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Check out this simple kit offered by Eric Thompson’s Low Voltage Labs:

This year at the Seattle and Portland Mini Maker Faires I did a presentation on getting started with designing your own PCB using KiCAD. In this presentation as an example I created a pumpkin shaped PCB with a candle-like flickering LED. I’m releasing the KiCAD schematic and PCB layout files to use as the starting point for your own project.

You can also buy the kit from Eric’s store. Great for putting into punkins in place of a candle!

John Baichtal

John Baichtal

My interests include writing, electronics, RPGs, scifi, hackers & hackerspaces, 3D printing, building sets & toys. @johnbaichtal nerdage.net


  • http://www.fuckinstagram.com Luke

    Can someone please explain to me how this circuit causes the LED to flicker? I am new to electronics and can’t figure it out purely from looking at the schematics. Is it a special kind of LED?

    • http://gravatar.com/alexhgian Denwa

      I’m not sure how it works, but its probably built into the led. I’ve seen leds that can strobe or flash by themselves. Like this one i found on adafruit: https://www.adafruit.com/products/680

    • http://gravatar.com/mupeg Sean

      Luke, I had the exact same question when I saw this at the Portland Mini-Maker faire. I though I was crazy (or at least lacking some serious knowledge). It is a special LED with a flicker circuit built in.

    • http://gravatar.com/toupsz Zach

      Yes, it’s a flickering LED. From the BoM –> data sheet.

      http://www.betlux.com/product/LED_lamp/Blinking%20LED/BL-L513-B.PDF
      -Z

    • http://jammitweb.blogspot.com/ jammit

      It’s definitely an LED with an integral chip, designed to make the LED flicker. You can buy LED’s that have a built in blink chip, built in resistance or current regulator, color changer, or whatever. You can even special order LED’s with chips built in that are programmed at the factory to blink in any way you want (be prepared to order them in lots of 10,000).

    • http://jammitweb.blogspot.com/ jammit

      Forgot to add:
      Evil Mad Scientist has flickering LED:
      http://evilmadscience.com/productsmenu/partsmenu/353

    • miroslava von schlochbaum

      it’s an interesting question from a design standpoint. can anyone assert/guess what that LED/chip is doing? that is, does the flicker repeat after a sequence or is there some sort of thermal resistor noise going on?

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