der_wille_zur_macht
Team RC
Just checked and it's no longer on their website. OK, fess up, WHO BOUGHT THEM ALL??? :lol:
DIY LED driver for reef lighting
- Thread starter der_wille_zur_macht
- Start date
Just checked and it's no longer on their website. OK, fess up, WHO BOUGHT THEM ALL??? :lol:
TheFishMan65
New member
Well if you use the 6.3 with and 80% margin then 8 driver could be driven at .63 amps, with 6 driver you can drive at .84 amps about. Since I could not find the 8.3 amp PS I designed my board to run off of two 24 volt supplies - so if you really want 1 amp it is possible.
Which brings up a question. After reading the data sheet I don't think it is a problem, but I will get some opinions (with any other group I would be in deep ...). Anyone see a problem with turning off the 24 volt supply and leaving everything else connected (Vin at 5 volts and PWM runnng - or turned off). The dropout voltage is .5v so it should just shut down.
[EDIT]
Reread the data sheet. The drop out is related to Vin. But so is undervoltage lockout. So I would like to know the difference - if any one knows. I guess I will read it again.
Which brings up a question. After reading the data sheet I don't think it is a problem, but I will get some opinions (with any other group I would be in deep ...). Anyone see a problem with turning off the 24 volt supply and leaving everything else connected (Vin at 5 volts and PWM runnng - or turned off). The dropout voltage is .5v so it should just shut down.
[EDIT]
Reread the data sheet. The drop out is related to Vin. But so is undervoltage lockout. So I would like to know the difference - if any one knows. I guess I will read it again.
Last edited:
marspeed
Member
FishMan
i should have more precise what i meant about the power supply is finding one at 8 .3 i knew i should have bought them all.
they seem to have disappeared
also i was thinking maybe the board cost more with extra spaces i see that's not the case now
i like the idea of the on board voltage regulator maybe you could add a couple of jumpers to circumvent it for those using an arduino i got that idea from your first plan.
and yes those heat sinks cost a bundle saving money on it will be a plus
i should have more precise what i meant about the power supply is finding one at 8 .3 i knew i should have bought them all.
they seem to have disappeared
also i was thinking maybe the board cost more with extra spaces i see that's not the case now
i like the idea of the on board voltage regulator maybe you could add a couple of jumpers to circumvent it for those using an arduino i got that idea from your first plan.
and yes those heat sinks cost a bundle saving money on it will be a plus
HeneryH
Henery Hawk
Somone have a Cliff's Notes version of this handy? I'm pretty good with a soldering iron and mechanical construction but it would take years to read through all of these threads.
Maybe some of the kinks still need to be worked out but once things settle can someone summarize the results?
Maybe some of the kinks still need to be worked out but once things settle can someone summarize the results?
marspeed
Member
TheFishMan65
New member
marspeed
If you don't need the 5 volts just leave the regulator out. I will have at least two board only one with the 5 volt regulator. I will get 5 volts for the second board from the first. As long as the regulator doesn't get too hot you can keep adding boards.
If you don't need the 5 volts just leave the regulator out. I will have at least two board only one with the 5 volt regulator. I will get 5 volts for the second board from the first. As long as the regulator doesn't get too hot you can keep adding boards.
marspeed
Member
ok i see how that works another plus
der_wille_zur_macht
Team RC
Or, if people don't want the voltage regulator, they can use the design I'm prototyping, which won't have it.
You talking about a cliff notes for building your own drivers, or LEDs in general?
All those suppies gone... A sad day.. A day that may have made home spun controller boards substantially less cost effective..Since an essentially free power supply can no longer be assumed.
Time to perfect MWs driving parallel strings?
FWIW it's just the 8.3A model that's gone. They still have plenty of the $15 6.5A model.
der_wille_zur_macht
Team RC
Well, WORST case, Digikey has practically the same thing for ~$30, which is only a cost increase of 20 cents per LED.
shackscs
Super Premier Member
Ok, read the entire thread again since my Solaris is starting truly fail. I needed the refresher. 
Der, what PS are you planning on using for the double board design?
Since I have this 72 x 24 x 30 tank I too am going to need plenty of leds and I like this desgn due to fewer boards.
Also will this 500ma-700ma range be good enough penetration for a tank that is 30" deep and only has softies and LPS?
Der, what PS are you planning on using for the double board design?
Since I have this 72 x 24 x 30 tank I too am going to need plenty of leds and I like this desgn due to fewer boards.
Also will this 500ma-700ma range be good enough penetration for a tank that is 30" deep and only has softies and LPS?
der_wille_zur_macht
Team RC
shackscs,
Any power supply with a voltage correct for the driver and Vf of your LED string, within the limits of the IC.
For the dual driver NCP3066 design, a 24v supply works well. It will drive 8 LEDs per IC. It's important to note that the NCP3066 design I did is a boost converter, so the PS's voltage MUST be under the Vf of the LED string.
The mpja.com website has a 6.5A 24v supply that's only $15. You can drive three of the NCP3066 dual drivers on one of those if you keep the current below 600mA or so, with a reasonable headroom. That's 48 LEDs, three PCBs, 6 ICs, on one power supply.
This new design we're talking about is based on the CAT4101 IC. It's a slightly cheaper design overall. The PCB I've just sent to a board house for a prototype run has three ICs on it, so it can support three circuits, of 6 LEDs each, from a 24v supply (same one as above).
