The MT3729 is an 800GbE (Dual 400GbE) MACsec Retimer PHY (16-lane bi-directional PHY device with 56G PAM4 or 28G NRZ Serdes) for applications such as Data Center switch SoC to Retimer companion chip. MT3729 can be used in line cards or switch fabrics in conjunction with network controller ASICs to build multi-terabit network servers, switches, and routers.

The MT3729 is available as a standard product or in a semi-custom ASIC design.


Key Features

  • Retimer Mode: signal reinforcement that extends the SerDes connection distance and transmission to the edge.
  • Forward/Reverse GearBox Mode: bitrate translation between 56G and 28G links without replacing the facility during the transition.
  • MUX/DeMUX Mode as a redundancy requirement for hitless MUX and Broadcast.
  • IEEE 802.1AE MACSec for secure communications with AES128/256 encryption from 1G to 400GbE per port and highly accurate PTP timestamping.

Product Highlights

  • Up to 800GbE throughput (Dual 400GbE)
  • IEEE standards compliance for 400GbE, 200GGbE, 100GbE, 50GbE, 40GbE, 25GbE, 10GbE, and 1GbE
  • Support for 400GAUI-8 electrical interfaces for QSFP-DD & OSFP optical modules
  • 16 bi-directional links at 56G PAM4, up to 28G NRZ SerDes and 1G SGMII options
  • PCS with various FEC modes to support FEC termination and regeneration.
  • Support for IEEE 1588v2 and SyncE up to Class-C to meet stringent 5G infrastructure timing requirements to provide more flexibility and accuracy
  • Support flexible 1588 operation modes
    • 1588 @ Host Switch (latency fixed @ PHY)
    • 1588 @ Host Switch and PHY (to automatically add PHY latency to PTP event packets)
    • 1588 @ PHY