Issue link: https://iconnect007.uberflip.com/i/1126810
JUNE 2019 I DESIGN007 MAGAZINE 67 Once the dielectric material has been select- ed, one needs to plan the most efficient stackup configuration for the design. For a typical digital design, 40–60 ohms impedance is recommend- ed. However, numerous impedances are gener- ally required to convey differential pairs of var- ious technologies. Therefore, all combinations of impedances must be defined on the one sub- strate. Figure 4 shows three differential technol- ogies defined on the same stackup layer. Now that the stackup is finalized, let's look at impedance matching the source to the trans- Figure 3: Loss profile for ultra-low-loss dielectric materials. (Source: iCD Materials Planner) Figure 4: Unlimited differential technologies can be defined on the same layer. (Source: iCD Stackup Planner)