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identifying LEDs (lesson 3)
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identifying LEDs (lesson 3)

by ih8gates on Sun Feb 03, 2008 10:45 am

A question about ID-ing LEDs. Lesson 3 points out that the anode (+) lead will be longer on LEDs. It also mentions that there's a bit more metal on the cathode (-) inside the LED.

It seems that the latter isn't always correct - the red diffused LEDs that are in my starter pack all have their bigger "lump" on the + side (connected to the long lead).

Everything appears to be working as expected for me... so I'm guessing that the 'big part is on the (-) side' is not a hard-and-fast rule. Seems to be the case *usually*, but not always.

So... if you have occasion to trim the leads on LEDs, keep the anode long so that you can ID it correctly later.

Or... do I have some malformed franken-LEDs?
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by magician13134 on Sun Feb 03, 2008 12:49 pm

In all the LEDs I have ever gotten up till this kit, the anode flag has been the smaller one. The ones that came with this kit had a smaller flag on the cathode side. I wouldn't use that as a judge, use lead length or flattened side.
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Please be positive and constructive with your questions and comments.