LED "Name" Switch Toy for Toddler





Introduction: LED "Name" Switch Toy for Toddler

I made this toy a couple years ago when my son was 2. He's always been fascinated with lights and switches. In an effort to keep him entertained and perhaps learn the letters in his name, I built this simple toy. 

Used Parts
- about 50 LEDs (RED, Orange, Green)
- LM7812 Voltage Regulator
- Power source (I had an extra 15v wall wart in my junk bin)
- Power jack (N-size, radioshack)
- Wire
- Scrap wood (Oak)
- Various switches (I had laying around, you can find good deals on ebay)

Step 1: Create Template

My first step was to create a template to work from to aid in drilling the holes for the LEDs. I'm a hack with photoshop but was able to come up with something simple to use as a guide when drilling the holes to accept LEDs.

Step 2: Drilling Pattern

Next, using a drill press with the paper template taped onto the wood, I started drilling. I just lined up the bit with the crosshairs on the template. After the holes were drilled, I noticed that the letters were closer than I wanted relative to one another. Not a huge screw-up though as each letter has a different color so that contrast helps.

Step 3: Planning Circuit (schematic)

It was really important to prototype each letter on a solderless breadboard as each color of LED has a different desired forward voltage. Check the datasheet from the manufacturer to find out the FV. I bought a whole bunch of LEDs some time ago on ebay and didn't have any technical information on them but with some trial and error, I found the right values. Using OHMs law (I = V/R) got me close. However, I found that I had to play around a bit with the resistor values in order to get the letters to match in apparent brightness to one another. 

Before soldering, I drew up a schematic by hand but have since updated so it is legible. I'm using a LM7812 voltage regulator to get a nice steady voltage of 12v. I found a random 15v wall wart sitting in my parts bin that I'm using for a power supply.

Step 4: Solder the LED's and Switches

Next, I installed the switches, LEDs and soldered it all together. If you're new to this sort of thing, just go slow, take your time and do each segment, one at a time. As a whole, it looks like a complicated mess but as you're building it, it isn't that bad. For many electronics folks, this circuit is a walk in the park. 

Before installing the LEDs, I had checked each segment to ensure the LEDs were all working. The holes drilled in the front panel are to accept a 5mm LED. I used a dab of super glue on the side of each to keep them in place. 

As for mounting the LM7812, I could have (perhaps should have) mounted it against the interior wall. I used some heat shrink tubing to insulate it and it just hangs in there. A bit lazy, i guess. If you're going to be stepping down a high voltage, be sure you have a decent heat sink on your voltage regulator. Wrapping it also greatly minimizes its ability to dissipate heat. My setup produces very little heat so no worries but still, don't follow exactly what I did but rather mount it the "right way". :-)

Step 5: Put It All Together

When I made this a couple years ago, I didn't plan on putting it on Instructables so I didn't take as many pictures as I should have. Specifically, no pictures of making the cabinet. Sorry about that. Basically, just some oak I got from the hardware store, measured, cut, and glued together.

One note, I did use a Forstner bit to counter sink some holes for the back panel and to allow a couple switches and power jack to fit. The wood I used was a bit too thick for a few components. Depending on what materials you use, you may or may not need to worry about that. 

Anyway, that's it! If your child enjoys this half as much as my son, it will be well worth your time. :-)

2 People Made This Project!


  • Oil Contest

    Oil Contest
  • Water Contest

    Water Contest
  • Clocks Contest

    Clocks Contest

27 Discussions

Hey, I've got about a week until my boyfriends nephews birthday. This would be awesome but I am a DIY novice. I have no clue what half of the items you have mentioned are. Help?? Links to them?? Please please please? :)

1 reply

Help me help you. Which items are you needing help with? I'll do the best I can!

Nice work! Your instructable really stuck out to me because my name's Elliot and I've been looking for a fun father/son project to make for my 2 yr old. As a kid I always had a hard time finding anything with my name on it, and my son's name isn't going to be any easier i assume. Great work, great name! My son Ember and l will most definitely incorporate this into our Father's Day Toy Build, thanks for sharing!

1 reply

Thanks for the comment. Hope your build goes well and Ember enjoys it for a good long while. My son is 6.5 now and no longer plays with his!

