Not only various storage devices and input-output devices can be connected to USB ports. Very often it is used to connect devices that only power from it. Low-power light sources occupy a significant share among them.
Instructions
Step 1
Find any optical USB mouse that is mechanically damaged. If the mouse is faulty, but has no mechanical damage, it is better not to spoil it, but to repair it.
Step 2
Cut the cord from the manipulator. The device itself can later be used as a source of spare parts to restore the performance of other mice.
Step 3
Strip all four wires from the end of the cord. Place them in such a way that under no circumstances can they close either to the cable shield or to each other.
Step 4
Do not connect the cable to the USB port of your computer yet. Instead, use a dedicated charger that has such a port right on the case. Unlike a computer, it usually has short circuit protection.
Step 5
Having connected the cord to such a charger, using a multimeter operating in the DC voltmeter mode, at the limit of 20 V, find between which of the wires a voltage of 5 volts is acting. Insulate the ends of the remaining wires carefully.
Step 6
Take no more than ten super-bright white LEDs. In series with each of them, turn on a 200 Ohm resistor and a power of 0.5 W. Connect all strings in parallel, observing polarity. Apply power to them, also observing the polarity, through a 0.25 A fuse.
Step 7
Apply insulation wherever you need it. Place the assembled illuminator in any suitable dielectric enclosure. Show your imagination - as such a case, you can even use a plastic toy that your children are tired of, but which, in your opinion, will look beautiful on your monitor.
Step 8
Connect the finished structure to your computer. It will turn on and off simultaneously with the computer. When the computer is turned off, it can be powered by the charger mentioned above. Also, in some machines, power is supplied to the USB ports even in standby mode.
