LED Clothing Project

Hello Arduino Experts,

I am new to this realm, and I am working on a LED Clothing Project. I was wondering if you could provide some insight on a few questions for me.

I am trying to connect 10 LED strips (hyperlinked to product) together. Each LED strip will be have approximately 30 LED RGB lights, with each of the three colors maxing out at 20ma at full brightness, for a maximum total of 60ma (hyperlinked to specification) per light. I am wanting to create a portable “matrix” display (example shown) shirt with these LED strips, and I am trying to figure out the best way to design and power the circuit.

For the design, I am guessing I will need an Arduino Mega (linked) so that I can individually program all 300 lights? (Please confirm if this is the best option). For the circuit design, should I connect these strips to the power source in series, or in parallel? Do I have to worry about voltage drop, or additional resistors? I have taken some electrical engineering courses, but not enough to feel confident on the proper design for my project.

For the power source, since this is portable, I am wanting the display to last for about 5+ hours, if possible. Although the maximum draw is 60mA x 300 bulbs = 18000mA, I will realistically only have on a small number of these (in patterns) at less than full brightness. Let’s assume on average that half the lights are on and they are running at 25mA, so I will have an average draw of 20mA x 150 bulbs = 3000mA.

For my power source, what should I choose? The Mega requires 12V, but the LED lights require 5V. Do I have to use two separate power sources? Can I use a 15,000mAh 5V 2.1A/1.5A (example) battery pack? Or do I need to go with something like this 18,000mAh 12V 6A (example)? Would the 12V fry the LED strip?

For the programming, I have not programmed with Arduino before (I do have some other programming experience). Do the standard Arduino libraries work for any set of LED lights (in particular, the one I referenced above) or do I need to get specific libraries from the manufacturer for a specific brand of lights?

From a “portability” standpoint, how does the programming work? If I program from the computer, will the Mega “remember” the program and apply it to the lights once I attach the battery? Or is there a way to put a file on a flash drive and program it remotely?

Any help you can provide would be greatly appreciated. Thank you.

crfangmann: For the design, I am guessing I will need an Arduino Mega (linked) so that I can individually program all 300 lights? (Please confirm if this is the best option).

A Pro Mini would probably do, the only reason for using a Mega would be if you need to do really complex patterns.

crfangmann: For the circuit design, should I connect these strips to the power source in series, or in parallel?

The power connections must be in parallel, the data connections can either chain from strip to strip, or perhaps be divided into 4 or so from separate pins.

crfangmann: Do I have to worry about voltage drop, or additional resistors?

Voltage drop - you sure do have to worry about it, which is why the power connections must be in parallel. Resistors lose power - why would you want to use them?

crfangmann: Although the maximum draw is 60mA x 300 bulbs = 18000mA,

That is correctly called 18 Amps.

crfangmann: Let's assume on average that half the lights are on and they are running at 25mA, so I will have an average draw of 20mA x 150 bulbs = 3000mA.

That is called three Amps.

crfangmann: The Mega requires 12V,

It most surely does not!

crfangmann: Do I have to use two separate power sources?

Yes and no.

crfangmann: Can I use a 15,000mAh 5V 2.1A/1.5A (example) battery pack?

You need regulated 5V.

crfangmann: Or do I need to go with something like this 18,000mAh 12V 6A (example)?

That would be about right.

crfangmann: Would the 12V fry the LED strip?

It would if you were silly enough to connect it.

You need to use the 12V battery pack, and provide two switchmode converters, which are efficient, one to power the LED strips, and one to power the Pro Mini at 5V.

crfangmann: For the programming, I have not programmed with Arduino before (I do have some other programming experience). Do the standard Arduino libraries work for any set of LED lights?

Yes.

crfangmann: From a "portability" standpoint, how does the programming work? If I program from the computer, will the Mega "remember" the program and apply it to the lights once I attach the battery?

That is the whole purpose of it.