Question: What gets fried when you over voltage feed an LED?

LED Flashlights – General Info
1

topic says it, what gets fried in the circuitry of a flashlight? Driver, LED or both.

I wish to know so I know what I need to replace. If I see something that is broken, can be fixed and I am capable if fixing it, I will usually do it.

Got my a soldering iron now! Finally, I've used them in school before and my skills are supposedly best in my class at the time.

EDIT: In case this needs more clarification, I mean if you use 2 batteries instead of 1. eg. 2 16340s instead of 1 18650 on a 4.2v max driver/led.

2

Driver usually goes.

3

Unless its direct drive then you can burn the LED.

4

So the LED is fine and all I need to do is replace the driver?

Thank you for your responses.

5

Almost certainly. You can test the LED by connecting wires to a battery and touching the solder pads. Shield your eyes.

6

If you do that use an almost discharged battery. Full 4.2V can be bad on a 1A rated led even for a few sec...

7

Sometimes the LED will turn brown when it is overdriven, and there is no recovery from that. If the LED is still yellow, it is probably just the driver.

8

You can sniff the driver and LED separately. Not foolproof, but if you smell burnt electronics on the driver board, that's a darned good indicator that you need a new driver.

9

I have had a couple mishaps and will say it's pretty hard to cook the emitter and fairly easy to cook the driver.

10

Well Erik, I guess now would be the time to admit that I fried my brand new SST-50. It is 4.2 volts max and I fed it 6 volts.

Don't ask.

It still comes on but is dimmer than an XP-E now. Does the emitter get lighter or darker if it's blown?

sixvoltFoy

11

Still sounds like the driver is shot. Some blown drivers bypass and go into DD and others simply don’t pass enough power and light the LED dimly. Do the direct to LED pads battery test and see if it runs bright or not.

12

Hey it happens, I have cooked a couple this is how we learn be thankful these are budget lights and not mega expensive. Burnt emitters usually don't light at all. Pack it up and mail it to me and I will fix it for you.