Javascript verkar inte påslaget? - Vissa delar av Lunds universitets webbplats fungerar inte optimalt utan javascript, kontrollera din webbläsares inställningar.
Du är här

Class-C Harmonic CMOS VCOs, With a General Result on Phase Noise

Publiceringsår: 2008
Språk: Engelska
Sidor: 2716-2729
Publikation/Tidskrift/Serie: IEEE Journal of Solid-State Circuits
Volym: 43
Nummer: 12
Dokumenttyp: Artikel i tidskrift
Förlag: IEEE--Institute of Electrical and Electronics Engineers Inc.


A harmonic oscillator topology displaying an improved

phase noise performance is introduced in this paper.

Exploiting the advantages yielded by operating the core transistors

in class-C, a theoretical 3.9 dB phase noise improvement

compared to the standard differential-pair LC-tank oscillator

is achieved for the same current consumption. Further benefits

derive from the natural rejection of the tail bias current noise,

and from the absence of parasitic nodes sensitive to stray capacitances.

Closed-form phase-noise equations obtained from a

rigorous time-variant circuit analysis are presented, as well as a

time-variant study of the stability of the oscillation amplitude,

resulting in simple guidelines for a reliable design. Furthermore,

the analysis of phase noise is extended to encompass a general harmonic

oscillator, showing that all phase noise relations previously

obtained for specific LC oscillator topologies are special cases of a

very general and remarkably simple result.

Two prototypes of the (voltage-controlled) oscillator are

implemented in a standard RF 0.13 m CMOS technology.

They are tunable over the frequency bands 4.90-5.65 GHz and

4.50–5.00 GHz, respectively, and display an average phase noise

lower than 130 dBc/Hz @ 3 MHz from the carrier with a power

consumption of 1.4 mW, for a state-of-the-art figure-of-merit

ranging from 193.5 dBc/Hz to 196.0 dBc/Hz.


  • Electrical Engineering, Electronic Engineering, Information Engineering


  • Data converters & RF-lup-obsolete
  • ISSN: 0018-9200

Box 117, 221 00 LUND
Telefon 046-222 00 00 (växel)
Telefax 046-222 47 20
lu [at] lu [dot] se

Fakturaadress: Box 188, 221 00 LUND
Organisationsnummer: 202100-3211
Om webbplatsen