Support for DisplayPort 2.0 in USB4 PHYs
DisplayPort 2.0 traffic is not tunneled over USB4 or Thunderbolt because the USB4 specification only defines DisplayPort 1.4a tunneling. Synopsys USB4 PHYs support DisplayPort 1.4 TX Alternate Mode and can optionally be customized to support DisplayPort 2.0 TX according to the newly announced DisplayPort 2.0 Alternate Mode specification. When customized to support DisplayPort 2.0 TX, Synopsys’ USB4 PHY supports UHBR10, UHBR13.5 and UHBR20 data rates. Four lanes of UHBR20 provide 80 Gbps raw data rate, capable of supporting 8K or even 16k monitors and TVs, high refresh rate gaming, advanced AR/VR, and other advanced display applications.
USB4 Device Router for AI Acceleration
Synopsys offers DesignWare® USB4 Device Router IP, initially targeting (Artificial Intelligence) AI accelerators for edge and mass storage applications. How each AI accelerator functions with associated local compute and memory is dependent on the specific implementation, but one possible example is shown in Figure 3. In USB4 mode, this AI accelerator uses USB4 to connect to a PCIe 4.0 embedded endpoint using tunneled PCIe. This mode enables the AI accelerator to take advantage of a low latency direct memory access (DMA) connection to the host system memory. In USB 3.x mode, this AI accelerator connects to the USB host using either legacy USB streaming (isochronous) or bulk traffic. Figure 3 also shows a customized USB4 PHY that supports PCIe 4.0. Integrating a customized USB4 PHY allows the AI accelerator to be mounted on a PCB in an embedded host or mounted on a PCIe expansion card.