A Compact TSV Tunable Inductor Based on Magnetic Coupling Technique

Tunable inductors are widely recognized as a critical bottleneck in the development of fully reconfigurable and miniaturized radio frequency (RF) transceivers. Conventional designs are often limited by narrow tuning ranges, degraded high-frequency performance, large area, and fabrication complexity. In this work, a compact tunable crossover inductor is reported, which is implemented in through-silicon-via (TSV) technology. A geometry model and an equivalent circuit model are developed and are shown to be in good agreement. The tuning mechanism is derived from magnetic coupling principles, which describe the equivalent inductance under both amplitude and phase tuning regimes. The proposed inductor prototype is demonstrated to achieve continuous tuning from 0.47 to 5.93nH across 0.1–30GHz by controlling the excitation amplitude ratio and phase difference, corresponding to a tuning ratio of 92.1%. A quality factor of 63 is measured at 18GHz under in-phase modulation, and the core area is only$131\times 106~\mu $m2. These results confirm that the proposed design can be regarded as a high-performance, area-efficient tunable device for next-generation reconfigurable RF transceivers.