Highly-linear FM transmitter for mobile application in 65nm CMOS

An FM frequency synthesizer and antenna driver with >;63dB SNR, <;0.1% THD, and -101dBc out-of band emissions at 124 dBμV output swing in 65 nm digital CMOS is described. The optimized FLL incorporates a DCO with a highly linear capacitor array and flicker noise reduction techniques. Cascaded filtering and a segmented driver improve efficiency and tuning range with minimal high-order distortion.