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Op Amp Models 
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► BASIC OP AMP MODEL  Level 1 You've probably seen op amps in a variety of applications, but how do you simulate them? Here's a good place to start  the three basic stages of an op amp: 1) Differential Amplifier, 2) Gain / Frequency Response and 3 ) Output Buffer. Using basic SPICE devices, this model helps you simulate the frequency response and DC accuracy of your amplifier.
► INTERMEDIATE MODEL  Level 2 This SPICE model (Boyle style) is beginning to look like those created by many op amp manufacturers. Only slightly more complex than the basic model, it includes slew rate limiting. But, the main benefit is that many advanced behaviors  voltage and current limit, CMR behavior, additional poles and zeros  can be easily added to this model (see Level 3 model below.) You can download an Excel spreadsheet that calculates the component values given an op amp's specifications.
► ADVANCED COMPONENTS  Level 3 Learn to model advanced analog behaviors with the Level 3 Op Amp models. Each SPICE file below adds an advanced function  one at a time  to the Level 2 Op Amp Model. Take the functions you need, modify them if you like, or create your own op amp model.
► EASYTOUSE FUNCTIONS Here are some alternative  and typically easier  ways to implement various op amp functions.
OP AMP MODEL SUMMARY


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