Electrical Engineering - Passive Filters

The roll-off rate of a basic RC or RL filter is 20 dB per decade.

In an RL high-pass filter, the output is taken across the inductor and the output leads the input.

In an RC high-pass filter, the output is taken across the resistor and the output leads the input.

Critical frequencies are also called –3 dB frequencies.

The bandwidth of a resonant filter is determined by the quality factor (Q) of the circuit and the resonant frequency.