PCI Express* 4.0 Retimer Supplemental Features and Standard BGA Footprint
PCI Express* 4.0 capable retimers extend the channel reach on a platform to beyond what is possible otherwise.
With PCI Express* 4.0 (16 GT/s), data rate has increased by 2x compared to previous generation (8 GT/s), resulting in shorter channel reach. Common use cases include channels expanding over system boards, backplanes, cables, risers, and add-in cards. Such long channels can have loss that far exceeds the spec loss target of -28 dB at 8 GHz. Retimer is now part of PCI Express* 4.0 base specification. PCI-SIG is expected to implement compliance program for testing retimers.
It is expected that significant number of platforms using PCI Express* 4.0 will require retimers. Multiple sources of retimers will make adoption of PCIe* 4.0 technology easier. Common footprint simplifies the platform design process. Pinout is optimized for 16 GT/s signal integrity and thermal challenges.