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Access Type

Campus Access

Document Type


Degree Program

Electrical & Computer Engineering

Degree Type

Master of Science (M.S.)

Year Degree Awarded


Month Degree Awarded



Digital-to-Time Converter, Time-to-Digital Converter, Fluorescence Lifetime Imaging


This thesis presents time difference (TD) circuits that are important for measuring fluorescence lifetime, building LIDAR systems, and optimizing digital systems. The contribution of this thesis is to present a systematic organization of TD circuits and to present novel designs for digital-to-time conversion (DTC) and time-to-digital conversion (TDC).

Four basic time difference circuits are presented: TD adder, arbiter, time-difference MUX, and time-difference memory. Specifications, symbols, and multiple circuit implementations are presented for each block. Then the basic blocks are combined to form two compound blocks: DTC and TDC. Novel designs are presented for both blocks along with detailed simulation results.

The DTC was fabricated in TSMC’s 0.35um high-voltage process. A printed circuit board was designed to interface the DTC chip to a computer and test instruments. The DTC demonstrated 80ps resolution.


First Advisor

Christopher Salthouse