| In section 1, the procedures of 1X-Reflect smart fixture de-embedding (SFD), 1-port auto fixture removal (AFR), and 2X-Thru SFD are compared from various perspectives: test fixture design, the de-embedding procedure, and de-embedded results. The accuracy of fixture characterization and the de-embedded result is the key figure of merit (FOM) in each de-embedding method. Full wave models are built to evaluate the FOM of the three methods, by comparing the scattering parameters (S-parameters) and time domain reflectometer (TDR). A test coupon for measuring USB-C cables is adopted to serve as a manufactured validation purpose.;In section 2, a physics-based circuit model for a novel differential probe without a nearby ground pin is built up to 20GHz. First, the SFD method is used to obtain the S-parameter of a differential probe in a full wave model to validate the effectiveness of this method. Second, real measurements are made to obtain the S-parameter of a differential probe. Furthermore, the one-to-one corresponding circuit model has been built to understand the physics of probes. A layout for the advance interconnect tool (AITT) demo board is then designed to test probe characteristics and AITT software. Finally, the SFD method is applied to de-embed the test fixtures, and material information is extracted based on the de-embedded results. |
