Meanwell LDD driver: for those who want to dim to 0 using Arduino

[frogg21]

I use Cat5e ethernet wires for the LED strings. No issues at 1 amp, and easy cheap connections/sockets, cheap 8 conductor wire (4 strings of LED's per cable).

[nkd5024]

I've been stalking this thread for a while now and have noticed that there are a lot of people who are looking for a simple way to control their leds using the LDD drivers with/without an arduino.

I was thinking of making a pcb with space for 4 LDDs plus an arduino clone that would be programmable on the board. This would eliminate the cost/space of an actual arduino and could easily provide the 4 pwm channels for the meanwells, a ds18b20 for temp monitoring of the leds which then could control the fans. The firmware side could be super simple and just provide ramp on/ramp off or also include the weather functions that iIm putting into my controller. The cost of the board should only be around $14 more than the standard ldd breakout boards.

[bigguyuk]

Originally Posted by nkd5024

I've been stalking this thread for a while now and have noticed that there are a lot of people who are looking for a simple way to control their leds using the LDD drivers with/without an arduino.

I was thinking of making a pcb with space for 4 LDDs plus an arduino clone that would be programmable on the board. This would eliminate the cost/space of an actual arduino and could easily provide the 4 pwm channels for the meanwells, a ds18b20 for temp monitoring of the leds which then could control the fans. The firmware side could be super simple and just provide ramp on/ramp off or also include the weather functions that iIm putting into my controller. The cost of the board should only be around $14 more than the standard ldd breakout boards.

thats sounds ideal + possibly the option of more channels maybe ?

[nkd5024]

The atmega328 only has 6 pwm pins but I could break them out so if you wanted to run two more ldds on a standard ldd breakout you could do that. If you want more than 6 we'd have to add in a pwm chip which would add to cost. I was thinking of throwing on an optional rtc for anyone wanting more advanced code.

[007Bond]

Originally Posted by frogg21

I use Cat5e ethernet wires for the LED strings. No issues at 1 amp, and easy cheap connections/sockets, cheap 8 conductor wire (4 strings of LED's per cable).

I'm thinking about using cat5 also. What kind of distance do you have between your LED's and the drivers? Thanks---Rick

[O2Surplus]

Originally Posted by nkd5024

I've been stalking this thread for a while now and have noticed that there are a lot of people who are looking for a simple way to control their leds using the LDD drivers with/without an arduino.

I was thinking of making a pcb with space for 4 LDDs plus an arduino clone that would be programmable on the board. This would eliminate the cost/space of an actual arduino and could easily provide the 4 pwm channels for the meanwells, a ds18b20 for temp monitoring of the leds which then could control the fans. The firmware side could be super simple and just provide ramp on/ramp off or also include the weather functions that iIm putting into my controller. The cost of the board should only be around $14 more than the standard ldd breakout boards.

I've already posted something similar. It's the Typhon/LDD combo from a few hundred posts back.It costs a bit more to build than you proposed, but it's "caveman" simple to operate since it carries it's own firmware, an LCD, and menu driven GUI.

[jedo65]

Very nice!

(Eagle-Files available? )

[007Bond]

That look really clean!

[iced98lx]

that's basically ideal for anyone with 4 channels to control. Dead simple and stand alone.

[nemosworld]

not to change the subject, but i got an email from a vendor in my work email and when i checked it out, i found these:
http://www.micropowerdirect.com/Page...rod%20LED.html

what's intersting is that they go to 57 volts, i know you guys said that the ldd's work some special magic where we should only worry about current as the ldd handles the voltage, if that's true then clearly the ldd is better, however if voltage does play into things, then 57v would mean atleast 1-2 more leds per string correct?

[nemosworld]

Originally Posted by O2Surplus

I've already posted something similar. It's the Typhon/LDD combo from a few hundred posts back.It costs a bit more to build than you proposed, but it's "caveman" simple to operate since it carries it's own firmware, an LCD, and menu driven GUI.

I really been wanting to ask you if you had or was it possible to make a version with more channels, but then i felt like that was asking too much, thanks for all the hard work you have put in thus far.

[nixapatfan]

Originally Posted by cbatterman

Hmmm. Well, if no one has any extra 5-ups, does anyone want to go in together to get some ordered? I can place the order if anyone is interested send me a pm.

