An idea in an earlier blog is to make a pwm interface that can accept 5, 12 and 24V pulse streams. That one uses a bunch of resistors and has three separate inputs. Below that, wise commenter DB ...

Controlling LEDs is really quite simple. As you know, they need to be current limited which is as easy as applying Ohm’s law to your given set of values. To make things even more even there’s a slew ...