FPGA-Based High-Precision Pulse Signal Detection Unit for Large-Scale Scientific Experiments

With the increasing demand for high-precision time measurements in the field of high-energy physics, Time-to-Digital Converters (TDCs) have become important measurement tools widely used in scientific research such as particle physics and nuclear physics. Traditional TDC implementations usually rely on Application-Specific Integrated Circuits (ASICs), but their high cost and long development cycles have made FPGA-based TDC systems a research focus. This paper presents a high-precision FPGA-based TDC system that combines coarse counting and fine measurement structures. By employing code density testing and bit-by-bit calibration methods, the system significantly enhances time measurement accuracy and stability. The system utilizes the UDP protocol for data transmission and employs a Gigabit Ethernet interface for high-speed data exchange. Experimental results show that the designed TDC system achieves a time resolution of 13.44ps, with low RMS error (17.34ps) and small nonlinear errors (DNL and INL ranges of [-0.99, 1.08] LSB and [-2.27, 2.31] LSB, respectively). This TDC system holds great potential for applications in high-energy physics experiments and particle accelerators, providing high-precision time interval measurement support.