has been met. Today, each remains as a voluntary code, yet to become enforceable legislation. What does this mean for the industry, and for the world? As far as we at CUI are concerned, there is no change in terms of what we do, or our commitment to continuously improving the energy efficiency of our products. Striving to comply with the latest CoC specifications, while they are voluntary codes, means we are already prepared for the transition into law, whenever that may happen.

The exact reason for the delay in legislation may not be known, but we can be sure that the CoC Tier 1 and eventually Tier 2 limits will become law at some time in the near future. EPS manufacturers cannot afford to relax, or assume that authorities are slackening the pace of regulatory advancement. We need to take up the technical challenges set by each new protocol as soon as it is published.

By always using power supplies that meet the latest and most

stringent standards worldwide, OEMs that need to include an EPS in the box with each new product shipped can ensure compliance with the regulations in force in any geographic market, and avoid the complexity of having to manage multiple different product configurations.

The EU’s Tier 2 regulations may have slipped behind schedule from a legal point of view, but the technical pace shows no sign of slowing down.

CUIwww.cui.com

Figure 1: Authorities worldwide have adopted EPS energy-labeling protocols, and introduced stricter targets with each subsequent revision.

Power supplies for railway applications – On the rails to 2020

By: Patrick Le Fèvre, Powerbox

For decades, railway has important area for the power supply industry

In a study presented at the international rail exhibition, Innotrans 2016 in Berlin, the European Rail Industry sum-

marized the state of the business as representing a market size estimated to reach 185 billion Euro by 2020. Of course, the power supplies share of that amount is marginal compared to heavy rolling stock or infrastructure. Though without power supplies, nothing else would be possible. As we approach the next Innotrans exhibition, we can take a minute to consider the many challenges that power supply manufacturers are facing in their quest to make railways safer, coupled with provid-ing the highest service levels for passengers.

From conservative to progressiveFor decades, the railway sector has been an important area for the power supply industry, which needs to develop very specific so-lutions to meet the requirements of this complex market. The sector consists of three main categories: new equipment, modernization, and the maintenance of equipment that entered service 10 years ago or more. Each of these categories represents particular demands on

the developer and requires specific skills.

Although the railway sector is very conservative and priority is given to reliability and robustness, a new generation of “digital technology trained” engineers are increasingly integrating digital control and encouraging the implementation of energy-efficient topologies such as the Gallium Nitride transistors. In the railway sector this approach is quite new, requiring more ex-tensive qualification work during product development and brings new constraints for engineers re-sponsible for guaranteeing durable solutions for the next twenty years.

From point-of-load to multi kilo-watts - with complianceThe range of railway applications is very wide and consists of a large number of applications requiring simple point-of-load (POL) voltage regulators to converters or invert-ers of several hundred kilowatts powering the motors of traction engines and other traction vehicles (Figure 1). In term of the over-all railway market, if we exclude services, rolling stock represents the majority of applications, fol-lowed by infrastructure and finally, track side and signalling. Each of these sub-segments has its own requirements that are specific to its environment.

Figure 1: The range of railway applications is very wide

POWER SUPPLIES


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POWER SUPPLIES


this service life must be taken into account, as well as the possibility of the replacement of certain components, such as electrolytic capacitors affected

by ageing. Knowing that railway power supplies can be exposed to severe environmental effects such as temperature variations or shock and vibration

during the life of the product, equipment manufacturers include “component refreshment and re-calibration” in their specifications. It is common to see products delivered more than 15 years ago return to the workshop for review and updating. This practice is very specific to the railway sector and it has a strong influence on the way feeds are designed.

Indeed, a 30-year lifespan obliges developers to select components with a low risk of obsolescence, but also to design the product for possible upgrades during its useful life. This adds a level of complexity and limits the introduction of new technologies. Engineers in charge of the development of tomorrow's

Figure 4: Powerbox’s Track side Battery Backup Unit (BBU) can be customized in less than three months to meet specific demands, including the addition of radio transmission telemetry systems

For example, in converters for vehicle (e.g. locomotive) start-up control, low-battery-voltage starters (LBVS) are connected to high voltage catenaries to deliver a low battery voltage, requiring very high insulation and high-level safety constraints (Figure 2). In addition, all on-board equipment must comply with general standards such as EN50155, which covers electronic equipment used in rolling stock (a standard that incorporates many other standards, such as EN 50121-3-2 for electromagnetic compatibility). The railway field is highly standardized and each development begins with an analysis of the application case and related standards.

In addition to the traditional standards governing operating quality, operational parameters and safety, this year the EN45545 standard (resistance and fire behaviour) has become mandatory for all rolling stock. This standard aims to eliminate

the risk of fire during a technical incident and all toxic fumes resulting from combustion of the product. For power supply manufacturers, this means selecting compliant components and carrying out additional tests to ensure full compliance with the various chapters of EN45545.

Apart from the large number of standards, one of the idiosyncrasies of the railway sector is the fact that many applications have very specific

requirements in terms of housings and connectors, often resulting in products that are dedicated to a particular customer. While the trend is towards the standardization of card modules such as DC/DC converters (Figure 3), for more complex products such as locomotive starter converters or decentralized battery chargers, the on-demand product remains the norm. This requires a development capacity geared towards these products and a high degree of flexibility in production.

In fact, despite a growing market (+6% per year), the volumes of power supplies used in the railway sector remain modest compared to the millions of units consumed in the telecommunications sector, requiring manufacturers, such as Powerbox, to adapt production tools to specific demands.

Designing power for long life timeThe majority of customers in the railway sector require 30 years or more availability for some critical equipment. During development

Figure 2: Low Battery Voltage Starter require very high insulation and high-level safety constraints

Figure 3: Standardized DC/DC modules are reducing time-to-market and simplifying inventory management and maintenance

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POWER SUPPLIES


railway systems want to integrate new technologies, but the limited knowledge of their lifecycle and sustainability raises questions about the level of risk associated with their introduction. This is a topical issue that is being debated within the railway community, which wants to modernize its power supply systems to make them more energy-efficient and include better communications.

