I'm having trouble analysing the voltages/currents in various logic circuits.
For example, I can't understand WHY a NOT circuit actually works.
I've watched a YouTube video from Ben Eater (link: https://www.youtube.com/watch?v=sTu3LwpF6XI @ time 2:30)
The circuits he presents there is attached here:
Why is it that when you press the switch, no current flows through the LED?
As far as I'm concerned, pressing the switch equals to creating a short between points A and B. So I could replace the transistor with a wire that connects to A and B.
I don't see how these prevents current from flowing through the LED.
Using the equations for parallel loads, some current still flows through the LED.
He also says that when you press the switch, it zeros the potential difference between points A and B. I can't see how this happens using the equations I have.
Can someone please help and clarify?