Multiple LED's

[Roctopus]

I'm working on an idea that would require me to have three external LED's. However most builds only have one LED. Is there a way to wire more than one LED to a build? If so, how would you do it?

Thanks!

[gtr2]

Can you clarify how you plan to run the leds.  In series on one switch?

[Roctopus]

Can you clarify how you plan to run the leds.  In series on one switch?

Yes. I want to put them in clear shaft pots and illuminate three clear knobs at the same time.

[k.rock!]

I would think running them in parallel might be best... like this:

           ----|>|----
          |              |
+9V---- ---|>|---- -------ground
          |              |
           ----|>|----


This will supply even voltages to all three of them


-Kaleb

[oldhousescott]

Sorry Kaleb, but no. Whichever LED has the lowest forward voltage drop (even with LEDs of the same type) will get all the current. Put them in series, nose-to-tail. Figure a total voltage drop of about 6v for the three LEDs and calculate your dropping resistor from that.

You could put individual dropping resistors for each LED, but that would mean two more parts and extra wasted energy in the form of heat from the resistors.

[k.rock!]

Sorry Kaleb, but no. Whichever LED has the lowest forward voltage drop (even with LEDs of the same type) will get all the current. Put them in series, nose-to-tail. Figure a total voltage drop of about 6v for the three LEDs and calculate your dropping resistor from that.

You could put individual dropping resistors for each LED, but that would mean two more parts and extra wasted energy in the form of heat from the resistors.

Ah! Thanks for clearing it up!  :-[Sorry about that Rocktopus haha

It's always cool to have people like you around to teach us new things Thanks oldhousescott!


-Kaleb

[gtr2]

Sorry Kaleb, but no. Whichever LED has the lowest forward voltage drop (even with LEDs of the same type) will get all the current. Put them in series, nose-to-tail. Figure a total voltage drop of about 6v for the three LEDs and calculate your dropping resistor from that.

You could put individual dropping resistors for each LED, but that would mean two more parts and extra wasted energy in the form of heat from the resistors.

Yup, I found this out the hard way once...   

[bigmufffuzzwizz]

Great example of this taken to an extreme!!! 
http://www.madbeanpedals.com/forum/index.php?topic=1512.0

I was surprised the first time I realized its as easy as connecting them in series..

[JeffdaMaori]

... may I add that those are indeed all connected in parrallel though... sorry to spread confusion....

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[JeffdaMaori]

... and science says that bumble bees can't fly by all principles of aerodynamics I was told...

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