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Op Amp Builder - Level 1

Create a custom SPICE subcircuit that models Gain, Bandwidth and Input/Output Resistance. Use it early in the design cycle to develop the overall topology. This macromodel simulates quickly and convergences easily. Later in the design, replace it with a more complex model. Learn how JavaScript can create forms, SPICE models and print it to a text box.

Download a simple html/javascript page oplevel1.zip to modify/create your own model.
Check out other JavaScript Calculators.

To learn to create these SPICE op amp models:
Quick intro and Basic model

Explore the advanced OpAmpBuilder - Level 2.
Learn various op amp modelling techniques.

SPICE Circuit

Enter Op Amp Parameters

Aol		Open-loop gain (V/V(
fu		Unity-Gain Frequency (Hz) or Gain Bandwidth Product)
Rin		Input R
Rout		Output R

Enter Model Parameters

R1		Open-loop gain resistor.
Subckt Name		Name for SPICE subcircuit.
Precision (digits)		Precision for moldel values.

Calculations

KG1 = Aol / R1		Open-Loop Gain Aol = KG1 * R1.
fp1 = fu / Aol		First pole filter to acheive fu.
C1 = 1 / (2 * pi * fp1 * R1)		C1 for fp1.

To copy into text file, first move cursor into textbox above, then hit Ctrl-A and Ctrl-C.
Use Ctrl-V to paste into text file used for subcircuit.

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