Just finished testing more LEDs in the 30ma 192 hour test. After the practical failure of another WW LED in this test earlier, I wanted to try some other ones. I'd like to use WW more.
The Left column is the tested ones, the Right column is the control group.
First row. superbrightleds.com 5mm WW 7cd 35 degree. It dimmed only slightly, but failed in another way. It now conducts in reverse bias a few ma and does not light in forward bias until over 5ma is applied. Seems to have a conducting channel form in the die like ESD damage causes. Failed the test.
Second row. 3mm WW from GE Xmas light string purchased in 2007. It faded, but not to severely. It should last long in 10-15ma applications.
Third row. 3mm WW from GE Xmas light string purchased in 2008. They changed the LED from the previous year. Newer is not always better. It seems brighter, but that is light concentrated in the narrower beam. They have some color inconsistencies as well. It faded quite a bit. Failed the test.
This is a good example of how a manufacture may replace a better performing product with a poorer one to generate better margins. Unfortunately, this ONLY sours the product for the consumer and makes LED products gimmicky. Just check the "Lights of America" thread over in the fixed lighting section!
Now, I have the Jeleds, Light of Victory (55cd) and the Radio Shack 276-0017 White LEDs in the cooker. Hope to report on the LOV WW flux too.
I'll have to order some JELED Warm and cool white flux LEDs to see how good they are.
http://home.worldnet.att.net/~jriegle/ww5mm.jpg
The Left column is the tested ones, the Right column is the control group.
First row. superbrightleds.com 5mm WW 7cd 35 degree. It dimmed only slightly, but failed in another way. It now conducts in reverse bias a few ma and does not light in forward bias until over 5ma is applied. Seems to have a conducting channel form in the die like ESD damage causes. Failed the test.
Second row. 3mm WW from GE Xmas light string purchased in 2007. It faded, but not to severely. It should last long in 10-15ma applications.
Third row. 3mm WW from GE Xmas light string purchased in 2008. They changed the LED from the previous year. Newer is not always better. It seems brighter, but that is light concentrated in the narrower beam. They have some color inconsistencies as well. It faded quite a bit. Failed the test.
This is a good example of how a manufacture may replace a better performing product with a poorer one to generate better margins. Unfortunately, this ONLY sours the product for the consumer and makes LED products gimmicky. Just check the "Lights of America" thread over in the fixed lighting section!
Now, I have the Jeleds, Light of Victory (55cd) and the Radio Shack 276-0017 White LEDs in the cooker. Hope to report on the LOV WW flux too.
I'll have to order some JELED Warm and cool white flux LEDs to see how good they are.
http://home.worldnet.att.net/~jriegle/ww5mm.jpg
