Print Email Facebook Twitter Time-to-Digital Converter for Low-Power Direct Time-of-Flight System Title Time-to-Digital Converter for Low-Power Direct Time-of-Flight System Author Xu, Guo (TU Delft Electrical Engineering, Mathematics and Computer Science) Contributor Du, S. (mentor) Nihtianova, S. (graduation committee) Gao, C. (graduation committee) Degree granting institution Delft University of Technology Programme Electrical Engineering | Microelectronics Date 2022-09-29 Abstract Depth sensing technology has developed rapidly recently due to its broad applications. Time-of-Flight (ToF) is a popular technology in depth sensing because of its advantages in high measuring accuracy and low complexity in image processing. ToF technologies are divided into two kinds: indirect time-of-flight (iToF) and direct Time-of-Flight (dToF). Compared to the iToF, dToF can detect targets at a longer distance by directly calculating the flight time of the laser. To obtain time information, the dToF system requires a Time-to-Digital Converter (TDC). This thesis proposes a system-level model to optimize the TDC parameters for a dToF system used in an autofocus system of a mobile phone. According to the simulation result of the system modeling, a ring-based TDC is chosen and built using a shared and duty-cycled Voltage-Controlled Oscillator (VCO). To decrease the DNL of the TDC, chopping comparators are used in this design. In addition, to save power and area, a new method called double sampling is used to align the coarse and fine phases of the ring based TDC. The proposed TDC achieves a resolution of 100 ps and a DNL of −0.27/+0.37 and an average power of 0.179 mW/TDC, which are smaller than that of state-of-the-art TDCs used in dToF systems. SMIC 55BSC technology is used to design and tape out the TDC. Subject dToFRing-based TDCLow powerSmall DNLChoppingDouble sampling To reference this document use: http://resolver.tudelft.nl/uuid:e2fffc73-2684-454d-bbce-4ea442008cf2 Embargo date 2023-09-29 Part of collection Student theses Document type master thesis Rights © 2022 Guo Xu Files PDF Guo_Xu_master_thesis.pdf 4.46 MB Close viewer /islandora/object/uuid:e2fffc73-2684-454d-bbce-4ea442008cf2/datastream/OBJ/view