全新的虚短虚断概念与两类集成运放之导出

New concept of virtual short circuit and virtual open circuit and derivation of two types of integrated operational amplifier

自有集成运放以来,虚短虚断、两类集成运放就应运而生,但它与典型的单级电流串联负反馈、电压并联负反馈;两级电压串联负反馈、电流并联负反馈有什么必然联系在国内外均少见详细报导.本文力图通过对这4个电路中反馈元件的双向等效折合,再准确计算ib、ube、Auf的数值,决定把ube和ib同时趋近于零定义为虚短虚断;而把计算A uf时,狠抓两个核心元件的主导作用,忽略工程上的次要部分,就得到了与两类集成运放相同的结果,这既避免了对原分离电路的繁琐而复杂的计算,也把从分离电路到集成运放实现了完美无缺的自然过渡.

Since we own integrated operational amplifier,virtual short circuit and virtual open circuit and two types of integrated operational amplifier have emerged,but it has no necessary connection with the typical single-stage current series negative feedback and voltage parallel negative feedback,the two-stage voltage series negative feedback and current parallel negative feedback,and it have no detailed report at home and abroad.In this paper,we try to accurate calculate i b、u be、A uf according to two-way equivalent conversion of the feedback elements in the four circuits.When u be and i b approaching to zero at the same time is defined as virtual short and virtual break.When calculating A uf,we should pay close attention to the two core components and ignore the secondary part of the project,and get the same result as the two types of integrated operational amplifier.In this way,not only the tedious and less used calculation of the original separation circuit is avoided,but also perfect transition from separation to integration is achieved.