DIY LED driver for reef lighting

[new2SW]

Yes, and minus goes back to the pin (1 ?) on the CAT.

From your picture in post 2098. try the following.

1) Move the yellow and black wires over to the connector for LED 5.
2) Connect the +5 coming off the board to both of the PWM on that side (A and C)

I got a driver to work before having to leave for work. I did find a couple issues. Firstly according to the schematic LED1 is controlled by U2, LED2 by U3, etc. However, on the board the labels are backwards in that LED1 is actually by U10. I don't know if this is known or not or if it had been mentioned before. I began running continuity checks on all the pins for all eight drivers and found that the #5 pin on the chip driving LED1 (U10 on the board) actually wasn't soldered down to the board(bad soldering on my part). I know that was part of the problem, but as you had suggested I also jumpered the two PWM channels together (B and D) for this particular channel. I'll pull the jumper out tomorrow when I get home and see if the lights still work.
I dropped my supply voltage to 19.8V and was in the process of ramping the LEDs up to 800mA when I had to finally leave for work.

 

[TheFishMan65]

Glad you got it working. I will have to double check the schematic. I have tweaked the circuit board a little so perhaps they don't match.

 

[terahz]

Just realized I haven't shared the lm3409 v0.5 files.

All files can be found here:
http://joro.geodar.com/code/LM3409 v0.5/

or as one file:
http://joro.geodar.com/code/LM3409 v05.zip

 

[slobodan]

Thanks Firechild .. that is exactly what I had in mind....

 

[slobodan]

ups.. double..

 

[slobodan]

Thanks terahz for sharing your files.. Sent you PM regarding your ver. 4 boards that you might have laying around.

 

[currymuetze]

Just realized I haven't shared the lm3409 v0.5 files.

All files can be found here:
http://joro.geodar.com/code/LM3409 v0.5/

or as one file:
http://joro.geodar.com/code/LM3409 v05.zip

Hi Terahz,

what about soldering a few and sell them here or on ebay?
I am looking for some drivers with about 2000mA and PWM (and If I read correctly, thats both what your LM3409 design delivers right?) but I dont think I could solder them myself. A step by step soldering tutorial would help for people like me but guess thats too much expectation :hmm4:

Anyways good work - waiting for some ebay auction
Cheers
Thorsten

 

[der_wille_zur_macht]

It's best to keep discussions about sales of stuff out of these threads, according to the regulations of the forum.

Thorsten, this stuff is not super easy soldering, but it's also not rocket science. Look on Google or youtube for SMT soldering tutorials - there's TONS of great learning materials out there and an hour spent searching and watching videos will teach you all you need to know. If you can solder an LED array together, this should not be that much harder - it's DIFFERENT technique, but not that hard.

 

[rrasco]

I have been toying with building a DIY driver for some time, I finally found this thread earlier this week with the help of DWZM (thanks!) and now that I have the PCB layout for the CAT4101, I need some recommendations and clarification on a few things. I tried to read as much as I could, but at about 30 mins per page, there was no way I was going to make it.

I am planning a 72 LED system. How do you hook up multiple of these boards since they only drive 6-8 each? Also, I would like to use one power supply, or as few as possible. Can someone recommend a power supply and instruct me how to wire it up for multiple drivers? I am planning to use the bridgelux LEDs with a forward voltage of 3.6v.

Also, did anyone have these boards made in bulk...or are we on our own in that regard?

 

[O2Surplus]

I have been toying with building a DIY driver for some time, I finally found this thread earlier this week with the help of DWZM (thanks!) and now that I have the PCB layout for the CAT4101, I need some recommendations and clarification on a few things. I tried to read as much as I could, but at about 30 mins per page, there was no way I was going to make it.

I am planning a 72 LED system. How do you hook up multiple of these boards since they only drive 6-8 each? Also, I would like to use one power supply, or as few as possible. Can someone recommend a power supply and instruct me how to wire it up for multiple drivers? I am planning to use the bridgelux LEDs with a forward voltage of 3.6v.

Also, did anyone have these boards made in bulk...or are we on our own in that regard?

You'll need 12 Cats to drive 72 leds. Depending on your color mix, it's best to dedicate a driver board and power supply for each color. For example- Say your led ratio was 2:1, royal blue versus white. 8 cats and their own dedicated power supply would be needed to drive the royal blues. Another 4 cats and their own supply would be utilized to drive the whites. This is arrangement is necessary because of the differences in Vf between different color leds. The Cat4101 operates cooler/ more efficiently if the power supplies voltage can be adjusted down to just .5-.8 volts over the led strings
total Vf.
Since you know that you'll need to drive 12 cats total just design your driver boards to contain a number of cats that can be multiplied into twelve. eg.. 1,2,3,4,6. Pick a number that works with your desired color ratio in mind and design a driver board for yourself.

