3.2.1 Rx Insertion Loss

Receiver insertion loss is used to match the PCB qualities of the system. The predefined settings are used to statically adjust the receiver CDR and DFE. The CDR and DFE parameters are assigned based on a targeted data rate and backplane model. CDR uses only the CTLE capabilities of the PMA receiver. The DFE uses combination of CTLE with DFE optimizations. To start the transceiver design, select the Rx Insertion loss values in Libero. Libero adjusts to the best known setting based on the data rate. If the pre-defined settings do not achieve the best performance, users can fine-tune the Rx CTLE settings to precisely match their system requirements after initial system bring-up.

Backplane or PCB Length, that is, Reach definitions are based upon number of connectors and overall insertion loss as per the CEI-11G SR, MR and LR specifications defined by Tyco Electronics Z-Pack Tinman testing platform. See Transceivers Insertion Loss.

See AC483: PolarFire FPGA Transceiver Signal Integrity Application Note for information about the data rate range and models of backplane length.