Tunable integrated RF filter having switched field effect capacitors

摘要

A filter (3) is described, which filter is provided with field effect (FET) capacitors (M1-32; M'1-32) arranged for controlling their respective capacity values, each such FET capacitor (M1-32; M'1-32) having a source (S) and a drain (D). The source (S) and the drain (D) of each FET capacitor (M1-32; M'1-32) are coupled to one another. The filter acting as an impedance transformer is a passive low power consuming and tunable filter, such as for a radio frequency (RF) receiver. It occupies only a very small area, while integrated on chip.