Aiming at the problems of integration,cost and power consumption of ADC sampling,a multi-channel high-speed sampling method based on TDC is proposed in the paper.The sampling accuracy is not limited by the ADC sampling bit width,but only related to the hardware parameters and software design of the FPGA chip used.The number of sampling channels is only related to the number of configurable LVDS ports and the size of FPGA chip resources.Different from the traditional ADC sampling method,the first step is to design the acquisition circuit,use the known continuous threshold signal as the comparator threshold voltage,and TDC records the signal to obtain the sampling point when it crosses the threshold time.Secondly,the influence of threshold signal and comparator on the sampled signal is investigated,and the error of each influencing factor is counted to find the optimal solution.Finally,the sampling rule is summarized,and its applicability is analyzed.
Key words
ADC /
TDC /
continuous threshold /
multi-channel high-speed acquisition
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