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Design >> RF Design >> stability issue.....
https://designers-guide.org/forum/YaBB.pl?num=1288185023

Message started by saam on Oct 27^th, 2010, 6:10am

Title: stability issue.....
Post by saam on Oct 27^th, 2010, 6:10am

Capacitor C also serves for ensuring the stability of the circuit. Since the open-loop transfer function has two poles very close to each other, introducing a dominant pole at node 2 improves stability.
Can anyone explain why? (i am attaching the circuit)
Thank U
saam

Title: Re: stability issue.....
Post by jayce3390 on Dec 2^nd, 2010, 8:07am

This is real part of poles which is important, not the fact that they are close to each other...
You need poles with a negative real part to ensure stability.

Title: Re: stability issue.....
Post by Frank Wiedmann on Dec 3^rd, 2010, 12:58am

See http://web.engr.oregonstate.edu/~karti/ece422/lec11_16_10.pdf, especially the slides entitled "Adding a Dominant Pole".