Patent ID: 7936235

Claim:
A tunable circuit comprising: at least one capacitive branch with at least a tunable first capacitor and tuning application means; at least one resonant branch comprising at least a second capacitor and an inductor, said second capacitor and said inductor being connected in series, wherein said at least one capacitive branch and said at least one resonant branch are connected in parallel, said tuning application means being adapted for application of a DC tuning voltage; wherein a capacitance of said first and/or second capacitor and/or an inductance of said inductor are selected such that a frequency dependency of the tunability of a varactor arrangement forming an equivalent varactor arrangement can be controlled at least in a selected frequency range; and wherein the capacitance of the second capacitor is selected to give a given frequency dependence or a frequency dependence with a given maximum deviation or tolerance in said frequency range.