Electronics for Physicists: An Introduction

Description

This book provides undergraduate physics majors and students of related sciences with a sound basic understanding of electronics and how it is used, principally in the physical sciences. While today few science students go on to careers that demand an ability to design and build electronic circuits, many will use and rely on electronics. As scientists, they will require an appropriate level of fundamental knowledge that enables them, for example, to understand what electronic equipment is doing, to correctly interpret the measurements obtained, and to appreciate the numerous links between electronics and how it is practiced, and other areas of science. Discussing electronics in the broader context and from the point of view of the scientist, this book is intended for students who are not planning to become electronics specialists. It has been written in a relatively informal, personal style and includes detailed examples, as well as some “outside the box” material to inspire thought and creativity. A selection of relevant exercises is included at the end of each chapter. Preface Contents 1 The Basics Voltage and Current Simple Devices Kirchhoff’s Laws Resistors in Series Resistors in Parallel Effective Resistance Resistors in Parallel–Notation Solving Circuits with Circuit Reduction Solving Circuits with Algebra Branch and Mesh Currents Example—Using Kirchhoff’s Laws Nodal Analysis The Ideal Current Source The Ground and Common Connections Multiple Sources—The Superposition Theorem Electrical Power Additional Application—The Kelvin-Varley Divider Problems 2 Additional Theorems Thevenin and Norton Equivalents Determining the Thevenin and/or Norton Parameters How Is This Used for Circuit Reduction? Equivalent for an Infinite Array of Resistors The Wheatstone Bridge Wheatstone Bridge “Hieroglyphics” The Reciprocity Theorem Example—R-2R Ladder with Sources Delta-Y Conversion The Kelvin Bridge Additional Application—Resistivity of Lamellae Problems References 3 Complex Impedances What Is a Linear Device? Some Vocabulary Passive Linear Circuit Elements with Two Leads Idealized Sources RC and L/R Time Constants RC Time Constant Example Capacitors and Inductors with Sinusoidal Sources Superposition and Complex Impedances Series and Parallel Capacitors and Inductors Comments About Complex Arithmetic Solving Circuits Using Complex Impedances A.C. Power Condenser Microphones Problems 4 More on Capacitors and Inductors Real Capacitors and Inductors Measuring Capacitors and Inductors Capacitive Position Sensors A Simple Circuit for Measuring Inductors Switched Capacitor Methods Charging a Capacitor Efficiently Mutual Inductance and Transformers The Dot Convention for Transformers Inductive Position Sensors RLC Circuits Cable Models Cable Impedance Signal Speed in a Cable Impedance of Finite Cables Capacitor and Inductor Labels Duality Problems References 5 The Laplace Transform The Transform Laplace Transform Example 1 Method I Method II Laplace Transform Example 2 Laplace Transform Example 3 Comment on Partial Fractions Poles and Zeros Problems 6 Diodes Semiconductor Diodes Diode Models Piece-Wise Linear Diode Models An Analytic Model for the Semiconductor Diode Solving Circuits with Diodes The Ideal Diode Half-Wave Rectifier Diode Limiter Diode Clamp and Voltage Doubler Full-Wave Rectifier Graphical Solutions Example Graphical Solution Diode Ratings Diode Capacitance and Response Time Specialty and Other Diodes Problems 7 FETs Junction Field Effect Transistors Circuit Analysis with a JFET Example 1—Determine Circuit Components Example 2—Determine Operating Point The FET A.C. Model FET Amplifier Configurations The Ohmic Region MOSFETs Additional Application—Dynamic Memory Problems 8 Bipolar Junction Transistors BJT D.C. Model BJT A.C. Model BJT Large Signal Example Graphical Solutions Single Supply Operation Solutions from Parameters BJT Amplifiers Common Emitter Amplifier Example Common Collector Amplifier Example Using the Saturation Region Problems 9 More on Amplifiers Miller’s Theorem Two-Transistor Configurations The Cascode Configuration The Darlington Pair Complementary Symmetry Amplifier (“Push-Pull”) Differential Amplifier Current Mirror Silicon Controlled Rectifiers (SCR) and Triacs Connecting Amplifiers Impedance Matching Problems 10 The Ideal Op-Amp Ideal Op-Amp Properties Linear Op-Amp Circuits Example 1—Buffer Example 2—Inverting Amplifier Example 3—Non-inverting Amplifier Example 4—Difference Amplifier Example 5—Summing Amplifier Example 6—Integrator Example 7—Low-Pass Filter Example 8—Instrumentation Amplifier Example 9—A Capacitive Sensor for Smaller Values of Capacitance Example 10—Negative Resistor Example 11—Constant Current Source Other Op-Amp Circuits Example 12—Non-linear Element in Feedback Example 13—Ideal Diode Example 14—Peak Follower Example 15—Log Amplifier Example 16—Absolute Value Circuit More Power Less Than Ideal Difference Amplifiers Finite Input Resistance and Gain Finite Frequency Range Small Signals and Drift Oscillations The Transconductance Amplifier Problems References 11 Non-linear Uses of Op-Amps Limited Output Range The Op-Amp Comparator Example 1—Low-Level Warning Example 2—Pulse Generator Example 3—Simple Oscillator Example 4—A Voting Circuit Example 5—Sine to Pulse Train Converter Example 6—Zero Crossing Detector Example 7—Pulse Conditioner/Lengthener Using the Comparator for Feedback Automatic Gain Control Amplifier Putting Pieces Together Simple Phase Sensitive Detector Problems 12 Digital I Boolean Algebra Useful Rules and Theorems for Boolean Algebra Digital Logic Circuits Combinations of Digital Logic Gates Example 1—Solving with Boolean Algebra Example 2—Solving with a Truth Table Example 3—Solving Both Ways Equivalent Circuits Gates Versus Logic Functions Decoders and Encoders Multiplexing Flip-Flop Circuits Edge-Triggered Flip-Flops A Directional Electric Eye Combinations of Flip-Flops Shift Register Binary Counter Other Non-logical Applications Very Short Pulse Generator Oscillators Problems 13 Digital II Binary and BCD Numbers Binary Numbers BCD Numbers Hexadecimal and Octal Notation Other Weighted Binary Codes The 4221 Code 2 of 5 Codes Non-weighted Codes Gray Code The ASCII Code Bar Codes Interleaved 2 of 5 UPC Codes Some Numeric Code Conversions Binary to Gray Code Gray Code to Base-2 Binary Decimal to Gray Code BCD to Binary Conversion Binary to BCD Conversion Digital to Analog Conversion The 1-Bit D/A A Summing D/A Analog to Digital Conversion Voltage to Frequency Conversion Timing Schemes Search Schemes Analog to Gray Code Conversion Quantization Noise Problems Reference 14 Calculators and Computers Adding Base-2 Numbers Two’s Complement Arithmetic A Simple Arithmetic Logic Unit (ALU) Base-2 Multiplication Some Recursive Computations Compute 1/x Compute (1/x)½ Compute x½ Compute tan(x) Compute K(k) Communications Tri-state Outputs Simplified CPU Other Uses for Tri-state Devices Measuring a Small Capacitance Charlieplexing Problems References Appendix SI Units Common Unit Prefixes Fourier Series Outline placeholder The Basics How a Fourier Transform Works Complex Numbers—A Review Outline placeholder The Basics Some Complex Identities Index