1.2-V folded down-conversion wideband mixer in 65-nm CMOS

This paper presents the design of a low-voltage folded down-conversion mixer for direct conversion receiver. The RF-transconductance stage of the mixer is based on an AC-coupled stacked NMOS-PMOS current reuse topology. The mixer has a peak conversion gain (CG) of 8 dB with a 3-dB bandwidth from 10.25 GHz to approximately 17.8 GHz (IF ranges from DC to 6.5 GHz). The LO center frequency for the mixer is fixed at 12 GHz and RF input band with respect to center frequency is from 10.25 GHz to 13.75 GHz. It displays an OIP3 of 9.76 dBm. The minimum SSB-NF is 8.2 dB with a flicker noise corner frequency of 250 kHz. It has an IIP2 in excess of 50 dBm. The mixer draws a current of 12 mA from a 1.2-V supply.