1 Typical Automotive System Architecture

A typical DLP® automotive projector system as shown in Figure 1-1 uses solid state illumination and a DMD controller such as the DLPC120 or DLPC230 for applications similar to head-up display (HUD) or high-resolution headlight. The controller has an input for video data and an output for DMD data, DMD control signals, and illumination control signals. Each frame of video is read by the controller, processed, and converted to a set of DMD native format bit-planes. These bit-planes set the state of the DMD mirrors and cause light to be reflected toward the projection optics or away from the projection optics. Each bit-plane is associated with an illumination color. Each time a bit-plane is loaded and displayed control signals from the DMD controller enable the correct illuminator. As each bit-plane is loaded, the viewer's vision system combines the bit-planes into a single full color video frame.

While this approach provides the maximum flexibility for system design, it also leads to a number of system requirements that may increase system cost and complexity. This type of system requires a video source such as a CPU/GPU combo that generates the video content or loads it from memory. It may also require a host microcontroller to bring up and configure the DMD controller. The DMD controller itself also requires RAM for either an external or internal frame buffer depending on the controller architecture. If space is a concern then the host processor and GPU may need be located remotely. This requires that a high-speed video bus be added to the system which may include serializers/deserializers along with specialized cables and connectors. While all of this is appropriate where you have a system critical display that requires constantly updated information from the ADAS system such as a HUD, it may not be appropriate for dynamic ground projection displays where only a limited subset of information needs to be displayed for a short period of time.

Figure 1-1 HUD Simplified Schematic