I am trying to understand Type1, 2 and 3 opamp compensators used in DCDC converters. Type 1 is just an opamp integrator. Type 2 has a C in feedback loop with parallel RC. How does this boost the phase Margin? (page 307 - http://tinyurl.com/3qyt5dc) I understand phase and gain margin when I look at the bode plots. But I don't get it when I am designing a ckt. Also, how do I relate phase shift with phase margin. For example, the inverting integrator output has -180 phase shift, but phase margin is -90 degrees. Is there a way to relate the two?