Time to market challengesThe technologies used to develop railway power supplies are very similar to those used in other segments, and with years of experience, developers have built up expertise enabling them to reduce development times. However, new standards and the introduction of new technologies increase development time. Considering the wide range of power supplies used in railways, if we exclude “standard” products, more complex projects can easily reach 24 or even more months without approval. This means working closely with OEMs who, aware of these delays and facing increasing competition from Asia, are pushing for the development of functional blocks that can be reused on multiple projects.

Because of the large and increas-ing demand for modernization of rail systems, design lead times have to be short, which requires a different approach. In the case of rolling stock, this involves specific constraints, such as certifications. In the case of traffic control and

signalling systems, the constraints are less stringent and it is possible to use power supplies, such as those for DIN rail mounting that already exist. An energy subsystem such as Powerbox’s Battery Backup Unit (BBU) can be customized in less than three months to meet specific demands, including the addition of radio transmission te-lemetry systems (Figure 4). This is the type of modularity that OEMs are beginning to implement in roll-ing stock, but it will take time.

The impact of modernizing railway networks has many aspects be-cause it is not conceivable to stop the operation of lines, nor to re-place all existing infrastructure. For rolling stock, this often involves the addition of complementary technologies such as Wi-Fi for pas-senger comfort or on-board telem-etry to increase safety. In this case, the power supplies are of a rather standard type and are often part of the installed system without any major changes to rolling stock.

In the case of the major refur-bishment of a complete train, equipment manufacturers ask power supply manufacturers to develop Fit, Form and Function (3F) alternatives. That is, revised, updated power supplies but where the units’ fit, form and function remain the same, thus reducing implementation delays and guar-anteeing the durability of the host equipment for many years. The development of a 3F power supply is very close to a specific develop-ment, but by combining the exper-

tise of engineers, the platforms available from manufacturers specialized in the field of railroads, and the reuse of the original case or chassis, it is possible to reduce development time spectacularly.

Most of the modernization of European rail networks is carried out at the track and signalling system level. Accordingly, install-ers ask for 3F solutions from the power supply manufacturers that can be installed in place of the old systems; a relatively simple process of “old equipment out, new equipment in”. For very old systems, the technique used is to install an industrial chassis in the cabinet to facilitate the installa-tion of standardized racks, which subsequently reduces the time required for updating, such as adding additional radio-telemetry systems or connecting the cabinet to fibre optic systems.

The general trend in railway power supplies is to reduce develop-ment times by adopting standard-ized or semi-standardized sub-assemblies. This is the will of the equipment manufacturers and increasingly the adopted solution for systems close to the tracks, or embedded applications using card converters or cassettes. However there will always remain very specific power supplies requiring on-demand solutions that will continue to call upon very specific skills.

Powerboxwww.prbx.com

Special Report:Lighting & Illumination

Inside:

Single 2MHz Buck-Boost Controller Drives Entire LED Headlight...

The Switches Behind Today’s LED Lighting Applications...

The future of microLED displays using next-generation technologies...

Smart yet frugal - energy saving next generation lighting...

Horticulture lighting drives plant grown...

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SPECIAL REPORT : LIGHTING & ILLUMINATION



Single 2MHz Buck-Boost Controller Drives Entire LED Headlight

By: Keith Szolusha. LED Drivers Applications Manager Analog Devices Inc.

Cluster can have vastly different driver requirements

Automobile LED headlight clusters combine high and low beams, daytime

running lights, and sometimes signal and clearance lights into a single headlight cluster. The components of the cluster can have vastly different driver re-quirements, including voltage and current requirements, topologies, power levels or unique dimming functions. Meeting the range of requirements usually means em-ploying separate driver solutions. Using multiple drivers not only complicates BOMs and pro-duction; it can make it difficult to meet EMI standards. Each additional driver adds its high frequency signals to the EMI mix, complicating EMI quali-fication, troubleshooting and mitigation.

Although the headlight clus-ter for each automobile make and model may be outfitted with a creative variety of LED currents and voltages, they commonly top out at 30W total. With that in mind, there should be a number of driv-ers that satisfy the power and feature re-quirements of every

string in the cluster. There are not. Such a driver needs to take the rel-atively wide battery voltage range, and using a buck-boost topology, convert to the wide variety of string voltages. It needs to be small and versatile, to fit easily into the space constraints of the cluster, and pro-duce little EMI, to minimize R&D efforts and eliminate the need for costly metal-shielded EMI cases. It should also be efficient. The Power by Linear LT8391A 2MHz buck-boost controller is unique in satisfying all of these require-ments, making it possible to drive

the entire headlight cluster, and more, with a single controller.

LT8391a 2MHz synchronous controller with low EMIThe LT8391A is the first-of-its-kind 2MHz buck-boost controller for LED current regulation. The very high 2MHz switching speed enables the use of a single, small inductor and small overall solution size for high power LED applica-tions. Unlike monolithic convert-ers, whose power switches are contained within the IC package, controllers such as the LT8391A

can drive external power switches with much high-er peak currents, such as 10A. Such peak currents would burn up the small IC packages of typical integrated converters. In contrast, a controller with external 3mm × 3mm synchronous MOSFETs can deliver much higher power. These MOSFETs can be arranged in tight quarters with hot-loop ca-pacitors for very low EMI. The unique peak switch current sense ampli-

fier architecture places the sense resistor next to the power induc-tor, which is outside of the criti-cal input and output hot loops—reducing EMI. Optional spread spectrum frequency modulation (SSFM) further reduces the con-troller’s EMI.

