SMD LEDs, EL Wire & LilyPads

Ok I went crazy with a little arduino shopping and bought 3 products Im trying to figure out:

  1. SMD Led strips.

  2. EL Wire

  3. Lilypads

Of these, I understand Im sorta SOL with the SMDs because I just began learning to solder and I dont even have a magnifying glass or such a small tipped soldering iron. Id like to know of a good SMD LED strip soldering though.

The EL Wire I just ordered the inverter from the place I bought them from.

The lilypads are the ones I think I can get away with for now. Can I just solder a + and - onto the ends of the pads and go with that? Know of any good tutorials for this?


Hi and welcome.

First lesson: ask advice here before you buy!

Do you have a usb uart/ttl-adaptor? You will need one to upload your sketches to the lillypad.

How will you power the circuit?

Do you have series resistors for those leds?

Do you have a breadboard for making your prototype on before you solder everything up?

Most importantly: what do you want to do with all this stuff?


Hi Paul, thanks.

  1. I don't have a lilypad controller. I just bought some lilypad Leds. I actually ended up connecting some wires to the ends of the led and presto, it worked. Each lilypad led has its resistor on the little board.

  2. I admit thought about the power sourcr until now :slight_smile:

  3. Now I realized I will need some sort of cr2032 cradle to power the Leds. So I have to find a microusb battery pack.

  4. I do have a breadboard.

  5. It's no biggie. My son wanted to add some stars to a science project he made and I just needed a small sketch to make the stars twinkle. I'm thinking of using a few maybe 8 Leds.

So my issue now becomes how to power the micro with Leds from a mobile power source. I'll need a microusb ported cr2032 battery pack. I think I can make one, I would need to know which are the power wires on a microusb cable.

I'm just waking up so I'll do some googling around.

I’ll need a microusb ported cr2032 battery pack.

A what? A cr2032 cell holds very little. How small does this whole thing need to be? Would 3 x AA or AAA cells be small enough? If not, you can get a variety of small rechargeable packs these days, designed for quadcopters & the like.

So were talking 190mAh of storage in a cr2032. A lily led according to the specs of the seller pulls 100mA peak, 30mA continuous.

So does this mean that I could "theoretically" operate 1 led for 190/30 = 6.3 hours?


190 mAh = 11,400 ma-minutes. So I could operate 10 leds for 11,400/30 = 380 minutes? Or 20 for 190 mins?

Hmm.. well, see how you go I suppose. What Arduino will you use? An Uno is likely to use 30~50mA.


Or 20 for 190 mins?

I think you need to rethink your maths…

20 leds, each drawing 30mA? That’s 600mA. Your 190mAh pack would last less than 19 minutes even if it were perfect, which it isn’t.

Yeah sorry, it would be:

1 led for 380 minutes
10 Leds 38 minutes
20 Leds 19 minutes

I know it's not perfect. I just need my son to run it for about 5 minutes while he presents it.

Lilypad designs are expected to be operated from a small LiPo - or if space permits, a 3 by AAA cell holder.