A passive serial channel test circuit board for VPX bus

Abstract

The invention discloses a passive serial channel test circuit board for VPX bus, comprising two VPX test daughter card circuit boards and a VPX test backplane circuit board; calibration and influencing factors are set on the VPX test daughter card circuit board Test area and VPX daughter card simulation test area; VPX backplane simulation test area and calibration and glass fiber effect test area are set on the VPX test backplane circuit board. The invention discloses a set of test circuit boards for the VPX test daughter card and the VPX test backplane, which can measure the influence of a single key factor on the performance index, and can realize the simulation test of the VPX passive serial channel and the synthesis of the PCB design performance. Evaluate, guide the design and optimization of VPX products, and reduce product design costs. The test board can simulate various PCB design schemes of passive serial channel in VPX daughter card and VPX backplane, and can realize the simulation test of passive serial channel of VPX bus. Comprehensive integration of key factors such as calibration circuit and pad, via stub, glass fiber effect, transmission line loss, etc., can complete the test evaluation of various key factors.

Description

technical field [0001] The invention relates to a passive serial channel test circuit board of a VPX bus. Background technique [0002] The performance of modern electronic products and the integration of the system are getting higher and higher, and the application of high-speed serial bus has become the mainstream. With the increase of the serial bus rate, the traditional PCB routing has shown the characteristics of the transmission line. The pads, via stubs in the PCB design, and the glass fiber effect of the board will cause the impedance of the transmission line to be discontinuous and affect the serial channel. Insertion loss, return loss and other performances bring signal integrity issues, which become the key factors in the design of passive serial channels. [0003] 1. It is impossible to test and evaluate the impact of key factors in the VPX serial channel on performance indicators [0004] As a new generation of industrial bus standard, VPX bus has been widely ...

AI Technical Summary

Problems solved by technology

With the increase of the serial bus rate, the traditional PCB routing has shown the characteristics of the transmission line. The pads, via stubs in the PCB design, and the glass fiber effect of the board will cause the impedance of the transmission line to be discontinuous and affect the serial channel. Insertion loss, return loss and other performance, bring signal integrity issues, become the key factor in passive serial channel design

[0003] 1. It is impossible to test and evaluate the impact of key factors in the VPX serial channel on performance indicators

[0004] As a new generation of industrial bus standard, VPX bus has been widely used in the field of industrial and military electronics. However, there is currently no test and evaluation method for various key factors of the VPX bus serial channel, and it is impossible to evaluate the performance indicators of key factors in the design. accurate assessment of the impact

[0005] 2. The simulation test of the passive serial channel of the VPX bus cannot be realized

[0006] The traditional test method can only measure the S parameters of the existing VPX backplane. Since there is no complete set of test boards for the VPX test daughter card and the VPX test backplane, it is impossible to design various PCBs that may appear in the passive serial channel of the VPX bus. Therefore, the combination of PCB design schemes that meet the requirements of the serial channel cannot be obtained, and the design cannot be accurately guided, resulting in over-design or under-design phenomenon from time to time

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