The 2MHz LT8391A 16V, 1.5A (24W) buck-boost LED driver in Figure 1 boasts as high as 93% efficiency with EMI filters and gate resistors as shown in Figure 2. Efficiency is 1%–2% higher with the optional EMI components removed. With small 3mm × 3mm

MOSFETs and a single high power inductor, the tem-perature rise for this converter is low, even at 24W. At 12V input, no com-ponent rises more than 25ºC above room temperature. At 6V input, the hottest component rises less than 50ºC with a standard 4-layer PCB and no heat sink or airflow. It continues to run at full 24W load in the face of input transients down to 4.3V; or reduced load current via analog or PWM dimming when the input drops for long periods. The 8A–10A sense resistor makes this

Figure 1: LT8391A 2MHz 16V, 1.5A automotive buck-boost LED driver passes CISPR 25 Class 5 EMI

Figure 2: Efficiency of LED driver solution in Figure 1. Measurements made using 16V, 1.5A, demonstration circuit DC2575A LED driver with and without optional EMI components

Figure 3: LT8391A demonstration circuit DC2575A passes CISPR 25 Class 5 automotive radiated EMI

Figure 3A Figure 3B

Figure 3DFigure 3C

2524




high power at low VIN possible.

The LT8391A in-cludes the latest PWM dimming features and open LED fault protec-tion. This synchro-nous buck-boost regulates current through a string of LEDs with a voltage that may or may not lie within the input voltage range, such as the 9V–16V car battery or a truck battery (18V–32V). It can run down to 4.0V cold crank input and can withstand up to 60V input transients. The LT8391A pro-vides up to 2000:1 PWM dimming ratio at 120Hz and can use its internal PWM dimming generator for up to 128:1 ac-curate dimming ratio without the need for an externally sup-plied PWM clock.

Cispr 25 EMI for automotive applicationsThe 2MHz LT8391A LED driver in Figure 1 is designed for automotive headlights. It uses AEC-Q100 components and meets CISPR 25 Class 5 radiated EMI standards. Spread spectrum frequency modulation (SSFM) reduces EMI, and also runs

flicker-free simulta-neously with PWM dimming as shown in Figure 7. Its small size is highlighted by its small inductor and especially small input and output EMI filters. Large LC filters are not needed for 2MHz converters and only small ferrite beads are used for high frequency EMI reduc-tion.

Automotive EMI requirements are not easily met by high power converters. High power switches and inductors, placed on large PCBs next to large capacitors can create unde-sirable hot loops, especially when a large sense resistor is included. The unique LT8391A buck-boost architecture removes the sense

resistor from both the buck and boost switch-pair hot loops, en-abling low EMI.

Figures 3 and 4 show measured EMI of the 24W LED driver of Figure 1. Despite this con-troller’s 2MHz operating frequency and 24W of power, this buck-boost passes CISPR 25 Class 5 radiated and conducted EMI. Class 5 is the most stringent requirement and the goal of most automotive EMI testing. Converters that cannot pass Class 5 EMI either get de-signed out of automotive circuits or must be encased in large metallic EMI shields. Even if the bulkiness of the shield does not create assembly issues, adding them is costly.

Figure 4: LT8391A demonstration circuit DC2575A passes CISPR 25 Class 5 automotive conducted EMI

Figure 5: LT8391A multi-beam LED headlight cluster solution for low, high, and DRL lights

Figure 4BFigure 4A

Buck-boost for multi-beam applicationsLED headlight clusters can be both innovative and artistically creative. High beams and low beams can be wrapped up with nifty and distinc-tive daytime running lights (DRL). Because the daytime running lights are only needed when high and low beams are off, a single LED driver can be used to power either the high and low beam LEDs or the daytime running lights. This only works if the LED driver has a flexible input-to-output ratio and can both step-up and step-down the input-to-output voltage. A buck-boost design satisfies this re-quirement.

The multi-beam LT8391A buck-

boost LED driver in Figure 5 can drive LED string voltages ranging from 3V to 34V. This enables it to drive both a low beam string and create a high beam by adding LEDs to the low beam string. The same driver switches over and drives a higher voltage, yet lower current, DRL. Switching from low-beam-only LEDs to a low/high beam combo string gen-erates no spike on the output voltage or LED current as shown in Figure 6a. The LT8391A can

transition between boost, 4-switch buck-boost, and buck re-gions of operation smoothly. Changing from a small number of LEDs to a high number of LEDs without an LED spike can be challenging for a converter, but this multi-beam circuit does this with ease. Switching back from high and low beams to just low beams is also very clean, without any harmful LED spikes, as shown in Figure 6b.

The same is true when switch-ing to and from the DRL string. Figure 6c demonstrates how the low beam is turned off and the DRL is smoothly connected to the output capacitor. Even the LED current is changed from 1A

Figure 6: Waveforms show smooth switchover between high + low, low and DRL LED strings for the LT8391A multi-beam application in Figure 5.

Figure 6A: low beam to high + low beam

Figure 6C: low beam to DRL

Figure 6B: high + low beam to low beam

Figure 6D: DRL 10% PWM to low beam

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(high and low beams) to 700mA (8 LEDs DRL) without any issues. Other trim or signal LEDs can be added in as well, and the DRL can be blinked as a signal light. Figure 6d shows how the DRL can be PWM dimmed with the in-ternally set PWM generator and then switched over smoothly to low beams when darkness falls.

Automotive environments require robust solutions in the face of short-circuits and open LEDs. Short- and open-circuit conditions are safely handled by the multi-

beam solution shown in Figure 6, and report-ed via the converter’s

fault flag.

FE and QFN packages fit tight spotsThe LT8391A is available in a 4mm × 5mm 28-lead QFN for small size and a 28-lead TSSOP FE package for automotive designs. Both packages have thermally enhanced GND pads for power dissipation of the internal INTVCC LDO from higher voltages.

