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8.2: Specification of Oscillator Properties

By Foster Dai
From Integrated Circuit Design for High-Speed Frequency Synthesis

8.2 Specification of Oscillator Properties

Possibly the most important characteristic of an oscillator is its phase noise. An ideal oscillator has accurate periodicity with all signal power concentrated in one discrete oscillator frequency (possibly at multiples of the oscillator frequency). However, all real oscillators have less-than-perfect spectral purity, having phase noise, which is seen as undesired frequency components around the desired frequency, as shown in Figure 8.1. It is desirable to minimize these extra frequency components as much as possible. Chapter 3 discusses the effect of oscillator phase noise on synthesizer performance. Other considerations are long-term stability and sufficient output voltage amplitude for the intended application.


Figure 8.1: Spectrum of a typical oscillator.
Copyright Artech House, Inc. 2006 under license agreement with Books24x7
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