Hardening of serial communication protocols for potentially critical systems in automotive applications: LIN bus

Serial communications protocols used in automotive systems must comply with different levels of robustness. Some subsystems in charge of n on-critical tasks are composed of cheaper and non-fault tolerant elements. As Single Event Upsets also affect these sub-systems, a complete analysis of heir robustness could highlight the critical elements and point out the possible solutions, such as selective hardening in a cost effective way. An extensive fault injection campaign has been applied to a LIN bus controller module in order to select the best mitigation techniques to harden it against soft errors. A discussion around how these mitigation techniques could affect on-line testing in the module is also presented.