It’s often said that we can’t determine where we are going without an understanding of where we have been. While today’s market is rapidly becoming inundated with LED-based products, it is not as new to the world as you may think. Below we will take a look at the many developments and people who have gotten us to where we are today.

1907

Henry J. Round, an assistant to Marconi in England and the chief of Marconi Research added a 24-line note in Electrical World describing a “bright glow” that eminated from a carborundum diode. This was the first reported discovery, not of a LED but the phenomenon of electroluminescence.

1927

The first development of an actual LED-type device was discovered by a self-educated Inventor named Oleg Vladimirovich. He wrote a series of papers from 1924-1930 that provided a comprehensive study of the LED and its possible applications. He had observed light emission from a zinc oxide and silicon crystal rectifier diode that he was using in a radio receiver. He noted a glowing light that was produced when current ran through them.

He called the process “Inverse Photo-Electric Effect” and received a patent relay in 1927.

The basis of his patent was the following:

“The proposed invention uses the known phenomenon of luminescence of a carborundum detector and consists of the use of such a detector in an optical relay for the purpose of fast telegraphic and

telephone communication, transmission of images and other applications when a light luminescence contact point is used as the light source connected directly to a circuit of modulated current.”

1955

Rubin Braunstein from the radio Corporation of America reported on an infrared emission from gallium aresenide (GaAs) and other semi-conductor alloys. This was the beginning of today’s LED material design.

1961

Americans Experimenters Robert Biard and Gary Pittman from Texas Instruments applied for and received the first patent for an infrared LED.

1962

Nick Holonyak developed the first practical, visible spectrum LED while working at General Electric Company. Due to this, Honolyak is viewed as the “Father of the Light Emitting Diode.”

1968

Hewlett Packard introduces the first cost-effective red LEDs. The revolution then takes off as LEDs become widely used for alphanumeric displays and a wide variety of indicator and signaling applications.

1970

Commercially successful LEDs started being manufactured by Fairfield Electronics at a cost of less than five cents per device. They used compound semi-conductor chips and used the ‘planar process’ of development invented by Dr. Jean Hoerni.

1980′s

A wide array of LED developments led to blue, ultraviolet, RBG and white LEDs.

1995

Alberto Barbieri from the Cardiff University lab developed a transparent contact made of indium tin oxide (ITO) on an (AlGaInP/GaAs) LED. This device demonstrated a highly efficient and bright LED design that is now used in many high efficiency LED designs.

2006

The Millenium Technology Prize was awarded to Nakmura for the first lone LED device that appears as a white light. It employs a “YAG” phosphor coating to mix yellow down converted light with blue light to produce a light that appears white.

2008

Luminous efficacy of 300 lumens of visible light per watt of radiation and warm light emission was achieved using nanocrystals.

2009

A new process for growing gallium nitrade (GaN) on silicon was reported. This development will allow costs to be reduced by approximately 90%.

The future of LED development is progressing and improving at rapid rates. It’s safe to say that within the next decade, the majority of lighting applications, whether architectural, equipment-based, signaling, display-based and more will be produced and operated with LED devices.

To make sure your next, best idea is set to grow with the times, contact VCC today to order the latest and greatest LEDs to use in your design.

Today’s PCB driven devices are becoming smaller, resulting in less area for cooling of PCB components and an increased amount of heat per square inch. For every 10 degrees Celsius rise in temperature, the device rate of failure doubles if the wasted heat is not removed. Thermally conscious systems determine if the design will function or potentially fail.

PCB design decisions can be made and implemented from the start to optimize product performance, reliability and delivery schedules. Several techniques that can be used to assist in heat dissipation are listed below:

• Strategic PCB Layout – Strategic PCB layouts should be used whether your device is small or large to increase reliability and performance. High power components should be placed in such a way that the maximum amount of board space possible will separate them from each other. This allows for the most heat dissipation space between components.

• Maximize PCB Material and Construction – When selecting the PCB material and construction, some elements can be chosen that will increase the heath dissipation of the entire board. Thermal performance increases with the increase of copper in the PCB construction. To take advantage of this fact, the design should include the largest possible number and thickness of copper ground layers in the design.

• Dedicated Heat Spreading Plane – Utilizing a cold plate or heat spreading plane attached to the underside of the PCB offers a thermal connection to the devices that allows for much greater cooling.

• Increase Possible Heat Paths – Increasing the number of possible heat dissipation paths will improve the heat reduction of the complete board. As devices become smaller, it becomes more important to take advantage of every available thermal control opportunity. Thermal vias will help carry heat down to the inner board layers and underside of the board. Wider traces leading away from high power devices will provide additional heat paths for dissipation and using metal PCB stiffening plates that are connected to the heat-spreading plane will all provide more effective cooling.

