2GSa/s Mixed Signal Analyzer Oscilloscope Module Design And Implementation

With the development of times and the progress of science and technology, thecomplexity of test signal in the electronics field is increasing. Test signal has progressedfrom a single digital signal or analog signal to a complex mixed signal containing theabove two kinds of signals. For complex mixed signal, it can not complete the testingtask very well just by ordinary digital storage oscilloscope or simple logic analyzer.Mixed signal analyzer is a kind of comprehensive test device. Its functioncombines analysis of analog signal wave ’s amplitude, frequency of digital storageoscilloscope in time domain and analysis of the signal characteristics of multichannellogic analyzer in data domain.This subject mainly designs the hardware system of oscilloscope module of2GSa/s mixed signal analyzer. Based on the mixed signal oscilloscope hardware system,analog channel circuit, data acquisition, storage and control circuit, and PCI interfacecircuit are mainly designed. The specific content of this paper as follows:1. Determine the design scheme of the whole system. It mainly includes the designof signal conditioning circuit, data acquisition, storage and control circuit design, triggercircuit design and PCI interface circuit design.2. Trigger circuit design is introduced in detail. First of all,this paper focuse on thetrigger signal conditioning circuit design, mainly including the trigger source selectingcircuit, trigger comparison circuit and the trigger threshold level circuit. On the basis ofthe existing trigger pulse width and then focus on how to implement the following fourtypes of trigger in the FPGA internal, namely:TV Trigger,Pulse Width Trigger, OweAmplitude Trigger and Interaction Trigger3. Peak detection circuit design has been discussed in detail. First, this paperintroduces the significance of peak detection, then respectively introduces method oftwo different implementations that is analog peak detection and digital peak detection.By comparison, this subject eventually chooses digital peak detection,and gives adetailed description of it’s realizationAs mixed-signal oscilloscope hardware system design completed, all parts of the circuit and complete machine were debugged and tested. Through continuousimprovement, the final experiment result shows that all indexes and functions fulfill thedesign requirements, and this subject has been basically achieved the expected goal.