I've finally finished my version of the sign for my nephew. Instead of batteries, I used a wall wart, which produced enough voltage and amperage to power all of the lights easily, so I bypassed the voltage regulator altogether. I also found that the wood used was too thick and for all of you looking to complete a similar project I would select 1/4" ply or similar. I used 1x8 cherry and ended up spending a lot of quality time with the forsner bits on the drill press. I also purchased chromed sleeves for the LED's from Ebay, and while they look nice, I wouldn't do it again, I just found that they added time, cost and unnecessary complexity. I did find that once I completed the sign that a couple of letters seemed brighter than others (specifically, Blue and Green), so playing with the resistors helped in balancing out the look. My wood working was not as precise as I would like as I rushed that part looking to get into the electronics and soldering where I am teaching myself some new skills to move on to more complex projects.


I loved this project and used it as my first real electronics project. Thanks for a great idea!

I made mine using 6V from 4AA. The LEDs I bought were very bright and I didn't want to blind the little guy, so in order to dim them I put higher resistance on each series of LEDs than Ohm's law would dictate. In case of the green I used no resistance because the voltage drop and inherent resistance across 3 of them dimmed them to the level I wanted. 6V meant a LOT more soldering but I wanted the box to be portable.

4 replies

I know you have just finished the project, but do you have any idea how long the batteries last? I want a portable one too, and as long as they last for several hours, I think I would likely follow your lead on using a battery setup

Excellent. I'm happy others found this a worthwhile project. Hope Cooper has a great time with it. :-)

Creative. it is cute.
is it just me but all toddlers are named Elliot? :D it is not the first nor the third instructable dedicated to a toddler Elliot.
hope he liked it! :)

If you can help...

I'm building a similar project for my son to play with. Mine uses 3 LEDs (Red, White and Blue) and 3 switches. Each switch is supposed to turn on one light, and they are supposed to each work independently, but run off of the same power source (9v battery, likely). I can't seem to get the wiring right, and I was wondering if you could help. The LEDs I'm using are these:
I need to know how to wire them to make them work independently with their respective switches and what value resistors to use (and where to put them for that matter). The total voltage requirement for all 3 on at once should be about 8-8.5v, so a 9v battery should work. I'm not worried about changing it out when it's dead, I just want this to work! I'm usually pretty good with electronics, but this one is driving me nuts! Thanks in advance for any help...

7 replies

There are some handy LED/Resistor calculators online, just google "LED Resistor calculator". Using one, I've determined that you'll want 3, 330 ohm, 1/4 watt resistors. Attached is a schematic as best as I can tell from your description.

Good luck and have fun! :-)

Screen Shot 2012-06-25 at 4.16.06 PM.png

Thank you so much for your time...my only question is that wouldn't the resistor values have to be different since the FV on each LED is different? I couldn't find a resistor calculator that let you put in more than one LED voltage, so I wasn't sure if this would work. I'll give it a shot though and let you know how it goes!

Thanks again for your help...It works! Not shown: I had to cut out a piece of old sponge and glue it to the back plate to hold the 9v in place so it doesn't rattle around, but here's some (sideways?) photos. Oh, and the boy loves it too!

photo 5.JPGphoto 3.JPGphoto 1.JPG

Love it. It's a lot like the first one I built. Watch out though, if your boy is like mine, he'll grow tired of it and then you'll be making another one more complicated. ;-)

After I built the one spelling his name and he got tired of it, I just broke down and bought him a set of "snap circuits". He LOVES them. Cheers!

Yes, you'd think they'd need to be different, I'm not entirely sure why! Play around with some values in that 200-400 ohm range and see what they LEDs look like. I did fiddle with values a bit on mine so they different colors would be close to the same brightness.

PS - what do you use to make your schematic drawings? Is that a dedicated program or do you just use an image editor like Photoshop?

I use a program called iCircuit (for Mac OS and iOS). Very simple and doesn't do as much as others but for someone at my skill level, it is perfect.

Hi, I love this and I have ordered the led's for the project. My little guy is so busy and mobile it would be convienant to have batteries for this project, but drawing ~1 amp, how long would a set of batteries last? I was also thinking I could do it with the option for batteries or a wall wart. Any thoughts?