If you want to use the NCP3066 dual driver design, there's a set of EAGLE files, and a set of gerbers, and a BOM on the google code site I posted several pages back. I haven't published my CAT4101 design yet because I want to test it first.
Any power supply with a voltage correct for the driver and Vf of your LED string, within the limits of the IC.
For the dual driver NCP3066 design, a 24v supply works well. It will drive 8 LEDs per IC. It's important to note that the NCP3066 design I did is a boost converter, so the PS's voltage MUST be under the Vf of the LED string.
The mpja.com website has a 6.5A 24v supply that's only $15. You can drive three of the NCP3066 dual drivers on one of those if you keep the current below 600mA or so, with a reasonable headroom. That's 48 LEDs, three PCBs, 6 ICs, on one power supply.
This new design we're talking about is based on the CAT4101 IC. It's a slightly cheaper design overall. The PCB I've just sent to a board house for a prototype run has three ICs on it, so it can support three circuits, of 6 LEDs each, from a 24v supply (same one as above).
If you want to use the NCP3066 dual driver design, there's a set of EAGLE files, and a set of gerbers, and a BOM on the google code site I posted several pages back. I haven't published my CAT4101 design yet because I want to test it first.
shackscs
Super Premier Member
Thanks.
I must be having a time warp glitch or something. I thought I made the above post back when the talk was all about the double unit, now we are on the triple unit.
DER put me down for one of your protoboards once you get them tested. I am going to need quite a few, unless the focus goes to yet another type of driver.
I was just about to send over my order to have the double boards made, I guess I will wait and focus on the other parts of my fixture, ie frame heatsink, LEDs, wiring, etc.
Just out of curiosity what is everyone putting the driver themselves in? Project boxes?
Or have we not quite gotten to that yet?
I must be having a time warp glitch or something. I thought I made the above post back when the talk was all about the double unit, now we are on the triple unit.
DER put me down for one of your protoboards once you get them tested. I am going to need quite a few, unless the focus goes to yet another type of driver.
I was just about to send over my order to have the double boards made, I guess I will wait and focus on the other parts of my fixture, ie frame heatsink, LEDs, wiring, etc.
Just out of curiosity what is everyone putting the driver themselves in? Project boxes?
Or have we not quite gotten to that yet?
TheFishMan65
New member
I haven't gotten there yet. I am planning on using either L or U channel and may attach the driver to the side that do dissipate some of the heat. A project box might work. It kind of depends on how much heat (chich is current, voltage over the required for LEDs, etc) they generate.
der_wille_zur_macht
Team RC
It'll probably depend on your overall LED rig's structure as TheFishMan is hinting. Mine is going in a HUGE open space above my tank, since it's going to be built in to the wall. So the drivers will likely be in a project box up inside the hood above the LED rig. If I feel they need cooling, I'll use a ventilated box and/or put them on a heatsink or something. The main concerns I'd have would be cooling and keeping them out of salt spray or humid, salty air. And, as close to the LEDs and DC power supplies as reasonably possible.
HeneryH
Henery Hawk
What factors come into play here? I'm thinking of running a very slim unit above the tank and keeping the drivers below (running just the LED feed lines up to the fixture). Should I be concerned?
der_wille_zur_macht
Team RC
I'm not knowledgeable enough to predict outcomes for specific situations, just to know that longer leads can cause problems (as per the manufacturer's datasheets for many ICs we're playing with). To a certain extent I'm sure the manufacturers are being paranoid, but there must be some degree of sensitivity, or else they wouldn't have said anything.
FWIW, I've run my NCP3066 design with 3 - 4' of cable between the power supply and the driver, and another 4 - 5' between the driver and the LEDs, and it seemed to perform fine.
So, I wouldn't design a system where, say, the drivers were on the floor of the stand and the cables running to the LEDs went over 3' to a wall, up 8' in the the wall cavity, out 3' in the ceiling, then down 3' to the LED array. But, if I had the drivers 5 or 6' away, I wouldn't lose sleep.
FWIW, I've run my NCP3066 design with 3 - 4' of cable between the power supply and the driver, and another 4 - 5' between the driver and the LEDs, and it seemed to perform fine.
So, I wouldn't design a system where, say, the drivers were on the floor of the stand and the cables running to the LEDs went over 3' to a wall, up 8' in the the wall cavity, out 3' in the ceiling, then down 3' to the LED array. But, if I had the drivers 5 or 6' away, I wouldn't lose sleep.
TheFishMan65
New member
I can mention some of the problems, but not sure how big a deal it is. The to wires running next to each will some capacitance, longer wires more capacitance. This is probably a good thing for us, but I am not 100% positive.
Also a long wires is an antennae. So if you had a strong enough transmitter and at the right frequency this could change the voltage and maybe fry and LED. I don't think this is likely.
Both of these are a bigger concern in things like computers and you actually have to watch the length of the traces on PCB. Also a problem with high voltage AC. The reason they run 3 lines so far apart is to keep the capicitance (sort of ike a short for AC) down.
Having said this we are not in either of these modes, but if your PWM has a long lead you may have an issue.
Also a long wires is an antennae. So if you had a strong enough transmitter and at the right frequency this could change the voltage and maybe fry and LED. I don't think this is likely.
Both of these are a bigger concern in things like computers and you actually have to watch the length of the traces on PCB. Also a problem with high voltage AC. The reason they run 3 lines so far apart is to keep the capicitance (sort of ike a short for AC) down.
Having said this we are not in either of these modes, but if your PWM has a long lead you may have an issue.
