

Capacitor passes high frequencies, blocks low frequencies 

In frequency domain, capacitor impedance, Z(ω)=1/jωc


So, the impulse response,
where,


Whose magnitude,


And phase,


So that,


G is easiest viewed on a Bode (loglog) plot:


Φ is 0° for high frequencies, 90° at low
frequencies, and 45° at the 3dB point:


Note: The affect of a highpass filter can be numerically
undone with the droop correction algorithm.




Capacitor
passes high frequencies, blocks low frequencies 

In frequency domain, capacitor impedance,
Z(ω)=1/jωc


So, the impulse response,


where,


Whose magnitude,


And phase,


So that,


G is easiest viewed on a Bode (loglog) plot:


Φ is 0° for high frequencies, 90° at low
frequencies, and 45° at the 3dB point:




A simple algorithm can synthesize the response of input
discretetime waveform data to a lowpass RC filter. A KCL node
equation at the output node gives: 

Or, 

Which can be expressed by the implicit difference equation:


So, 
where,
