Title :
Analysis and compensation of two-pole amplifiers with a pole-zero doublet
Author :
Palmisano, G. ; Palumbo, G.
Author_Institution :
Ist. di Elettrotecnica ed Elettronica, Catania Univ., Italy
fDate :
7/1/1999 12:00:00 AM
Abstract :
A simple representation of a two-pole amplifier with a pole-zero doublet is proposed which can be used in the compensation of transconductance amplifiers. The model is based on the consideration that a pole-zero doublet does not greatly modify the behavior of the closed-loop amplifier. Indeed, assuming an underdamped behavior we have found that the pole-zero doublet only affects the phase margin and, hence, it can accurately be accounted for by properly modifying the second pole of the original two-pole amplifier. Simulations on a two-stage transconductance amplifier show that such a model closely agrees with the time response of the real amplifier
Keywords :
analogue integrated circuits; compensation; differential amplifiers; feedback amplifiers; linear network analysis; poles and zeros; compensation; phase margin; pole-zero doublet; time response; transconductance amplifiers; two-pole amplifiers; Analog circuits; Analog integrated circuits; Circuit simulation; Differential amplifiers; Feedback amplifiers; Feedback circuits; Frequency; Time factors; Transconductance; Transfer functions;
Journal_Title :
Circuits and Systems I: Fundamental Theory and Applications, IEEE Transactions on