Robust and Accurate Measurement Methodology for High-speed Channel Electrical Characterization

Abstract

As communication technology transits to 5G generation, it drives the development of AI ecology, such as new smart factories, smart warehousing, smart real-time monitoring platforms and other applications, which also tests the quality detection capability of high-speed channels in the data center printed circuit board(PCB), such as the loss of high-speed channels capability of measurement and impedance measurement and segmental analysis. The PCB manufacturers usually check the impedance by time-domain reflectometer (TDR) and channel loss of the PCB by vector network analyzer(VNA) according to the IPC standards [1] [2]. It is critical to have multi-zone analysis ability of the TDR impedance profile in the design and manufacture accurate perspective, such as how to identify correctly break out with the narrow trace routing, plating through hole (PTH) via and main routing impedance. In this paper, VNA with the calibration technology is proposed to not only analyze TDR impedance with multi-zones but also measure channel loss for quality risk assessment. The precision coaxial air lines are adopted as primary reference standards to assure impedance measurement verification, and traceability mechanism is conducted into the comparison experimental of impedance compensation capabilities for accurate and robust measurement. [3–5]