Vision-based security systems have become almost everywhere in automotive applications. A variety of high-definition displays are quietly appearing in the center console, rear seat backrest, and dashboard to fully meet the needs of infotainment. In addition, car manufacturers are increasingly deploying cameras to improve safety and driver assistance applications (such as improving the visibility of parking and parking). The National Highway Traffic Safety Administration (NHTSA) of the United States has developed new car safety regulations that require all cars to have rear video cameras and displays as standard equipment in 2014. Reversing accidents cause hundreds of deaths and thousands of injuries each year. The ordinance aims to reduce the number of casualties. This will undoubtedly improve safety and enhance the driving experience, but the increase in all these cameras will also bring new challenges to automotive system designers.
Link for high-speed video transmission A dedicated high-speed video link connects each display or camera in the car to the control (head-end) unit. The simplest is to use a single coaxial cable to display the NTSC (CVBS) signal from the rear camera on the screen of the center console. However, the current trend is clearly to use megapixel digital cameras to improve the clarity and quality of the images displayed on high-resolution LCD panels.
A high-speed serial digital link connects the video components and provides seamless connectivity between the camera's digital imager and the digital LCD display. The most common and reliable high-speed digital interface technology deployed in automotive video links is based on the ANSI/TIA/EIA-644-A Low Voltage Differential Signaling (LVDS) standard. LVDS provides a robust data transmission standard that supports long range, low power, high noise immunity, and low EMI. LVDS implements the required link attributes in a differential manner rather than as a single-ended signal referenced by ground.
By reducing the size and weight of the system by deploying smaller connectors and cables (two important features in automotive applications), the cost of interconnection can be reduced. As shown in Figure 1, the serializer receives data from a video source (such as a camera image sensor) and then converts parallel bus signals and control signals of RGB colors into an LVDS serialized data stream for transmission over a single twisted pair cable. Cable transmission. A matching deserializer at the other end of the cable can extend the video signal back to the parallel interface that connects the display or host.
Texas Instruments' FPD-Link III serial string product family offers a variety of advanced features that address the challenges of high-speed system design. A single serial data stream transmitted over a single differential pair can avoid the problem of data delay differences. These devices can encode serial data to include embedded clocks that can be recovered without a reference clock, allowing quick initialization of connections without special training sequences. The carefully randomized and descrambled video data not only minimizes electromagnetic interference (EMI), but also has DC balance, which helps the transmission and recovery of signals over 10 meters long twisted pair or single coaxial cable. . These measures can help reduce EMI, which is very important in the automotive environment and has strict electromagnetic compatibility (EMC) standards.
Crystal Clear Back Sticker,Phone Sticker,Mobile Phone Back Skin,Crystal Clear Phone Skin
Shenzhen Jianjiantong Technology Co., Ltd. , https://www.mct-sz.com