26 lines
530 B
Markdown
26 lines
530 B
Markdown
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Written by ChatGPT but checked against the data-sheet calculations.
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#!/usr/bin/env python3
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"""
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2nd-order unity-gain Butterworth Sallen-Key low-pass calculator
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Based on TI SBOA226 design steps:
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Usage:
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For 22k resistors and a cut-off $f_c$ of 500Hz:
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$ python3 --R 22E3 500
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![[butter_plot.py]]
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![[butter_plot.py]]
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## Example
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$ python3 butter_plot.py --R 22E3 500
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2nd-order unity-gain Butterworth Sallen-Key LPF (ideal)
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fc = 0.5 kHz
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R1=R2= 22 kohm
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C1 = 20.46 nF (norm 1.414)
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C2 = 10.23 nF (norm 0.707)
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Q = 0.707107
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