Research And Implementation Of Patterned Jitter Control Technology

Because the current serial data standard requires a lot of jitter consistency tests.Conformance testing is used to evaluate the signal quality of each device.Through the conformance testing of the product,in addition to understanding whether the product meets the standard specification,it is also possible to quantify the margin of each signal's distance from the Conformance Test Specification(CTS).If the margin is sufficient,it means that the product can be cost-designed.Therefore,understanding timing jitter has become an integral part of the design of high-speed communication systems,and the output of data in serial systems requires low output jitter and can be injected into the specified level of intentional jitter as part of the test process during testing.Based on the above requirements,this paper mainly studies the following aspects:1.Synthesis of pulse signals and the technical study of high-precision,wide-range pulse width coverageThis paper fully applies the signal delay technology and high-speed D flip-flops to realize pulse signals with precise controllable delay and pulse width.In order to achieve accurate and wide range of pulse width and delay control,this paper will introduce a variety of signal delay technology in detail,focusing on FPGA internal delay circuit,count delay circuit and FPGA external programmable delay line implementation delay.Fine adjustment.2.The study of the mathematical model of jitterThe different sources of different types of jitter are analyzed,and then the mathematical characteristics of different types of jitter are studied.Based on this,the corresponding mathematical model of jitter is established.It provides a theoretical basis for the injection of diversified jitter.3.The study of jitter waveform parametersSample points were extracted from four types of jitters: triangular wave,sine wave,square wave,and Gaussian noise.The relationship between the frequency accuracy of the jitter injection signal and the sampling point and DAC sampling rate is studied.4.Research on jitter data loadingStudy how to inject the quantized waveform data into the data signal loading technology;study the data normalization processing technology of the jitter data and programmable delay line control data conversion.5.Technology for Jitter Injection Using High Accuracy Programmable Delay LinesBased on the principle of designing the rising edge jitter injection and falling edge injection,the process of rising edge jitter injection and falling edge jitter injection and its timing control are studied.The rising edge jitter is achieved by precise control of a programmable delay line.Falling edge jitter injection.