The internal LDO INTVCC regula-tor of these converters can handle driving four synchro-nous MOS-

Figure 7: Compact solution: 2MHz demonstration circuit DC2575A, featuring LT8391A, drives 16V LEDs at 1.5A

Table 1: High power, high efficiency synchronous buck-boost controllers for automotive power solutions

FETs at 2MHz with about 15nC gate charge. The small size of the LT8391A FE 2MHz 16V, 1.5A demonstration circuit (DC2575A, based on the design of Figure 1) is shown in Figure 7. Only a single 5mm × 5mm inductor is neces-sary for this high power, versatile application.

ConclusionThe LT8391A 2MHz, 60V buck-boost LED driver controller pow-ers LED strings in automo-tive headlights. Its features include its low EMI 4-switch architecture and spread spectrum frequency modu-lation for meeting CISPR 25 Class 5 EMI requirements. The unique,

high switching frequency allows it to operate above the AM band, requiring very little EMI filter-ing. Its small size and versatility en-able use in headlight cluster LED strings of a variety of volt-ages and currents.

Analog Deviceswww.analog.comFigure 8BFigure 8A

Figure 8: PWM dimming using internal and external PWM options; 1% and 0.05%,

The Switches Behind Today’s LED Lighting Applications

By: Mike Bolduc, Global Marketing Manager, Industrial & Medical Segments, C&K

The impact of LED lighting is far-reaching, and its use cases are diverse.

The global LED lighting market is undergoing a drastic change, propelled by the

exponential urban expansion expected over the coming years, and the drive towards increased energy efficiency. In fact, the global LED lighting market is expected to surpass $100 Billion by the end of 2024, according to new data from Renub Research. And it’s no surprise: LEDs offer longer lifetimes, lower energy consumption and reduced maintenance expenses when compared with other lighting technologies.

As such, the impact of LED lighting is far-reaching, and its use cases are diverse. Applications from smart cities to industries such as retail are beginning to feel the positive impact of more efficient lighting. For example, LEDs are quickly becoming the dominant source of lighting in cities around the world. From 2017 to 2027, global investment in LED street lighting is expected to be $53.6 billion, according to Research and Markets. In fact, Walmart has reported saving more than $100

million in energy costs after installing more than 1.5 million LED light fixtures at its stores, according to a recent article in Electric Light & Power.

From residential to commercial, indoor, outdoor and even portable lighting systems such as those used at construction sites or during emergency response, lighting applications are only as useful as the hardware that powers them. Early LED adoption was simply about switching out bulbs for energy savings. Companies today however want to take advantage of the full capabilities that LED products have to offer. As a result, attention to design features on the light engines, controllers, luminaires and fixtures is critical to the style and functionality of the end product. Described below are some of today’s most important LED lighting applications, along with the electro-mechanical switches found in them and some considerations design engineers should keep in mind as they light the way forward.

Residential and Commercial

Buildings LED lighting systems for residential and commercial buildings must facilitate eco-friendly initiatives, perform in high-use and often harsh environments and be aesthetically pleasing. Common LED system components including controllers, luminaires and fixtures, operator consoles and energy management systems must be designed with a combination of performance and customer appeal requirements in mind.

Residential systems typically place a premium on aesthetic appeal and ease of use to the end customer. As a result, the components used in these devices must perform reliably but also have features which convey an image of quality and performance to the user. Consider the various wall switches and consoles used to operate the dimmers and timers found in most residential lighting systems. In addition to miniature form factor and life cycle requirements, the switches used in these products often have specific haptic (sound and



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series are commonly used for voltage selection. A stainless-steel shaft and IP67 sealed internal components allow this switch to stand up to outdoor environments for many years.

Similarly, push button switches are commonly found on the control panels of potable LED lights used for sporting events, construction sites or emergency situations. These buttons can be illuminated or non-illuminated but typically need to be IP67 or epoxy sealed for harsh environment performance. C&K’s AP and 8060 series are typically examples.

Durability is another

differentiator when it comes to indoor versus outdoor lighting. While maintenance indoors can be as simple as switching a low-hanging light bulb or reconfiguring an easily-accessible wall panel, performing maintenance or repairs on outdoor lighting products can be difficult and time-consuming, given the location and accessibility of many of these devices. Designing products which are maintenance-free or that perform reliably for many years is of significant benefit to the end user. Materials, contact system design, over-travel, over-force protection and durability are all key considerations to

have in mind when determining the ability of the switch to work properly and remain efficient over the years. Switch selection for LED lighting applications can be a challenge, whether it’s for a street light or a light fixture in your kitchen. Therefore, it’s important for engineers to keep both energy efficiency and other factors such as reliability, durability, product lifecycle and the environment it will operate in – indoor, outdoor, commercial, or residential – top of mind when creating the LED lighting systems of the future.

C&K Componentshttps://www.ckswitches.com

feel) requirements meant to create a perception of quality to the customer.

C&K’s KSC and KMR series tact switches have small footprints and offer a number of options – including tunable haptics and various actuator heights and materials – which enable product designers to develop the perfect experience for the end user.

Commercial LED applications can range from luminaires and fixtures used for accent lighting in a restaurant or retail store, to strobe lights used in factories for machine vision systems, and even to digital signs and message boards found in a local mall. Each of these applications places different requirements on the hardware such as switches used to configure and operate the device.

Commercial luminaires and fixtures may rely on a simple toggle or rocker switch for manual on/off control, however these switches need to be robust enough to stand up to commercial use. Strobe controllers used in LED lighting for machine vision systems typically utilize small tact switches for setup and control. The switches used generally need to be sealed in order to last for years in a factory environment. Commercial buildings such as movies theatres and malls rely on LED

emergency lighting in the event of a power outage. DIP switches are commonly used on these products to configure various settings and should meet the same harsh environment performance requirements as the fixture itself.Various tact, DIP and toggle switches are also found inside digital message boards to configure the output or change the display.

