Pole-zero analysis of multi-stage amplifiers: A tutorial overview

Analyzing pole-zero locations of an amplifier is essential to 1) understand the characteristics of a circuit in the frequency domain, and 2) choose appropriate frequency compensation techniques to guarantee the stability of a circuit over a specified range of load resistance and capacitance. The objective of this paper is to provide tutorial treatment of the steps for analyzing poles and zeros in multi-stage amplifiers. These techniques can be equally applied for the analysis of power management circuits such as low-dropout voltage regulators (LDOs) and controllers for DC-DC converters.