Ultra-low power, low-voltage transmitter at ISM band for short range transceivers

Abstract

Tezin basılısı İstanbul Şehir Üniversitesi Kütüphanesi'ndedir.The increasing demand for technology to be used in every aspect of our lives has led the way to many new applications and communication standards. WSN and BAN are some of the new examples that utilize electronic circuit design in the form of very small sensors to perform their applications. They consist of small sensor nodes and have applications ranging from entertainment to medicine. Requirements such as decreasing the area and the power consumption help to have longer-lasting batteries and smaller devices. The standard paves the way for the devices from different vendors to communicate with each other, and that motivates us to make designs as compatible with the standard as it can be. In this thesis, an ultra-low power high efficient transmitter with a small area working at 2.4 GHz have been designed for BAN applications. A study on the system-view perspective is important in optimizing the area and power since the transmitter architecture can change the circuit design. From a circuit design perspective, seeking to decrease power consumption means thinking of new techniques to implement the same function or a new system. Inspired by new trends, this research presents a design solution to the previously mentioned problem and hopefully, after fabrication, the measured results will match the simulated results to prove the validity of the design.Declaration of Authorship ii Abstract iv Öz v Acknowledgments vii List of Figures x List of Tables xiii Abbreviations xiv 1 Introduction 1 1.1 Background and Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Communication Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2.1 Digital Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.2.2 Unwanted Power Limitations . . . . . . . . . . . . . . . . . . . . . 3 1.2.3 Multiple Access Techniques . . . . . . . . . . . . . . . . . . . . . . 3 1.3 Transmitter System Level Specifications . . . . . . . . . . . . . . . . . . . 4 1.3.1 Low Power Wireless Standards . . . . . . . . . . . . . . . . . . . . 4 1.4 Low-Power Wireless Transceiver systems . . . . . . . . . . . . . . . . . . . 6 1.4.1 Survey of the previous work . . . . . . . . . . . . . . . . . . . . . . 7 1.4.2 The Designed Transmitter System . . . . . . . . . . . . . . . . . . 8 1.5 Ultra-Low Power Transmitters Performance Metrics . . . . . . . . . . . . 9 1.6 Thesis Contribution and Outline . . . . . . . . . . . . . . . . . . . . . . . 10 2 Circuit Design for The Transmitter 11 2.1 Technology Characterization and Modeling for Low-Power Designs . . . 11 2.1.1 Passive Components modeling . . . . . . . . . . . . . . . . . . . . 11 2.1.2 Active Components Modeling . . . . . . . . . . . . . . . . . . . . . 13 2.1.3 MOS Transistor Sub-threshold Modeling . . . . . . . . . . . . . . 13 2.1.4 MOS Transistor Simulation-Based Modeling . . . . . . . . . . . . . 14 2.2 Low-Voltage Low-Power Analog and RF Design Principles . . . . . . . . . 17 2.2.1 Separate Gate Biasing of The Inverter . . . . . . . . . . . . . . . . 17 2.2.2 Body Biasing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.3 Low-Voltage Analog Mixed Biasing Circuit Designs . . . . . . . . . . . . . 18 2.3.1 DAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.3.2 Operational Amplifier Design . . . . . . . . . . . . . . . . . . . . . 19 2.4 Crystal Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 2.4.1 The MEMS Crystal . . . . . . . . . . . . . . . . . . . . . . . . . . 22 2.4.2 Crystal Oscillator Topologies . . . . . . . . . . . . . . . . . . . . . 23 2.4.3 Design of The CMOS Crystal Oscillator . . . . . . . . . . . . . . . 26 2.5 Pre-Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 2.6 OOK Modulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 2.7 BPSK Modulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 2.8 Digital Control of the Modulators . . . . . . . . . . . . . . . . . . . . . . . 35 2.9 Power Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 2.9.1 ULP PA Topologies Survey . . . . . . . . . . . . . . . . . . . . . . 38 2.9.2 The Push-Pull PA Design Methodology . . . . . . . . . . . . . . . 41 2.10 Transmit/Receive (T/R) Switch . . . . . . . . . . . . . . . . . . . . . . . 43 2.10.1 T/R Switch Topologies . . . . . . . . . . . . . . . . . . . . . . . . . 43 2.10.2 Suggested Low-Area Low-Voltage RF Switch . . . . . . . . . . . . 46 3 Transmitter Integration and Final Results 48 3.1 Transmitter Simulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 3.2 Transmitter Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 3.3 Results Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 3.4 Results Comparison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 4 Conclusions 59 4.1 Thesis Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 4.2 Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 A Bond Wire Parasitic Modeling 61 B Crystal Oscillator With Parasitic Effects 67 B.1 Simulation of FBAR with Parasitic Effects . . . . . . . . . . . . . . . . . 67 B.2 Root Locus Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 Bibliography 7