Vehicle cabins are increasingly equipped with multiple displays, facilitating operation for different occupants and enhancing the overall riding experience. For example, next-generation instrument clusters, HUDs, center information displays, rear-seat entertainment screens, etc. Instrument Cluster and HUD: The DSS subsystem renders the fused environmental model (e.g., vehicle trajectories, obstacle annotations) within the driver's field of view, ensuring low-latency presentation of critical information. Center Display and Rear-Seat Entertainment: GPU acceleration enables 3D rendering of navigation interfaces and video content, supporting either independent display on multiple screens or synchronized content (e.g., rear passengers controlling the center console menu). In the event of a camera or display failure, the system automatically switches to a redundant signal source or a simplified interface to ensure that basic driving functions remain unaffected.

In automotive processing, display interfaces such as DPI, DP, OLDI, or DSI are widely used. These different interface technologies effectively enable a variety of display solutions. Table 4 lists commonly used SerDes solutions for automotive display applications.

• DPI: Supports RGB interfaces as well as YUV image formats such as BT565/BT601. As a relatively basic interface, it has limited transmission distance and weaker immunity to interference, making it more suitable for small-sized screens. Recommended FPD-Link solution: Serializer DS90UB925-Q1, Deserializer DS90UB926-Q1.
• OLDI/LVDS: Encodes high-speed signals into differential signals for transmission, significantly improving immunity to interference and supporting larger screen sizes and higher resolutions. Recommended FPD-Link solution: Serializer DS90UB947-Q1, Deserializer DS90UB948-Q1.
• DSI: Developed by the MIPI Alliance, it also uses low-voltage differential signaling at the physical layer, similar to LVDS, but with a more complex protocol. DSI can switch between high-speed and low-power modes during video transmission to reduce power consumption. Both SoCs and FPD-Link devices support DSI single-link and dual-link configurations. Recommended FPD-Link solutions: Serializer DS90UB941AS-Q1 with Deserializer DS90UB948-Q1; or Serializer DS90UB981 with Deserializer DS90UB988-Q1 (supports superframe).
• DP: Developed by the VESA association, this interface is currently the mainstream choice and future direction for high-resolution automotive displays. DP supports higher bandwidth, enabling 4K or even 8K resolution with high refresh rates. Additionally, DP supports MST technology, facilitating multi-video transmission. Recommended FPD-Link solution: Serializer DS90UB983AS-Q1, Deserializer DS90UB984-Q1.

In SerDes-based display applications, several technologies (Superframe, Daisy-Chain, MST, etc.) are employed. By combining these technologies, a wide variety of multi-display solutions can be conveniently implemented.

• Daisy-Chain: Modern vehicles, particularly new energy and premium models, are typically equipped with multiple screens. In such multi-display systems, daisy-chaining plays a critical role. Daisy-chain topology allows a single SoC interface to drive multiple displays or audio processing modules. It also resolves the issue of complex, heavy, and expensive wiring that would otherwise result from connecting each display to the host with independent cables. The topology is illustrated in Figure 2-2.

• MST: Supported in DP 1.2 and higher interface protocols, MST enables simultaneous transmission of video streams with different resolutions, color depths, and frame rates. It offers high transmission efficiency and stability, and can be used in conjunction with daisy-chaining.
• Superframe: Apart from the MST functionality of the DP interface, Superframe is another common method for multi-video transmission. By leveraging the SoC's video processing capabilities, video streams of different resolutions are combined into a standard rectangular video stream by inserting vertical blanking intervals between them. The combined stream is then transmitted, and the internal video processor within the serializer restores the individual video streams for output to each display. This approach enables the transmission of a greater number of video streams using fewer SoC video interfaces.