CHAPTER 1 Models for Integrated-Circuit Active Devices 1 1.1 Introduction 1 1.2 Depletion Region of a pn Junction 1 1.2.1 Depletion-RegionCapacitance 5 1.2.2 Junction Breakdown 6 1.3 Large-Signal Behavior of Bipolar Transistors 8 1.3.1 Large-Signal Models in the Forward-Active Region 9 1.3.2 Effects of Collector Voltage on Large-Signal Characteristics in the Forward-Active Region 14 1.3.3 Saturation and Inverse Active Regions 16 1.3.4 Transistor Breakdown Voltages 20 1.3.5 Dependence of Transistor Current Gain/3r on Operating Conditions 23 1.4 Small-Signal Models of Bipolar Transistors 26 1.4.1 Transconductance 27 1.4.2 Base-ChargingCapacitance 28 1.4.3 Input Resistance 29 1.4.4 Output Resistance 29 1.4.5 Basic Small-Signal Model of the Bipolar Transistor 30