The HPF attenuates frequencies which are below the cutoff frequency. But, in many cases a HPF is used to remove the DC level from any voltage.
For example, in this case, the IC AD5933 supplies an output voltage of 2V DC with a frequency sweep from 50 kHz to 50.5 kHz. In step 3 is used a 10 nF capacitor and 100 kOhm resistor to make the HPF, the cutoff frequency is approximately 160 Hz.
The output at the end of the HPF will be 1Vpp with the same frequency.
In this case, the purpose of attenuating frequencies below the cutoff frequency does not matter. Because the filter is only used to remove the DC component. It does not matter if the cutoff frequency is 160 Hz, 10K HZ or 20K Hz.
I have two questions.
This change of purpose confuses me. Used this way. Is the circuit a high pass filter?
How exactly does this circuit work for this purpose to remove the DC component? The value of the resistor does not make much difference, what really matters is the value of the capacitor, which should be 10n F, correct?