A 50 GHz direct injection locked oscillator topology as low power frequency divider in 0.13 /spl mu/m CMOS

An injection locked oscillator topology is presented, based on MOS-switches directly coupled to the LC-tank of well-known LC-oscillators. The direct injection locking scheme features a very low input capacitance and high frequency capability. The functionality of the direct locking is verified through two test circuits in 0.13 /spl mu/m standard CMOS. With a power consumption of 3 mW, one oscillator divides 50 GHz by two with a locking range of 80 MHz. Also at a power consumption of 3 mW, the second oscillator with a lower Q tank divides 42 GHz by two with a locking range of 1.5 GHz.