Tech Olive

As much as anyone out there, I oh so very much *love* typing on ergonomic keyboards [/sarcasm]. So to save my fingers from the pain and endurance of a 1,000 word article, today’s is a bit quicker. But please do enjoy learning how to use LEDs in just about anything with a power source……

For me, I was always intrigued by how some mice had a glowing mouse wheel. It seemed so simple, yet I never actually found a moment where I could modify one of my older optical mice. The concept is easy enough, not even a circuit diagram is needed, and I can list out the parts now. You will need an LED (any color), a resistor (based on which LED you choose, use this calculator (thanks led.linear1.org!)), a switch or button (any kind), and some wire. All items can be picked up for less then 5$ at a local electronics shop. As for tools, pretty much a soldering iron.

Solder the resistor to the LED (doesnt matter which way), solder a wire to the other leg of the resistor, and another wire to the other leg of the LED. In my case, it was a blue LED (3V @ 20mA) and a 100ohm resistor (all I had on hand, the calculator may say 1ohm or something). Splice in the switch somewhere if you want to turn it off. My power supply is the two AA batteries inside the mouse. Technically you’re done! Super simple circuit right?

Now the fun part! Open up your mouse and locate some contacts you can connect the wires on from your resistor/LED combo, but don’t get it soldered on yet! LEDs only work one way, so just press the two wires, one to positive battery terminal inside the mouse, and the other to the negative battery terminal. If the LED doesn’t light up, take the wire you were pressing to positive, and put it onto negative, and take the wire that was on negative and place it on positive. This switches which way the LED is getting voltage. You should have a beautifully glowing creation in front of you. If not, check your solder job, and that your batteries are fully charged/have enough voltage to light your LED in the first place. (Example: A 3V battery will not light a 6V LED).

Opened up mouse. Battery terminals are labeled B+ and B- for me.

When you’re sure you have the LED’s orientation correct, solder it in. Using some hot glue, place the led inside the mouse somewhere, re-assemble your mouse and put in some batteries. You’re done! Feel free to add more LEDs or change position of the current one until it’s where you like it.

My switch/resistor/LED creation in position and hot glued.

Finished glowing mouse!