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

[dethlore]

Hmm... how did I miss that? Anyway, it looks like it has a rather large footprint.

Truly it does look like a large footprint. My thoughts on this is that I would want a large heatsink for anything using 1-3A, and I can get my hosts custom machined to allow a little extra room for this ( I think hosts look better longer anyways )

But you are right. I think this could have been made a little smaller.

 

[qumefox]

Look at the dimensions. It's the same size as the NJG-18's.

But... May be ok for a multiwatt 808nm but show me a 445 diode that will take 3A. It might be workable to drive two paralleled though.

 

[dethlore]

Look at the dimensions. It's the same size as the NJG-18's.

But... May be ok for a multiwatt 808nm but show me a 445 diode that will take 3A. It might be workable to drive two paralleled though.

I WISH I could show you a 3A 445 diode! :yh:

The difference is:
NJG
Dimensions: 0.67 in x 0.67 in x 0.4 in
Weight: 0.18 oz

Other Driver
Dimensions: 0.87 in x 0.87 in x 0.55 in (2.2 cm x 2.2 cm x 1.4 cm)
Weight: 0.35 oz (10 g)

1/5" Pretty different for a pointer... maybe not much. Also this other driver only has low med high. just the 3 modes. But I saw it was pretty similar so I thought I'd ask if anyone had tried this and see how it compares.

 

[Wolfman29]

Can this thing can be adjusted to output lower current?

 

[dethlore]

It has a high low and fast strobe... so there is a low. Not sure how much current... :S

 

[qumefox]

The low is just PWM on these types of drivers.

 

[lazeerer]

Has anyone had a go at this "3000mA" driver from DX?
$5.00 - 6-18V 3000mA 3-Mode Circuit Board for XM-LT60 Emitters - Flashlight Parts and Tools
I'm very curious to see if it would work well for a 445 (possibly a 3w 808nm)

No It doesn't work. Only ~500mW with 1 18650. Works with 2 cells but gets hot needs heatsinking.. Its larger too. Wont fit in a common host.

Look at the dimensions. It's the same size as the NJG-18's.

But... May be ok for a multiwatt 808nm but show me a 445 diode that will take 3A. It might be workable to drive two paralleled though.

Driver is 22mm in diameter.
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Can this thing can be adjusted to output lower current?

Yes.
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Edit:

It does 2.83A on High 1.5A on Low/Med and Strobe Full Power more or less. This is with 2x 18650.!!

Tested at 1.8A still needs heatsinking. Kinda hard with the board design. You need a large host to fit this driver in.

Makes a High Pitched Noise. You can get rid of this if you move the inductor away from the board. Again Needs larger host.

 

[qumefox]

Yeah I realized that after I measured one of my njg18's but i'd already been corrected by then.

 

[lazeerer]

Dint catch that. Sorry for repeating it.!

 

[LaZeRz]

Whos willing to sell me a NJG-18 set to 1650ma? I will add the heatsinking

Sorry for threadjack...

 

[rhd]

The NJG is awesome, but very inefficient.

If you have enough room for a battery that can provide enough current for an NJG set that high, then you could probably fit two cells and do a linear build that would actually be more efficient in this case.

At least, that would be my approach

 

[rocket689]

Whos willing to sell me a NJG-18 set to 1650ma? I will add the heatsinking

Sorry for threadjack...

The highest I've ever been able the set a njg-18 is ~1300ma; and it gets hot fast! Then thermal shutdown takes over.....

Edit; I agree with rhd....a linear setup would be way more efficient, if you can use 2 cells

 

[random person]

Sorry, don't have time to read 12 pages... Isn't this driver a voltage regulator? If your trying to run 445s at max your going to want a current driver right since there going to heat up? In addition, the voltage drop across a 445 1W isn't greater than a 3.7V lithium Ion. The equivalent of this drive for your function would be a single resistor in series with your laser. If your not going to bother with current limiting you mine as well direct drive with a resistor in series for there is no difference. Then again... if the limit of this driver is less then the max current you can pump through it, I guess it would work then.

 

[qumefox]

The NJG18 is a boost driver. However it's a CV driver instead of a CC driver and it's voltage output ratio is related to the input voltage. The result is as battery voltage drops so will the driver output.

These are LED drivers, so of course they aren't the best for LD's.. But that being said. 445's are robust enough to be able to work with these without many dangers. I've also run a 660nm LOC and a 12x 405nm diode off NJG-18's too. They aren't the best, but they're a cheap alternative to a microflexdrive when using a single Li-Ion.

 

[JaiNobeZ]

Me & Chez bought 2 of these drivers and had them shipped to Eudaimonium for our anniversary builds. The first one he used wasn't behaving right and then all of a sudden it exploded. Someone in one of the early pages reported a similar thing. He had trouble with the modes on the second one so he gave up.

Just saying, if you buy these drivers and you're working with them, wear gloves and goggles. He wasn't hurt, and i did apologise, but it could have been pretty nasty.

 

[qumefox]

The modes on these drivers are a PITA.. Your actually better off and safer just disabling them. Setting the initial current is also best done with the modes disabled. That way you don't have to guess about being in high mode.. and being wrong and frying something.

I did a build with one today actually, and the only reason I left the modes enabled is because they didn't give me any problems, and it was already in the mode group I wanted anyway.. which was high-med-low only.