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Light Emitting Diode: Difference between revisions

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[[Category:Secondary]]
[[Category:Secondary]]
[[Category:Electronics and Control]]
[[Category:Electronics Components]]
[[Category:Materials and Components]]

Revision as of 08:18, 3 June 2015

LEDschematic.jpg

Light Emitting Diodes (LED) come in different colours, shapes, sizes and brightness. The more common colours being red, green and yellow.


They are also available in bi-colour and tri-colour versions. Round ones come in 3, 5 and 8mm sizes. There are also rectangular, square and bar types.


Flashing types are available and seven segment displays are made of a number of LEDs in a particular pattern.


LEDs are easily damaged by excess current therefore it is normal to connect the LED to the supply via a series current limiting resistor. The value of this resistor is not critical but is usually within the range 100 - 330R.


Polarity must be observed when connecting LEDs (it should be noted that LEDs are damaged by reverse biased voltages larger than about 6 volts).


The Anode is connected to the positive supply via the limiting resistor. The Cathode is connected to the negative supply.