Low Power and Low Jitter Wideband Clock Synthesizers in CMOS ASICs

  • Régis Roubadia
  • Sami Ajram
  • Guy Cathébras
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4148)


This paper introduces two low power design techniques to improve both the jitter and phase noise of PLL frequency synthesizers used in ASICs. These techniques focus on the noise current reduction in wideband ring VCOs. Two PLLs embedding such VCOs were implemented, in 0.18μm and 0.13μm CMOS technologies, under 1.8V and 1.2V supply voltages respectively. The maximum improvement was observed for a 1.8V PLL running at 160MHz and consuming 1.6mW, which phase noise was reduced from -81.4dBc/Hz to -88.4dBc/Hz.


Phase Noise Noise Current Charge Pump Solid State Circuit Current Mirror 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Razavi, B.: Design of Analog CMOS Integrated Circuits. McGraw-Hill, New York (2001)Google Scholar
  2. 2.
    Hajimiri, A., Lee, T.H.: A General Theory of Phase Noise in Electrical Oscillators. IEEE Journal of Solid State Circuits 33(2), 179–194 (1998)CrossRefGoogle Scholar
  3. 3.
    Hajimiri, A., Limotyrakis, S., Lee, T.H.: Jitter and Phase Noise in Ring Oscillators . IEEE Journal of Solid State Circuits 34(6), 790–804 (1999)CrossRefGoogle Scholar
  4. 4.
    Ye, S., Jansson, L., Galton, I.: A Multiple-Crystal Interface PLL with VCO Realignment to Reduce Phase Noise. IEEE Journal of Solid State Circuits 37(12), 790–804 (2002)Google Scholar
  5. 5.
    Roubadia, R.: Theory and Design of a PLL using a realigned VCO. Master’s thesis, Univ. Montpellier 2 (2004)Google Scholar
  6. 6.
    Roubadia, R., Ajram, S.: Multi-Phase Realigned Voltage-Controlled Oscillator and Phase-Locked Loop Incorporating the same. Pending patent (April 2004)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Régis Roubadia
    • 1
  • Sami Ajram
    • 2
  • Guy Cathébras
    • 3
  1. 1.ATMEL RoussetZI RoussetFrance
  2. 2.E32 Parc DromelMarseille
  3. 3.LIRMMMontpellier

Personalised recommendations