NJG-18, multimode boost driver for 445nm.. and possibly 650nm

Re: NJG-18, 3 mode driver for 445nm with single cell

True, but if you have a driver with no inductor, then you know for a fact that it isn't a boost driver, so what I said originally is still true.

Re: NJG-18, 3 mode driver for 445nm with single cell

Merry christmas and Season's Greetings!!

qumefox:beer: and Pontiacg5.:beer:

SHIN

Re: NJG-18, 3 mode driver for 445nm with single cell

SHIN said:

Hi. DTR.

That's 8x amc7135 board. (8x 350mA=2.8A)
But it's not boost driver for single cell 445nm, too.

I appreciate your idea for 5-pin chip heatsink. Thank you.:yh:

SHIN

Click to expand...

That is alright I may make a flashlight or run 10 LOC diodes in parallel with the thing. Electronics are definitely not my strong suite but I have learned a lot.

I did order one of the NJG-18's to test as well.

Thanks. I is neat to think that in the process of learning this hobby I have been able to come up with a couple game changers.:beer:

Re: NJG-18, 3 mode driver for 445nm with single cell

I always surprise at your skillful "masterpiece".
Thank you for sharing infos.

There are some mode-group differences in NJG-18 because IC programming is slightly different between the batches. (from CPF)
I wish your NJG-18's are those you want.

Merry Christmas! DTR.:beer::beer:

SHIN

Re: NJG-18, 3 mode driver for 445nm with single cell

I've got one of these on hand, I quickly connected it on 1W white led and o-scope, added 220uF and 100n capacitors in paralell to output wires and this is what I got

what about these spikes?

Re: NJG-18, 3 mode driver for 445nm with single cell

Those spikes are actually fairly minimal compared to some of the LED drivers i've put on the scope. A 445 should handle them without much issue since they're fairly robust, especially if a good filter is used on the output of the driver.

Re: NJG-18, 3 mode driver for 445nm with single cell

so it IS safe for 445nm...
if yes, then BUILDING TIME :san: (but I'll probably keep those capacitors)

Re: NJG-18, 3 mode driver for 445nm with single cell

Well SHIN has a working build using this driver, so that alone is proof that it's not instant death for the LD.

I plan to order some for myself to play with as well when I get around to ordering the next batch of laser build stuff.

Re: NJG-18, 3 mode driver for 445nm with single cell

well I think there's some problem with the pot - when I'm turning it clockwise (on full mode), the current grows from 190mA and when the pot is turned into middle position, current reaches like 450mA and when I continue turning, the current starts TO DECREASE! :wtf:
so what now? :undecided:

Re: NJG-18, 3 mode driver for 445nm with single cell

Thank you for the explanation. qumefox.
My specialty is way from the electronics. Sorry. 3zuli.

My 2 of 445nm were connected to NJG-18 with no additional capacitor except heasink for 5-pin chip.
After 1st build was finished with some courage, I tuned on that with praying.
The 2nd build was very easy. No need of courage nor hesitation.
So I set the pot after the building, with LPM.
Both are still working good.

My NJG-18's were from KD. 3-mode both.
There is mode-variation in NJG-18 because PWM IC programming is slightly different between the batches according to the time of their production. (heard from CPF)
And one can remove "the modes" then single mode as posted previously.

Mismatch of power-current of the low mode is also due to PWM.

The current is increasing as turning the pot counter-clockwise in mine.

Good luck! 3zuli.

SHIN

edit) My pot was set at 135 degree counter-clockwise from factory-setting.
At that position, the pot was somewhat sensitive.

And one more thing, because this driver has "modes", you should test the current "several" times as when you use multimode-flashlight.

I wish your driver has only 3-modes.

Re: NJG-18, 3 mode driver for 445nm with single cell

Moved to next page.

Re: NJG-18, 3 mode driver for 445nm with single cell

Nice build, but just a quick question about the heatsinking- why is the inductor heatsinked, but the semiconductors not?

In the driver, the semiconductors are responsible for the majority of the heat generated. The coil shouldn't be getting hot enough to require heatsinking at all.

Re: NJG-18, 3 mode driver for 445nm with single cell

goninanbl00d said:

Nice build, but just a quick question about the heatsinking- why is the inductor heatsinked, but the semiconductors not?

In the driver, the semiconductors are responsible for the majority of the heat generated. The coil shouldn't be getting hot enough to require heatsinking at all.

Click to expand...

It is the only thing I could easily sink. The driver was not getting hot on my supply so it is mostly making a good place to mount it.


Also on my next one I am thinking about lengthening the spring and letting it make contact with the plate in the host so that I would not have to solder the positive wire. It would be like a drop in module and all that has to be done is screw the head on.





Here it is again. Moved it from the previous page.












This is the first unit that I have had with strobe mode and have to say it is pretty neat. Also the Hotlight host I used worked well with the side clicky being that I can do a momentary style push on the clicky with it in the on position and change the modes without have to do a full on off cycle.

Here is a little video I did.

Re: NJG-18, 3 mode driver for 445nm with single cell

Nice build!! DTR. :gj:

My driver is arrived from DX. There is a premade hole at LD(-) lead in this new batch.
So I can solder LD(-) to IC pin at the other side, then can bypass UI.(no mode)
I have a plan to insert a small switch there.(multimode or single mode)

I'm waiting my heatsink to arrive now.

Season's Greetings!

SHIN

edit) To lengthen the spring, I solder another spring or small piece of metal on there.

Re: NJG-18, 3 mode driver for 445nm with single cell

Shin thanks for posting these drivers.:beer:

Do the DX ones have the C1 soldered? The ones I got from the USA seller link you posted had it already done but they are out of stock.

Re: NJG-18, 3 mode driver for 445nm with single cell

I must of bought the last one From US seller a few hours ago because when i placed my order they were there and now it says item not found.