• Addition of Heat Sinks and Fans – For systems where the simpler design changes above do not dissipate enough heat, add a heat sink or fan and heat sink combination provides direct cooling of critical high power components.

• Larger PCB Housing – When it’s possible to use a larger PCB housing, the ambient air surrounding the PCB permits heat to escape into the enclosure.

• Venting – Strategically placing of vents within the PCB enclosure will maximize the natural air current flow and allows designers to take advantage of ambient air moving over the PCB to improve cooling.

• Enclosure Fan – For more extreme heat conditions, an enclosure fan can be added to significantly increase air flow and lower the temperature of critical devices.

Good thermal design can make the difference between a successful product and one that is prone to failure. For PCB components and advice, VCC representatives are always available to handle a variety of questions and propose solutions for thermal PCB design parameters. Contact VCC today fore more information.

LED prominence and growth is only a surprise to those who have been in a deep slumber for the last ten years. The number of applications where LEDs are in use is endless. Below we will cover some of the most prominent LED applications, both indoors and outdoors, and also typical challenges and solutions for these installations.

Indoor

Applications: Indoor LED applications can range from commonly used pieces of equipment such as microwaves, computers and temperature control panels to much more complicated systems such as security, power conversion, signage and more. To list all the possibilities would take more space than I have to write or you have to read. The only limit to the number of ways LEDs can be implemented is the imagination of the Engineer and/or designer.

Outdoor

Applications: Outdoor LED applications, much like the indoor scenario are essentially endless. Most automobiles produced today have LEDs in use everywhere from your tail light to the console and as your driving, the traffic signals, retail signage and even the side-of-the-road construction messages are all produced with the support of LED circuitry. The security systems of the homes and businesses you pass are utilizing LEDs as are the planes flying above your head. Virtually every man made electronic device today provides signaling that makes use of the great number of benefits offered by LED use.

Complications: LEDs have reached such high levels of popularity due to many factors including cost, power conservation, durability, low maintenance levels and long life cycle. Rarely are there failures for an LED application, once in use.  An LED lifecycle can be anywhere from 5-10 years so even replacement times are few and far between.

This does not mean that certain conditions such as hazardous and/or wet locations, low visibility or limited power availability can’t cause complications in design and implementation.

Solutions: For LED applications that are installed in hazardous or wet locations VCC offers a number of different solutions that can be put in place to protect your LED circuits. Implementing a specific LED type or using them in conjunction with a moisture sealed lite pipe will increase the durability and reliability of any LEDs being used outdoors where they are exposed to the weather or indoor locations where they are exposed to water and/or cleaning compounds.

The issue of visibility can also be addressed with a variety of products depending on the specific issue. VCC offers High Power LEDs for long distance viewing in addition to the expanded viewing angle of our products. We also offer a variety of colors, applications specific LEDs and even lite pipes that can increase the visibility in poor conditions and allow maximum viewing from all angles.

There are also a number of solutions that can be put in place to resolve power availability issues. If your head is swimming with all the possibilities and considerations for implementing your next LED application, contact VCC today. There is a team of experienced professionals available at the click of your mouse, ready to answer all your questions and help you select the LED series that will provide the greatest benefits to your project.

Emergency lighting and signaling is required in a large variety of enterprises including commercial, industrial, utilities, military, security, personal safety and more. One thing that is common to all emergency lighting and signaling applications is that extreme care must be taken when selecting the components used to make up the emergency circuitry.

Emergency lighting and signaling isn’t a case where damaged or defective lighting components are simply an irritation requiring maintenance, rather a time when an outage can mean shutdown of equipment for safety reasons or in the worse case, an injury or fatality. Today’s emergency lighting and signaling systems are increasingly being manufactured with LEDs to meet safety challenges such as:

