Academic Year 2019/2020 - 3° Year

ING-INF/01 - 9 CFU - 1° Semester

The course aims at providing basic knowledge about the modeling of electronic devices, about the operation of analog and digital circuits in CMOS technology and about the most common circuit configurations that make use of operational amplifiers. The course also provides knowledge of CAD software (for example LTSPICE) for circuit simulation.

At the end of the course the student will have an overview of the electronic devices and applications in which they are used and will be able to analyze and design simple analog and digital circuits, also through the use of CAD tools.

The course includes lectures and both numerical and simulation exercises (CAD). The latter are aimed at putting into practice and consolidating the theoretical contents as well as the analysis and the design techniques developed. Seminars will be organized by researchers and designers from companies operating in the microelectronics sector.

**Introduction to Electronics:**A brief history of electronics. Classification of Electronic Signals. A/D and D/A Converters. Notational Conventions. Dependent sourced. Important Concepts from Circuit Theory (Kirchhoff’s lows, dividers, Thevenin and Norton Equivalents). Frequency Spectrum of Electronic Signals. Amplifiers. Example: FM receiver**Solid-State Electronics**. Solid-State Electronic Materials. Covalent Bond Model. Intrinsic carrier concentration. Mass action. Drift Currents and Mobility in Semiconductors. Velocity Saturation. Resistivity of Intrinsic Silicon. Impurities in Semiconductors. Electron and Hole Concentrations in Doped Semiconductors. Diffusion Currents. Total Current. Energy Band Model.**Solid-state Diodes and Diode circuits:**Junction diode. The I/V Characteristics of the Diode. Diode Characteristics Under Reverse, Zero, and Forward Bias. Diode Temperature Coefficient. Reverse Breakdown and Zener Diode. pn Junction Capacitance in Reverse Bias and Forward Bias. Dynamic Switching Behavior of the Diode. Large signal Model. Diode SPICE Model. Diode Circuit Analysis. Load-Line Analysis. Analysis Using the Mathematical Model for the Diode (small signal resistance). Constant Voltage Drop Model. Multiple-Diode Circuits. Half-Wave Rectifier Circuits with R, C and RC load. Full-Wave Rectifier and Bridge Circuits. Voltage regulator with Zener diode. Photo Diodes and Photodetectors. Schottky Barrier Diodes. Solar Cells. Light-Emitting Diodes**MOS Transistors:**Characteristics of the MOS Capacitor. Accumulation Region. Depletion Region. Inversion Region. The NMOS Transistor. Qualitative I/V Behavior of the NMOS Transistor. Triode Region Characteristics of the NMOS Transistor. On Resistance. Saturation of the I/V Characteristics. Mathematical Model in the Saturation (Pinch-Off) Region Transconductance. Channel-Length Modulation. Body Effect. PMOS Transistors. MOSFET Circuit Symbols. NMOS Transistor Capacitances in the Triode Region. Capacitances in the Saturation Region. Capacitances in Cutoff. MOSFET biasing (4 resistors network) and analysis. Modeling in SPICE.**Digital circuits**: Ideal Logic Gates. *Logic Level Definitions and Noise Margins. Logic Gate Design Goals. Dynamic Response of Logic Gates. Rise Time and Fall Time. Propagation Delay. Power-Delay Product. Review of Boolean Algebra. CMOS logic circuits. Static characteristics of the CMOS Inverter. CMOS Voltage Transfer Characteristics. CMOS NOR and NAND Gates. Design of Complex Gates in CMOS. Cascade Buffers and Delay Model. Optimum Number of Stages. Bistable latch. SR Flip-Flop. JK Flip flop. Flip-Flop race condition. The D-Latch Using Transmission Gates. Master-Slave Flip-Flop. Edge triggered Flip flop. Counters and registers. Random Access Memories (RAMs). 6-T cell. Dynamic RAMs. 1-T cell.**Operational Amplifiers:**An Example of an Analog Electronic System. Amplification. Voltage Gain, Current Gain and Power Gain. The Decibel Scale. The Differential Amplifier. Differential Amplifier Voltage Transfer Characteristic. Differential Voltage Gain. Differential Amplifier Model. Ideal Operational Amplifier. Assumptions for Ideal Operational Amplifier. The Inverting Amplifier. The Transresistance Amplifier. The Noninverting Amplifier. The Unity-Gain Buffer, or Voltage Follower. The Summing Amplifier. The Difference Amplifier. The Integrator. The Differentiator. Nonidealities: Common mode gain. CMRR. I/O resistances. Offset. Slew rate.**Small-signal Modeling and linear amplification:**The Transistor as an Amplifier. Coupling and Bypass Capacitors. Circuit Analysis Using dc and ac Equivalent Circuits. Small-Signal Modeling of the Diode. Small-Signal Models for Field-Effect Transistors. Intrinsic Voltage Gain of the MOSFET. The Common-Source Amplifier (Voltage Gain. I/O resistances). Power dissipation and signal swing. Amplifiers classification. CS, CD, CG configurations. CS with resistive degeneration. AC-coupled multi stage amplifiers.**Current Mirrors:**DC analysis of MOS current mirrors. Changing the MOS Mirror Ratio. Cascode current mirror.**Frequency response:**Frequency response of Amplifiers, Midband gain, Low and high cutoff frequencies (fL and fH). Estimation of f_{L}through the short-circuit time constant method for CS, CG, CD amplifier. High-frequency MOSFET model. Transition frequency, f_{T}. Channel Length Dependence of f_{T}. Analisi ad alta frequenza dell’amplificatore source comune. L’effetto Miller. High-Frequency C-S Amplifier Analysis. The Miller Effect. Common-Emitter and Common-Source Amplifier High-Frequency Response. Estimation of f_{H}through the open-circuit time constant method for CS.**Computer****simulations of electronic circuits:**LTSPICE.

1. Jaeger-Blalock, Microelettronica Ed. Mc-Graw-Hill V Edizione.

2. Sedra-Smith, Circuiti per la Microelettronica, Edises.