Inverting Operational amplifier

Click For Summary
SUMMARY

The discussion focuses on the input and output impedance characteristics of inverting and non-inverting operational amplifiers (op-amps). For the inverting op-amp configuration with R1 set at 1000 ohms and Rf at 10^6 ohms, the input impedance is confirmed to be 1000 ohms while the output impedance is effectively 0. In contrast, the non-inverting op-amp, with R1 at 3500 ohms and Rf at 15000 ohms, theoretically has infinite input impedance, applicable only to ideal op-amps. The input impedance for real non-inverting op-amps ranges from 1 MΩ to 10 TΩ, indicating significant differences between ideal and practical scenarios.

PREREQUISITES
  • Understanding of operational amplifier configurations
  • Knowledge of impedance concepts in electronics
  • Familiarity with resistor values and their impact on circuit behavior
  • Basic principles of ideal vs. real op-amps
NEXT STEPS
  • Study the characteristics of ideal vs. real operational amplifiers
  • Learn about feedback mechanisms in op-amp circuits
  • Explore the implications of input and output impedance in circuit design
  • Investigate the applications of operational amplifiers in signal processing
USEFUL FOR

Electronics students, circuit designers, and engineers interested in understanding operational amplifier behavior and its implications in practical applications.

Amith2006
Messages
416
Reaction score
2

Homework Statement


1) Consider an inverting operational amplifier as shown in figure. Suppose R1= 1000 ohm & Rf = 10^6 ohm. It is said that the input impedance=R1=1000 ohm and the Output impedance= 0.

2) Consider a non inverting operational amplifier as shown in figure. Suppose R1= 3500 ohm & Rf = 15000 ohm. It is said that the input impedance=infinite. Why is it so? Here Rf is the feedback resistor.But only for an ideal Op-Amp, the input impedance is infinite and not for a real one, isn’t it? So, can R1 be taken as the input impedance of the Op-Amp in both cases?


Homework Equations





The Attempt at a Solution

 

Attachments

  • img182.gif
    img182.gif
    2 KB · Views: 592
  • img184.gif
    img184.gif
    2 KB · Views: 546
Physics news on Phys.org
These are a couple of links that explain the input impedance for both op amps.
http://www.phys.uAlberta.ca/~gingrich/phys395/notes/node102.html
http://www.phys.uAlberta.ca/~gingrich/phys395/notes/node103.html

For a real non inverting op amp, the input impedance is somewhere between 1 MΩ to 10 TΩ.
 
Last edited by a moderator:

Similar threads

  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 6 ·
Replies
6
Views
3K
Replies
15
Views
3K
  • · Replies 12 ·
Replies
12
Views
2K
Replies
34
Views
4K
  • · Replies 4 ·
Replies
4
Views
6K
  • · Replies 20 ·
Replies
20
Views
7K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 4 ·
Replies
4
Views
4K