Divide-by-2injection-lockedfrequency divider exploiting an 8-shaped inductor

This letter presents a wide-band 2:1 injection-locked frequency divider (ILFD) in the 0.18 mu m BiCMOS process with circuit model of class-AB. The ILFD uses an 8-shaped inductor in shunt with parasitic capacitors as the resonator, and it also employs two capacitive cross-coupled pairs to generate negative resistance for oscillation. The gate biases of capacitive cross-coupled pairs are fully utilized to tune the free-running ILFD oscillation frequency. At the power consumption of 2.064 mW and the input power of 0 dBm, the locking range frequency is 71.3% (from 3.7 to 7.8 GHz) and the figure of merit (FOM) is 34.54. As compared to other ILFDs using octagonal inductors, this ILFD has low EM radiation level and less sensitivity to received EM noise.