The design of time marker generator

Abstract

This paper mainly introduces a design of time marker which based on the DDWS principle. The time marker signals to include square waveform, plus waveform, narrow triangular waveform and liner triangular waveform. The first core task is to generate these waveforms. In order to achieve this, the relationship between storage size and waveform feature was analyzed. An address generator structure was proposed. By this structure, the time marker signal was generated by using FPGA's inner memory resource. Keep the synchronization output signal and time marker signal precise synchronization is the second core task of time marker generator. Firstly, some influence factors of synchronization are analyzed, and some synchronization methods are proved. The test result shows that this time marker generator could output 111MHz square waveform, the highest frequency resolution could lower than 1mHz. The rising time of square waveform is lower than 1ns and the time marker and synchronization output signal are precise synchronization. We also designed the high light mode, which could let the oscilloscope calibration more convenient.