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

[pwreef]

This is a little test video I made using Meanwell LDD-1000H and Bridgelux BXRA-40E2200 Neutral White array:

The array itself is very powerful, so its not going to dim to moonlight brightness, but regular 3W LEDs do. They barely glow at 1/255 level. Enjoy!

[bhazard]

This is a little test video I made using Meanwell LDD-1000H and Bridgelux BXRA-40E2200 Neutral White array:

The array itself is very powerful, so its not going to dim to moonlight brightness, but regular 3W LEDs do. They barely glow at 1/255 level. Enjoy!

 

You just opened my eyes into building a seriously nice DIY array for my 120 gallon I've been looking for affordable 0 dimming options forever.

[jT415Gz]

This is a little test video I made using Meanwell LDD-1000H and Bridgelux BXRA-40E2200 Neutral White array:

The array itself is very powerful, so its not going to dim to moonlight brightness, but regular 3W LEDs do. They barely glow at 1/255 level. Enjoy!

Oh ah oh! That controller looks sweet, and even sweeter that it will dim all the way down to 0.

How much would you charge to build a controller like that for me? PM me.

[jedimasterben]

What power supply did you use to power them?

[keli]

Do you have a parts list somewhere? I'm particularly interested in what touch panel you are using..

[bhazard]

What power supply did you use to power them?

 

You can use any switching power supply up to 48v. The power supplies stevesleds sells would work, although you could save money by running less of these at 48v instead.

 

I just grabbed a 400w 48v 7.3a one from ebay for around $50 for my next build. IMO these drivers are better than the ELN-60-48-D/P, and much cheaper overall. The ELN's run at a slightly higher current though which is nice for XT-Es.

[pwreef]

Do you have a parts list somewhere? I'm particularly interested in what touch panel you are using..

LCD:

http://www.ebay.com/itm/3-2-inch-TFT-LCD-M...ME:L:OC:US:3160

You also need a RTC/LCD shield

I used this one

http://iteadstudio.com/store/index.php?mai...products_id=236

But its no longer available. Their newest version does not include RTC. So you have to buy a separate RTC shield.

If you want to learn more about the controller follow the link in my video.

[mpg732]

Would you be willing to share your code?

 

Never mind, I just found the link. Thanks

[bhazard]

This is the whole kit:

http://www.ebay.com/itm/SainSmart-Mega2560...=item4168c41ead

 

You will also need an RTC module and 3 temp sensors. There is a manual on the wiki page that is a must read.

 

RTC

http://www.ebay.com/itm/1PCS-I2C-RTC-DS130...=item41693537d8

 

DS18B20 Temperature Sensor

http://www.ebay.com/itm/Waterproof-Digital...=item27c5beb29a

[phild3791]

I've been looking at the data sheet for this and have a few questions.

1. the current isn't adjustable?

2. for better efficiency you match the power supply voltage to the number led in your string, but theoretically you could run 1 led @ 48v ?

3. the only way to dim them, are with a PWM signal?

4. the arduino has a 5v PWM signal. have there been any issues?

 

Thanks

Phil

[jedimasterben]

I've been looking at the data sheet for this and have a few questions.

1. the current isn't adjustable?

2. for better efficiency you match the power supply voltage to the number led in your string, but theoretically you could run 1 led @ 48v ?

3. the only way to dim them, are with a PWM signal?

4. the arduino has a 5v PWM signal. have there been any issues?

 

Thanks

Phil

1) not in the 'normal' way like the ELN drivers, this has to be adjusted via dimming.

2) yes, and no. Match the power supply voltage as best you can (if it saves you money, that is, to get a less voltage-heavy supply), but a single LED will still only pull however many volts it needs, not the full voltage.

3) right.

4) that i don't know, but it can be converted to a 10v signal like on my Typhon controller.

[bhazard]

I've been looking at the data sheet for this and have a few questions.

1. the current isn't adjustable?

2. for better efficiency you match the power supply voltage to the number led in your string, but theoretically you could run 1 led @ 48v ?

3. the only way to dim them, are with a PWM signal?

4. the arduino has a 5v PWM signal. have there been any issues?

 

Thanks

Phil

 

1. They have 350mah 600mah 700mah and 1000mah versions of the drivers. Just choose the type you need.

2. Based on what the datasheet says, I'd say so, more like 2 leds.

3. PWM only

4. Arduino goes up to 6v and this goes up to 6v. Perfect match, almost like it was designed with it in mind.

[Cintax]

I use these on my LED array. Very nice drivers. They can be ordered from Mouser for a very good price.

 

I used LDD-1000H and LDD-600H for my build.

 

http://www.meanwell.com/search/LDD-H/LDD-H-spec.pdf

 

There are also lower voltage versions which are a third of the size.

