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Making a poster with 5mm 2 pin LED lights.

  1. Nov 13, 2012 #1
    Hey, I want to make a get better poster with led light sticking out of the poster. I found the following LEDs: http://www.play-zone.ch/de/bauteile/led/led-sortiment-mit-180-leds-oem.html [Broken]. I have very little experience with wiring circuits (did AP physics a while back) and I'm not sure if this is even viable? I want to have around 10-20 LEDS consisting of 3 different colors powered by a battery(s). Can a simple button battery power a couple of LEDs for a reasonable amount of time? Should I buy a different voltage battery for each of the 3 colors? If this is even possible how should I go about this project?

    Thanks so much in advance for helping a noob out :)!
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Nov 13, 2012 #2


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    Staff: Mentor

    They need ~20mA each ("Verbrauch" row), with less they will lose a bit of their brightness. 10-20 of them need ~300mA at ~3V, giving a power of ~1W.
    If you have a battery with 300mAh, for example, you can power the LEDs for approximately 300mAh/(300mA)=1hour. The button cells don't have the required voltage, so you probably need 2-3 of them in a row. This does not change the calculated lifetime. In addition, don't forget to add a resistor to limit current flow, otherwise you could ruin your LEDs or the battery (or both).
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