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Still More on the 1/f2 Phase Noise Performance of Harmonic Oscillators

Pepe, Federico LU and Andreani, Pietro LU (2016) In IEEE Transactions on Circuits and Systems II: Express Briefs 63(6). p.538-542
Abstract

Modeling tank losses in a harmonic oscillator by means of an equivalent parallel resistance may lead to an optimistic estimate of phase noise, as recently experienced in a class-D CMOS oscillator. The discrepancy is significant if two conditions are fulfilled: The single-ended portion of the tank capacitance displays a non-negligible loss, and the loop gain of the oscillator is very large; in the latter case, a phase noise boost is likely to occur. In this brief, we derive phase noise equations that capture such behavior in a class-B oscillator, which is easier to approach than a class-D oscillator. The results, however, are (qualitatively) valid in general. Furthermore, the phase noise caused by the oscillator active core is always... (More)

Modeling tank losses in a harmonic oscillator by means of an equivalent parallel resistance may lead to an optimistic estimate of phase noise, as recently experienced in a class-D CMOS oscillator. The discrepancy is significant if two conditions are fulfilled: The single-ended portion of the tank capacitance displays a non-negligible loss, and the loop gain of the oscillator is very large; in the latter case, a phase noise boost is likely to occur. In this brief, we derive phase noise equations that capture such behavior in a class-B oscillator, which is easier to approach than a class-D oscillator. The results, however, are (qualitatively) valid in general. Furthermore, the phase noise caused by the oscillator active core is always proportional to the phase noise caused by the tank losses independently of the amount of phase noise boost. The agreement between theoretical and simulation results is excellent.

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author
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organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Impulse sensitivity function (ISF), oscillators, phase noise
in
IEEE Transactions on Circuits and Systems II: Express Briefs
volume
63
issue
6
article number
7407326
pages
5 pages
publisher
IEEE - Institute of Electrical and Electronics Engineers Inc.
external identifiers
  • wos:000378424300006
  • scopus:84973324719
ISSN
1549-7747
DOI
10.1109/TCSII.2016.2530438
language
English
LU publication?
yes
id
f5131d67-ca51-4da4-8b3f-ec583004ab61
date added to LUP
2016-06-23 07:38:22
date last changed
2024-06-14 10:04:30
@article{f5131d67-ca51-4da4-8b3f-ec583004ab61,
  abstract     = {{<p>Modeling tank losses in a harmonic oscillator by means of an equivalent parallel resistance may lead to an optimistic estimate of phase noise, as recently experienced in a class-D CMOS oscillator. The discrepancy is significant if two conditions are fulfilled: The single-ended portion of the tank capacitance displays a non-negligible loss, and the loop gain of the oscillator is very large; in the latter case, a phase noise boost is likely to occur. In this brief, we derive phase noise equations that capture such behavior in a class-B oscillator, which is easier to approach than a class-D oscillator. The results, however, are (qualitatively) valid in general. Furthermore, the phase noise caused by the oscillator active core is always proportional to the phase noise caused by the tank losses independently of the amount of phase noise boost. The agreement between theoretical and simulation results is excellent.</p>}},
  author       = {{Pepe, Federico and Andreani, Pietro}},
  issn         = {{1549-7747}},
  keywords     = {{Impulse sensitivity function (ISF); oscillators; phase noise}},
  language     = {{eng}},
  month        = {{06}},
  number       = {{6}},
  pages        = {{538--542}},
  publisher    = {{IEEE - Institute of Electrical and Electronics Engineers Inc.}},
  series       = {{IEEE Transactions on Circuits and Systems II: Express Briefs}},
  title        = {{Still More on the 1/f<sup>2</sup> Phase Noise Performance of Harmonic Oscillators}},
  url          = {{http://dx.doi.org/10.1109/TCSII.2016.2530438}},
  doi          = {{10.1109/TCSII.2016.2530438}},
  volume       = {{63}},
  year         = {{2016}},
}