I replaced #194/T10 incandescent lamps in my car with LEDs. But the LED's last only about 1 year and then start blinking, strobing and cutting out. I've seen this before as a bad connection - bonding wire or die-attach adhesive failure.
Here (pics) I see some strange black regions first around the die then spreading out on the lead frame - so I think this is the problem but not sure what it is. These are in a sealed light fixture with no corrosion anywhere.
Normally there are five SMD5050 LED's that each have three dies inside, in series. The five LED's are in parallel with a 62 ohm resistor feeding it. I removed two LED's (so total of three, for a bit brighter) and measure total 75mA at 14V, giving 25mA per LED die, they don''t run hot.
Just wondering what is this black plague on (Chinese) LEDs, it seems to give them a short lifetime.
Here (pics) I see some strange black regions first around the die then spreading out on the lead frame - so I think this is the problem but not sure what it is. These are in a sealed light fixture with no corrosion anywhere.
Normally there are five SMD5050 LED's that each have three dies inside, in series. The five LED's are in parallel with a 62 ohm resistor feeding it. I removed two LED's (so total of three, for a bit brighter) and measure total 75mA at 14V, giving 25mA per LED die, they don''t run hot.
Just wondering what is this black plague on (Chinese) LEDs, it seems to give them a short lifetime.
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