What is Opamp: Definition and 151 Discussions

An operational amplifier (often op amp or opamp) is a DC-coupled high-gain electronic voltage amplifier with a differential input and, usually, a single-ended output. In this configuration, an op amp produces an output potential (relative to circuit ground) that is typically 100,000 times larger than the potential difference between its input terminals. Operational amplifiers had their origins in analog computers, where they were used to perform mathematical operations in linear, non-linear, and frequency-dependent circuits.
The popularity of the op amp as a building block in analog circuits is due to its versatility. By using negative feedback, the characteristics of an op-amp circuit, its gain, input and output impedance, bandwidth etc. are determined by external components and have little dependence on temperature coefficients or engineering tolerance in the op amp itself.
Op amps are used widely in electronic devices today, including a vast array of consumer, industrial, and scientific devices. Many standard IC op amps cost only a few cents; however, some integrated or hybrid operational amplifiers with special performance specifications may cost over US$100 in small quantities. Op amps may be packaged as components or used as elements of more complex integrated circuits.
The op amp is one type of differential amplifier. Other types of differential amplifier include the fully differential amplifier (similar to the op amp, but with two outputs), the instrumentation amplifier (usually built from three op amps), the isolation amplifier (similar to the instrumentation amplifier, but with tolerance to common-mode voltages that would destroy an ordinary op amp), and negative-feedback amplifier (usually built from one or more op amps and a resistive feedback network).

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  1. T

    Solving Op-Amp Current Analysis: LH0005 National Semiconductor

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  2. A

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  3. hackhard

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  4. hackhard

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  5. hackhard

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  6. W

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  7. E

    Engineering OpAmp Circuit Analysis: Finding the Differential Equation for Vo

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  8. E

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  9. D

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  10. Y

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  11. hackhard

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  12. M

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  13. K

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  14. K

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  15. kenok1216

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  16. H

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  17. Aristotle

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  18. G

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  19. C

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  20. E

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  21. R

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  22. E

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  23. E

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  24. brainbaby

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  25. brainbaby

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  26. brainbaby

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  27. G

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  28. L

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  29. R

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  30. J

    Ideal Opamp Analysis: Determine Vout for Vin = 2V & Vs = 15V

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  31. pretty_fly

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  32. 1rel

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  33. B

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  34. D

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  35. E

    Engineering How Does Changing Capacitor Value Affect OPAMP Output Voltage?

    Hi! Here is my task: OPAMP circuit and output voltag are shown in image below. Assuming that OPAMP is ideal, come up with a solution by hand. Then change capacitor's value from 200nF to 33nF and output voltage will be: Explain why output voltages are different ( first has triangle shape...
  36. E

    Engineering Solving OPAMP Circuit Analysis Problem

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  37. E

    Engineering Understanding Opamp Circuit Gain Calculation: Ideal vs. Practical Analysis

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  38. E

    Engineering Solve OPAMP Circuit Problem: Find Vo with Vin1=3V, Vin2=-2V

    Hi! Here is my task: Find output voltage Vo if Vin1=3V, Vin2=-2V, R1=R2=R3=100KΩ, R4=300KΩ, R5=150KΩ, VCC=15V. Applying KCL at node 2 we get: $$-Iin2+I5-Icc=0$$ $$-\frac{V3-V2+Vin2}{R3}+\frac{V2-V3}{R5}-\frac{V3-V2+Vcc}{R4}=0$$ $$-\frac{Vin2-V2}{R3}+\frac{V2}{R5}-\frac{Vcc-V2}{R4}=0$$...
  39. J

    Noise voltage from t-network feedback in opamp circuit

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  40. F

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  41. mishima

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  42. M

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  43. N

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  44. D

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  45. K

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  46. T

    Peculiar Opamp circuit behavior

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  47. K

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  48. K

    Finding saturation range for an opamp?

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  49. R

    Powering an OpAmp with Dual Batteries: Ground-Free Circuit Design

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  50. R

    OpAmp Non-standard Feedback

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