文摘
Accurate generation of picosecond-resolution wide–range time intervals gives rise to a new time-efficient method for the characterization of large arrays of time-to-digital converters involved in time resolved imaging. This paper presents the design and measurement of a time interval generator based on FPGA technology. Although it can be employed in different automatic test setups, it has been designed to characterize an array of time-to-digital converters. It can work as periodic pulse/frequency generator but also as a digital-to-time converter. The accuracy of periodic pulse generator is around 20 ps RMS jitter for a pulse width ranging from 600 ps to 33 µs. The incremental time resolution is 8 ps and the repetition rate is up to 2 MHz. The accuracy of the digital-to-time converter is less than 0.8LSB DNL and 2LSB INL, whilst the time resolution is 27 ps. Full characterization of the module is reported including a comparison with state-of-the-art instruments in this field. The measurement results of the time-to-digital converter array driven by the designed digital-to-time converter module are presented as well. The effectiveness of the proposed method is evaluated by comparing it with the statistical code density test.