JAJSHS8E June 2011 – August 2019 TPA6211A1-Q1
Because the application in this case requires a gain of 4 V/V, RI must be set to 10 kΩ.
Substituting RI into Equation 25.
Substituting 100 Hz for fc(HPF) and solving for CI:
At this point, a first-order band-pass filter has been created with the low-frequency cutoff set to 100 Hz and the high-frequency cutoff set to 10 kHz.
The process can be taken a step further by creating a second-order high-pass filter. This is accomplished by placing a resistor (Ra) and capacitor (Ca) in the input path. Ra must be at least 10 times smaller than RI; otherwise its value has a noticeable effect on the gain, as Ra and RI are in series.