How to choose CAPACITOR and INDUCTOR for High Frequency Application

Capacitor

At RF, a capacitor may be modelled as shown below;

where:
            C = capacitance
            ESR=equivalent series resistance due to heat dissipation loss expressed either as power factor or dissipation factor
            ESL= some parasitic inductance (ESL) due to electrodes

Losses in capacitor may be expressed as capacitor Q which is defined as;

According to above figure, capacitor works as a capacitor before self-resonant frequency.

Capacitor will not work as a function of capacitor after self-resonant frequency and it behave as an Inductor.

Therefore the capacitor should be chose as per below criteria.

Freq (srf) >> Freq(rf)

where:

            Freq(srf) = self-resonant frequency

            Freq(rf) = the radio frequency used in design

Inductor

At RF, an inductor may be modelled as shown below;