 

[rrasco]

Not sure of my ratio, either 1:1 or 2:1. I thought most people opted for 1:1; I've seen plenty of discussion about it just have not put too much thought into it, was just planning to go 1:1 unless anyone thinks that is a bad idea.

Since you know that you'll need to drive 12 cats total just design your driver boards to contain a number of cats that can be multiplied into twelve. eg.. 1,2,3,4,6. Pick a number that works with your desired color ratio in mind and design a driver board for yourself.

I'm sorry, that just threw me off. What is the purpose of the number that is divisible by 12? Once I pick a factor of 12, what do I do with it?

 

[NanoNana]

So is there an updated worksheet for the v5? Nice work too!

 

[jedidog1]

Questioner for all you running your diy drivers and leds.
What are you running your leds intensity at ? For me im running 2 rb to 1 wm
blues are at 1 amp and the whites are at 450 milliamp i like a little more blue and im running 60 leds on a 75.
There about 12 inches above the tank and i think it just might be to much as some of the sps frags are starting to look washed out bleached , Iv noted that when people are running AI there only running about half power and Ai have cree in there fixtures too same as are diy.
I dont have a par meter to measure the leds but i might have to find one to borrow.
And the leds have been on the tank for 8 months know.

 

[slobodan]

Hey terahz, sent you PM..

 

[pandimus]

Not sure of my ratio, either 1:1 or 2:1. I thought most people opted for 1:1; I've seen plenty of discussion about it just have not put too much thought into it, was just planning to go 1:1 unless anyone thinks that is a bad idea.



I'm sorry, that just threw me off. What is the purpose of the number that is divisible by 12? Once I pick a factor of 12, what do I do with it?

basically he is saying that you just decide how many driver boards you want.. for instance 3 driver boards would have 4 cats each on them.. or 6 driver boards would have 2 cats each..

 

[TheFishMan65]

Each CAT can drive at least 6 LEDs. You might get 7 with the XM-Ls maybe even the new XT-E (not real familiar with those). So for 72 LEDs youe need about 6 CAT drivers. I think he had a type unless my board is designed in 4 driver boards with 3 CATs each

What type of LEDs are you planning to use? That will help decide the ratio.
XR-E (old old old) were suggested at 1:1
XP-E and XP-G are suggested about 2:1
XP-E and XM-Ls are 3 or 4 :1
XT-E and XM-L I am guessing will be 3:1

XE-E are 20% brighter than XP-E I think. Anyone else having problems with the CREE site?

 

[TheFishMan65]

Each CAT can drive at least 6 LEDs. You might get 7 with the XM-Ls maybe even the new XT-E (not real familiar with those). So for 72 LEDs youe need about 6 CAT drivers. I think he had a type unless my board is designed in 4 driver boards with 3 CATs each

What type of LEDs are you planning to use? That will help decide the ratio.
XR-E (old old old) were suggested at 1:1
XP-E and XP-G are suggested about 2:1
XP-E and XM-Ls are 3 or 4 :1
XT-E and XM-L I am guessing will be 3:1

XE-E are 20% brighter than XP-E I think. Anyone else having problems with the CREE site?

 

[NanoNana]

I've seen a lot of people with extra CAT4101 boards, is anyone willing to send some my way? I'm happy to reimburse you. I know I can order them but I'd rather skip the lead time if I can.

 

[O2Surplus]

I recently got another batch of driver boards based on the LM3409 and finally soldered one up. This board measures 70mm x 75mm, so it does leave a lot of real estate for adequate cooling(Thanks- Kcress). My target current for this driver was 2200 ma maximum, and when tested was right-on. I set up this board for analog current adjustment and PWM dimming. I wired in a 250K ohm pot to the Vadj pin, so the maximum current can be lowered from 2200ma- to whatever drive current is desired, and then PWM dimmed further down from there. I let the diver run the other day, for a few hours, under full load and the Mosfet didn't even get warm! I also played with differing levels of Analog vs. PWM dimming and nothing weird happened- pretty cool! Take a look-

 

[jrdonnellyjr]

I recently got another batch of driver boards based on the LM3409 and finally soldered one up. This board measures 70mm x 75mm, so it does leave a lot of real estate for adequate cooling(Thanks- Kcress). My target current for this driver was 2200 ma maximum, and when tested was right-on. I set up this board for analog current adjustment and PWM dimming. I wired in a 250K ohm pot to the Vadj pin, so the maximum current can be lowered from 2200ma- to whatever drive current is desired, and then PWM dimmed further down from there. I let the diver run the other day, for a few hours, under full load and the Mosfet didn't even get warm! I also played with differing levels of Analog vs. PWM dimming and nothing weird happened- pretty cool! Take a look-

do you sell these?