I want to power a laser from an Arduino, and have a connection between a phototransistor. A easy connection seems to me a audio cable with a jack plug. Is this possible? Power consumption of the laser is 10mA@5V. Setup is a Arduino and 2 long easy to connect/ disconnect cables with laser on 1 and phototransistor on the other.
Yes it will work. 5V 10mA is 50mW, and pretty much any off the wall audio cable can carry that. Keep in mind that TS, TRS, and TRRS plugs and jacks are not designed for carrying power. When you plug the cable in, the tip will make a connection on each jack conductor, and that the conductors can short to each other. If you do want to use it, it's recommended that power be off before plugging it in or out.