A Reconfigurable Multiphase $LC$-Ring Structure for Programmable Frequency Multiplication

This brief presents a reconfigurable LC-ring structure and a programmable millimeter-wave low-power frequency multiplier that were combined together to achieve a maximum power-saving effect of 73% depending on operation modes. The proposed multiphase LC ring is reconfigurable to change the number of stages and thereby minimize current consumption depending on the number of phases necessary in an application. The programmable multiplier is implemented to reduce its current consumption by 82% through an inverter-type input circuit. A millimeter-wave frequency multiplier prototype, including the reconfigurable multiphase LC ring, was fully integrated in a 65-nm CMOS process and experimentally verified to provide programmable frequency multiplication over triple frequency bands of 12.6-15.2, 25.2-30.4, and 50.4-60.8 GHz, utilizing a 6.3 to 7.6-GHz multiphase LC ring.