what are the calculation that LTspice does in background during noise analysis?
I am wondering about this issue because, I am not sure if the results I found out on my simulation are correct or not. In two points of my circuit I have the following noise density
which are very similar, then I use a BV generator to calculate the difference between the voltage at these two nodes and the result is the following:
How this result is calculated? I am not expecting to see that the noise becomes smaller, because the noise density sum as square at each frequency.
so why the total noise is smaller