62.5 ps LSB resolution multiphase clock Time to Digital Converter (TDC) implemented on FPGA

Abstract

A 13-bit Time to Digital Converter is implemented using multiphase clock technique. Xilinx’s Virtex 5 FPGA platform is used to realize the TDC architecture. One PLL within the FPGA works as a clock synthesizer to multiply the reference clock to 500 MHz. Then the combination of PLL and DLL topologies are used to generate 16 phases of the clock, separated by 11.25°. Further, 16 phases are generated by inverting the first 16 phases. A resolution of 62.5 ps has been recorded. Measured INL and DNL are within 1 LSB. The present work is suitable for many critical applications due to its PVT insensitive and robust properties.