A Low Jitter Digital PLL based on Mixed Mode Phase Accumulator

  • Author / Creator
    Nag, Amlan
  • Low phase noise frequency synthesizers are of primary importance in modern RF communication systems to maintain signal integrity. Since current technologies are going mobile, without much reduction of operating speed, a low phase noise TDC less digital PLL is proposed in this thesis. A dual edge sampled hybrid PD is proposed and incorporated in the PLL design. It consists of an analog S/H circuit and a hard decision circuit. The decision circuit serves as a Bang Bang PD (BBPD), while analog sampled voltage provides continuous phase error information. Mixed mode phase accumulator, which is a combination of a continuous time phase accumulator (VCO) and a discrete time phase accumulator (DTPA), is used which gives direct control over oscillator phase, without actually changing the phase/frequency of VCO. Quantization noise introduced by the BBPD is not eliminated, but bypassed in the feedback path with the help of hybrid PD and mixed mode phase accumulator without altering VCO control nodes. Therefore, this PLL generates a clean ditherless clock signal almost comparable to analog PLL. The design implementation, circuit simulation and measurement results of the proposed dither-less DPLL is presented in this dissertation. The prototype chip fabricated in 65nm CMOS process occupies a die area of 0.15275 mm2 and achieves a phase noise of -123 dBc/Hz at 1 MHz offset with 264 fs integrated jitter.

  • Subjects / Keywords
  • Graduation date
    2016-06:Fall 2016
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.
  • Language
  • Institution
    University of Alberta
  • Degree level
  • Department
    • Department of Electrical and Computer Engineering
  • Specialization
    • Integrated Circuits and Systems
  • Supervisor / co-supervisor and their department(s)
    • Hossain, Masum (Electrical and Computer Engineering)
  • Examining committee members and their departments
    • Moez, Kambiz (Electrical and Computer Engineering)
    • Elliot Duncan (Electrical and Computer Engineering)
    • Hossain, Masum (Electrical and Computer Engineering)