Low jitter frequency multiplier
Yin, Jee Khoi
Date of Issue2010
School of Electrical and Electronic Engineering
This thesis I explore the research in the area of low jitter frequency multipliers before proposing a novel new design for such a multiplier. The thesis begins with an analysis of the random and deterministic noise arising from conventional phaselocked loop (PLL) and delay-locked loop (DLL) based frequency multipliers. Although the DLL is a better candidate for use as a low jitter frequency multiplier, analysis shows that the jitter performance of the DLL can be jeopardized by the cascading structure of the delay cells. Thus, a new architectural form is proposed. In this design, the delay chain of the conventional DLL is replaced by a polyphase filter (PPF) to generate clock edges for frequency multiplication purposes. A fundamental jitter analysis shows that the random jitter performance of the proposed PPF frequency multiplier outperforms that of the conventional DLL. Because the clock edges generated by the PPF have a larger mismatch when compared to their DLL counterparts, an analog-based phase error calibration (PEC) circuit is proposed to reduce the phase error. In doing so, both the random and deterministic jitter can be minimized and a frequency multiplier with better jitter performance is achieved.
DRNTU::Engineering::Electrical and electronic engineering
Nanyang Technological University