A Reversible Poly-Phase Distributed VCO

A reversible 24-phase closed-loop distributed VCO is implemented in 90nm 10M triple-well 1.2V CMOS using co-planar transmission lines as delay elements. The measured tuning range is 10.4 to 11.4GHz, the phase noise is -96.65dBc/Hz at 1MHz offset, and the circuit uses 70mW from a 1.2V supply