W
Watson A.Name - \"Watt Su
Guest
I mounted 15 cheapo Hong Kong white LEDs on a protoboard last year and
ran it for awhile with about 25mA thru each LED. I didn't have it
running for months like I usually do, and it's been sitting around for
awhile.
I connected it up to a PS and with the current set at about 20mA,
several of the LEDs started flickering. First one, then a few more
started flickering at a few times a second, some completely on and off,
others just barely perceptible. Finally a few of the flickering LEDs
just quit completly, so I replaced a couple with some of the same
(unused) HK LEDs. The unused ones are much brighter than the rest, so
it's plainly evident that the LEDs deteriorated with whatevr use I gave
them last year.
I've run other white LEDs for long periods, and this is the first time
I've ever sen them flicker. Must be those cheapo Hong Kong LEDs.
Weird.
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
ran it for awhile with about 25mA thru each LED. I didn't have it
running for months like I usually do, and it's been sitting around for
awhile.
I connected it up to a PS and with the current set at about 20mA,
several of the LEDs started flickering. First one, then a few more
started flickering at a few times a second, some completely on and off,
others just barely perceptible. Finally a few of the flickering LEDs
just quit completly, so I replaced a couple with some of the same
(unused) HK LEDs. The unused ones are much brighter than the rest, so
it's plainly evident that the LEDs deteriorated with whatevr use I gave
them last year.
I've run other white LEDs for long periods, and this is the first time
I've ever sen them flicker. Must be those cheapo Hong Kong LEDs.
Weird.
--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@