Switching Power Supplies A - Z

Chapter 7

The very use of the word “phase” in the previous paragraph implies we are talking of sine

waves once again. However, this turns out to be a valid assumption, because as we know,

arbitrary disturbances can be decomposed into a series of sine wave components of varying

frequencies. So the signal we “inject” (either on the bench, or on paper) can be a sine

wave of constant, but arbitrary amplitude. Then, by sweeping the frequency over a wide

range, we can look for frequency components (sine waves) that have the potential to lead

to instability — assuming we can have a disturbance that happens to contain that particular

frequency component.