November 2007

Rev 1

1/22

AN2653

Application note

Operational amplifier stability compensation methods

for capacitive loading applied to TS507

Introduction

Who has never experienced oscillations issues when using an operational amplifier? Op-

amps are often used in a simple voltage follower configuration. However, this is not the best

configuration in terms of capacitive loading and potential risk of oscillations.

Capacitive loads have a big impact on the stability of operational amplifier-based

applications. Several compensation methods exist to stabilize a standard op-amp. This

application note describes the most common ones, which can be used in most cases.

The general theory of each compensation method is explained, and based on this, specific

data is provided for the TS507. The TS507 is a high precision rail-to-rail amplifier, with very

low input offset voltage, and a 1.9 MHz gain bandwidth product, which is available in

SOT23-5 and SO-8 packages.

This document simplifies the task of designing an application that includes the TS507. It

spares you the time-consuming effort of trying numerous combinations on bench, and it is

also much more accurate than using Spice models which are not designed to study system

stability, even though they can give a general trend.

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