Issue link: https://iconnect007.uberflip.com/i/1467185
MAY 2022 I DESIGN007 MAGAZINE 25 driver of a Spartan 6 FPGA, an 18.7 Ω series resistor is required to match the driver to the 51.67 Ω trace on the outer layer. is is auto- matically derived from the IV curves of the Spartan 6 IBIS model by the iCD Termination Planner (Figure 4). Figure 4: Matching the Spartan 6 driver to the transmission line. (Source: iCD Termination Planner) Figure 3: Unmatched (red) vs. matched (blue) transmission lines.