Search Results

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.

Braking systems require a high system safety level: New safety concepts need to be implemented by reducing the system complexity. Microcontrollers with special safety functions are available with implemented features, self detecting and compensating different types of faults. Today usually two microcontrollers are used to check each other. Power devices provide microcontroller supplies and drive motors and valves; internally the functions are supervised to avoid incorrect system behaviour due to wrong voltages, currents, missing loads or other malfunctions. Bus interfaces, signal conditioning and interfaces for high voltage signals are integrated into the power system ICs. Latest BIPOLAR-CMOS-DMOS power technologies enable the power semiconductors to integrate logic functions.

Modern semiconductor devices enable highly efficient conversion of electrical power. Together with the microcontroller, they are the key elements for generation of the alternating currents from the car's DC supply that are necessary to drive high-performance units such as starter-alternators. These allow the combustion engine to crank up in several 100 ms and deliver up to 15 kW of electrical power. Smart driver ICs such as the TLE6280 enable the fast development of the interface between the microcontroller and the power switches. Currents of some 100A can be handled with the new OptiMOS FETs. Their rugged and ultra-low ohmic technology and their innovative packaging concepts, such as Power Modules and Power-Bonded MOSFETs, allow the building of compact and efficient control units.

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.

This article describes the effects of a future 42V automotive electrical system on the vehicle electronics, focusing mainly on the consequences for power semiconductors and their associated technologies. Taking the example of a door module, it then shows how existing 14V loads can be operated on the 42V PowerNet and what advantages result for operation of adjusted 42V loads. The following different problem-solving approaches are presented for typical loads such as power windows, electrically positioned and heated outside mirrors, and central locking: Power windows: A test motor specially developed for the 42V supply is continuously operated directly from the electrical system using suitable power semiconductors. Central locking: A conventional 14V motor is operated at 42V, its operating point being set using pulse width modulation (PWM). Remaining door module: Smaller 14V mirror motors and the control electronics are supplied from a second 14V system.