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How to make LED work on AC source

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mohitdaksh

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My question may be rather silly. But I want to ask do normal LEDs work on ac supply.. I am trying to get one working on 5V 50 HZ.. But it is not working.. Any ideas?
 

LED on AC source

Yea, surly works!
You need exactly so the serial resistor as fro DC supplying(&revers polarity protection): AC Line powered LEDs, www.qsl.net/yo5ofh/hobby circuits/led_circuits.htm
K.
 

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    mohitdaksh

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Re: LED on AC source

Thanks a lot for the replies..



Why the zener diode?? Why won't the circuit just illuminate at a lower intensity or toggle states with just the resister?
 

LED on AC source

The LED most be protected from high reverse voltage, that would destroy it. For a better current utilization, you may want to use a bridge rectifier.
 

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    mohitdaksh

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LED on AC source

It doesn't need to be a zener - any diode will do (or another LED).

Very wasteful of power though!

Keith
 

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    mohitdaksh

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Re: LED on AC source

Anther factor against using an led for ac supplies is that the eye can detect the 50 hz flicker from the diode, not if you look directly into it but at an angle momenteraly , very off putting.
 

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    mohitdaksh

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LED on AC source

There are chips around to do the job properly, eg

Keith.
 

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    mohitdaksh

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