• Reliability – LEDs are, by far, more reliable that other lighting options. When it is imperative that a lighting system function at a moments notice, using LEDs in your design will ensure consistent and reliable operation.
• Lower Power Consumption – LED circuits have lower power requirements than typical lighting options, thus resulting in a lower power requirement for your entire emergency lighting circuit.
• Improved Illumination – LEDs are brighter and can be seen from double or triple the distance of incandescent or fluorescent bulbs.
• No Filtering Circuit Requirements – Unlike standard luminaries, LEDs do not require a filtering circuit to remove the peaks of light outside the usable bandwidth.
• Durability – LEDs can withstand vibration, movement and rougher environments than lighting elements that have bulbs and filaments.
• Faster Switching – An emergency lighting circuit requires fast switching that is a characteristic of only one lighting type, LEDs. LEDs lighting circuit can be instantly switched on and/or off dependent on circuit requirements. There is no delay that can result in lost time in a circumstance where a second’s notice can prevent harm or damage.
• Extended Lifecycle – LEDs can have lifecycles anywhere from 5-10 years making them last many times longer than other luminaries.
• Simple Automation and System Integration – LED characteristics such as ‘Instant On/Off’, the low power requirements and pulsing allow them to be easily integrated into an existing circuit design or a newly automated system.
• No Mercury or UV Radiation – LED lighting options are not filled with mercury, neither do they emit radiation making them safer for any circuitry but especially circuits designed for safety. In addition, their safe composition means there are no special disposal requirements.
• Reduced Maintenance – LED usage as your lighting component will mean less downtime and therefore, less maintenance; this not only saves time but also increases safety and reduces costs.

VCC is ready and able to supply all your Emergency LED lighting and signaling needs. Contact us today and make your emergency lighting application more reliable, durable, earth friendly and flexible.

What are Light Guides and What Do They Do For Me?

A Light Guide is a device that allows light to travel from a source as large as the sun or as small as an LED, to a point at some predetermined distance. In a successful light guide application, this is accomplished with minimal losses.

What are the Most Efficient Light Guide applications?

The most efficient Light Guide applications are those that have a controllable source and use optical grade acrylics such as acrylic resin, polycarbonates, epoxies and glass. Controllable sources that are most often used in Light Guide applications are LEDs. Led and Light Guides create effective transmission of light from a PCB to a controller or dashboard as well as a number of additional applications. Efficient light guide systems will also provide the following design elements:

• Effective Coupling  – Without effective coupling from the source to the Light Guide, your system will be inefficient. Typical light guide applications will include a flux coupling to an LED device. The light guide entrance must be either flat (for surface mounted LEDs) or concave and contoured to match the mounting surface.
• Special lenses for Light guides can be manufactured to suit various types of LEDs.  Typically, surface mounted LEDs will have a built-in lens and the prepared end of the Light guide is inserted inside the mount to make the connection.
• Efficient Transmission – Efficient transmission is dependent on a variety of aspects including the Light Guide material, polished connection surfaces, and effective capture at the receiving end.
• Moisture Sealed – Many outdoor or hazardous applications will require moisture and dust sealant to provide an effective transfer of light through your chosen light guide.
• No conduction or transfer of electrostatic discharge (ESD) pulses – LED circuits, especially when mounted on a PCB, are susceptible to losses and damage from electrostatic discharge (ESD) pulses. An effective light guide removes this risk and also the need for an additional ESD protection circuit.
• Immunity to electromagnetic interference (EMI) – For light guides that are implemented into industrial environments, Electromagnetic Interference (EMI) exists, as there are various devices that are emitting electromagnetic waves. An effective Light guide will eliminate this interference.

VCC Optoelectronics provides an extensive variety of light guides called LitePipes, which are patented with the most efficient and technologically advanced design elements. Whether you have an indoor, outdoor, high interference or hazardous application, we have the right light guide for your project. Contact us today for more details and selection assistance from our qualified engineers.

Demonstrating VCCs capability for incorporating superior engineering aspects for some of the common limitations of mounting LEDs is the PCH 175 Right Angle Board Mount.  The entire product portfolio for circuit board mounts manufactured by VCC includes the circuit board standoff, the horizontal and vertical board mounts, and the right-angle board mounts.  The attempt at VCC is to overcome the threshold of barriers when mounting bi-lead as well as tri-lead PCBs.

The varied options of mounts and their greater flexibility allows for a greater choice of LEDs. The design of the circuit board becomes more compact as using the rectangular, round or the flangeless mounts ensures that the PCB mounts and the LED parts are that much smaller.

The PCH series is used for horizontal thru-hole mounting and the PCV series of mounts for the vertical through-hole mounting. Similarly, the SMD series of sockets allow horizontal surface mounting. The types of PCB mounting solutions presently available in the industry are limited. Mounting single or multiple array LEDs are increasingly difficult since soldering and overheating are common problems as is the assembling of multiple arrays. The only available solutions are fixed arrays that do not offer any design freedom.

The VCCs LED sockets deliver on all of the issues because single, dual, and triple mount sockets being technically superior, allow the LEDs to be placed in the sockets directly and do not require any soldering to keep them in place. Additionally single and multiple combinations with color selection of LED arrays are possible.