Despite the different aesthetic and operational priorities of commercial and residential applications, tact, DIP, and toggle switches can offer a reliable solution for making sure buildings remain functional, safe and efficient when it comes to the LED lighting applications within.

Outdoor LED LightingEfficient and powerful LED lighting is also used to power a number of critical outdoor applications in our world today. Imagine a highway or parking lot with no lights, a construction site at night with no roadwork signs or a crash site with not enough light for emergency crews to do their job safely? Typical outdoor LED applications include roadway and landscape lighting, sports or stadium lighting, speed limit alerts and digital signage used in railways, bus stations and intelligent transportation systems. Most of these devices utilize hardware such as electro-

mechanical switches for on/off and menu control as well as to configure the output of the light controllers.

While there are many types of switches used in LED lighting applications – the aforementioned tact switches, as well as toggle, DIP, pushbutton and rotary switches – any used in outdoor products must be more robust and able to withstand more challenging conditions than their indoor counterparts. Knowing that environmental requirements and other critical performance factors need to be taken into consideration will have an impact on the lighting application and component selection from the design phase.

Understanding where and how the lighting application will be used, the temperature range and whether or not it will be subjected to corrosive elements like salt, dust or moisture, is critical to incorporating the proper switching components. Better protection and more robust components lead to improved performance and reliability, as well as a longer product lifecycle of the end device.

For example, LED street lights frequently use constant current or constant voltage drivers which can be adjusted based on the light output needs of the application. Rotary switches, such as C&K’s M

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The future of microLED displays using next-generation technologies

By: Myles Blake, Marketing Director, Plessey Semiconductors

MicroLEDs offer an emissive display technology that delivers high contrast, high speed and a wide viewing angle current without high power consumption

MicroLEDs (micro-light-emitting diodes) are an emerging display

technology that, as the name implies, use very small LEDs for pixels. Much the same as any other current display technology, it combines red, green and blue sub-pixels to reproduce a colour. Although there are currently no microLED displays in mass production today, there is a massive opportunity for the technology to penetrate major display markets and replace incumbent LCD and OLED (organic light-emitting diode) technologies in a wide range of applications, from HDTVs to smartphones and wearables such as smart watches, and head-up displays (HUDs) and virtual reality (VR) and augmented reality (AR) headsets. According to research consultancy Yole Développement, the market for microLED displays could reach up to 330 million units by 2025. However, many development challenges remain before microLEDs can fully realise their potential.

Display technologiesLike OLEDs, microLEDs offer an emissive display technology that delivers high contrast, high speed and a wide viewing angle current. However, OLED technology is power hungry and does not offer high levels of brightness – for example, users will often find it difficult to read the screen of a smartphone or tablet in high ambient light. Whereas MicroLEDs offer the potential for significantly higher brightness, as well as enhanced robustness and longer lifetime. In addition, a major advantage is greater efficiency, which can mean significantly reduced

power consumption, making the technology ideal for battery powered products.

MicroLEDs are also ideal for small form factor products such as head-mounted displays, making VR and AR a major application opportunity. However, in these types of applications there are difficulties concerning waveguide interfacing, as LEDs are typically coupled with a waveguide to deliver the image, in contrast to a smartwatch for example, which has a directly viewable display. Coupling a waveguide is a very lossy process: only 7% of the light entering an

HUD is usable by a viewer, with 93% being lost. Although this is perhaps acceptable for relatively simple applications, such as displaying vehicle speed or satnav information, it is unsuited to more complex images.

Importantly, microLEDs start off as a significantly brighter source, offering brightness three or four orders of magnitude higher than OLEDs, which are capable of delivering around 1000 Nits (cd/m2), whereas microLEDs offer hundreds of thousands of Nits for the equivalent power consumption. This is a major advantage in devices from HUDs to VR and AR products, where waveguides are commonly used to place images in a headset or in a pair of glasses right in front of the eye. The vision for microLEDs could mean the transformation from a typical bulky and power-hungry VR headset to something more akin to a pair of glasses. Alternatively, it could mean charging every month rather than every two days for a product in which the display is largely responsible for the majority of the power consumption.

ManufacturingA major challenge existing today for the manufacture of microLED displays is placement of gallium nitride (GaN) LEDs onto a substrate. One notable approach in the industry is the development of GaN-on-sapphire technology, but this

technology is not suited to a monolithic approach and is currently achieved using pick-and-place equipment. This involves the individual placement of every LED on a pitch of less than 50μm, which requires new and expensive equipment that is subject to productivity issues. However, with increasing pixel density for displays, the LED pitch becomes ever smaller and pick-and-place becomes less feasible both commercially and technically. There is much development in the industry in pick-and-place manufacturing technology, with the emphasis on massively parallel processing equipment that can simultaneously pick up hundreds or even thousands of LEDs from the donor wafer and then attach them to a backplane, but clearly this means significant capital expenditure. Another issue with increasing pixel density is that discrete LEDs have a finite size, bringing issues of physical stability as well as alignment. The human eye is most unforgiving – it is

very good at picking up distorted images or misalignment from pixel to pixel. Certainly, massively parallel pick-and-place production can help, but it must be recognised that the spacing between each individual LED will still be limited by its size.

GaN-on-sapphire technology typically targets high-volume applications such as smartphones or smart watches that might typically offer 400dpi displays, based on an 80-micron pixel pitch. But moving to VR, AR or merged-reality applications means the pixel pitch needs to be reduced to 40 or 20 microns, or even as low as 10 to 15 microns. It is beyond the ability of pick-and-place machinery to place pixels with any kind of alignment accuracy.

