Integrated LCD controller technology improves vehicle safety
The TW8836 can be used to display rear camera video with graphic overlay in less than 500 milliseconds from the start of a vehicle, exceeding government safety regulations. This device can be used in a wide array of infotainment system applications and is optimised for use with today’s most popular SoCs.
All new light vehicles sold in the USA have to have the ability to display rear camera video within two seconds from the time that the vehicle is put in the reverse gear. Many experts anticipate that other regions around the world will follow suit by implementing similar laws.
The TW8836 is designed to sync to a composite video source, scale and de-interlace the video, and display the image on the LCD panel in less than 500 msec, far exceeding the fast boot requirements outlined in the new U.S. law. Because the TW8836 does not require any external memory, the video is latency free and thus ultra responsive to help increase the backup safety of vehicles. Since the TW8366 is a hardware-based solution, many automotive manufacturers view the LCD video processor as more reliable in terms of fast boot capability and as a more stable video path for the rear camera than competing software-based solutions supported by the main processor. Because the main processors require time for the operating system (OS) to boot up, there is risk to routing the rear camera video through SoCs as any glitch in the software could compromise the reliability and integrity of the backup camera video.
The TW8836 provides a special BT.656 output path that is independent of the primary LCD scaler path, enabling ultimate system architecture flexibility—the chip can drive the panel directly and show rear camera video while the SoC is booting up. Once the SoC boots up, it can then route the source video to the SoC via the BT.656 path to support overlay of graphics (GUI) on top of the video. The combined video can then be sent back to the TW8836 for display on the LCD via the Open LDI (LVDS) or digital RGB input port. Such features allow the TW8836 to be used in conjunction with the most popular infotainment SoCs in the market.
The TW8836 LCD video processor can take virtually any type of video input—including analogue composite, S-video, analog RGB, digital RGB and Open LDI (LVDS)—and drive almost any digital LCD panel up to WXGA+ (1366 x 768) resolution—including transistor-transistor logic (TTL), 1 CH Open LDI (LVDS) and timing controller-less (TCON-less) panels—making it a suitable solution for rear camera display or multiple video source infotainment applications. TW8836 can be used by automotive OEMs to support a wider variety of both analogue and digital video sources, as well as offload the video processing workload from the main processor, allowing the processor to support additional system functionality or the manufacturer may simply use a lower cost processor.
The TW8836 helps optimize the system design and overall cost as it supports differential composite inputs, eliminating the need for an external op amp. In addition, the device does not need external DRAM, helping to keep the bill of material (BOM) cost of implementing the LCD video processor relatively low.
Intersil; www.intersil.com/products/TW8836