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Newbie with a specific LED flash/flickering question.

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Clydesdale

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I'm pretty new to doing my own electronics and still learning, but wanting to put my so far limited knowledge to work I decided on a little project.

I have this little phaux LED votive candle I'm curious about. It's a little yellow LED that flickers like a flame and looks pretty realistic. Knowing it had to be pretty simple I opened it up (Busting it in the process) and it is ridiculously simple.

However, there is something buried under this black daub of epoxy...I have no idea if there is a way to get this off to see whats under it...was going to put a hot air tip to it and see if it will melt but that wont be here until Monday..

Anyone have any idea what this could be? I'm going to hazard a guess at some SMD or tiny IC. See picture. It's about the size of an old 50cent coin.

Clyde
 

Clydesdale

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Looks like I answered my own question..only to pose another one. I was able to use an soldering iron to remove the black blob of whatever...but there did not seem to be anything under it..until I started to examine the bits and powder that made up the black blob. Well, I found thing teeny tiny little bugger. The attached pick is from a poor mans USB microscope, magnified about 70x. Tiny SMD of some sort?
 

betwixt

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Clydesdale. I think you killed it !

It's a small IC, probably a random sequence generator to make the LED flicker in an unpredictable way. The IC would have been glued to the board, had wires bonded from it to pads nearby then had the blob of epoxy dropped on it to protect it.

If you want to resurrect it you will have to make a similar function using a conventional IC, something like a PIC10F200 comes to mind.

Brian.
 

Clydesdale

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Definitely killed it! I figured it was something along those lines. I found a plan for something like it that uses a Attiny13 that I'm going to give a go.

Thanks for the reply!

C.D.
 

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