Cancellation of Series-Loss Resistance in UWB Active Inductors using RC Feedback

One of the most important features of the Active Inductors (AIs) is their input equivalent resistance, namely series-loss resistance, which should be low enough to have a high Quality Factor (QF). Most of the previous methods by this goal did not yield a high enough QF. This paper presents a new method, namely applying an RC feedback, to cancel series-loss resistance entirely. As the RC feedback cancels series-loss resistance, it enhances the Self-Resonant Frequency (SRF) as well. The SRF of the AI has a range as high as 0.25-12.5 GHz. Compared to the previous reports, the QF has been improved by applying the RC feedback. The structure is such that the QF can be adjusted independent of the SRF.