Oscillator having a resonator coupled to an amplifier by a series resistance

摘要

An oscillator is formed by a resonator (RES) coupled to an amplifier (AMP) via a coupling path (COP). In order to counter unwanted oscillations due to parasitic resonances in the coupling path (COP), the coupling path (COP) includes a series resistance (RS). This allows better performance in terms of noise for countering unwanted oscillations, despite the fact that the series resistance is in itself a source of noise. An even better noise-performance is obtained if the coupling path (COP) also includes a series capacitance. Such a series capacitance will also effectively widen a frequency range over which the oscillator can be tuned.