PNP三极管放大条件应满足VE>VB>VC且UEC>UCES。若图中三极管工作在放大状态,则:VE=6VVB=VE-0.7=5.3VVC=IbβRc=βRcVB/Rb<5.3VUEC=VE-VC=6-5.3βRc/Rb>0.7V6-5.3βRc/Rb>0.75.3βRc/Rb<5.3即: Rb>βRc