Drivers for new generation LEDs ?

lumen_eater

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A while ago I was planing on an MC-E based light for my room but than I saw those new luminus LEDs and decided to use those. They are pretty awesome but they have a major drawback, they need about 6 amps, I couldn't find an 6A led driver anywhere. Could I just connect multiple drivers in parallel? How would you go for driving those huge LEDs? (I'm specially interested in the CBM-360-W)
 

jtr1962

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I'd just make my own driver. Seriously. In fact, I just finished designing a new P7 driver for automotive uses. Since it uses a separate MOSFET I would imagine the output current could be scaled for anything within reason. I actually laid out the board so I could use D-PAK MOSFETs instead of the current SO3 just to future proof myself (and I had planned to use this same board to drive peltiers).

In general you can't parallel drivers. They won't necessarily share the current equally.
 

lumen_eater

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I thought of this before but I don't really know how to build an led driver my self . Is there some sort of a designing guide out there? Also I don't know how I could implement dimming in such an self made driver. Isn't there some sort of infinitive scalable driver ic available where I just need to hookup some MOSFETs, resistors and inductors to have every current I like ?
 

yellow

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You start www.national.com,
choose "Power Management"
and type in Your data in the grey mask on the right + hit "Start Design"

the search offers You a few of the ICs possible, out of which You decide which to take
(difficulty in soldering, efficiency, availability, several levels (adjustability), price, ...)
Then download the datasheet and read it.
Gives much info, step-to-step instructions and usually some basic circuit designs (with one that usually covers the needs one has)
 

zzonbi

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"Could I just connect multiple drivers in parallel?"

I connected 2, then 3 different constant current drivers in parallel, to test an xre, and it worked fine. The current summed up, just as voltage does when connecting constant voltage sources in series.
But where can one buy these Luminus leds?
 

jason 77

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You start www.national.com,
choose "Power Management"
and type in Your data in the grey mask on the right + hit "Start Design"

the search offers You a few of the ICs possible, out of which You decide which to take
(difficulty in soldering, efficiency, availability, several levels (adjustability), price, ...)
Then download the datasheet and read it.
Gives much info, step-to-step instructions and usually some basic circuit designs (with one that usually covers the needs one has)

Ok I played around a little bit with that web site.... only problem is it looks like they are all SMD parts they use.. and I mean TINY SMD parts... is there a way to switch them to "through hole" parts? I mean I guess I could look up individual replacement parts that are through hole... but there are some I can't find, Like the main IC in anything other than the SMD packet?
 

blasterman

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How would you go for driving those huge LEDs?

You can always use a computer PSU like I do when I need to drive a *lot* of high power LEDs. They have more current capacity than you could possibly use.

Problem is, you need to use resistors (big ones) on the 12volt side to get the proper forward voltage.

I'm currently honing up on my circuit knowledge so I can build my own dedicated supplies.
 

HarryN

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Ok I played around a little bit with that web site.... only problem is it looks like they are all SMD parts they use.. and I mean TINY SMD parts... is there a way to switch them to "through hole" parts? I mean I guess I could look up individual replacement parts that are through hole... but there are some I can't find, Like the main IC in anything other than the SMD packet?


The key is to use solder paste - not solder wire. There certainly are some very experienced people that can wire solder these tiny parts - but I sure can't.

Solder paste solves more of these problems than you can imagine - practice a bit, but it is a lot more loose than you can imagine. Rather than relying on me to actually be able to see and place and touch just right these tiny spots, SMT with paste just lets you somewhat glob it on and it tends to go to the right spot.

Flux + solder being designed for each other, plus a very clean board are important. Precision placement is not. I never use wire solder now that I have found paste.
 

lumen_eater

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OK i now played around awhile with the link above and most of the configurations I came up with didn't work (no parts found) … if I remember right the most powerful configuration was something in the range of 3point something amps (the SST-50-W goes up to 5 A and the SST-90-W up to 9A).
also you might have got me wrong : im not searching for an power supply, im searching for an constant current source that works of 12 or 24 V DC (so an psu wont solve my problems)
 

yellow

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usually all these SMD-parts have their "normal" versions also.
Should be mentionned in the datasheet (normally named almost the same with some extension for the SMD)

When playing with the site, I also noticed very very few - almost none - search hits, while I remember quite some to choose from. Has been much time I soldered drivers for myself. Finding all the parts, cost, guaranteed function, size, ..., that all screams "get a ready made driver".


there is another enterprise offering such a site. Dont remember the name.
Could it be "LT", or such?
 
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