A Broadband CMOS RF Front-End for Universal Tuners Supporting Multi-Standard Terrestrial and Cable Broadcasts

摘要

A wideband CMOS highly linear and low noise RF front-end including inductor-less wideband LNA, integrated passive tunable filter, harmonic rejection mixer (HRM), and loop-through amplifier (LTA) is proposed for universal tuners. The proposed inductor-less wideband LNA shows a gain range greater than 55 dB with fine gain step less than 0.5 dB while achieving higher linearity and lower noise figure (NF), as compared with the traditional resistive/active feedback LNA through a source follower (SF). The integrated tunable filter covers the entire VHF bands without dividing the frequency range by multiple filters. By adopting tunable filter and HRM simultaneously, the overall harmonic rejection ratio (HRR) of over 65 dBc is obtained. The active feedback LTA utilizing a complementary characteristic of NMOS and PMOS is proposed for supporting multiple tuner applications. The proposed RF front-end achieves a maximum voltage gain of 42 dB, a minimum NF of 4.7 dB, and CTB and CSO of under ${-}$60 dBc. The power consumption including the LTA is 144 mW at a 1.8 V supply and the chip area is 1.43 mm$^{2}$ .