DIY LED driver for reef lighting

Yeah, it is what I had on hand. Not perfect, but definitely does the job.

I was probably with in a reasonable range of temperature. I think it was the CAT4101 that used the thermal example of ambient at 60 C (140 F). If so then I was only running at their ambient design point. But I prefer cooler because I believe it will last longer and I don't want something around where I can get burned just by bumping it.

I am hoping to avoid the whole fan thing. That is a fall back, but if I don't have one I don't have to worry about it stopping. It will also make the fixture a little more efficient.
 
Any chance the Cat4101 boards can be put into seeedstudio's Pcb pool, so we dont have to order 10 at a time?

Interested if anyone has some spare boards, and Cat4101 IC too.
Mouser want $40 to ship to Aus =(
 
So I should follow this schematic,
forget the left hand side because I will use an arduino for the 5V then I should be alright?
For the PCB can't I just go about making my own using one of the many ways of etching one?
For Rset I use the data sheet's resistor table, then use the resistor value to set the current correct?
What do i do so i can control it with arduino with PWM?
I know how to use PWM, but I do not know if I just hookup it's PWM pin to the CAT4101,
or do I need(sorry reading this whole thread made em slightly forgetful) a form of transistor with the PWM input somehow?

Thanks for the help :)
picture.php
 
Last edited:
If you have way to etch it great. I did some years ago and it is just easier to get them made IMHO.
Yes you can use RSET from the table. I did a potentiometer so I could get my color to look right and so if i need to I can acclimate corals. You can get them for $0.80. They may have also have some use in controlling heat - still trying to figure that out. The problem is thta if you guess wrong, you either live with it or but new one at which point it would have been cheaper to just use the pot. Now maybe you have a bunch of 1% resistors lying around - I don't. I think you see my point and either way will work.
A arduino should just hook right grump PWM pin to EN/PWM and a ground line for reference. I have not tried this yet either, but that is my understanding.
 
Thanks for the clarification.
I am just a hobbyist that dabbles with electronics here and there,
so any help helps a lot :)

I don't mind taking more time since I'm only going to do two drivers for now,
plus I'm 17 and sort of budgeted.

I'll go ahead and use a 10k pot because I don't want to get things too hot,
plus I want to experiment whit it and I don't have anything resistors laying around.

The arduino thing makes sense,
really simple and should be fun to mess with.

I am assuming I don't need to use SMD parts other than the CAT4101,
I know it would be somewhat ghetto but the board won't be much bigger...
The bes method to find an equivalent from what I'm thinking is to look up the mouser part #'s given on the BOM,
then look for non SMD equivalent(like the capacitor is tantalum , ceramic or whatever and matches XXX specs, etc)
 
Sounds good. However last time I checked Future Electronics was about $1.60 and Mouaser was about $3.40. Of ourse for Hawaii shilling may make a big difference. You may alsow want to check digikey.
 
The shipping is more for future electronics,
maybe if I do 10 drivers sometime I'll go with them.
Thanks for the suggestion as any money saved helps.
For doing my own PCBs i was thinking of just using a Sharpie marker to do the traces.
When I'm done etching acetone will take the marker off easy.
Won't look great but if I have all the parts in hand I think can get it done well.
 
Cheapest I could find at mouser was $6.95 for one lb. I have ordered twice from future $9 so it sort of depends on what you need. Just in case one of missed something.
 
Thanks I'll add everything up and see what's cheapest.

I need to get some copper clad pcbs,
wire for the array, etching chemical and the parts,
plus courage to go further into the hole of spending on the light :)
 
I am unfortunately lost.
So how do I get the output from Eagle?
I know how to use Maya and Blender,
they are complex programs but eagle is confusing me.
 
I am sorry for asking another question.
After a few hours I fully understand how to get a usable image from Eagle.
However this is somewhat of an issue.
Where are the resistors and caps going?
They need to be grounded according to the schematic,
however I don't see a ground plane or jumpers,
or holes for them.
I'd appreciate the help since I have parts coming and am going to etch the PCBs when I get the parts when I understand this one thing.
Wherearetheygoing.png

Thanks,
Josh
 
I am 90% sure there should be aground plane one each side for cooling. Not real familiar with Eagle but check which layers are enabled - maybe? Can you produce gerber files with Eagle and look at them with a gerber view program (I think I used gerbview free online).
 
jm82792,
The dotted lines on the outline of the board are the outline of the two ground planes. They are just in transparent mode, that's all. So yes, it is invisible ground :)

For eagle, go through the sparkfun tutorials, they are quite helpful and will show you how to do a project from scratch.

THz
 
I just noticed. I thought there was a newer version where he fixed the labeling of his LED terminals. "L2+ L2+ L11 L1+" is not correct, but you can probably figure it out. The other reason I ask is I thought it was supposed to have more cooling vias around the CAT4101 or are they hidden also?
 
TheFishMan65 said:
I am 90% sure there should be aground plane one each side for cooling. Not real familiar with Eagle but check which layers are enabled - maybe? Can you produce gerber files with Eagle and look at them with a gerber view program (I think I used gerbview free online).
Click to expand...
I'll check into that,
I enabled all layers but am lost..

terahz said:
jm82792,
The dotted lines on the outline of the board are the outline of the two ground planes. They are just in transparent mode, that's all. So yes, it is invisible ground :)

For eagle, go through the sparkfun tutorials, they are quite helpful and will show you how to do a project from scratch.

THz
Click to expand...
I'm going to sparkfun and reading it now :)
Hopefully I don't have to learn the equivalency of Blender to get somewhere,
Blender took me 2 years to learn really well..

TheFishMan65 said:
I just noticed. I thought there was a newer version where he fixed the labeling of his LED terminals. "L2+ L2+ L11 L1+" is not correct, but you can probably figure it out. The other reason I ask is I thought it was supposed to have more cooling vias around the CAT4101 or are they hidden also?
Click to expand...

It's the newest one from google code "hpled",
I have no clue about why stuff isn't showing.
 
jm,

Those look fine.

EDIT - but definitely make sure you have the latest version if you will be getting a board house to make these, as the silk layer (which you didn't show) has some updates, and there are more vias. The vias aren't showing in your copper layers because they are part of the GND planes. If you look at your drill file you should see the vias.
 
PS - good thought about asking Seeed to add to their board pool, though my experience is that they'll price it high enough that unless you reeeeallllly just need one or two, you might as well order a whole stack anyways. I know they've cut at least 6 or 7 orders of these to date so they're probably on the verge of adding it themselves. :lol:
 
I am planning on etching my own.
I've got a dozen 6X7 doubled sided 2oz clads for cheap($12),
some etching solution and such.
I'm hoping with some trail and error it should work.

I should get my Mouser and On Semi stuff this Monday :)

I think etching my own should work,
I just need to figure out where to get to borrow a laser printer.
 
You must log in or register to reply here.

Similar threads

C
DIY Stand for Flatback Hexagon Tank
Replies
2
Views
787
Drummer98
Drummer98
T
Looking for a specific tank build - EZTube.com sent me here
Replies
6
Views
548
Reefing102
Reefing102
Emanuel92
What lighting for S. haddoni and E. quadricolor?
2
Replies
20
Views
1K
Hong Kong
Hong Kong
C
Scored a complete setup for $100
Replies
13
Views
1K
griss
griss
R
Red tufty algae - Asparagopsis - any expert advice for removal?
Replies
14
Views
2K
rallibon
R
Back
Top