A novel 0.6V CMOS folded Gilbert-cell mixer for UWB applications

A novel CMOS wideband mixer operating with only 0.6 V power supply has been designed. Such low-voltage operation is achieved by reducing threshold voltage (V_TH) of the switching transistors in the folded Gilbert cell multiplier. For input RF frequency range of 3.5-8.0 GHz and IF range of 20 MHz-2.5 GHz, the 50 W impedance matched condition is achieved, which make the proposed mixer suitable for UWB applications. The complete on-chip mixer is designed in 0.18-mum RF CMOS process. The proposed mixer exhibits a conversion gain of 11.0-5.5 dB, SSB noise-figure (NF) of 8.0-10.0 dB, and return losses (S11and S22) of less than -10 dB over frequency of 3.5-6.5 GHz. The circuit consumes only 3.75 mW from the DC power supply of 0.6 V.