A Tuneable Active Inductor With High Dynamic Range for Band-Pass Filter Applications

Abstract

An approach for the design of high- <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Q</i> active inductor (AI) with high dynamic range is presented. The proposed AI includes a passive variable phase- and amplitude-compensating network and a highly linear inverting amplifier, forming a gyrator-C architecture. The equivalent inductance and resistance values are tunable in a wide frequency range; outside the operating frequency band, the inductor equivalent resistance increases, improving signal rejection for band-pass filter applications. As a feasibility demonstration, a first-order active band-pass filter using the high- <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Q</i> active inductance has been fabricated and tested. The filter has a center frequency of 600 MHz and a measured noise figure of 11 dB with a 5-dBm 1-dB compression point and an 82-dB dynamic range.