A Closed-Loop Impedance Tuner with Integrated Reflectometer and High-Voltage Tuning Switches

In this work, a closed-loop radio frequency (RF) frontend impedance tuning system with high-voltage impedance tuning switches monolithically integrated with an RF reflectometer is presented. An RF application-specific integrated circuit (ASIC) integrating a low-power scalar RF reflectometer and two RF tuning switches is designed and manufactured in 90nm RF SOI CMOS switch technology. A hardware prototype closed-loop tuning system is built with the designed ASIC along with a commercial impedance tuning IC, aiming for tuning at operating frequencies between 690 and 900MHz . The circuit can process signals with power greater than 18dBm , while the RF voltage handling capability reaches 63V with the linearity of IIP3=84dBm in the signal path. The designed ASIC consumes 46μW and 184μW in idle and conversion mode, respectively.