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FrozenGate by Avery

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

Re: NJG-18, multimode boost driver for 445nm

I just used one to complete my Jayrob Pocket Mini Chrome build.
(Because the Flexdrive I ordered over a month ago still hasn't arrived...these took 4 days from that US supplier, and were $6....)

It works beautifully!

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Re: NJG-18, multimode boost driver for 445nm

I think the 1W 445's are about all this driver is suitable for... Maybe high power 405's as well but I think that would be kind of iffy. The spec sheet kind of indicates the driver will buck as well but after playing with it on a test load and with a sacrificed LPC-815 LOC, it certainly wont buck enough to drive a red. The minimum I could get the current down to is 630mA or so.. which is instant LED for a LOC.
 
Re: NJG-18, multimode boost driver for 445nm

Thats probably not so horrible, since we have similarly priced boost drivers for LOC current ranges.
 
Re: NJG-18, multimode boost driver for 445nm

OdicForce has two boost drivers that are around $6 each. In my experience, they essentially hit right on the ~400mA mark as a max.

In my mind, the only range we're really missing for a cheap boost driver, is from the ~400mA to ~600mA mark (IE, 12x diode range?)
 
Re: NJG-18, multimode boost driver for 445nm

These NJG-18's will probably work for higher power bluray diodes. The problem I was running in to with the LOC's is these drivers won't buck(in 100% on mode). Therefore it wont cut the voltage any lower than Vin - the driver's overhead. Which with a fully charged Li-Ion is around 3.5v.. at which a LOC draws around 630mA.. which kills it.

Blurays should work because of the diode's higher Vf. You won't be running in to the bottom voltage rail with the driver, therefore you should be able to turn the current down a good bit lower than 630mA.

I think this could possibly be made to work with a LOC with the addition of a diode string in series with the LD to increase the voltage drop the driver is seeing, to get it up in the range where the the Vf is greater than the Vin so the current can be properly adjusted.

My main goal wasn't just 'cheap driver' I was more after the modes than anything else.
 
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Re: NJG-18, multimode boost driver for 445nm

These NJG-18's will probably work for higher power bluray diodes.

When I hook one of these up to a test load set to blue(6 diodes) the driver shuts down. I had also read somewhere that the driver has a protection in it if the voltage demand goes to high it will shut off which is what I was assuming was happening. So I am not sure it would actually work with a 405. Any thoughts?
 
Re: NJG-18, multimode boost driver for 445nm

The spec sheet says it should output up to 7V. However, it may have limits as to how far it can boost voltage. 6V out with 4.2V in might not be possible. I don't have any 12x's left atm to test with and I don't have time right this moment to dig out the test load again.

Though keep in mind that the NJG-18 is a constant VOLTAGE driver, not a constant CURRENT driver.. If you want to accurately set the output current, you need a test load that is fairly close to the Vf of the actual diode you plan to use. Though since the pot is easy to get at with most builds using it, an easier practice to me is to just use a test load to verify that the driver is set to a safe level in high mode, then wire the LD and slowly crank up the power while watching the output on the LPM until you get the output about where you want it.
 
Re: NJG-18, multimode boost driver for 445nm

Neither do they like crocodile's teeth.:D
They love soldered connections though!

The current is higher on the battery side, due to the driver needing to boost voltage.
But 3A for that little bit of boosting?
Sounds like a terribly inefficient design!

So when setting drivers like the Micro Flex V5 or any others we should NOT use alligator clips but solder the connections instead? Otherwise we could be setting the current too high?:)
 
Re: NJG-18, multimode boost driver for 445nm

I have order these
sku_7882_1.jpg

from dealextreme. Are these the same as the NJG-18 drivers you guys are discussing here? because i really would like to try these out. unfortunately this happens to be the first order ever from them that has literally dissappeared has these were ordered jan.3rd and has not arrived.

In the meantime though, (sorry if i threadjacked) i have had success with the sandwich shoppes LED drivers that also are boost and can hit 1.5A (the one i got was cheapest and limited to 1A) heres a link to that thread i made:
http://laserpointerforums.com/f67/boost-led-driver-445-works-1-x-18650-1a-61246.html

Its really small and fits in the pill of guidesman all snug plus in that thread you see the aluminum star i cut in half and use as a heatsink.

I really wish DX wont lose my 2nd order of the NJG drivers because i plan on experimenting with them as shin has done to push some juice outta them and possibly make it "safe" for even the sensitive 12x BR laser diodes. as far as heatsinking, i gotta love those aluminum stars for LEDs from DX, 2 bucks for 3 and they sink heat from these round type drivers pefectly.
 
Re: NJG-18, multimode boost driver for 445nm

DX's takes a while to ship and once it ships its still pretty slow. Im still waiting on orders to ship that I made before Christmas (12/23)
I have order these
sku_7882_1.jpg

from dealextreme. Are these the same as the NJG-18 drivers you guys are discussing here? because i really would like to try these out. unfortunately this happens to be the first order ever from them that has literally dissappeared has these were ordered jan.3rd and has not arrived.

In the meantime though, (sorry if i threadjacked) i have had success with the sandwich shoppes LED drivers that also are boost and can hit 1.5A (the one i got was cheapest and limited to 1A) heres a link to that thread i made:
http://laserpointerforums.com/f67/boost-led-driver-445-works-1-x-18650-1a-61246.html

Its really small and fits in the pill of guidesman all snug plus in that thread you see the aluminum star i cut in half and use as a heatsink.

I really wish DX wont lose my 2nd order of the NJG drivers because i plan on experimenting with them as shin has done to push some juice outta them and possibly make it "safe" for even the sensitive 12x BR laser diodes. as far as heatsinking, i gotta love those aluminum stars for LEDs from DX, 2 bucks for 3 and they sink heat from these round type drivers pefectly.
 
Re: NJG-18, multimode boost driver for 445nm

Your post doesn't provide a link to the driver purchase page. Can you direct us?
 
Re: NJG-18, multimode boost driver for 445nm

*edit* I was kinda iffy on posting here about a different kinda of driver but if you are interested the thread i linked back there has been updated with some more info and a link.

oh ok got it HERE

I wasnt sure if i was allowed to make links to someone's business like that. but i guess if he doesnt complain :whistle:

anyways i would like to mention that i got the blank version where you have to solder resistors for the current you want, but they have fixed versions as well.
 
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Re: NJG-18, multimode boost driver for 445nm

I'm pretty sure thats ok in general.

I guess it's kind of a thread jack here, but it seems in good faith. I think most ppl in this thread would find it interesting. I couldn't find their boost driver that could hit 1.5 though?
 
Re: NJG-18, multimode boost driver for 445nm

ohh sorry folks, i was kinda of idiotic when i posted. apparently they have a maximum output of 1A of all if not most of their drivers. it appears to be a tps61030 ic driving all of these. so 1A limit is at the IC. but luckily they are cheap enough to drive 2 in parallel for 2A. and then heatsinking them is easy since they are flexdrive small.
 
Re: NJG-18, multimode boost driver for 445nm

back on topic though, if these NJG-18 drivers from DX do actually get here... you guys are measuring 3A+ draw at the batteries! dang, so much for any battery except a 18650 or bigger...

because of the cost and size of these things i was hoping to use them to fill all these empty hotlights i got from Matt. but those hosts can only fit a 18500 and even thats rated at only 1300mAh. u think 2.5C draw on that battery would be bad?
 





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