The chapter covers main characteristics of the devices used in power amplifiers (PAs) and provides basic knowledge about the specifications of these devices and the transistor models that are used in PA designs. The Preface covers the basic characteristics of main semiconductor device types used in PA designs. These devices have been in use for many decades, the technology of which is well established and its production is repeatable with high yield. Now, these devices show really impressive results. They work up to the terahertz region and can deliver kilowatts of power at low radio frequencies (RF). Probably one of the most promising devices now is the GaN high-electron-mobility transistor (HEMT), and they yield high-power and high-frequency results in number of applications. There are a plenty number of literature on these devices regarding how to design PA, and using these transistors has put a tremendous success in its field. A very small part of these references is listed here. The models come in small signal (SS), large signal (LS) categories, and for all these devices, extraction procedures, software is available.
Chapter Contents:
- 2.1 Introduction: active devices
- 2.1.1 Semiconductor devices for PAs
- 2.1.2 GaAs FET and InP HEMT devices
- 2.1.3 GaN HEMT devices
- 2.1.4 CMOS devices
- 2.1.5 HBT devices
- 2.1.5.1 Importance of correct derivatives
- 2.1.5.2 Model types
- 2.2 Sources of nonlinearity (Ids, various Gm, Rd, Rtherm, capacitances, breakdown)
- 2.3 Memory effects
- 2.4 Nonlinear characterization
- 2.4.1 Active load-pull
- 2.4.2 Fast active load-pull
- 2.4.3 Nonlinear characterization using active load-pull
- 2.5 Small/Large signal compact models
- 2.5.1 Small-signal equivalent circuit models
- 2.5.2 Large-signal compact models
- 2.5.3 FET ECLSM model
- 2.5.3.1 Ids equations
- 2.5.3.2 Gate current
- 2.5.3.3 Charge equations [54–60]
- 2.6 The large-signal model extraction
- 2.6.1 Extraction of on-resistance (Ron)
- 2.6.2 Igs parameter extraction and fit
- 2.6.3 Drain Ids current extraction and fit
- 2.6.3.1 Extraction fitting of λ
- 2.6.3.2 Ids = f(Vgs) parameter extraction FIT
- 2.6.4 Igs parameter extraction model fit low Vds
- 2.6.5 Self-heating modeling thermal resistance Rtherm fit
- 2.7 Large signal FET equivalent circuit
- 2.8 Capacitances and capacitance models' implementation in simulators
- 2.9 GaN implementation specifics
- 2.10 Implementation of complex Gm shape
- 2.11 Breakdown phenomena
- 2.12 Large-signal model evaluation: power-spectrum measurements and fit
- 2.13 LSVNA measurement and evaluation
- 2.14 Packaging effects
- 2.15 Self-heating modeling implementation GaN
- Appendix
- Acknowledgments
- References
Inspec keywords:
power HEMT;
semiconductor device models;
power transistors;
gallium compounds;
power amplifiers;
nitrogen;
radiofrequency amplifiers
Other keywords:
large signal categories;
PA designs;
high-power results;
main semiconductor device types;
terahertz region;
low radio frequencies;
transistor models;
GaN;
HEMT;
nonlinear active device modeling;
power amplifiers;
small signal categories;
extraction procedures;
high-frequency results;
GaN high-electron-mobility transistor
Subjects:
Semiconductor device modelling, equivalent circuits, design and testing;
Amplifiers;
Radio and television receivers;
Power semiconductor devices
