Issue link: https://resources.mouser.com/i/1437732
32 Circuit Protection for High-Speed Serial Interfaces Protecting the ADAS The signal processing, communication, and control subsystem operate the vehicle. This main subsystem must be robust, reliable, and fail-safe. The circuit must react to other vehicles in traffic and make fast stops when an animal or person obstructs the vehicle's path. The subsystem also must have a fail-safe response to a failed sensor. All circuit blocks that supply information to the controller need protection from ESD. Like the other power-supply blocks, the ADAS power supply (Figure 4) requires over-current protection, surge protection, and reverse polarity protection. The fuse for this supply can reside within the module or further upstream in the vehicle's low-voltage junction box. A TVS diode, picked for its surge power rating, protects against surge transients. A Schottky diode in series with the power supply input line provides reverse voltage polarity protection. Each communication link requires ESD and transient protection designed for each port's performance and configuration. Design engineers can select from a wide range of diode arrays and polymer ESD suppressors to protect each communication link without compromising its data rate or its high-to-low voltage differential. Any signal lines connecting directly to the DSP circuit block should have ESD and transient protection. Designers can use diode arrays or polymer ESD suppressors that provide bipolar protection for high and low signal lines. The ADAS communication and control subsystem is the primary intelligence for autonomous vehicles. This subsystem must remain operational at all times. ESD protection on all ADAS inputs and outputs will protect the subsystem from disabling ESD strikes, and TVS diodes will protect against surge transients generated by electric and electromechanical devices. Figure 4: The ADAS power supply requires over-current protection, surge protection, and reverse polarity protection. (Source: Littelfuse)