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LEDS vs Diodes? Answered

I had a thought:
Since LEDs are a form of diode, can LEDs be used instead of diodes with similar properties in a circuit?

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Jack A Lopez
Jack A Lopez

Best Answer 10 years ago

Light emitting diodes are usually a poor choice for rectifier applications, for the reasons already mentioned: low forward current, low PIV, high forward voltage drop.

Conversely rectifier diodes are a always poor choice for light emitting applications since they don't emit visible light.

Occasionally LEDs are used for clamping small signals, as in the sound card protector circuit in the attached picture.

soundcard-protector.png
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framistan
framistan

10 years ago

LED's cannot withstand very much CURRENT amperage going through them in the forward direction. That is why they must have a current limiting resistor connected in series with it. Also, LED's cannot withstand very much BACKWARDS voltage... also called P.I.V rating (peak-inverse-voltage). So they will burn out if you connect them backwards... or if you connect them correctly with too much current. That makes them NOT GOOD for use as diodes, even though they technically are diodes.

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Re-design
Re-design

10 years ago

THey do have similar properties but leds are much more delicate than diodes and also drop more voltage in most instances so wouldn't be appropriate for an RF project probably.

ALSO, questions that have a title of less than 5 words get caught in a filter and have to be looked at by an real person instead of the robot.  Sometimes this may take several DAYS!

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steveastrouk
steveastrouk

Answer 10 years ago

+1 LEDS are also photosensitve, with a response peaking in the LEDs colour.