I'm interested in a couple of boards but I can't PM you yet.

[007Bond]

Originally Posted by nemosworld

not to change the subject, but i got an email from a vendor in my work email and when i checked it out, i found these:
http://www.micropowerdirect.com/Page...rod%20LED.html

what's intersting is that they go to 57 volts, i know you guys said that the ldd's work some special magic where we should only worry about current as the ldd handles the voltage, if that's true then clearly the ldd is better, however if voltage does play into things, then 57v would mean atleast 1-2 more leds per string correct?

When we going to see something with a higher current output than 1000ma?
Something like 1400ma... we can always dial them back. ---Rick

[Jodah]

I'm fairly certain someone in this thread was able to parallel the drivers to get higher current. Honestly though, unless you have a really deep tank, 1000mA is usually mroe than enough. most don't even need over 700mA.

[007Bond]

Originally Posted by Jodah

I'm fairly certain someone in this thread was able to parallel the drivers to get higher current. Honestly though, unless you have a really deep tank, 1000mA is usually mroe than enough. most don't even need over 700mA.

I never seen a definitive answer on the paralleling thing. I do have a deep tank as I'm sure others do also. My multichip led's can be run at 1400ma, so thats why I posted the question.Kinda like driving your Harley with a governor on it. You can get 1000ma or 300ma both at 4.37 @, so would sure like to see a 1400 and at 4.37. Would be to cool

[O2Surplus]

Originally Posted by 007Bond

I never seen a definitive answer on the paralleling thing. I do have a deep tank as I'm sure others do also. My multichip led's can be run at 1400ma, so thats why I posted the question.Kinda like driving your Harley with a governor on it. You can get 1000ma or 300ma both at 4.37 @, so would sure like to see a 1400 and at 4.37. Would be to cool

The question of whether or not LDD's can be driven in parallel has been answered. We know they can. The unanswered question is- How long will the LDD's last if you do? If anyone wants to try it for themselves, the wiring diagrams have been posted. I stopped testing the parallel drive configuration, as I didn't want to risk any damage to my LDD's. The way I see it- until MeanWell releases a higher powered version and you need a higher drive current ( 1000ma - 3000ma) Grab an LM3409 based driver.

[O2Surplus]

Originally Posted by nemosworld

I really been wanting to ask you if you had or was it possible to make a version with more channels, but then i felt like that was asking too much, thanks for all the hard work you have put in thus far.

I'm exploring all of the options available to add more control channels right now. The additional channels may require a complete redesign of the controller, so this may take some time....

[cbatterman]

I am hoping that rrasco, O2Surplus or someone else with a solid understanding of LED drivers and dimmers would comment on the specs of these drivers. What I found interesting was the suggested use of a 555 timer for true pwm dimming. Am I correct that the LDDs are being dimmed by lowering the current and not by turning them on and off really fast like the 555 would be doing?

Originally Posted by nemosworld

not to change the subject, but i got an email from a vendor in my work email and when i checked it out, i found these:
http://www.micropowerdirect.com/Page...rod%20LED.html

what's intersting is that they go to 57 volts, i know you guys said that the ldd's work some special magic where we should only worry about current as the ldd handles the voltage, if that's true then clearly the ldd is better, however if voltage does play into things, then 57v would mean atleast 1-2 more leds per string correct?

[Jodah]

If you're using the pwm channels from the arduino, it's true pwm. I could see it being possible to use the 555 timer on one of the digital pins perhaps.

The LDD's dim from a pwm channel, not by lowering the current. Hence why they're called constant current drivers. You can vary the voltage that goes into them, but that just dictates how many led's per driver you can have.

[O2Surplus]

Originally Posted by cbatterman

I am hoping that rrasco, O2Surplus or someone else with a solid understanding of LED drivers and dimmers would comment on the specs of these drivers. What I found interesting was the suggested use of a 555 timer for true pwm dimming. Am I correct that the LDDs are being dimmed by lowering the current and not by turning them on and off really fast like the 555 would be doing?

