Measurement Computing PC104-DIO48 - Manual (Page 22)

A simple low-pass filter may be constructed from one resistor (R) and
one capacitor (C) (Figure 5-3). The cut-off frequency is determined
according to the formula:
Fc = 1 Where
π
= 3.14...
2
π
R C R = ohms
C = farads
and
R =
1 Fc = cut-off frequency in cycles/second.
2
π
C Fc
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