I had some cheap pink LEDs turn blue after a couple of months at nominal current On Wed, 15 Jul 2009 14:44:11 -0400, you wrote: >Hi Bob, > >I cannot help with white LEDs, but I can tell you that I did a test of >some blue LEDs (which are name brand, I think) and they ran for more >than 18000 hours at max rated current, room temp, with no noticeable >dimming. > >Sean > > >On Wed, Jul 15, 2009 at 11:50 AM, Bob Blick wrote: >> I recall some talk about short lifetime of some white LEDs but couldn't >> dig it out of the archive. >> >> Now that it's happened to me, suddenly I'm interested :) >> >> I've got some white T1 LEDs from here: >> >> http://www.led-center.com/led/new/white03.htm part number WL3-W15-2500. >> >> At rated maximum of 30 mA they seem to last about 1000 hours at room >> temperature. At 20 mA they last a little longer. >> >> Then they get dim, about 5% of the new brightness. The color stays about >> the same. So I assume the phosphor is OK, it's the blue LED that has >> weakened. >> >> I've never seen this happen with blue LEDs. Maybe the white phosphor >> pollutes the LED? >> >> I haven't had this problem with "name brand" white LEDs. >> >> Anyone see this happen before? >> >> Cheerful regards, >> >> Bob >> >> -- >> http://www.fastmail.fm - The way an email service should be >> >> -- >> http://www.piclist.com PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist >> -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist