2 Typical Local Dimming System

Figure 2-1 is a typical infotainment local dimming system block diagram, which is comprised of a system board and an LED backlight board.

• The system board usually has a de-serializer, TCON (timing-controller), microcontroller (MCU), and some power supply circuits. The de-serializer receives video signal from a serializer on a cockpit or head unit through FPD-Link™, then transfers this signal to the TCON. The TCON accepts the image data stream, calculates and outputs the brightness data for each backlight zone. The MCU, usually used for power management, accepts the temperature sensor signal.
• The LED board usually has LED drivers, LED matrix, and temperature sensors. The system board and LED board are connected off-board using FFC cables.

Figure 2-1 shows each block that should meet functional safety standards. Let’s discuss how the LED power and the light-emitting diode (LED) backlighting driver can be designed for ASIL-B compliance.