Mixed Oscilloscope 5GSPS Logic Analysis And Trigger Module Design

In most test applications,the measured signal may not only be a single digital signal or analog signal,but also contain multiple analog signals and digital signals,and there is a correlation between the two signals.Digital storage oscilloscope and logic analyzer can not meet this test requirement well,so mixed signal oscilloscope came into being.Hybrid signal oscilloscope is a kind of hybrid testing instrument which combines all measuring functions of digital storage oscilloscope with some measuring functions of logic analyzer.This paper will study and design the logic analysis and trigger module of mixed signal oscilloscope.The main work involved is as follows:1.According to the function and index of oscilloscope module and logic analysis module,the model of key components of logic analysis module is determined,and the scheme of trigger system is designed.Finally,the overall scheme of the system is determined.2.Complete the hardware design of logic analysis module in hybrid oscilloscope,including logic probe,signal digitization,5GSPS signal reception,data extraction,triggering and storage based on GTX of FPGA.3.Complete the advanced trigger module of hybrid oscilloscope,realize trigger mode such as edge and then edge trigger,code trigger,Hamming distance trigger,and establish hold time trigger.4.Digital edge triggering method is used to improve the triggering accuracy of oscilloscope edge triggering.The main indicators of logic analysis module are:number of channel 16,bandwidth 400 MHz,sampling rate 5GSPS,storage depth 256 Mpts,inter-channel delay less than 1 ns,probe input impedance 100k?/8pF.The trigger types in the trigger module are: edge,pulse width,slope,edge back edge,Hamming distance,window,under-amplitude,code,state,setting up hold time trigger.The main parameters are as follows: the trigger precision of edge trigger is 0.8ns,and that of other advanced triggers is 3.2ns.