On Monday, February 20, 2012 08:55:13 PM Stephen Dubovsky did opine: > Gene, > The datasheet says logic high when the slot is clear, logic low when > interrupted. So sounds like you have no LED. FWIW, 0.8V seems REALLY > low for a LED. Typ about 2x that. Esp running @ 25mA. The max > reverse led voltage is listed as only 3V. Was it ever hooked up > backwards? Could have caused the LED to become a DED (Dark Emitting > Diode). ESD can kill them too. Either try another one or shine an IR > LED at the receiver side (from a TV remote??) and see if the detector > side is good. > > Stephen > Assuming its hooked backwards, how much normal one diode drop current going the wrong way does it take to kill a typical LED? I was thinking about making a couple razor cuts, and doing a crossover with wire wrapping wire to see if it was salvageable. If that worked, then I'll reverse it and make Y.A.Board that is wired right. And if they are trashed, I still have about a 12 pack left. :)
I have tested regular leds to see which way was right without blowing them before, so ISTM that as long as it was current limited, I probably should have gotten away with it. I'll go try the reverse in place idea for one of the 3 on that board and see I guess. Thanks & Later, after I've cobbled up the reversal. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> Neglect of duty does not cease, by repetition, to be neglect of duty. -- Napoleon ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
