1 / 34

Mastering Operational Amplifiers in Electrical Circuits

Learn about definitions, basics, and practical applications of op amps in circuits. Explore inverting, non-inverting, and summing amplifiers. Practice integrating and differentiating amplifiers with real-world scenarios.

pmello
Download Presentation

Mastering Operational Amplifiers in Electrical Circuits

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ECE 4991 Electrical and Electronic CircuitsChapter 8

  2. Where are we? • Chapter 2 - The basic concepts and practice at analyzing simple electric circuits with sources and resistors • Chapter 3 – More harder networks to analyze and the notion of equivalent circuits • Chapter 4 – Capacitors and inductors added to the mix • Chapter 5 – Analyzing transient situations in complex passive networks • Chapter 8 – New subject – the wonders of operational amplifiers as system elements • Chapter 9 – Introduction to semiconductors – the basics and diodes – more network analysis • Chapter 10 – Bipolar junction transistors and how they work – now you can build your own op amp

  3. What’s Important in Chapter 8 • Definitions • Op Amp Basics • Inverting Amplifiers • Summing Amplifiers • Non-inverting Amplifiers • Voltage Followers • Diff Amps • Integrators • Differentiators

  4. 1. Definitions • Operational Amplifier • Open-loop • Feedback • Inverting (input) • Non-inverting (input) • Open-loop voltage gain

  5. 2. Op Amp Basics • An operational amplifier is an IC “engine” that can support many applications • Defining characteristics • Amplifies difference between two input voltage • Extremely high gain • Extremely high input resistance • Extremely low output resistance

  6. _ + Diagramming an Op Amp + Pwr Inverting Input Output Non-inverting Input _ Pwr

  7. Design Assumptions Two main design assumptions for op amp applications using negative feedback • Zero input current • Input voltages forced to be equal

  8. _ + 3. Inverting Amplifier • + input grounded • Input signal to (–) input through RS • Output fed back to (–) input through RF • Gain = - RF/RS

  9. _ + Inverting Amplifier Practice • Design an inverting amplifier with a gain of - 250

  10. _ + Inverting Amplifier Practice • Given the following resistors to work with – 1KΩ, 1KΩ, 3KΩ, 20KΩ, 30KΩ – design an inverting amp with gain -40

  11. _ + 4. Summing Amplifier • + input grounded • Several input signals to (–) input through RS’s • Output fed back to (–) input through RF • Vout = -  (RF / RSi) vsi

  12. _ + Summing Amplifier Practice • Design an amplifier with Vout = - 50 (v1 + v2 + v3)

  13. _ + Summing Amplifier Practice • Design an amplifier with Vout = - (20v1 +30v2 + 40v3)

  14. _ + 5. Non-Inverting Amplifiers • Ground the (-) input through RS • Signal input to + input through any R • Output fed back to (-) input through RF • Gain is 1 + RF / RS

  15. _ + Non-Inverting Amplifier Practice • Design a non-inverting amp with gain = 10

  16. _ + Non-Inverting Amplifier Practice • Resistor collection is 20Ω, 50Ω, 100Ω, 100Ω, 300Ω, 300Ω, 500Ω • Design a non-inverting amplifier with a gain of 5

  17. _ + 6. Voltage Follower • Output fed back directly to (-) input • Signal input directly to + input • Vout = vS

  18. What’s a Voltage Follower For? • Op amp input impedance very high • Op amp output impedance very low • Voltage followers buffer sensitive circuits or circuit elements • Also used for driving speakers, long cables, etc

  19. _ + 7. Differential Amplifiers • V1 input fed to (-) input through R1 • V2 input fed to + input through a different R1 • Output tied back to (-) input through R2 • + input tied to ground through R2 • Vout = (R2/R1) (V2 – V1)

  20. _ + Differential Amplifier Practice • Design a diff amp with Vout = 50 (V2 – V1)

  21. _ + Differential Amplifier Practice • Design a diff amp with Vout = 200 sin t – 600 cos 3t

  22. _ + Differential Amplifier Practice • Design a diff amp with Vout = 40 sin t – 10 V1

  23. _ + 8. Integrating Amplifiers • Signal input fed to (-) input through RS • Output tied back to (-) input through CF • + input tied to ground • Vout = - (1/RSCF)  VS dt

  24. _ + Integrating Amplifier Practice • VS = 4 sin t, RS = 100 , CF = 50 F • Vout = ?

  25. _ + Integrating Amplifier Practice • Vout = - 200 t4 Volts • VS = ?, RS = 1K, CF = ?

  26. _ + 9. Differentiating Amplifiers • Signal input fed to (-) input through CS • Output tied back to (-) input through RF • + input tied to ground • Vout = - RFCS dVS/dt

  27. _ + Differentiating Amplifier Practice • Vout = - RFCS dVS/dt • Design a differentiating amplifier with Vout = 30 sin t

  28. _ + Differentiating Amplifier Practice • Vout = - RFCS dVS/dt • VS = 25 sin 2t, RF = 100, CS = 10 F • Vout = ?

  29. _ + Op Amp Practice

  30. _ + Op Amp Practice

  31. _ + Op Amp Practice

  32. _ + Op Amp Practice

  33. _ + Op Amp Practice

  34. _ + Op Amp Practice

More Related