In order to address cost and yield considerations, there will also be a requirement to build micro LED arrays on larger substrates. GaN-on-Sapphire substrates exist up to 6”, but the costs to increase sapphire

Figure 1: Brightness in Daylight

Figure 2: AR Glasses



substrates to 200mm will result in very expensive substrates. In addition to the availability of large GaN-on-sapphire wafers, another point is that it is very difficult to scale up the size of an LED array using GaN-on-sapphire. A significant advantage of an alternative technology – GaN-on-Silicon (Si) – is the ability to make much larger LED emitters. One major reason is that GaN-on-Si is an inherently surface-emitting technology, whereas GaN-on-sapphire is an inherently volume-emitting technology – emitting from all four sides of the device as well as the surface. In the development of advanced display technologies, it will be necessary to resolve individual pixels and colours, and a volume-emitting LED delivers a significant amount of cross-talk

from individual pixels, resulting in a loss of contrast for an end display.

Monolithic approachAll this leads to the construction of a single hybridised monolithic array, which is to say, building GaN microLEDs on top of, and interconnected with, a CMOS silicon thin-film-transistor backplane with no requirement for pick-and-place. Very importantly, this approach supports the integration of a standard CMOS circuitry array that delivers charge to the LEDs, providing the necessary addressing and driving of microLED displays. In addition, this approach can enable the close integration of high-performance GPUs, all of which can be carried out using standard CMOS manufacturing

methods. A major point is manufacturing scalability – monolithic GaN-on-Si is very easily scalable to 200mm wafers and beyond, which will be critical for cost and yield.

Certainly, monolithic microLED manufacturing is a nascent technology and many challenges remain. Not least of these is connected with colourisation issues; further research is required into the properties of phosphor, as well as other potential materials, for the conversion of blue light into green and red, especially when making a 5- or 10-micron pixel.

Overall, moving to a monolithic process will enable smaller and higher-resolution displays for a range of applications, and GaN-on-silicon is the only technology that can deliver the required levels of scalability and performance. It offers higher luminosity than OLED and also better thermal conductivity than sapphire and is becoming widely acknowledged as the best bet to deliver the next generation of high-resolution and high-luminance displays.

Developing the right technologies Plessey Semiconductors is a leading developer of award-winning optoelectronic technology solutions, with extensive expertise in LED technologies. For the past five years, the company has been

developing highly efficient and robust products that target the high-power LED lighting market, based on technology gained in 2012 from the company’s acquisition of CamGaN, a spin-out from Cambridge University. Prior to this, Plessey was a leading European foundry for CMOS image sensor production.

Experience gained in these markets provides the company with a significant head-start in knowing how to design the backplane to be used with a microLED display, especially in terms of understanding yield issues. In addition, the underlying principles of LED displays and image sensor technologies have much in common: the light-sensing component of the CMOS sensor is essentially replaced with the light-emitting component of the microLED. The principles in driving and addressing LEDs are similar and the clocking of data is also analogue – in for LEDs and out for image sensors. In addition, many functional blocks are similar, if not entirely the same. This experience, in conjunction the development of significant range of technological IP, is enabling the move to the next step in the company’s evolution: Plessey is to license out its production-ready GaN-on-Si technology platform to potential microLED display makers.

The company has made

several important steps in the development of microLED technology, which is already offering LED performance that is equivalent to incumbent technologies in general lighting applications. The company has already demonstrated its capabilities with the development of 100- and 20-micron pitch LED arrays for a print-head project with LumeJet, based on blue microLEDs and offering a density of 400 pixels per inch (ppi). A 100-micron microLED demonstrator already exists, and Plessey will be offering a 20-micron version in 2018. Technology demonstrators at 100 microns are now also in development from Plessey for red and green microLEDs. The company is already deep into a development programme to address the challenges for sub-10-micron pixel applications.

While many challenges still exist, the monolithic GaN-on-Si approach for microLED technology is not subject to the technical and commercial productivity issues associated with pick-and-place equipment. Overall, it can deliver the high-volume and cost-effective mass manufacturing capability necessary for this disruptive technology to make the most of the significant opportunities available today in a range of display markets.

Plessey Semiconductorwww.plesseysemiconductors.com

Figure 3: Product Demonstrator



Smart yet frugal - energy saving next generation lighting

By: James Lee, Lighting Segment Marketing, ON Semiconductor

How LEDs can go beyond the replacement of conventional lighting

Lighting is important to us – a fact borne out by an estimate from the US Energy Information

Administration that we use the same amount of energy to light our homes (129 Billion kWh – 9% of total consumption) as the total amount we use to wash and dry our clothes, use our computers and cook.

However, much of this energy is wasted, as incandescent light bulbs are notoriously inefficient, converting around just 5% of their output to light with the remainder becoming heat. By implementing more efficient solutions based around LED lighting technologies that are closer to 50% efficient, it is estimated that the electricity used for lighting could be reduced by around 40% by 2030.

Smart LED lighting is the way to reduce energy consumption and closely match lighting provision and configuration to real requirements for both medium and high power applications in offices, factories and public buildings.

While falling LED prices are

key to stimulating adoption, there are increasingly stringent regulations for standby power and efficiency in lighting being imposed by governments as the environmental impact of not addressing the historical inefficiencies and wastefulness of traditional lighting are widely recognized.

LED lighting offers fundamental improvements versus incandescent lighting in terms of using less power and outputting that power as light as opposed to heat. However, it is now important to couple solid-state lighting technology with innovative driver solutions to meet regulatory demands

and deliver effective power management and features such as dimming.

The market for LED lightingThe growth of construction is a significant driver for the growth of LED lighting and, while this represents the major portion of the market according to research firm Research and Markets, retrofit is also a significant driver. Indeed, they believe that retrofit will be the fastest growing portion until 2023.

Indoor lighting (including homes, factories, public buildings and offices) is the largest revenue sector of the market but outdoor lighting will be the fastest growing with the biggest driver being the improvement of lighting on roads as local authorities seek to improve visibility and control costs at the same time.

LEDinside, a division of TrendForce, estimated the LED lighting market to be worth US$33.1 billion in 2017 with the penetration rate of LED lighting reaching 52%. According to LEDinside, LED lighting accounts for 23% of all lighting in Europe, which is the highest for any region. The USA and China were second and third respectively and Asia-Pacific is expected to be the fastest growing region, presumably due to the significant number of infrastructure projects.