The VCC remains a better option as it is simple, hassle free mounting, assembling   in comparison to archaic techniques of soldering offered by competitors. The increase in the number of mounts facilitating better array formation as well as complete angle viewing greatly augment creative design of the display.

The engineering intent in LMS series Litepipes is to make them moisture resistant and dust-proof unit when display panels and the LED are attached to the circuit board. The design of the LMS Series allows it to be used seamlessly with both types of LEDs -surface mounts and the more common thru-hole LEDs. Hence, horizontal as well as vertical circuit board mounting is also effortless with the LMS series of Litepipes.

The device that makes the technology weatherproof, the gasket

The device that makes the pipe dust-proof and moisture proof is a simple yet marvelous piece of engineering a gasket. To render the circuit board free from dust and retain the non-penetration of dust particles and moisture, the lens of the Litepipe is fitted with a gasket.

The technology works once the panel assembly is done. The Litepipe unit, which is a tubular pipe with the lens and the gasket at one end, is inserted through the .281” panel pipe. A ring, RNG 268, retains it over the barrel of the Litepipe. The surface of the lens is then held taunt with a 5/16’’ deep socket against the panel. This compresses the gasket as the ring is pushed into position in the rear of the panel. This makes it easy to insert and remove the board easily from the panel.

Technical testing establishes the LMS lenses compliance to IP56/NEMA 4. These standards require ideal water and dust protection.  Moving beyond the requirements the unit also showed high standards of being 6 Gs shockproof and resistant to vibration (for 0 to 2000Hz vibrations). For storage temperatures of below 40 degrees to more than 85 degree Celsius and in solar, ice and UV environments the unit showed positive on all counts.

The LMS series Litepipes is to keep moisture/dust away and tough quality test assurance supported by positive reviews proves that there is better service and life. LMS series Litepipes are optimized for performance.

VCC panel lenses are made from polycarbonate of optical grade U.L.94V2 and are designed for superior output in comparison to industry comparables.  The VCC range remains attached firmly to the display panel even as the entire LED removal and insertion from the mount is possible.

In conventional LED lens mounts, the LED will simply protrude from the hole in the panel or is glued to the panel. This limits the viewing angle as well as increases the possibility of damage to the circuit board components because of increase in electro-static discharge.  The possibilities of a push-thorough happening also increase the risks of the lens falling down.

The availability of various configurations of the LED lenses from a mere 3mm to 10mm increases the scope of the final design of the display. Besides, the lenses only need to be inserted into the LEDs hole and the installation is complete. This therefore, increases the scalability as the LEDs mounted on PCBs as it is very easy to insert and remove a panel from its mount.

The factor that sets the VCC’s LED panel apart from the rest of the available products in this segment is the multiple choices in the lenses themselves. Round and square, low and  high profile, plain and Fresnel  types of lens with diffusion or threaded capabilities define the final illumination as well the viewing angle of the display. Adapting diffused light technology a new series of glow lenses are also available now. The panel lenses made from thermoplastic material allow uniform glow with almost full angle viewing capabilities.

VCC’s LED panel lenses are easy to insert in standard display panel, saving on logistics of installation and commissioning, besides being technically more sophisticated. Available in multiple configurations, VCC LEDs are the ultimate choice for ultimate illumination.

It’s about that time again; the 2011 NEC code is on it’s way and if you’re like 80% of the other Engineers, you are most likely too bogged down in your daily activities to have given it much thought. To reduce the panic that comes with the unexpected, we are presenting an overview of the changes scheduled for areas of signaling and indication. Information for additional changes, additions and deletions can be found on the NEC Site.

2011 Lighting, Communication and Signage Changes

• Article 404.2: A new subdivision will require grounded conductors to be provided to all switch location that control lighting. This will include occupancy sensors and other electronic lighting control devices.
• Article 410.130: A new requirement has been proposed that will require a disconnecting means to be added to existing florescent lights that do not already have a disconnecting means, when the ballast is replaced. This proposed change will result in the eventual protection of all florescent luminaries.
• Article 600.5 (B)(2): This new subdivision will limit the branch circuit size for LED type signs. No provisions existed previously to limit circuit sizes for new technologies. The proposed language for the change states that neon circuits can be a maximum of 30 amp and ‘all other signs’ will be limited to 20 amps.

