(Another) DIY LED Controller - Simple Arduino Style

[Jeff D]

How many drivers can I put on 1 output? Do I have to run each driver on its own channel?? thanks , and good night! J

 

[katchupoy]

What happens is 1 channel (transistor) can handle many drivers. So 6 drivers in one transistor... and another 6 drivers for another transistor.

each transistor will have their schedule ramp up and down, thus you will only have two channel.

 

[katchupoy]

Here is a simple breadboard diagram.... for those people who havent use breadboard before... you will notice there are vertical dots and horizontal dots .... I added a note how they are link or connected together.

 

[TheReefNinja]

katchupoy awesome work. Great images even a monkey could assemble it.

Ok so I talked to Bill from reefledlights at my local swap and he does not recommend the PWM output and said idealy we should make a circuit to convert that to a analog 10v claiming that the constant on/off signal might lower the life significantly... which we already knew. I dont care as I only have 2 drivers and live 20 minutes from him if I ever need a replacement, but those with 6-7+ drivers that could be costly if it did happen. I have seen on the hydra project they made a ELN shield ( http://code.google.com/p/hydra-reef/source/browse/trunk/#trunk/hardware/ELN_shield ) that I am not sure if it just converts the PWM sig to 10v or converts it analog 10v might be worth looking into could be a simple circuit. I know your a newb too but I think we may be able to make a cheap simple circuit or one may exist to convert the pwm to a clean dc signal, at least then our signal going to the transistor will be a constant one. I will have a look on google in the morning to see what I can find on this.

Any chance you could post or pm me the code for the arduino so I can take a look how it all works. I picked up a few digital temp sensors for under $2 each and I want to look at how I will have to include one in my heat sink for led temp. I know how to wire the temp sensor already. I found a chunk of code to read it and wanted to see if it is easy to include.

I also need to look into getting this IR remote to work with it but thats for a later day.

 

[TheFishMan65]

The shield you are referring to is a 10 V PWM.

 

[LSUJosh]

Using a PWM to dim will not affect the LEDs life expectancy, these components are made with the capability of withstanding those quick changes as PWM is the optimum way of controlling strings of LEDs.

 

[TheFishMan65]

They are worried about burning out the ELN-XX-XXD driver. The Ds have an analog dimming signal and the ELN-XX-XXPs use a PWM singal.

 

[BINKSY1973]

Great project following with interest and easy to follow upto now.
Just one thing what powers up the Ardunio board and breadboard for the 5v?
Or have i missed something?

Cheers Gordon.

 

[katchupoy]

Great project following with interest and easy to follow upto now.
Just one thing what powers up the Ardunio board and breadboard for the 5v?
Or have i missed something?

Cheers Gordon.

.


Updated Parts List...


If you check the current checklist. There is this 6V power supply that will power the Arduino.

In reality, you can just use the same 10V power supply that you use to your LED drivers. This is my current setup right now.


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[BINKSY1973]

Sorry overlooked that in the parts list. Does the 5v supply connect to the breadboard or the power jack on the Adrunio?

Cheers Gordon.

 

[katchupoy]

your external power supply goes to the power jack. now the one that goes to the bread board comes from 5V of arduino...

 

[BINKSY1973]

Thanks for clearing that up. Makes perfect sense now.

Cheers Gordon.

 

[katchupoy]

The good thing with Arduino board, is that it can handle a wide range of volts thru power jack. Right now im using 10V thru power jack. And then arduino will regulate it down to 5V. Thats why you have 5V pins so you can tap power from here.

Unfortunately, the "amps" on the pins are not that great. We are just talking about "40 ma" at the most. Not even enough to power a servo (later on this project). But enough to control logic level power, example: IC, transistors and some very small relays.

 

[Molehs]

So if I'm getting a P series driver then my setup will be a little different but slightly simpler on the hardware side? And instead of a manual analog dimmer it would be done in the coding with buttons, yes?

 

[TheFishMan65]

I think so, but I haven't seen the code.

 

[BINKSY1973]

If im using an LED driver that can accept low frequency PWM signal would that mean i would not need the transistors and resistors? and connect directly to the PWM output on the Ardunio?

Cheers Gordon.

 

[TheFishMan65]

It depends on the voltage required by the PWM input of the driver. If the driver only takes 5 volts then yes it can drive it directly. If it takes more or less then you cannot.

Next question is how many drivers do you need to control with each PWM signal. The Arduino IIRC can supply 40 ma. If your driver needs more than that you can not drive it directly. If less than you can drive 40 divided by the current required. You must roung down. So if you need 21 ma you can only drive 1.

 

[BINKSY1973]

Thanks for your reply, sounds like it would be best to use transistors and resistors to be on the safe side.
Would be looking at 2 drivers per PWM signal usind a total of 6 drivers, so need 3 PWM outputs.

Cheers Gordon.

Cheers Gordon.

 

[terahz]

My guess would be that you will be able to power the 6 drives without problems. I'm currently driving 8 on 4 PWM pins without issues.

 

[katchupoy]

So if I'm getting a P series driver then my setup will be a little different but slightly simpler on the hardware side? And instead of a manual analog dimmer it would be done in the coding with buttons, yes?

On the hardware side, its basically the same. The only difference between the "P" and the "D" drivers are the codes used on the sketch.