DIY LED: Kid’s headband

A headband with all the colors of the rainbow!

My kid thinks that her Mom is an inventor and an artist. She’s been trying out my LED wearables for a long time now, and it’s such a joy seeing her dance around with them. Today is her 6th birthday, so I spent yesterday evening making a slightly more complicated circuit than I use to.

For this project I use:
A cheap headband for kids
Digispark microcontroller (Arduino compatible)
LiPo (Lithium Polymer) battery
LiPo battery charger
WS2812B LED strip (18×2 pixels fit the headband well)
A 1k resistor
A male and a female connector
Normal cable

I started out with soldering the LiPo battery to the battery charger. Then I found a red female connector, and put it on the positive side of the battery. Because of this, the LED’s won’t blink when I charge the wearable overnight.

In contrast to most of my projects, this one has a small battery soldered in place. Usually I just go for powerbanks, because they are easy to handle, switchable, have lots of power and I don’t mind big bulky USB cables all over the place. However, for a six year old an external battery will be in the way.

From the left: battery, battery charger, female/male connector, microcontroler.

I then solder a male connector to 5V on the microcontroller, and GND to GND. From P0 I solder the 1k resistor, and then I glued these pieces to the headband. Usually I leave glueing for last, but in this case I don’t want excessive cable but want everything to be exact.

The resistor goes into DI (Digital In) on the LED strip, 5V to 5V and GND to GND. At this stage I also uploaded the code to the microcontroller, making sure that the LED strip lights up as it’s supposed to. Then I glued the LED strip in place, all but the last piece.

First LED strip in place!

The ends of the headband are quite narrow, so the easiest way to solder 5V in this case is to simply sandwich them together. Then I tried to make the other cables as short as possible, and solder on the backside if possible.

Sandwich the 5V connection, make the cables as short as possible and secure with hot glue.

Lastly I glued the last strip in place and put some extra glue on ends and soldering connections for extra structural integrity.

These are the schematics for the LED headband.

I hope this headband is strong and lightweight enough to not be in the way of wild games, and I hope my six-year-old will soon start collaborate with me on what to build next 🙂

Sparkling while charging <3