Dielectric Loss Tangent Extraction Using Two Single-ended Striplines of Different Width

Frequency-dependent electrical properties of dielectric materials are one of the most important factors for high-speed signal integrity design. Recently a method of accurately measuring the dielectric loss tangent (
$\tan \delta$
) of differential lines was proposed. By taking into account the ratio between the differential and common mode per-unit-length resistances the surface roughness contribution to the total loss is eliminated and dielectric parameters can be determined. In this article a similar method is applied to a combination of two single-ended lines. To evaluate the accuracy of the extraction, the impact of the de-embedding errors was investigated, which allows to optimize the test PCB design. The extraction method was validated in measurement using a PCB with several two-width pairs of strip lines. The extracted loss tangent of several optimal two width pairs of single-ended lines is validated by the SPDR measurements.