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The automotive industry is moving from fossil carburant to electric drive trains due to the stringent CO2 reduction policies. In this context, the electric energy storage becomes one of the key parameters of successful rolling out electrified vehicles. Typical battery management systems comprises of battery cells measurement and monitoring, balancing function, temperature monitoring, together with the State of Charge and State of Health estimations based on the given measurements. Together with the functions above, a robust internal IC communication protocol is one of the key parameters to guarantee battery performance as well as safety. This paper focuses on the automotive battery communication system. On one side, the importance of the communication system and its impact in the EDT (electric drive train) is discussed including safety aspects. Later on, the different communication methods up to date are analyzed to further understand their limitations.

In this paper, we propose a hardware and a software design method considering functional safety for an electro-mechanical brake (EMB) control system which is used as a brake actuator in a brake-by-wire (BBW) system. A BBW system is usually composed of electro-mechanical calipers, a pedal simulator, and a control system. This simple by-wire structure eliminates the majority of bulky hydraulic brake devices such as boosters and master cylinders. The other benefit of a BBW system is its direct and independent response; this leads to enhanced controllability, thus resulting in not only improved basic braking performance but also considerably easier cooperative regenerative braking in hybrid, fuel-cell, and electric cars. The importance of a functional safety based approach to EMB electronic control unit (ECU) design has been emphasized because of its safety critical functions, which are executed with the aid of many electric actuators, sensors, and application software.

With the introduction of the ISO26262 automotive safety standard there is a burden of proof to show that the processing elements in embedded microcontroller hardware are capable of supporting a certain diagnostic coverage level, depending on the required Automotive Safety Integrity Level (ASIL). The current mechanisms used to provide actual metrics of the Built-in Self Tests (BIST) and Lock Step comparators use Register Transfer Level (RTL) simulations of the internal processing elements which force faults into individual nodes of the design and collect diagnostic coverage results. Although this mechanism is robust, it can only be performed by semiconductor suppliers and is costly. This paper describes a new solution whereby the microcontroller is synthesized into a large Field Programmable Gate Array (FPGA) with a test controller on the outside.

As the automotive industry quickly moves towards hybridized and electrified vehicles, the optimal integration of power electronics in these vehicles will have a significant impact not only on the cost, performance, reliability, and durability; but ultimately on customer acceptance and market success of these technologies. If properly executed with the right cost, performance, reliability and durability, then both the industry and the consumer will benefit. It is because of these interdependencies that the pace and scale of success, will hinge on effective collaboration. This collaboration will be built around the convergence of automotive and industrial technology. Where real time embedded controls mixes with high power and voltage levels. The industry has already seen several successful collaborations adapting power electronics to the automotive space in target vehicles.

Today's body and convenience applications in general directly control actuators and sensors from a single central electronic control unit (ECU). Future systems will be made of subsystem-clusters communicating via a local Class/A communication bus. This enables modular system design to reduce system complexity. For these types of new distributed applications the LIN bus is currently the most promising communication protocol. To allow a seamless migration from existing centralized to these next generation clustered system developers require software and hardware products for a homogenous and transparent LIN bus communication.

Today's requirements for engine management controllers are increasing in various aspects. Stronger emission standards and diagnosis requirements demand more complex control algorithms, faster system response times, better usage of sensor information throughout the system and higher accuracy of actuator stimuli. Despite that, new solutions are needed to answer the requirement for higher cost effectiveness, flexibility and reusability. The trade-off between cost and functionality is constantly being reviewed when choosing the right microcontroller to operate with an ECU. Integration of more complex and flexible functionality into the microcontroller helps to reduce the need for custom ASICs and thus reduce the overall system cost. In order to reduce the demands on CPU throughput within the microcontroller, manufacturers have introduced smart peripherals that off-load some of the work of the CPU into the peripherals.

Recent trends in field bus applications, especially in the automotive section, show a very high demand for data exchange between decentralised, intelligent functional units and modules. These functional units can be grouped together to power train applications or body/convenience applications. In many cases, the coupling of local modules is done with one or more independent bus systems. The actual design and the partitioning of the modules strongly depend on application-specific requirements, such as the total amount of data to be transferred or the maximum of the tolerated latency in data delivery. A very powerful and fast field bus is the CAN bus (Controller Area Network), which supports transfers with data rates up to 1 Mbits/s. Due to the higher transmission speed and the standardized functionality, CAN is a very interesting alternative to and improvement on bus systems based on other protocols.

The demands of the automotive market are decreasing the time-to-market required from the initial concept of new control systems to their implementation. The goal of automotive companies is to constantly reduce the development time to reap the full economic and strategic benefits of being quicker to market. The target is to reach a development time of less than 12 months for some applications. At the same time, the complexity of these new systems is growing almost exponentially. While new techniques like model-based control design with executable specifications, rapid control prototyping and hardware-in-the-loop simulation have helped significantly streamline the development process, the new strategies are still being transferred to the production target by hand. During an early project phase, automotive customers also need to explore different silicon architectures provided by semiconductor manufacturers to select the vendors who can offer the best solution at the lowest price.

The increasing legal requirements for safety, emission reduction, fuel economy and onboard diagnostic systems are forcing the market to increase complexity. This complexity must not be a reason for slowing down the introduction of new systems. For efficiency, car manufacturers and system suppliers want to focus on their core competencies and leave the micro-controller complexity to silicon vendors. Competition forces system suppliers to jump to the most “function/cost” effective solution. For this reason it is very dangerous to move in the direction of specific solutions which require a large amount of effort to modify. Therefore the market goes in the direction of standards with clear interfaces. The approach presented overcomes these obstacles by introducing a Configurable I/O System (CIOS) layer. The CIOS encompasses basic software driver objects for engine management systems encapsulating the standard sensors and actuators.