A 3.3 volt high-frequency capacitorless electronically-tunable log-domain oscillator

Abstract

A new type of electronically tunable oscillator using a cascade of two capacitorless first order log-domain all-pass filters as the frequency and the gain controlling element is proposed, where it is shown that the log-domain circuit technique is ideally suited for implementation of electronically tunable oscillators, The resulting oscillator enjoys several attractive properties, namely, low supply voltage, high oscillation frequencies, wide tuning range and relatively large oscillation levels can be obtained without excessive distortions, as oppose to previously reported forward-biased diode based electronically tunable oscillators.