PWM LED drivers

Greetings!

I have been looking into using an Arduino Uno Rev3 to supply supply a PWM signal to 3, possibly 4 LED drivers.
The research I’ve done indicates that most Arduino clocks run under 1khz, however the drivers are suggested to receive a signal between 1khz and 10khz.

I uncovered an old thread using the same MeanWell drivers I am that had some bad advice (according to the drivers documents) regarding grounding the PWM circuit. That thread did indicate that the frequency can be manipulated using code, but given that the person seeking help kept burning out pins after following the advice given, and the thread came to a dead end, I’m not sure what to believe.

Some information on the project;
1 * MeanWell LRS-350-12
3 * MeanWell LDH-45A-1050W
1 * MeanWell LDH-45A-700W (if I use UV)
8 * Cree XLamp XT-E 3000K
4 * Cree XLamp XT-E 6500K
14 * Cree XLamp XP-E Photo Red
4 * Cree XLamp XP-E2 Red (625nm)
3 * Cree XLamp XP-E2 Blue (470nm)
3 * Cree XLamp XT-E Royal-Blue (450nm)
2 * UV 410-420nm
2 * UV 400-410nm
2 * UV 385nm
2 * UV 365nm
12" Makers LED heatsink (original)

Will an Arduino Uno be up to this task alone?
Can I reliably change the clock speed with code?
Is there a better way to change the frequency?
Would a DC motor shield be of any use?

http://www.meanwellusa.com/webapp/product/search.aspx?prod=LDH-45(DA)#1

Screenshot_20200112-015246.png

Cannaking85:
I uncovered an old thread using the same MeanWell drivers I am that had some bad advice (according to the drivers documents) regarding grounding the PWM circuit.

And this thread is where?

The problem is that the PWM control input is (presumably) not isolated from the rest of the circuit.

Cannaking85:
Will an Arduino UNO be up to this task alone?

Maybe. I am not familiar with how many PWMs you can use simultaneously and at what frequencies.

Cannaking85:
Can I reliably change the clock speed with code?

That is the usual way. Actually, the only way. :cold_sweat:

Cannaking85:
Is there a better way to change the frequency?

No. Can't do it with a a screwdriver. :roll_eyes:

Cannaking85:
Would a DC motor shield be of any use?

Only if you are matching it with a motor. :astonished:

My apologies, I should have indicated right at the start that I discovered Arduino and the like about 3 weeks ago. So I appreciate some patience. I'm unfamiliar with its capabilities, however, electricity and I have a 30 year relationship.

All I would like to accomplish is to have different spectrums come on at different times, utilizing the same clock. (Without burning my house down) I'll probably just use the available relays, if I even use this platform.

Through the sarcasm I did manage to get some information, for that, I thank you Paul.

Here is a link to the previously mentioned thread.

Cheers,
Vern.

What made you select the LDH-45 over the more commonly used LDD-xxx.

Is a lower PWM frequency a problem for your project.

What is your exact LED configuration (Vf of the LEDs and number of LEDs in a string).
Leo..

Wawa:
What made you select the LDH-45 over the more commonly used LDD-xxx.

Is a lower PWM frequency a problem for your project.

What is your exact LED configuration (Vf of the LEDs and number of LEDs in a string).
Leo…

Hello Wawa,

The LDH-45 were the available MeanWell boost drivers available where I was shopping.

The data sheet for the driver indicates the PWM signal should be between 1khz and 10khz, I’m not sure if that is a problem or not, but it seems to me like it might be.

First driver 1050mA;
14 dark red - 2.5v each

Second driver 1050mA;
3 royal blue - 3.2v each
3 blue - 3.4v each
4 red - 2.65v each

Third driver 1050mA;
8 warm white - 3.2v each
4 cool white - 3.2v each.

Fourth driver 700mA;
2 UV 410-420nm - 3.8v each
2 UV 400-410nm - 3.8v each
2 UV 385nm - 3.8v each
2 UV 365nm - 3.8v each

I had been planning this light for quite some time before I even knew what an Arduino was, so if it seems like using one is an afterthought, it totally is.
My main reason for wanting separate schedules is to use the UV for only 2 or 3 hours per day. I could simply do this with 2 store bought timers, but where is the fun in that?

Thanks for reading,
Vern

No experience with that driver. PWM frequency only seems to affect linearity in the low-light region.

Don't know if you're expecting dimming to low light levels.
That might not be possible with higher PWM frequencies.
Can try PWM pin 5 and/or 6 (Uno). They default to 1kHz.
Leo..

Thank you Leo,

It appears that the driver has a broader range of brightness at 1kHz versus 10kHz, so pins 5 and 6 should be ideal. I wasn't sure if 980Hz was close enough, I do know in many industries its common practice to round up, but I didn't want to assume.
Like they say, a little bit of knowledge is a dangerous thing. So I try to gather as much as I can.

Cheers,
Vern