A Novel Electrically Tunable RF Inductor With Ultra-Low Power Consumption

In this study, we propose for the first time an electrically and continuously tunable RF inductor using grounded metal oxide semiconductor (MOS) transistor as a control device. By adjusting the output resistance of the grounded MOSFET, the ground-return current can lead to a significant variation in series inductance. This proposed inductor structure was implemented in a standard CMOS process and characterized up to 30 GHz, which demonstrates maximum inductance variations of 32% and 58% at 5.8 and 18 GHz, respectively. The dc power consumption of the proposed design is kept within 50 muW over the entire tuning range.