DIY LED driver for reef lighting

[perikaruppan]

so to summarize the DIY drivers, using a 24V Power supply: (Driving the LEDS at 3.4V and at about 700mA)
NCP 3066 : Economical, 8 LEDS
ZXLD 1366: Expensive, 6 LEDS
CAT 4101 : Cheapest, 6 LEDS

is the above correct?

Also, another thought that i had, how about a 1A fuse in the output of the Driver to LEDs, so that we dont blow the LEDs? or even if one of the LED burns out, wont this help?

 

[der_wille_zur_macht]

so to summarize the DIY drivers, using a 24V Power supply: (Driving the LEDS at 3.4V and at about 700mA)
NCP 3066 : Economical, 8 LEDS
ZXLD 1366: Expensive, 6 LEDS
CAT 4101 : Cheapest, 6 LEDS

is the above correct?

Yeah, more or less. I'd add the following:

NCP3066: reasonable price, lots of components, all-through-hole design.
ZXLD: SMT-only
CAT: SMT-only, but relatively easy package, LOW parts count

Also, another thought that i had, how about a 1A fuse in the output of the Driver to LEDs, so that we dont blow the LEDs? or even if one of the LED burns out, wont this help?

Depends on the chip and overall configuration. Some of these ICs will shut down at or just above 1A anyways (thermal or overcurrent protection).

 

[der_wille_zur_macht]

Parts arrived. Just waiting on the boards now.

For those wondering about the sizes of the SMT stuff we're talking about. These are 1206 resistors:

Tiny, but not insurmountable.

This is the CAT4101:

 

[marspeed]

dwzm

i ordered the same parts what soldering iron do you use ?

Marc

 

[der_wille_zur_macht]

Right now my "good" iron is this Aoyue 937+:

http://www.amazon.com/Aoyue-937-Dig...ref=sr_1_1?ie=UTF8&s=hi&qid=1267221778&sr=8-1

It comes with a REEALLY fine tip which will probably be good for this work, but I don't like for big stuff like soldering the actual LEDs (not easy to get a large contact area). If anyone gets one of those irons, consider ordering some tips at the same time to save on shipping. Now I'm stuck - do I pay $9 shipping for a $3 tip, or just "suffer" with this less desirable tip? I'm a cheapskate so I've been doing the latter so far.

 

[marspeed]

i looked at that iron before i think i will get one

thanks DWZM

MARC

 

[SpacedCowboy]

CAT: SMT-only, but relatively easy package, LOW parts count

I'd add that I hand-soldered one of the CAT4101 boards with ease, and it's still running fine, a week later, having been on 24/7. Even the tab that you need to solder to ground that is underneath the chip protrudes out, so it's easy to solder to your ground plane by hand.

You don't have to use SMT resistor/capacitors if you don't want to either - that board (as you can see) uses through-hole components. You can in fact see the (0603) resistor I originally used in the top-left of the picture [grin]. That's a real git to solder by hand

Simon

 

[marspeed]

I thought that was a spec of dirt in the picture

 

[jeffs86GT]

Right now my "good" iron is this Aoyue 937+:

http://www.amazon.com/Aoyue-937-Dig...ref=sr_1_1?ie=UTF8&s=hi&qid=1267221778&sr=8-1

It comes with a REEALLY fine tip which will probably be good for this work, but I don't like for big stuff like soldering the actual LEDs (not easy to get a large contact area). If anyone gets one of those irons, consider ordering some tips at the same time to save on shipping. Now I'm stuck - do I pay $9 shipping for a $3 tip, or just "suffer" with this less desirable tip? I'm a cheapskate so I've been doing the latter so far.

I just PM'd dwzm the other day asking the same question because I couldn't remember where he posted what he used. If I had only waited another couple days it would have popped up again in this thread I'm ordering this soldering iron this weekend

Jeff

 

[der_wille_zur_macht]

I thought that was a spec of dirt in the picture

And that's why 1206 is the smallest package I'll attempt by hand! Even still, you need either blue-tack or tweezers or both.

 

[TheFishMan65]

Board Status

Board Status

Well, the parts are layed out. My baord will be about 6.5x1.5 inches. I only have about 3/4 inch squared for cooling, but as long as the current and/or voltage differential is small I will be ok. Still don't have exact prices, but I think it will be around $44 or $5.50 per driver. I think in quantity you could get the price down around $37

 

[shackscs]

Right now my "good" iron is this Aoyue 937+:

http://www.amazon.com/Aoyue-937-Dig...ref=sr_1_1?ie=UTF8&s=hi&qid=1267221778&sr=8-1

It comes with a REEALLY fine tip which will probably be good for this work, but I don't like for big stuff like soldering the actual LEDs (not easy to get a large contact area). If anyone gets one of those irons, consider ordering some tips at the same time to save on shipping. Now I'm stuck - do I pay $9 shipping for a $3 tip, or just "suffer" with this less desirable tip? I'm a cheapskate so I've been doing the latter so far.

Ok, spill the beans!!! How many of you went and ordered one for $50.00 from Amazon.com or SRA-Soldering?? C'mon admit it, you ordered one......I almost did. :spin1:

I need something better that the one I got from the rat shack that lasted not very long at all.

DER, what other size soldering tips would you recommend for both the SMT and the through hole boards??

Well, the parts are layed out. My baord will be about 6.5x1.5 inches. I only have about 3/4 inch squared for cooling, but as long as the current and/or voltage differential is small I will be ok. Still don't have exact prices, but I think it will be around $44 or $5.50 per driver. I think in quantity you could get the price down around $37

Pics?

 

[der_wille_zur_macht]

DER, what other size soldering tips would you recommend for both the SMT and the through hole boards??

It's a personal preference thing, really. I like small chisels since you can use the "point" for really fine stuff, or lay the chisel edge flat against larger stuff (solder pads on an LED star). Honestly I don't think you need different tips for different jobs, just one tip that you like and you'll find it's good for a range of work.

I ordered from Amazon but I don't think Amazon shows the full selection of tips vs. going straight to SRA.

 

[shackscs]

Yes, the SRA site has more to offer.

Will probably order from them directly.

 

[shackscs]

Even still, you need either blue-tack or tweezers or both.

Umm...What's blue-tack?

 

[der_wille_zur_macht]

That rubbery putty you use to hang up posters without damaging paint. It works for holding parts in place, too. Basically, you you a TEENY TINY little dot of it to hold a part in place while you solder one or two pads down. Then you pull off the blue-tack and solder the rest of the pads.

If you have steady hands you can just hold the part with tweezers but the blue-tack works really well for small stuff with a lot of pins close together - if you try to do that sort of part with tweezers, a tiny little flinch or shake can mean it lands crooked or the pins are on the wrong pads.

 

[stugray]

WOW - crazy!

Just because of this thread, I installed Eagle Cad free version & thought I'd do the tutorial....

I clicked RANDOMLY in the library for parts.

The SECOND part I clicked on ( RANDOMLY ) was the CAT4101....:-0

I think it is an OMEN.

Stu

 

[SpacedCowboy]

WOW - crazy!

Just because of this thread, I installed Eagle Cad free version & thought I'd do the tutorial....

I clicked RANDOMLY in the library for parts.

The SECOND part I clicked on ( RANDOMLY ) was the CAT4101....:-0

I think it is an OMEN.

Stu

Really ? What library is it in ? (do an 'info' on the part). I went and made my own up

Simon

 

[stugray]

EAGLE 5.7.0 Light - On Semiconductor - CAT4101 TO-263

Stu

 

[der_wille_zur_macht]

It's the first of the chips we're using that's in one of the OOTB libraries!