AbstractsComputer Science

A pipelined metastability-independent time-to-voltage converter with adjustable resolution

by Dong An




Institution: McGill University
Department: Department of Electrical and Computer Engineering.
Degree: M. Eng.
Year: 2007
Keywords: Signal processing  – Digital techniques  – Computer simulation.; Integrated circuits  – Very large scale integration  – Computer simulation.
Record ID: 1811166
Full text PDF: http://digitool.library.mcgill.ca/thesisfile112554.pdf


Abstract

As modern integrated-circuit (IC) technology advances, the level of integration increases, and so too does the clock speed of on-chip signals. As a result, signal integrity has become a major issue on which the circuit performance is largely based. Clock jitter is one of the main issues of signal integrity, and it has become one of the most important circuit limitations. While extensive research is on-going to reduce clock jitter in ICs, researchers have also been actively involved in discovering ways to characterize it through applications of new time measurement units, or TMUs for short. A number of TMUs have been designed with resolutions down to the picosecond range, among which the time-to-voltage converter (TVC) is a very popular family of circuits used for making highly precise and accurate time measurements. These circuits are popular due to their excellent linearity properties and their ease of fabrication. Nonetheless, these circuits suffer from metastability issues, limiting the lower end of their measurement range. This thesis first reviews the past TMU circuits, and then presents a TVC architecture that solves the metastability problem. In addition, pipelined operation is added to further increase the throughput of the design. The resolution of the TVC is made adjustable such that it can be used as a stand-alone TMU for different types of applications. The proposed TVC is both verified in simulation and experimentally using a custom designed circuit in a standard 0.18 microm CMOS process supplied by TSMC. Finally, a calibration method is included to further improve the linearity of the overall design.