All of them will be shown step by step. By H. Dean Venable, Venable Industries Measurement of loop gain and loop phase shift versus frequency is generally possible with single output power supplies or multiple output supplies where each output is independently regulated. These measurements are necessary to determine the phase and gain margins and insure stability of the feedback loop.
Measurement requires access to a point where the loop is confined to a single path.
Such a point does not exist in many low-cost computer power supplies, and these supplies constitute the numerical majority of power supplies manufactured today. This paper presents techniques for overcoming this obstacle and obtaining loop data even where a single signal path is not accessible.