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Light Emitting Diodes Technology

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With so many design options, the imagination becomes the primary limiting factor in many custom LED lighting designs. Customers normally already have an established set of basic design parameters during the earliest stages of product development. As they begin to explore additional opportunities, they begin to realize the full potential of a custom LED lighting product. The technological articles listed below can provide a customer with many new ideas. However, our high power LED driver design capabilities are never limited to these basic descriptions. The following content will not only stimulate your imagination, but also provide a basic educational outline to several of our LED design capabilities.

light emitting diodes

Custom High Power LED Driver

High power LED drivers are available in various packages ranging from integrated circuits to external enclosures. High power LED driver circuits incorporate buck or boost driver topology. The buck high power LED driver applies to circuits with an input or rail voltage higher than that required across the light emitting diodes junction or junctions. This is ideal for low voltage AC to DC applications. Many LED drivers allow the engineer to program the drive current by selecting an external resistor value. Some of the most recent devices only require as little as one external component for operation. The boost converter high power LED driver applies to circuitry with a source voltage lower than that required across the LED junction or junctions. This driver topology is ideal for many battery-operated devices. Consider a lighting application powered by two double A batteries. The total source voltage is approximately 3 volts, but the light emitting diodes requires at least 3.5 volts across the junction. In this case, a boost converter can provide the proper operating voltage allowing the light emitting diodes to operate. LED truck lights normally rely on a 12 volt power supply, and do not require boost converters.

High Power LED Controller

It is very common for a light emitting diode application to operate in unison with other circuitry, external devices, or humans by mean of a high power LED controller. Some lighting applications require external sensory arrays, such as light or sound sensors. Other lighting applications may interface with circuits on automobiles, motorcycles, or LED truck lights, to provide the high power LED driver circuitry with logical inputs from these external systems. Almost all LED controller circuits require some type of human interface, allowing the logic components to accept input signals from humans. Several examples of human interface devices include the keyboard and mouse on your computer. A light emitting diode related example might include an LED light mounted within the kitchen to illuminate the main work area. A single push button located on the LED light bar provides functionally for power as well as dimming. Each time the user depresses the push button, the light emitting diodes will increase their brightness. After five subsequent depressions, the light emitting diodes and high power LED driver turn off.

High Power LED Lights

The high power LED offers a new advancement to the LED lighting industry and can produce more lumens per dollar than traditional emitters. Predecessors included the 5mm though-hole light emitting diodes, which provided approximately two to three lumens and dissipated about 100 mW. Shortly after came a four-leaded through-hole package often referred to as the Super Flux, commonly found in LED truck lights. This package offered a total luminous output of about four to five lumens, while utilizing all four leads to aid in heat transfer away from the die. Eventually light emitting diodes became available in a surface mount package, which allowed direct mounting to pads located on the circuit board. SMT or surface mount technology further improved the thermal efficiently of the light emitting diode by allowing heat to transfer directly into the circuit board without passing through a small wire lead. To add even greater efficiency, manufactures integrated a heat slug directly into the bottom of the surface mount package. Since the slug is located directly beneath the LED die, heat can now efficiently transfer from the light emitting diode junction out of the case, and directly into the circuit board on which the LED light is mounted. Today, the high power LED relies on the central heat slug to dissipate heat from the die. Older designs including many LED truck lights still rely directly on both anode and cathode pads for heat transfer.

Specialized LED Circuitry

Unlike LED truck lights, some LED lighting applications require more than a single colored LED light. A retail display designed to draw the customers' attention might produce up to thousands of unique and beautiful color variations. It would be impracticable and nearly impossible to provide a separate LED lamp for each distinct color, especially when considering that standard LED lamps are commonly available in only twelve standard colors. Color mixing provides the most feasible and cost efficient solution for lighting applications yielding an array of colors. Color mixing technology is very simple, and relies on high power LED driver circuits to combine a set of primary colors and produce other distinct colors. As a result, an elementary LED circuit can effectively produce a nearly unlimited number of new color combinations. Many modern LED lighting applications employ color mixing technology. Several examples may include signage, retail displays, full color displays, architectural and ornamental light emitting diode applications.

LED Circuit Board Design

LED product manufactures always intend to produce a product to best accommodate the consumers needs. To accomplish this, they may design the LED product according to common utilized dimensions, potentially allowing many consumers to adapt the product. This may be acceptable in many low-end lighting applications. However, most product designers like to be as precise as possible when considering the design for a new lighting product, such as LED truck lights or other lighting applications. Scalable architecture provides increased flexibility for the LED product designer by providing a series of interconnecting light emitting diodes and high power LED driver circuits. If an application requires a slightly larger dimension, the addition of an extra LED module can accommodate empty space without completely revising the entire design. Not only can this save time and money, but it also provides much greater flexibility for future product revisions. As lighting technology progresses, LED lamps will become increasingly efficient. Many lighting applications will need to increase their overall luminous output in order to compete with the competition. By incorporating scalable architecture into a design, it is easy to add additional light emitting diodes or LED modules as applications require an increased luminous output.