\Skyray king mod idea.

Oh, and the current sense resistor looks like it is that R010 resistor in parallel with the R068 which is probably 8.7 milliohms for the pair, but could be 87 milliohms depending upon how the maker marks their resistors.

Welcome to the club, emkay!

Can I directly replace these with U2 without changing anything on the driver ?

Emkay, I would test the LED in question first by connecting 3.6v directly to the star contacts to make sure it is the LED and not just a broken wire or bad solder at the driver.

Emkay, if you do try johnnymacs suggestion, ( I would) just use a partially depleted 18650.

Exactly. Freshly charged 4.2v might damage the emitter. 3.6v should be fine.

JM, it really depends on the cell. IMR cells can easily kill them but the crappy trustfire cells will work just fine cause of voltage drop. Either way just run it in another light for a bit. :D

Ah, great idea to push the driver out through the switch hole... I finally got it out! Thanks, Serifus :)

Now I have plans... ^_^

DrJomes, you know more about chip programming than most of us.

Eagerly waiting for to your magic! :bigsmile:

There are 3 SOT-23-6 Buck drivers + external FET.

PIC/AVR send PWM signals though 10K resistors.

Good luck with the micro controller Dr Jones. Also it seems ive finaly found my self some time to do some sketching around in Eagle. if this all works out the way I hope it does, I’m probably only going to be getting more kings in the future.

the problem is connectivity between the circuit board and the led

If I apply power to the corner of the led it works

I would be tempted to get 3 xm-l u2’s on 16mm stars, ditch that one and keep the two functional ones for other projects…. 0:) J)

You should be able to resolder the connection or solder on a wire.

I saw on another post that with U2, initial output was higher, but then it decreased… maybe those U2 had flat PCB, copper PCB is the way to go in that case.

I’m going with 3 cheap U2 ones from dinodirect, just got to wait for them to arrive now…

I found this on google

That definitely looks like it could lead to something interesting.

Except as far as i can tell, it doesn’t match up to, what i assume is the PIC.

so the MCU isnt a known unit?

if someone drew out the actual circuit on a king, you could mount a attiny upside down on the board (pins sticking up) and use small external wires to solder to the correct pads on the board and then write custom controls for it fairly easily.

with those inductors on the board sticking up high, you have height for some creative wiring of a attiny in there.

Brian