2011 GFCI Requirement Changes

One of the largest areas of change is the requirements that are set for GFCI outlets that will protect and indicate proper operation of the device and associated circuitry. Many exceptions and areas of omission are removed and new requirements set in place. Below is a summary of the new GFCI required locations:

• Article 210.8 (A) and (B): A new requirement has been added to these sections that will call for all GFCI devices in Dwelling Units (A) and spaces Other than Dwelling Units (B), to be installed in ‘readily accessible’ locations. For example, you can no longer place them behind refrigerators, cabinetry or other objects that inhibit the ability to access the device for reset and testing.
• Article 210.8 (B)(7): All locker rooms with adjacent showering facilities will now be required to be equipped with 125-Volt, single phase, 15-20A, GFCI protected outlets.
• Article 210.8 (B)(8): Commercial Garages will now require GFCI devices in the garage, service bays and other spaces.
• Article 424.44 (G): This section implements GFCI requirements for heating cables that are installed in kitchens, bathrooms, Hydro massage tub locations and other similar facilities where water will be present through usage or cleaning of floors and equipment.
• Article 445.20: This article is new and adds a requirement for small portable generators, that are 15kW and smaller, to be protected with a GFCI device. The GFCI must be integral to either the portable generator or the outlet where it is connected.
• Article 517.2: A revision to this section increases the protection level of ‘critical care’ areas of hospital rooms. Previous code permitted a small portion of the room to be considered ‘critical care’ but the current revision requires the entire room to meet this level of care. As a result of this change, GFCI devices, among other provisions for health and safety, must be applied to all parts of the ‘critical care’ room.
• Article 547.5: This article was deleted as it contained an exception for GFCI devices to be eliminated in agricultural buildings if another GFCI protected outlet was within 900mm (3ft).
• Article 760.41 (B): Similar to the article above, this exception to GFCI installation is being deleted. Previously, NPFLA and PLFA fire alarm panels were not required to be fed from an AFCI or GFCI protected circuit. This was to avoid de-energizing the control panel without knowing and to avoid nuisance tripping. The committee decided that if other NFPA articles are met for installation and testing, a loss of power to the panel would be known quickly and addressed.

We hope this brief overview of the Signaling and Indication changes that are coming your way will be helpful in designing, planning and being prepared to implement the new changes. Contact VCC for assistance in applying your indication and signaling requirements.

*Reference:

NEC Site

International Association of Electrical Inspectors Site

Video gaming today isn’t about gathering a pocketful of quarters and heading down to the local strip-mall or neighborhood arcade. What was once state-of-the-art video based gaming such as motorcycle and car racing games, sniper shoot-outs and alien wars are now as old and obsolete as the word processor stored on the closet shelf collecting dust.

In today’s gaming world, dedicated gamers no longer need to leave the comfort of home to experience the best graphics and special effects that could once only be enjoyed in an arcade. The advances in video gaming have resulted in an extensive variety of compact controllers and systems that can be run from your own living room. The number of different consoles, the myriad of different games & the endless variations of what was once called a joystick and is now known as a “gaming controller” can leave one bewildered trying to decide which gaming platform to use.

The current ruler of the gaming universe is the XBox 360 gaming system. Not only are the graphics and video special effects superior but XBox 360 also allows the user to ‘go-live’ and play with other gamers around the world.

VCC has had the pleasure of working with a company called Viking360 that manufactures a USB programmable controller with downloadable updates for the XBox 360 gaming system. Their love of gaming led to the development of a ‘Rapid-fire’ chip that is used in the modified gaming controllers offered in their product line. You can improve your sniper skills, make one-shot drops, reload your weapon faster and essentially turn any one-shot gun into a rapid-fire machine gun that leaves the competition stunned. There are a plethora of mod-shops available but Viking 360 has the dedication, quality and love of gaming that has kept them at the forefront and led to innovative developments that are unavailable elsewhere.

Einar Offerdahl III is the owner and operator of Viking 360. After receiving his electrical engineering degree, he blended his knowledge and passion for gaming into developing new ways to improve the interface and controls of his favorite gaming system.  Recently, when faced with a NEW gaming controller design that will use 4 RGB LED’s per gaming module, he had concerns over cost, space and power consumption.

Einer’s research led him to choose the RGB LED’s made by VCC Optoelectronics, p/n VAOL-S19337RGB. As he told us, “This LED is much smaller than most of the LED’s I considered and seemed to lay down flatter when mounted on the PCB. After further review, the VCC LED’s were indeed lower power and less expensive than the others which made my choice to use VCC Optoelectronics RGB LED’s quite simple. Thanks to the support and service thru VCC and one of their Distributors, I will be using their parts in my latest design scheduled to go into production this quarter.”

VCC Optoelectronics has an LED to meet your needs also; whether it is compact design, low power consumption, superior brightness, cost or delivery, we are here to assist your selection and exceed your expectations. Contact VCC today to get your project started.

Click here for more information on Viking360.