單端輸入差分放大電路輸入信號的等效變換

本文對單端輸入差分放大電路發(fā)射極耦合傳輸?shù)姆治龇椒ㄟM行了深入研究，利用電路分析的方法將單端輸入信號等效變換成差模輸入信號與共模輸入信號的疊加。指出等效變換并不需要發(fā)射極電阻R。很大的條件，R。的取值大小只反映對共模輸人信號的抑制程度。并把這種方法與輸人信號用數(shù)學方法等效變換進行了對比，得出這兩種輸入信號的等效變換方法具有等效性的結論。并介紹了單端輸入差分放大電路的教學處理方法。

Analysis methods of emitter coupling transmission in differential amplifier have been researched．Through circuit analysis，single end input signals have been converted to superposition of common—mode signals and difference-mode signals．Condition of big emit—port resistance R。is not necessary when perfclITn this equivalent transform．The value of R。only reflects the suppression degree of common—mode signals．
Compared with mathematical transformation methods of input signal，the conclusion that the two methods are equivalent has been drawn．At last，teaching processing methods of single-end input differential ampli—fier are introduced．