Smart solutions for frugal lightingUnlike incandescent bulbs which

can just be connected to a mains supply, LEDs are low voltage devices that require a power supply that can provide either a constant voltage (CV) or constant current (CC) supply. These power supplies have a material impact on the overall efficiency of the lighting solution and are, therefore, coming under as much scrutiny as the LEDs themselves – especially with regard to standby power.

While a very significant proportion of the market for LEDs is to facilitate (or replace) traditional lighting, the versatility and relatively small size of LEDs is allowing them to be used in places where it was just not possible to implement incandescent solutions. However, fitting the LEDs and associated power supply into these small, tight spaces demands highly efficient, compact power supply designs.

One challenge with LEDs has been to deliver dimming capabilities across the whole brightness

range while maintaining a good quality of light. Many solutions introduce ‘flicker’ which can cause challenges, especially in environments where cameras are used for sensing, such as factories and, soon, the in-vehicle systems on our roads.

Not only are designers being challenged to deliver highly efficient, widely dimmable, compact and flicker-free lighting solutions, consumers and installers are expecting to see similar price reductions in the power supplies as they are currently seeing with the LEDs themselves.

The 25-100W sector is one of the most common power points for LED lighting solutions. Here, a common approach is to use a two-stage conversion with an initial reduction and regulation of the mains voltage using a Power Factor Correction (PFC) stage that provides a constant voltage as well as control signals (including dimming control) to a microcontroller (MCU).

Figure 2: The FL7740 and FL7760 are a complete dimmable solution for modern LED lighting

Figure 1: A two-stage conversion is the most common approach in mid-power lighting solutions

The second stage converts the regulated voltage to supply current to the LEDs, taking into account any dimming requirement from the MCU.

However, in order to meet these relatively complex requirements for modern LED lighting, innovative semiconductor control solutions are required. ON Semiconductor has leveraged its knowledge in developing energy efficient power solutions to deliver a pair of ICs that make a material step forward in enabling frugal lighting solutions that meet the needs of today’s competitive market.

Our FL7740 (primary side regulation and PFC) and FL7760 (DC-DC Buck) deliver a simplified

topology and reduced size and cost through a constrained BOM. Used together, they provide precise, CV/CC regulation and support for both analog and PWM dimming.

The FL7740 requires few external components and consumes less than 0.15W in standby mode, which is a critical specification for smart lighting, allowing regulations such as Energy Star to be met with ease.

The FL7760 offers a wide analog dimming range of 5 to 100% which, for the first time, makes the use of analog dimming a viable option for solid-state lighting designers. It also supports PWM dimming from 0 to 100%, though inherent issues of flicker and

audible noise make this somewhat less desirable. However, the FL7760 is unique in its ability to seamlessly combine analog and PWM dimming to cover the 0 to 100% range without flicker or audible noise – a major step forward.

With advanced semiconductor technologies such as these making LED-based smart lighting not only viable, but straightforward to implement, more efficient, smaller and lower cost, the potential to improve working and living environments whilst saving tens of billions of kWh is a relatively near-term reality.

On Semiconductorhttp://www.onsemi.com


Horticulture lighting drives plant growth

By: Svenja Mahler, Product Sales Manager Opto (LED IR), Rutronik

How low-cost LED lighting promotes the optimal growth of plants

The market for light-emitting diodes (LEDs) has been experiencing

continuous growth for several years. The reasons for this include, for instance, the low costs of the LEDs, whose energy efficiency and capabilities, brightness, and color scheme can be adapted individually to the respective requirements. In addition, drivers enable a simple method, usually via plug&play, for targeted control of the LEDs.

Today, more than half of the world’s population lives in cities, and this trend looks set to continue. When it comes to providing people in so-called mega cities with a sufficient amount of healthy food, conventional methods of agriculture will soon reach their limits. A possible solution is horticulture lighting.

Horticulture lighting refers to the illumination of plants with artificial light to achieve both faster and targeted growth; specifically aimed, for example, at bud development and fruit ripening. Light stimulates

photosynthesis and is thus decisive for plant growth. However, the light must provide the correct spectral range. Different wavelengths are important for the growth, shape, development, and blossoming of the plant. For instance, if red LEDs with a wavelength of 660 nm are used for tomatoes, it has a positive effect on the harvest, especially on the number of fruit. Conversely, exposing cucumbers to blue light with 455 nm slows down growth, while a blue wavelength of 470 nm results in a greater leaf area and

fresh and dry shoot biomass. The time period during which the plants are exposed to light is also significant for horticulture lighting. The ‘natural daytime’ can thus be extended with the aid of artificial light and results in stronger growth and increased bud development.

Furthermore, there is a range of options for arranging the lights to the plants. The standard method is ‘top lighting’ where the LEDs hang above the plants. Due to the low heat development of LEDs, the distance between

Figure 1: Horticulture Facility





is available in eight colors, ranging from 450 nm (deep blue) to 730 nm (far red), which represent the most reliable wavelengths in terms of plant growth. Everlight Electronics also provides customers with a wide range of products for the horticulture lighting sector and is therefore an ideal addition to Rutronik’s portfolio.

However, each LED has to be supplied with the respective energy. Infineon Technologies is a technology leader in the field of power management and offers an extensive selection of analog and digital LED drivers, microcontrollers, MOSFETs, and DimmingICs for horticulture lighting solutions. The portfolio of Infineon Technologies addresses all the standard topologies for single string < 100 W, single string > 100 W, and multi-string applications.

Controller for monochrome LEDsInfineon’s configurable XDPL8105 digital, single-stage flyback controller provides a perfect solution for controlling the Oslon-SSL-Color family, especially when controlling uni-color LEDs below 100 W. Figure 3 shows an example of the circuit diagram for the XDPL8105 in single-stage flyback CC topology. The XDPL8105 is a digital AC/DC converter with flyback function that enables isolated dimming

from 0 to 10 V. Yet another advantage is intelligent thermal management.

