RF IC设计理论及指南Sheet 1 of 1 Basic BJT Circuit Figure 1 below shows the simplied ‘Pi’ model of a BJT. B ib c b Vin Β.ib -gm.Vbe C Vout Zout Vout Rbe Vin = Vbe Vbe e Zin Rce E Figure 1 Transistor symbol and simplified ‘Pi’ model We can see that output consists of a current source ……