Hi all, I'm designing a Power Distribution and Controller PCB for a Clock/LED Display frame and I'm looking for some guidance on the best combination of power supply and PCB layout. I've designed a PCB with 21 WS2815 LEDs and will have a 3D printed frame panel that will hold the boards in the number configuration you see in the attached pics. I plan on selling this as a product and hopefully manufacturing many, so total cost matters.

My plan was to have a barrel connector and place the PCB at the edge of the frame allowing a power supply brick to be connected similar to a laptop charger. There are a total of 630 LEDs and I split the layout into 5 strings of 126 LEDs, shown in different colors, each string will get their own power injection from the PCB. The board will also have an ESP32 which I will use to control the LEDs.

I'm a bit new to PCB and product design, and I'm not sure what is the best combination between power supply and PCB layout. WS2815 operate at 12V and I found this article that claims they consume 60mA at max brightness. Having a 450W power supply for a product like this sounds insane though, so I'm ok with LEDs not reaching max brightness. I think it's important to note that the clock display wouldn't have all LEDs on at the same time, but other full display patterns will.

• I did some research online and found that some gaming laptops have 150w and 200w power supplies, is it common for lighting products with a lot of LEDs to also have such high wattage power supplies?
• Is it more cost effective to buy a unique power supply that outputs 12V at high currents and keep the PCB layout simple, or have a more standard high voltage power supply with buck converters on the PCB?
• Should all 5 branches draw form one 12V high Amp source or have their own regulators with capped currents?
• Are there any safety regulations or design requirements I should be considering for a product like this?

 

The number of LEDs per segment seems like massive overkill in terms of brightness, and power consumption.
I would space them out more, create a gap between the LED and the diffusion surface.

The project becomes simple if you just use a single 12V power unit, with heavy connections to the power and ground.
Tie the power in at multiple points along the line, keep the voltage drops to the minimum.

You can run the LED's at a fraction of the rated current level, keep the max power low.

Nobody needs a 200 Watt LED clock, unless the digits are 3 feet tall? You do not specify.

 

The number of LEDs per segment seems like massive overkill in terms of brightness, and power consumption.
I would space them out more, create a gap between the LED and the diffusion surface.

The project becomes simple if you just use a single 12V power unit, with heavy connections to the power and ground.
Tie the power in at multiple points along the line, keep the voltage drops to the minimum.

You can run the LED's at a fraction of the rated current level, keep the max power low.

Nobody needs a 200 Watt LED clock, unless the digits are 3 feet tall? You do not specify.

Each LED PCB is 6" in length with 21 LEDs, the size of the frame is about 18" x 44". The clock is just one of the features and how the LEDs PCBs are arranged, the main purpose is to be an interactive light display. I already have one commissioned for a small business I'm working with, I have a prototype and now I'm trying to figure out how to optimize the design it in a cheap and effective way. I've been powering the prototype with a 24V/5A power supply, but it was just what I could find on amazon that made sense.

The looks and size of the product have already been agreed with the buyer so I can't change that right now. If you DID have to go with this number of LEDs, how high would you go on the wattage of the power supply?

 

Each LED PCB is 6" in length with 21 LEDs, the size of the frame is about 18" x 44". The clock is just one of the features and how the LEDs PCBs are arranged, the main purpose is to be an interactive light display. I already have one commissioned for a small business I'm working with, I have a prototype and now I'm trying to figure out how to optimize the design it in a cheap and effective way. I've been powering the prototype with a 24V/5A power supply, but it was just what I could find on amazon that made sense.

The looks and size of the product have already been agreed with the buyer so I can't change that right now. If you DID have to go with this number of LEDs, how high would you go on the wattage of the power supply?

20% more than the maximum load, minimum.

 

OK, an interesting challenge here. 21 LEDs in each segment. WHAT is going to be switching the segments on and off??
My choice would be to put all 21 LEDs for a segment in series, and then the supply current will be quite low so that thin wire can be used along with low current switching.
Of course, that is a guess on my part that the individual segments are going to be controlled to make it display digits.
We were never told what the purpose or intent is for the whole thing.
SO PLEASE clarify what the whole thing is supposed to do. Is it a light to illuminate the area or is it a digital display to show information???