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LED 1 Voltage

SnoozrSnoozr
edited October 2013 in Troubleshooting
Had a great build except for LED 1 does not work.  It doesn't appear to be an orientation issue.  I did compare the voltage versus LED 2 and adjacent, and it seems like the voltage is two to three times higher. The voltage arrives in time with the sequencer when you press play, so the voltage is being sent at the right time but it seems high.  I checked the data sheet at Mouser and as far as I can tell the LED 1 is supposed to take up to 2V.  The voltage measured is below this.  Does anyone have any ideas?  Maybe the LED is DOA? 

Also it appears Mouser and Digikey are out of stock so if any one knows of an alternate supplier that would be great.

Comments

  • aerroraerror
    i don't know what voltage should arrive at led1 but if the led is doa, reichelt have them in stock
  • lovelygroovelovelygroove
    Hello, I had the same problem with 2 LED ... they are very fragile and do not support heat if heated too long ... I made a paypal payment Julian and I received them in less than a week!
  • fcd72fcd72
    Maybe you just swapped a Resistor.....
  • SnoozrSnoozr
    edited November 2013
    I went and checked some more things.  I pressed the trigger buttons 1 and 2 so both LEDs would receive power.  LED 1 is receiving 5v while LED 2 is receiving 2v.  So hoho, there's the problem it would seem.  I checked RR2 which LED 1 is connected to and all pins are 221 ohms between them and ground.  I verified that the orientation of RR2 is correct so that the ground pin was in the proper place.  The source of the power appears to be U7 but I don't know why it would give 5v for one LED and 2v for the remainder. Hmm, any ideas?
  • SnoozrSnoozr
    More work on this.  I checked the area for shorts and did not find any. 
  • tixivtixiv
    Measuring 5V is normal if the LED is open circuit (or reversed). It is because in that case the LED's resistor doesn't drop any Voltage.
  • SnoozrSnoozr
    ^ Ah, good to know.  It must be the LED then.  I poked around on Reichelt but it appears the original link above was for a green LED (picture is orange but text says green) whereas this link gives the orange one.
    http://www.reichelt.de/LEDs-Special-Shape/V-321/3/index.html?&ACTION=3&LA=446&ARTICLE=22209&GROUPID=3023&artnr=V+321

    But they want a 10 euro minimum order to ship to the US so I guess that is a deal breaker.  Maybe Julian has extras he is willing to sell?
  • nightworxxnightworxx
    You should better ask him ;-)
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