 

http://www.meanwell.com/search/LDD-L/LDD-L-spec.pdf

 

The only downside is that they fail high. If you looks your signal from the Ardunio (during programming for example) the input will float and the LEDs go to full brightness. You can overcome this problem by having a relay that is normally open to switch off your main power. Have this output go high while the processor is running.

 

These are super easy to use with any microprocessor.

 

I was looking at that touch screen for use on my project. Nice to see others using it. I wish it communicated via I2C or SPI though. :/

[phild3791]

Thanks Jedi/bhazard

I am building a Jarduino controller and i am having a difficult time choosing a driver with a 5v pwm option. This just might be the trick.

[evilc66]

Haven't been posting much around here of late, but just saw this.

 

These drivers are fantastic. Super cheap, and easy to use. I've been using a variety of them in various projects of late, and it doesn't get much better for DC drivers. They dim smoothly, and have a pretty fast reaction rate, so they can be used in storm simulations if you like that kind of thing.

 

For those looking to use these, mount them to a circuit board in some way. Either solder them directly, or use small pin SIP/DIP header sockets (not the same as standard 0.1" pitch headers, they have a smaller ID on the socket) if you want them removable. The pins are too small and fragile to attach wire directly to them. Just ask anyone that has broken the pins off the pot that comes with the Buckpucks (same size pin).

 

I wouldn't worry too much about the fail high situation with these. At least you don't have to apply power to make the thing work like the ELN drivers. This way you can make a simple fixed output setup with minimal fuss, and then have the option of adding a controller later. If you don't want the drivers to go to full brightness during programming of a micro (Arduino or otherwise), just add a pull down resistor to the PWM input of the driver. That will pull the input to ground (0% output) while the pin on the micro floats. Something around 10K ohm should do it.

[Cintax]

I am coming from a build using ELN-60-48P and these are the superior option. I am using the LDD-H with a a 48V power supply because of the string length (3x12 + TV,DR,CB). If I was going to do this again, I would go with the physically smaller LDD-L series and a lower voltage power supply. I'd have to use more drivers and break it down into smaller strings but the drivers are so much smaller physically and it would be a similar cost for the drivers (LDD-H x2 @ $13 and LDD-L x3 @ $9).

 

I can't believe I didn't consider a pull down resistor! I'll add those next time I have the controller board out.

 

My controller has five channels controlling six drivers. I decided to use the same PWM signal to control both of my royal blue strings. This leaves one PWM channel spare for future or to control a fan.

[bhazard]

The -HW versions with the wires pre-attached are out of stock everywhere, and won't be available for another 6-12 weeks. I'm gonna have to attempt to solder on some of them that I bought.

 

Do you have a link to a small board or easy setup I could use?

[Cintax]

I buy mine at Sayal but if you are ordering from Mouser they sell prototype boards.

[evilc66]

The -HW versions with the wires pre-attached are out of stock everywhere, and won't be available for another 6-12 weeks. I'm gonna have to attempt to solder on some of them that I bought.

 

Do you have a link to a small board or easy setup I could use?

 

If you need one quick, Radioshack has a number of pcbs that will work for prototyping.

[bored4]

I just picked up 3 of these smaller versions, omg only as big as my thumb nail. So tiny!

[bhazard]

These drivers, an external power supply, and an arduino type dimming controller is the most efficient and best dimming option for DIY leds by far.

[bored4]

If you don't want the drivers to go to full brightness during programming of a micro (Arduino or otherwise), just add a pull down resistor to the PWM input of the driver. That will pull the input to ground (0% output) while the pin on the micro floats. Something around 10K ohm should do it.

 

I'm still very new to all this electrical stuff and understanding how it all works. Could someone please put up a simple schematic for the pull down resistor connected to pwm channel ?

[evilc66]

You literally put a resistor between the pwm line and ground. If that doesn't make sense, Google.

[Cintax]

Use something with a high resistance like 10kOhm.

 

In the cicuit below you have a 1kOhm current limiting resistor to protect the Arduino GPIO and a 10kOhm pulldown to ground. Use a high value resistor for the pulldown since the circuit below is a voltage divider.

 

Vout = Vin(R2 / (R1 + R2)) = 5Vdc (10k / (10k + 1k)) = 4.54Vdc

 

Assuming a 5Vdc PWM signal and nominal resistance value you will get approximately 4.5Vdc at the PWM input and since anything between 2.5Vdc and 6Vdc is considered a high to the LDD-H this will be fine.

 

A larger value for R2 will get you less voltage drop.

 

Vout = Vin(R2 / (R1 + R2)) = 5Vdc (100k / (100k + 1k)) = 4.95Vdc

 

			 R1GPIO ------/\/\/\---------- LDD-H PWM Pin		   1kOhm	|					|	R2					|--/\/\/\-- GND					   10kOhm

[bored4]

I've looked at radio shack and all the resistor have a watt rating as well, 10kohm 1/2-1/4-1/8watt. Does that part matter?