US Patent 7696840 RF selection switch for multiple antenna input

RF switches are known from the art for selecting an RF signal from a multiple of inputs. For instance a TV-tuner and TV-Front-end can have two or more antenna inputs but are implemented with a relative bad cost performance. The present invention relates to an RF selection switch circuit (200). The switch comprises a first switch (202), a second switch (204) with both an RF input port and a common RF output port a control signal circuitry (206). In a preferred embodiment the switches comprise pin-diodes. The RF output port comprises two transistors (T1, T2), one of which at a time can put the non-selected switch to a low-impedance level in order to minimize signal leakage the common output port.