TheFishMan65
New member
Pin 4 RSet should be 1.2 volts or so. Check the resistor sound like it is shorted and pin4 goes right to ground. What was the supply voltage?
DIY LED driver for reef lighting
- Thread starter der_wille_zur_macht
- Start date
Names Brucey
New member
I can speak from experience since I am the one Fishman helped out. On two seperate boards I was having issues that I couldn't trace back to anything other than one board showing continuity of PWM across all outputs, not just the appropriate one, and the other board showed continuity across the ground and the PWM. After tracing everything back on both boards and not finding anything, I started removing the CAT's one by one starting with the where I thought the problems were arising based on all my continuity testing. Low and behold, I had two CATs (one on each board that were bad). I have no idea whether I overheated them while installing or what but it solved the problem. Word of warning removing them. The back plane is easy to get up. The channels on the front are not. I ended up ripping my solder pad off on both boards on a couple of channels. I could have avoided this if I would have just cut the pins from the CAT and then removed them one by one but I was trying to salvage the CAT in case it was good. Point being, I would consider cutting the pins to remove them and just purchase some new CAT's because otherwise you risk ruining your board. Good luck. wing
Names Brucey
New member
Like others have said and sounds like you have done. Just start checking for continuity between everything and compare to the working boards. For me, I wasn't getting continuity between the CAT pins even though the CAT was clearly bad.
terahz
1x10^12 Hz
It could be any of the three chips. Since pwm and gnd are common, if any of the three shorts them, the others will appear shorted as well. Unfortunatelly that usually means the others are dead too. I had fixed 2 boards like this before. I would just put together another board if you have the parts and ditch this one.
If you just want to figure out the problem, try unsoldering the 3 chips and test them without the board and against a brand new chip. That will show you which or how many of them have gone bad.
If you just want to figure out the problem, try unsoldering the 3 chips and test them without the board and against a brand new chip. That will show you which or how many of them have gone bad.
TheFishMan65
New member
jtro, Reading your responses I am confused so just to clarify for folks. Measure resisance with no voltage applied to the board. You could damage your meter ohter wise.
I am not sure if you did. Don't take one out and then replace it. Check to see if you found the problem. It is possible that if you install a new one you might just damage that one also. Take it out and see if the problem goes away, if not take out the next one.
I am a electronics newbie...
So I really do appreciate any help that I get... and yes I have read all of the tread.
Thank you all that have created this I admire your skills.
I have a 800l tank which is currently run by PLC which was all DIY, time to move on.
I have the files for purchasing the 4101 3 driver boards and emailed seeedstudio.com and they said they are not manufacturing board at the moment and the minimum would be 100 when they do..!.... so can some one direct me to a place where I can get 10 boards please?
I am looking at 120 Led's and are using 2 x 24v - 6A power supplies, one for each color.
Also is there an up to date list of components for this build... as it is not stated in the summary on post 1167 by the great Fishman.
Sorry to be a newbie but I am looking forward to building these..
So I really do appreciate any help that I get... and yes I have read all of the tread.
Thank you all that have created this I admire your skills.
I have a 800l tank which is currently run by PLC which was all DIY, time to move on.
I have the files for purchasing the 4101 3 driver boards and emailed seeedstudio.com and they said they are not manufacturing board at the moment and the minimum would be 100 when they do..!.... so can some one direct me to a place where I can get 10 boards please?
I am looking at 120 Led's and are using 2 x 24v - 6A power supplies, one for each color.
Also is there an up to date list of components for this build... as it is not stated in the summary on post 1167 by the great Fishman.
Sorry to be a newbie but I am looking forward to building these..
TheFishMan65
New member
Well then you know I don't have expertise on the 3 version board. I think the google site has the current parts list. Did you check there? If not when someone post I will update the summary.
Seeedstudio changes the rules it appears - you might doube check. I think sever have tried i something. Boy I am not being much help. I use Gold Phoenix. They do 100 square inches - however many boards fit for around $100.
I think you are going to need some more power supplies. 120 LEDs at 6 LEDs per string is 20 string or 10 per power supply or about 500 ma (.5 amps) each,
Seeedstudio changes the rules it appears - you might doube check. I think sever have tried i something. Boy I am not being much help. I use Gold Phoenix. They do 100 square inches - however many boards fit for around $100.
I think you are going to need some more power supplies. 120 LEDs at 6 LEDs per string is 20 string or 10 per power supply or about 500 ma (.5 amps) each,
terahz
1x10^12 Hz
iTead Studio:
http://iteadstudio.com/store/index....ducts_id=173&zenid=ok1c920i1j9klh58s158u7ot06
They are even cheaper. I've used them a few times now and I'm fairly happy. Can't beat them for the price.
For part list, the BOM on the google page should work. It has only 3 parts
http://code.google.com/p/hpled/downloads/list
TheFishMan65
New member
You can also design in a potentiometer (variable resistor).
Fishman board was just hooked up no power.When I checked Resistance.Then with no wires hooked up.I ended up taking each chip off one at a time and found two of the cat4101 bad one did work on all spots but finally damaged the board so using one of my extra ones.
I do have another question on The cat4101 temperatures they seem to get pretty hot.How hot is to hot.Going to do some long term tests today and get some board temps I will post my results.
Thanks
Jim
I do have another question on The cat4101 temperatures they seem to get pretty hot.How hot is to hot.Going to do some long term tests today and get some board temps I will post my results.
Thanks
Jim
TheFishMan65
New member
They get hot, but if they get too hot they have termanl protection and sut don - the LEDs will blink. What version board do you have? I ended up adding a heatsink to mine and shipped it with later boards.
TheFishMan65
New member
Sorry I read that wrong, I read it as in you just hooked up one of my boards. No damage they just flicker some - from what I have seen and read.
Obi-dad
Active member
there is a procedure here someplace that helps you 'fine-tune' the power supplyi voltage to reduce the heat by only having the power supply voltage about .5 volts above the voltage dropped by the string of LEDs. The heat on my CATs went down after that. I also put TO-220 (10 cents apiece) heatsinks on my cats just to further reduce the temperature on them.
