A highly linear super-source-follower-based reconfigurable RF filter with wide tuning range for TV receiver applications

摘要

A highly linear super-source-follower (super SF) based reconfigurable RF filter with wide tuning range is proposed for TV receiver applications. By converting the polarity of the differential output signals of the super SF through CMOS switches, the transfer function of the conventional Sallen-Key (SK) filter can be easily changed to have lower 3-dB cutoff frequency without increasing the total capacitance of the switched capacitor array. This greatly reduces the chip size of the proposed tunable filter while maximizing the frequency tuning range. The proposed tunable SK filter was implemented in 0.13 μm CMOS technology. In the post-layout simulation, the proposed SK filter 76MHz ~ 1.6 GHz frequency tuning range, NF of less than 14.7dB. The power consumption of the tunable filter excluding input/output buffer is 31.8 mW at a 1.2 V supply.