Analysis And Application Of USB3.0High-Speed Signal Integrity

With the increase of clock frequency and edge rates in high-speed digital systems,^he signal experience delay, reflection, attenuation, crosstalk, dispersion in high-speed interconnect, which get more critical and become domain in signal integrity design. The signal integrity problems are electro-magnetic (EM) problems in nature. USB3.0which is the third major revision of the Universal Serial Bus (USB) standard for computer connectivity was published in2008. Its transmission speed is up to5Gbps, which is10times faster than USB2.0(480Mbps). So, signal integrity is the key factor in USB3.0circuit design.Firstly, in this thesis the characteristic of USB is introduced and the similarities and differences between USB3.0and USB2.0are compared and summarized. The architecture and data transmission of USB3.0is showed and the test items of USB3.0are discussed. Then the problems of signal integrity and analysis method are studied and the mixed-mode s-parameters expression of differential circuit with different topology is present, and applied to the signal integrity analysis of high-speed differential interconnect system. Next, EM modeling and simulation are discussed, HFSS simulation software is applied to analysis how the test points and holes on single-ended or differential transmission line is effected the transmission of USB3.0signal. Then design guidelines for improved signal integrity are derived from the results obtained. Thereby, the design of high-speed circuits can be guided to solve signal integrity issues. Finally, the circuit design, placement and routing, simulation and analysis of USB3.0in PCB level are done on the basis of the simulation results, the USB3.0signal of real main board is tested.The design guidelines present in this thesis works efficiently to improve the high-speed signal integrity, and had been applied to the design of SATA3.0.