The CDM10V driver can be individually configured once, thus resulting in a plethora of versatile applications. Infineon delivers pre-configured components, but configuration can also be performed by each customer individually. The main benefits of the CDM10V are the programming option, the reduced space as a result of the 6-pin SOT package, and the dimming function (0-10 V).

Precise control of multicolor LEDsIf plants are exposed to light from multi-colored LED strips, it requires precise control to ensure the light is provided at the correct wavelength. To achieve this goal, suppliers such as Infineon or Diodes supply an array of solutions.

One example is the ICL5101 AC-DC LED driver IC from Infineon in combination with the 700 V/800 V CoolMOS P7. This PFC+LLC solution offers, above all, advantages due to very low THD (Total Harmonic Distortion) over a wide load range.

Infineon’s ILD6150 DC-DC LED driver, in conjunction with the XMC1300 microcontroller, complements this multi-string solution by supporting, among other things, connectivity, e.g. via DALI and DMX, as well as the

the light source and the plant can be kept to a minimum. And the racks can thus contain a greater number of levels. Moreover, LEDs also enable ‘inter-lighting’. In this case, the lights are positioned in between the plants, which, compared to

‘top lighting’, helps to reduce shading. This ensures that smaller plants are exposed to sufficient light, too.

Thanks to new LED technologies, it is possible to maximize plant exposure to the precise

wavelength that promotes photosynthesis and optimum growth. Additionally, being able to influence the exposure period and benefiting from a flexible arrangement of the LEDs are strong arguments in favor of the use of LED lighting for plant growth. In the sector of horticulture lighting, the OSLON-SSL product range from OSRAM Opto Semiconductors offers an extensive portfolio of high-performance LEDs with low thermal resistivity. The robust ceramic package is ideal for the conditions inside greenhouses. The OSLON-SSL-Colors family

Figure 2: PFC Solution enabling very BOM and THD over wide power range

Figure 3: OSRAM LED String

Figure 4: ORSAM Single Color String Topology

integration of sensory equipment. Furthermore, the XMC1300 supports automatic exponential dimming and linear intensity changes and ensures brightness and color transitions appear natural to the human eye. Further, the automatic brightness control enables flicker-free dimming, also for a dimming level of below 0.1%.

From a financial perspective, the use of LEDs offers various advantages compared to conventional lighting options. For a start, LEDs do not burn out like traditional light bulbs but simply experience minimum lumen depreciation over time. While light bulbs are liable to fail on average after just one year, top grade LEDs can now be operated for more than 50,000 hours (depending on the type of application). The increased lifetime additionally ensures high reliability. Further, energy can be saved through effective and efficient control. Horticulture lighting looks set to grow in the coming years thanks to new LED technologies and intelligent control units.

Rutronik recognized this trend at an early stage and already offers a wide range of products that can be used for horticulture lighting. Heatsinks, connectors, cables, MOSFETs, diodes, and microcontrollers are just a few examples from Rutronik’s extensive portfolio.

Rutronikwww.rutronik.com


POWER SYSTEMS DESIGNFINALthought

By: Ally Winning, European Editor, PSD

Manufacturing logistics are key to productivity

O ne theme that I’ve

seen cropping up

quite regularly from

manufacturers

recently is a bigger emphasis on

logistics. Logistics may not initially

seem a likely way to increase

efficiency on the factory floor, but

to manufacturers who have pruned

and tweaked processes elsewhere,

concentrating on logistics may be the

last of the low hanging fruit before

making serious changes to business

practises. The process of digitising

and optimising logistics and the

supply chain can make a big difference

to many companies immediately.

The subject was brought to my

mind during a recent working trip

to Germany when it came up on

two different occasions. It initially

materialised at the Hanover Messe

preview when Dr. Jochen Köckler,

Chairman of the Managing Board

at Deutsche Messe, was detailing

why the CeMAT exhibition had been

brought back into the main Messe

event. Today’s working practices rely

on a lean philosophy that demands

the elimination of waste and the

integration of manufacturing, logistics

and the supply chain are integral to its

success.

CeMAT’s theme this year is "Connected

Supply Chain Solutions" and its stated

aim is to “drive forward the digital

integration and networking of value-

adding and supply chains”. The theme

highlights that the optimisation of the

supply chain is not really a problem

that can be accomplished alone by

a single company. It must work in

concert with its partners to make the

complete supply chain more efficient

as a whole. I’m sure CeMAT will prove

an interesting event for anyone that

is visiting the main show and the

innovation on show will provide some

inspiration for the future.

The second event that concerned

logistics was a visit to HARTING’s

new high-tech distribution centre.

HARTING’s aim for the new facility

is to provide customers with a

quicker and more efficient fulfilment

channel. As time pressure increases in

business, engineers don’t want to wait

for the components that they need for

their new products. If they can’t buy

immediately from a preferred supplier,

they will go elsewhere to someone who

can. HARTING has adopted much

of the innovation that will be seen at

CeMAT into the facility to streamline

its operation and get orders out the

door quicker. The company has a

vertical view of the industry at times,

and as well as producing connectors,

it designs and manufactures the

machines that make those connectors.

It will also incorporate its MICA

embedded platform to help run the

distribution centre when it opens next

year, which is as good of an example

as possible of how logistics and

manufacture are inextricably linked in

Industry 4.0 production.

Germany is an interesting place to visit

manufacturers. Despite a somewhat

stuffy, conservative reputation, the

companies there, especially the

small and medium sized ones, are

leading the way in the development

and implementation of tomorrow’s

manufacturing and they seem to have

their eyes on logistics as an integral

part of the solution.

PSD


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March 2018 - Power Systems Design

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