I read the spec sheet for those drivers and their comments about using the 555 timer too. My thoughts- Why bother with a simple chip like the 555 when a micro-controller offers all the "bells & whistles" for just a few $ more. Seriously- Who wants to manually dim their leds using a pot & a 555, when a micro-controller can do it for you?
The MicroPower drivers may be able to drive one more led than the MeanWell LDD-H, but the Meanwells are available & cheap, where as the Micropower units don't appear to be available any where just yet. They're Unabtainium right now. (Doesn't mean that I won't work on a PcB design for them too )

[Pailines]

Hello Guys,
Sorry to interupt a well conversed conversation, but i was wondering if anyone can look through my material list and see if i am on the right track.

I am going to use solderless led stars from a famed manufacturer, not sure if i can say their names or not, but it involves "LED" and some times can be bought in "groupbuys."

9 Solderless CREE XT-E Royal Blue (1.5A) ------------------------ 1-LDD-1000H

9 Solderless CREE XT-E Royal Blue (1.5A) ------------------------ 1-LDD-1000H

12 Solderless CREE XT-E White (1.5A) ------------------------ 1-LDD-1000H

2 Solderless True Violet LED - 405nm (700mA) ------------------------ 1-LDD-700H
6 Solderless Hyper Violet LED - 430nm (700mA)

3 Solderless Deep Red - 660nm (700mA) ------------------------ 1-LDD-700H
3 Solderless Turquoise - 495nm (700mA)
3 Solderless CREE XP-E Blue (1A)

3 Solderless Deep Red - 660nm (700mA) ------------------------ 1-LDD-700H
3 Solderless Turquoise - 495nm (700mA)
3 Solderless CREE XP-E Blue (1A)

2 Solderless Royal-Blue Moonlight (350ma) ------------------------ 1-LDD-300H


4x Meanwell LDD-1000H LED Driver ------------------------ 1 extra driver each for backup, in-case i f-ed up some of the drivers..
4x Meanwell LDD-700H LED Driver
2x Meanwell LDD-300H LED Driver

1x 350 Watt, Single Output, SE-350-48 from Mean Well

8x IC & Component Sockets 24P TIN PIN TIN CONT(575-11044324) ------------------------ 2 extra for future if i wanted to add more led or not..
16x TERM BLOCK 2POS 3.81MM PCB GRN (651-1727010)

annnnnnnnnnnnnnnnnd using the famous PCB from your highness, either 2x4UP or 2x5UP, still debating... combined with a DIY adruino UNO controller.... am i missing anything??

I know the newest version of the PCB has a place for 10k.R, but not really sure which 10k R is good... and they come in reel of 5000..so...

[cbatterman]

Originally Posted by Jodah

If you're using the pwm channels from the arduino, it's true pwm. I could see it being possible to use the 555 timer on one of the digital pins perhaps.

The LDD's dim from a pwm channel, not by lowering the current. Hence why they're called constant current drivers. You can vary the voltage that goes into them, but that just dictates how many led's per driver you can have.

If the current isn't lower (but still constant) when the LDD is dimmed, how is it possible that folks in this thread are running a 700mA led on a 1000mA LDD as long as it is dimmed to 700mA or less? If dimming is done using pwm (not just a pwm signal) wouldn't putting a 700mA LED on a 100mA LDD burn up the LED even if it was dimmed since pwm delivers the full 1000mA to the LED in pulses?

[frogg21]

hey, thats a good question!

[marspeed]

they might be using a 700h ldd

[AMDphenomx4]

Originally Posted by cbatterman

If the current isn't lower (but still constant) when the LDD is dimmed, how is it possible that folks in this thread are running a 700mA led on a 1000mA LDD as long as it is dimmed to 700mA or less? If dimming is done using pwm (not just a pwm signal) wouldn't putting a 700mA LED on a 100mA LDD burn up the LED even if it was dimmed since pwm delivers the full 1000mA to the LED in pulses?

Ignoring whether the LED sees 1000mA or 700mA of current, here are some things to think about...

Overdriving an LED doesn't instantly kill an LED, though it may shorten its lifespan. Consider it like overclocking a CPU. While it doesn't kill it, you need better cooling to avoid breaking it and it will likely shorten its lifespan using more energy to output more computing speed. Of course, there are limits to both.

It should be noted that LEDs which have lens issues at the maximum rated current shouldn't be overdriven.

There's a quite relevant thread on Candlepowerforums on why the limits are where they are for LEDs. That thread link. LEDs are rated with a maximum current for best lifespan, which is likely at least 50,000 hours at 70% lumen output and though an LED may take more, having a hit on important specifications is bad.