In the late 1920s, the Russian semiconductor physicists invented the LEDs (Light Emitting Diodes) without knowing its infiltration in many technologies after 100 years. After many ‘trial and error’s in adding impurities the LED for the next 20 years by different people finally the light emitting phenomenon was identified. At that time, the invisible infrared light emission was developed for controlling non communication systems with modulating its forward current. 20 years later, the Texas instruments commercialized the LED to the public. The first visible light from LED emerged in 1962 with the red color spectrum from General Electric. The spectrum in yellow and orange color impurities were added from the research done in the next 5 years and was suited for the markets. In 1976, the term ‘high efficiency of LED’ under analysis of performance improvement for communication to adapt wavelengths. 

The LED specifications brief in the datasheet including packaging details, part number, electrical characteristics, and optical characteristics. The electrical characteristic small voltage is prime factor which is accountable for initial current flow through this component. Like all electronics components the current flow rises very restricted by small amount of LED core resistance.  This property reflects as the characteristics of any basic diodes. In real time, this practice is not regular as imposed the battery or any other sources may ruin your LED. We need to perform this course of any system where the LED come into embodiment.

The simple method of driving LED in effective manner is introducing the extra resistor between source and LEDs. The concept of Ohm’s Law and Voltage division rule applied for deciding the value of series resistor from the linear characteristics of voltage and current. But the voltage – current characteristics of diode is nonlinear which is match with resistor linear characteristics. The large number of linear variations in the resistor due to battery voltage variations dominate the nature of LED results in limiting the current.  The selection of resistance balancing between the resistor and LED with ratio of 1:3 for effective driving the LEDs. Many methods including driving from constant current source and switching mode integrated circuits performing same operation with the same resistance ratio without the any heat dissipation.

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