5.0 Introduction 5.1 Device Structure and Physical Operation 5.2 Current-Voltage Characteristics 5.3 The BJT as an Amplifier and as a Switch 5.4 BJT Circuits at DC 5.5 Biasing in BJT Amplifier Circuits 5.6 Small-Signal Operation and Models 5.7 Single-Stage BJT Amplifiers 5.8 The BJT Internal Capacitances and High-Frequency Model 5.9 Frequency Response of the Common-Emitter Amplifier 5.10 The Basic BJT Digital Logic Inverter 5.11 The SPICE BJT Model and Simulation Examples