notes/Simple RC low pass filter.md

Vout ──[ R]──●───────────  ADC
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                === C
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                GND

For a one pole low pass filter where \tau=RC and \omega is angular velocity in radians:

|H(j\omega)| = \frac{1}{\sqrt{1+{(\omega \tau)}^2}}

The -3dB point is when \omega \tau = 1, i.e. magnitude response is \frac{1}{\sqrt{2}} = 0.707

This cut off frequency is defined as $$\omega_{c} = \frac{1}{\tau}, ; f_{c} =\frac{1}{2 \pi \tau}

For a Laplace transform derivation see Worked Example RC Low Pass

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