I have a very newbie and possibly stupid question, but I have been searching many sites and just can't find an answer.
Imagine you have a circuit, some device (electro-motor) that is powered with for example 20V dc power supply. Then you have another TTL circuit.
I am able to programatically change the output on TTL circuit to 0 (0,8V) or 1 (5V), but what I need to do is control the second circuit, using this digital output, that means, for example if I send 1 to output, the 20V device is switched on, when I send 0, it's turned off.
What is a simplest way to achieve this?