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Re-using LED bulbs.

DrG

Active Member
I have a set of lights with LED bulbs like this one.
Bulb 20200125_141134_HDR.jpg
One of them starting blinking intermittently. It was annoying. I switched bulbs between two sockets and the same one continued blinking.

I replaced it and there is no more blinking. But I wondered if there was anything in the bulb that might interest me. So, I took the top off.
leds 1 20200125_141610_HDR.jpg

There they are - 10 LEDs.

Then I took the bottom off and removed the high voltage guts (there are some smt chips on the back). There is nothink I want from that board - why scavenge a few cheap parts from something that was defective?
guts 20200125_201627_HDR.jpg

The LEDs interested me. Here is a close up of that board and it is metal (with a lot of heat sink compound on the other side).
LEDs 2 20200125_162024_HDR.jpg
I think you can see that the LEDs are in a serial configuration. I estimated a 3.6V drop and I really have no use for a set at that high of a voltage to use all ten in the circuit.

LEDs F 20200125_210641_HDR.jpg
I scratched through the painted surface to make some "pads" and checked each LED and they all lit. I suppose I could make use of some/all of them in a parallel fashion. It has been placed in the junk box.

One piece that I saved and probably will use is the surface of the bulb.
diffuser 20200125_204256_HDR.jpg

It may be a decent light diffuser for some photography uses.

That's it, that's all I got...but no more annoying blinking.
 
Last edited:

Les Jones

Well-Known Member
Most Helpful Member
I think the electronics part could still be working and the blinking caused by a faulty LED. I have had a similar problem with a unit I built using seven 1 watt LEDs in series fed with a boost converter modified to give a constant current. I think that the LED warms up and thermal expansion breaks a connection inside the LED. The LED cools down again and the connection is remade and so the cycle continues.

Les.
 

Diver300

Well-Known Member
I have also had LED lamps blink when the capacitors have degraded.

The ones that have a bridge rectifier directly on the input can be run with an external rectifier and smoothing capacitor. That avoids the need to open them up.
 

dr pepper

Well-Known Member
Most Helpful Member
I've had this and I think it was one of the bond wires inside the led failing, shorting out that led made the lamp work again.
A while back when this style of lamp was just becoming popular I reconfigured one to run off 12v when I needed one, it still works, I dumped the driver board & replace dit with a simple resistor.
 

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