Application of FPD-Link II chipset in automobiles
In 2006, National Semiconductor innovatively developed the serial deserializer (SerDer) FPD-Link II chipset series for single-pair twisted pair differential transmission. This serialization scheme eliminates the need for data and clock paths. Skew simplifies the conversion of a 24-bit bus on a single differential pair. The single-pair twisted pair can help reduce the number of PCB layers, cable width, connector size and pins, thereby saving system costs. In the traditional display system design, the graphics controller or graphics processor (GPU) transmits parallel RGB color bits aligned with the pixel clock and synchronization signals. These signals use TTL levels, and there are more than twenty signal lines. In the connection of the LCD display, sometimes the parallel bus cannot exceed 20cm ~ 30cm in length due to the cable is too thick, or the power supply and EMC (electromagnetic compatibility) and other issues. To solve this problem, National Semiconductor developed the serial deserializer (SerDes) FPD-Link (flat panel display-link) chipset series with the industry-leading TFT panel suppliers in the mid-1990s. The transmitter collects up to 18-bit / 24-bit RGB information (6-bit / 8-bit color) and three control signals and clocks, and then converts them into three differential data pairs and one clock pair. The wire pair is reduced to 4 pairs, and LVDS transmission is used to solve the EMC problem. It is the display interface standard of notebook computer \ LCD monitor \ LCD TV. Features of DS90UR241 / 124 The DS90UR241 / 124 chipset is a 5-43MHz DC balanced 24-bit LVDS serializer / parallelizer with 24: 1 and 1:24 data transmission, with user-defined pre-emphasis, supporting AC-coupled data transmission, Embedded clock and data recovery (CDR), power supply voltage 3.3V ± 10%, has a wide range of uses. Main features: a pair of differential twisted pair transmission, simple wiring, low cost; 24-bit data serialization / deserialization (18-bit video + control signal + I2S audio); signal conditioning circuit can extend the transmission to 10 meters, Meet the requirements of long-distance transmission; very low EMI, easy to pass the car test; embedded clock in the data, so that the deserializer does not need a reference clock, reducing system cost; built-in BIST mode (convenient for factory test / online diagnosis) Passed AEC-Q100 level 2 (vehicle-level certification qualification). Application of DS90UR241 / DS90UR124 in automobile display system The application of the car display system includes: the display of the center console, the headrest display of the back seat, the display of the car instrument, and the display of the navigation system. Others such as: head-up display system, rear view display system, camera system / sensor system / other assisted driving system. The general WVGA format display adopts 800 × 480 WVGA resolution, 18 bits (color depth, RGB666 format), and the clock frequency is about 30MHz. Electrostatic Precipitator Transformer Electrostatic precipitator transformer, silicon rectifier transformer, high-voltage electrostatic precipitator rectifier transformer, high impedance transformer Henan New Electric Power Co.,Ltd. , https://www.newelectricpower.com
Figure 1: FPD-Link II DS90UR241 / 124 functional block diagram.
Figure 2: FPD-Link II display signal switching application (crossbar switch).