A 0.77 mW 2.4 GHz RF Front-End With $-$4.5 dBm In-Band IIP3 Through Inherent Filtering

This letter describes low-power design techniques that are demonstrated with a 2.4 GHz RF front-end consuming 0.77 mW while having a -4.5 dBm in-band third-order intermodulation intercept point (IIP3), a noise figure (NF) of 6.3 dB, and a spurious-free dynamic range (SFDR) up to 62.8 dB. Cross-coupling capacitors in the active mixer alleviate the gain loss due to parasitic capacitances. They also provide paths from the common sources of the switching stage to the low-noise amplifier load, forming inductor-capacitor filters that improve linearity. The proposed RF front-end was fabricated in a 130 nm CMOS process to exemplify the design techniques with specifications for ZigBee applications.