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Need Help Choose LED Drivers

Need Help Choose LED Drivers

Need Help Choose LED Drivers

Hi, I'm designing a couple of different portable LED lighting systems (Li-Ion powered 18650 batteries) and I am searching for a manufacturer for the LED drivers. Below I have listed the specs of the different parts of the system. I need some ideas on which LED drivers would be best suited for this. I realize there are many directions that I can go, but I'm trying to balance functionality with cost since I'm planning to manufacture these lights.

Main Light System: Consists of 1 Cree XM-L2 running at up to 10W and on a separate channel - 1 Cree XQ-E LED at a maximum of 3W.

Sub Lighting System: Consists of 10 XQ-B LEDs running at up to 1 watt each (10 Watts). These LEDs need to be on a minimum of 1 channel but if the cost isn’t too much more I would like to put them on 2 or perhaps 3 channels. 4 Cree XQ-E LEDs running constant at up to 1W each and intermittent pulsing at 3W each. Lastly 2 Colored XQ-E LEDs at 3W each (6W).

Please let me know your ideas on drivers and any recommendations on how I can keep the costs down.


RE: Need Help Choose LED Drivers

There are soooOOO many different drivers you will need to sort thru them yourself, as we won't know some details that may make a big difference. I suggest you go to either Linear Technology or Texas Instruments. Both have dozens of offerings and both have design tools that will take all your info and spit out complete designs.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Need Help Choose LED Drivers

"...any recommendations on how I can keep the costs down."

If you haven't already, you might want to check out the sellers from China and Hong Kong on eBay selling all sorts of LED drivers and related items. Whatever you need to do to keep the costs down, they've been doing it for years.

For a few dollars and several weeks shipping you could get your hands on "prototype" winky smile reference designs; actual hardware.

RE: Need Help Choose LED Drivers

^^ Then watch it catch fire or just die on you after a few weeks.. The "Chinese" drivers are absolute junk..

RE: Need Help Choose LED Drivers

There's some truth in that, but maybe it might be a bit stale. My first two attempts to be an 'early adopter' of LED light bulbs ended in very early failure; but that was about five years ago. Lately everything in my increasingly LED-illuminated world has been perfectly reliable. The AC powered items made in China and sold on eBay do give me pause, as they're typically not actually meeting any standards. As opposed to the made in China items sold through the normal retail chain that probably actually do.

Even if this caution is valid and valuable, then it would still be worthwhile to buy in some samples of these 'defective' products to see what inexpensive parts they've selected, witness these manifold failure modes, so that one's design can benefit from the lessons learned. The cost is negligible. The only real downside is the four weeks for delivery.

The OP was asking about inexpensive. It would be difficult to avoid seeing how the Chinese do it. I couldn't even mail back to them for the same cost as what they sell us with free S&H. So they do understand low cost.

RE: Need Help Choose LED Drivers

Nothing has changed...All the "Chinese" do is copy someone elses design, use inferior/fake parts, make a few high volume runs and have insanely low labor rates.. Nothing to be gained there IMO..
Very little if anything on ebay in that realm is actually "designed" by them.. Its all copies/cheap junk,etc.. When a factory in China needs tools or power supplies or whatever they buy a good one.. Copy it.. make thousands and then rebrand the extras for anyone willing to buy a pallet full.

I've built numerous 1-off LED fixtures (from 1W to 100W LEDs) and so far have just avoided rolling my own drivers/pcbs due to the 1-off aspect.. I've been using off the shelf meanwell LPF (ac/dc) and LDD (dc/dc) series drivers.. The LDD's can be had for only a few dollars or less in any volume ($5 or so for 1 pc)
but if you are building a product for a market then any EE worth anything can easily cobble up a proper constant current driver.. There are TONS of IC's out there and plenty of application notes/reference designs,etc.. from reputable companies..

RE: Need Help Choose LED Drivers

Hi Guys, thank you for all the feedback. I should clarify that I'm looking just for the main driver controller chip and not the complete driver with mosfets, etc. My problem is that I don't know exactly what specs to look for. Coincidentally, Keith I've been dealing with Linear and they've been really helpful and seem to offer some great chips, but I'm just wondering if perhaps their offerings might be overkill. In other words perhaps I don't need all of the options that those chips come with. They are suggesting that I go with the a few LT3797 chips for everything.

I'm happy to sort through the different companies and their offerings but I just need some guidance as to what to look for. Any help would be appreciated.


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