Linear Integrated Circuits and its Applications Linear Integrated Circuits and its Applications 1 Contents Foreword ............................................................................................................................................. 11 1 Introduction to Operational Amplifiers and Characteristics ..................................................... 13 1.1 Introduction .............................................................................................................................................. 14 1.2 Linear integrated circuits and op-amp ...................................................................................................... 15 1.3 Block diagram ........................................................................................................................................... 16 1.4 Characteristics and equivalent circuits of an ideal op-amp ...................................................................... 17 1.4.1 Characteristics of Ideal Op-amp: .................................................................................................... 18 1.4.2 Equivalent circuit of op-amp ........................................................................................................... 19 1.5 Various Types of operational amplifiers and applications ........................................................................ 20 1.6 Power Supply Configurations of Op-Amp ................................................................................................. 21 1.7 Inverting and non inverting amplifier configurations ................................................................................. 23 1.7.1 Open loop operation of Op-Amp ................................................................................................ 23 1.7.2 Closed loop configuration of Op-Amp ............................................................................................ 24 1.7.3 Inverting-configuration using ideal op amp .................................................................................... 25 1.7.4 Non Inverting-configuration using ideal op amp ............................................................................. 26 1.8 Summary ................................................................................................................................................... 28 1.9 Review Questions ..................................................................................................................................... 29 1.10 Exercises: ................................................................................................................................................ 30 2 Practical Operational Amplifiers ................................................................................................. 32 2.1 Introduction ............................................................................................................................................... 33 2.2 Effect of Finite Loop Gain on Closed Loop Gain ...................................................................................... 34 2.3 Effect of finite loop gain on Input Resistance Rin ...................................................................................... 42 2.4 Effect of finite gain on output resistance Rout ............................................................................................ 44 2.5 Voltage follower or Buffer Amplifier .......................................................................................................... 47 2.6 Input offset and Input Bias current ............................................................................................................ 49 2.7 Input Offset Voltage .................................................................................................................................. 53 2.8 Thermal Drift ............................................................................................................................................. 55 2.9 Common Mode Rejection ratio (CMRR) ................................................................................................... 57 2.10 Slew rate and its effects .......................................................................................................................... 59 2.11 Power Supply Rejection Ratio (PSRR) ................................................................................................... 60 2.12 Frequency Response .............................................................................................................................. 61 2.12.1 Frequency Response of Non Inverting Amplifier ......................................................................... 63 2.12.2 Frequency Response of Inverting Amplifier ................................................................................. 65 2.12.3 Frequency response with double pole ......................................................................................... 67 2.13 Interpretation of TL082 Data sheet ......................................................................................................... 68 2.13.1 Introduction ................................................................................................................................... 68 2 Linear Integrated Circuits and its Applications www.ti.com 2.13.2 General Classification of Op-amps .............................................................................................. 68 2.13.3 About TL082 ................................................................................................................................. 69 2.13.4 Major features of TL082 ............................................................................................................... 70 2.13.5 List of common data sheet parameters ........................................................................................ 70 2.13.6 DC and AC Electrical Characteristics........................................................................................... 72 2.13.7 Application Notes for TL082 ......................................................................................................... 72 2.14 Summary ................................................................................................................................................. 73 2.15 Review Questions ................................................................................................................................... 74 2.16 Exercises ................................................................................................................................................. 75 3 Amplifiers and Oscillators ........................................................................................................... 76 3.1 Introduction ............................................................................................................................................... 77 3.2 Summing amplifier .................................................................................................................................... 78 3.2.1 Inverting Summing Amplifier .......................................................................................................... 78 3.2.2 Inverting Summing Amplifier with Unity Gain ................................................................................. 79 3.2.3 Inverting Summing Amplifier with Gain Greater than Unity ........................................................... 79 3.2.4 Non-inverting Summing Amplifier ................................................................................................... 79 3.3 Averaging Amplifier ................................................................................................................................... 81 3.4 Scaling Amplifier ....................................................................................................................................... 82 3.5 Integrator .................................................................................................................................................. 83 3.6 Differentiator.............................................................................................................................................. 86 3.7 Instrumentation amplifier ........................................................................................................................... 89 3.8 Differential Input and Differential Output Amplifiers .................................................................................. 92 3.8.1 Differential Input Amplifier .............................................................................................................. 92 3.8.2 Differential Output Amplifier ........................................................................................................... 93 3.9 Feedback Amplifiers ................................................................................................................................. 94 3.9.1 Voltage series feedback amplifier .................................................................................................. 96 3.9.2 Voltage shunt feedback amplifier ................................................................................................. 100 3.10 Log / Antilog Amplifiers ........................................................................................................................