Discussion on Stability Engineering Criterion of Negative Feedback Amplifier Circuit

The stability criterion of amplifier circuit in analog circuit teaching, as a key knowledge point, is an important part of the knowledge system from "device to single-stage amplification (SSA) to multi-stage amplification (MSA) to integrated amplification to feedback". Most existing textbooks explain stability conditions based on the absence of self-excited oscillations, and the engineering criterion for the stability of negative feedback amplifier circuits is often presented without a thorough analysis of its conditions and applicability. This approach may lead to an inadequate understanding among students, hindering the development of skills that integrate engineering practice with theoretical knowledge. To address this issue, this paper first discusses the definition, analytical principles, and methods of stability in negative feedback amplification circuits. Subsequently, from the perspectives of "double-pole conditions" and "multi-pole conditions," it thoroughly analyzes and derives engineering criterion, and verifies its applicability. Introducing such applicability analysis effectively enhances students' understanding of the stability of negative feedback amplification circuits, which holds significant educational value.