Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2012 Design of a Magnetically Tunable Low Noise Amplifier in 0.13 um CMOS Technology Jeremy Brown Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Electrical and Electronics Commons Recommended Citation Brown, Jeremy, "Design of a Magnetically Tunable Low Noise Amplifier in 0.13 um CMOS Technology" (2012). Graduate Theses and Dissertations. 12672. https://lib.dr.iastate.edu/etd/12672 This Thesis is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Design of a Magnetically Tunable Low Noise Amplifier in 0.13µm CMOS Technology By Jeremy L. Brown A thesis submitted to the graduate faculty in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Major: Electrical Engineering Program of Study Committee: Nathan Neihart, Major Professor Degang Chen Mani Mina Iowa State University Ames, Iowa 2012 Copyright © Jeremy L. Brown, 2012. All rights reserved. ii TABLE OF CONTENTS LIST OF FIGURES ................................................................................................................. iv ACKNOWLEDGEMENTS .................................................................................................... vii ABSTRACT ........................................................................................................................... viii CHAPTER 1. INTRODUCTION ........................................................................................... 1 CHAPTER 2. LITERATURE REVIEW ................................................................................ 4 2.1 Wideband LNAs .............................................................................................................. 4 2.1.1 LC Bandpass Filtering .............................................................................................. 5 2.1.2 Reactive Feedback .................................................................................................... 7 2.1.3 Resistive/Source Follower Feedback........................................................................ 8 2.1.4 Common Gate Input Stage ..................................................................................... 10 2.2 Multi-band LNAs .......................................................................................................... 12 2.2.1 Parallel LNAs ......................................................................................................... 12 2.2.2 Switching LNAs ..................................................................................................... 13 2.2.3 Concurrent Dual-Band LNAs ................................................................................. 15 2.3 Tunable LNAs ............................................................................................................... 16 2.3.1 Output Tuning LNAs .............................................................................................. 16 2.3.2 Input Tuning LNAs ................................................................................................ 18 CHAPTER 3. TUNABLE LNA DESIGN ........................................................................... 21 3.1 LNA Analysis ................................................................................................................ 21 3.1.1 Input Impedance ..................................................................................................... 21 3.1.2 Noise ....................................................................................................................... 23 3.1.3 Linearity.................................................................................................................. 29 3.1.4 Gain ........................................................................................................................ 30 3.1.5 Power Consumption and Area ................................................................................ 31 3.2 Magnetically Tunable Matching Network .................................................................... 31 3.3 Proposed LNA Design .................................................................................................. 41 3.3.1 Phase Shifter ........................................................................................................... 42 3.3.2 Input Impedance ..................................................................................................... 43 iii 3.3.3 Gain ........................................................................................................................ 45 3.3.4 Noise Analysis ........................................................................................................ 45 3.3.5 Stability ................................................................................................................... 49 CHAPTER 4. CIRCUIT DESIGN AND SIMULATION .................................................... 52 4.1 Proposed Tunable LNA Circuit Design ........................................................................ 52 4.2 Transformer Design....................................................................................................... 52 4.3 Simulation Results......................................................................................................... 59 CHAPTER 5. CONCLUSION ............................................................................................. 66 5.1 Future Work .................................................................................................................. 66 BIBLIOGRAPHY ................................................................................................................... 68 iv LIST OF FIGURES Fig. 1. U.S. 2011 frequency allocations. ................................................................................... 1 Fig. 2. Basic front-end radio frequency (RF) architecture. ....................................................... 3 Fig. 3. Simplified schematic of a LC bandpass filter LNA. ...................................................... 5 Fig. 4. Schematic of reactive feedback LNA. ........................................................................... 7 Fig. 5. Schematic of a resistive feedback LNA. ....................................................................... 9 Fig. 6. Schematic of a common gate input LNA. ................................................................... 10 Fig. 7. Block diagram of parallel multi-band LNA. ............................................................... 13 Fig. 8. A switching multi-band LNA. ..................................................................................... 14 Fig. 9. Schematic of a concurrent multi-band LNA. ............................................................... 15 Fig. 10. Schematic of variable capacitor tunable LNA. .......................................................... 17 Fig. 11. Schematic of a conventional narrowband LNA. ....................................................... 19 Fig. 12. Schematic of a conventional narrowband LNA. ....................................................... 22 Fig. 13. Cascade of two noisy stages. ..................................................................................... 23 Fig. 14. Conventional LNA noise sources. ............................................................................. 26 Fig. 15. Normalized noise figure plotted versus frequency and gate inductance, LG. ............ 28 Fig. 16. Normalized noise figure plotted versus frequency and source inductance, LS. ......... 28 Fig. 17. Cascade of two linear stages. ..................................................................................... 29 Fig. 18. Transformer-capacitor (TC) network. ....................................................................... 34 Fig. 19. Resonant frequency, fo, as a function of α. ................................................................ 37 Fig. 20. Resonant frequency, fo, as a function of φ, when β = 1. ............................................ 37 Fig. 21. Resonant frequency, fo, as a function of α, while sweeping coupling coefficient, k. 38 Fig. 22. Resonant frequency, fo, as a function of φ, while sweeping coupling coefficient, k. 39 v Fig. 23. Input impedance, Zin, as a function of φ while sweeping frequency. ........................ 40 Fig. 24. Proposed tunable LNA. ............................................................................................. 42 Fig. 25. Active phase shifter using a variable resonant circuit. .............................................. 43 Fig. 26. Proposed LNA design with active phase shifter. ....................................................... 44 Fig. 27. Equivalent circuit used for noise analysis. ................................................................ 46 Fig. 28. Proposed tunable LNA design. .................................................................................. 53 Fig. 29. Custom input transformer design. ............................................................................. 54 Fig. 30. Effective inductances of transformer as a function of frequency. ............................