While we wouldn’t want to document a computer motherboard with ASCII schematics, it’s great for a quick-and-dirty circuit diagrams. Not exactly schematics, but [Duckman] has some Arduino ...

Once you’re in, you are free to upload your Eagle or KiCAD circuit diagrams, which are then run ... the ability to zoom in on any portion of the drawing to see the circuit’s finer details.

Here is an Arduino based circuit with three independent pulse width modulated (PWM) channels to fulfil your requirements! Just follow the schematic diagram to complete the construction, and use any ...