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The three major challenges in the power electronics in hybrid and electric vehicles are: System cost, power density and reliability. High temperature power device and packaging technologies increases the power density and reliability while reducing system cost. Advanced Silicon devices with synthesized high-temperature packaging technologies can achieve junction temperature as high as 200C (compared to the present limitation of 150C) eliminating the need for a low-temperature radiator and therefore these devices reduces the system cost. The silicon area needed for a power inverter with high junction temperature capability can be reduced by more than 50 - 75% thereby significantly reducing the packaging space and power device and package cost. Smaller packaging space is highly desired since multiple vehicle platforms can share the same design and therefore reducing the cost further due to economies of scale.

A variety of methodologies to use embedded multicore controllers efficiently has been discussed in the last years. Several assumptions are usually made in the automotive domain, such as static assignment of tasks to the cores. This paper shows an approach for efficient task allocation depending on different system modes. An engine management system (EMS) is used as application example, and the performance improvement compared to static allocation is assessed. The paper is structured as follows: First the control algorithms for the EMS will be classified according to operating modes. The classified algorithms will be allocated to the cores, depending on the operating mode. We identify mode transition points, allowing a reliable switch without neglecting timing requirements. As a next step, it will be shown that a load distribution by mode-dependent task allocation would be better balanced than a static task allocation.

The newly released Distributed System Interface 3 (DSI3) Bus Standard specification defines three modulation levels form which 16 valid symbols are coded. This complex structure is best decoded with symbol pattern recognition. This paper proposes a simplification of the correlation score calculation that sharply reduces the required number of operations. Additionally, the paper describes how the pattern recognition is achieved using correlation scores and a decoding algorithm. The performance of this method is demonstrated by mean of simulations with different load models between the master and the sensors and varying noise injection on the channel. We prove than the pattern recognition can decode symbols without any error for up to 24dBm.

This paper discusses the RDC method utilizing delta-sigma analog-to-digital converter hardware module (DSADC) integrated in the Infineon's microcontroller family. With its higher resolution capability when compared to the regularly used ADC with successive-approximation (SAR), DSADC seems to have more potential. On the other hand, DSADC's inherent properties, such as asynchronous sampling rate and group delay, which when not handled properly, would have negative effects to the rotor positioning system. The solution to overcome those side-effects involves utilization of other internal microcontroller's resources such as timers and capture units, as well as additional software processing run inside CPU. The rotor positioning system is first modeled and simulated in high-level simulation language environment (Matlab and Simulink) in order to predict the transient- and steady state behaviors. The group delay itself is obtained by simulating the model of DSADC module implementation.

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.

In-vehicle communication faces increasing bandwidth demands, which can no longer be met by today's MOST150, FlexRay or CAN networks. In recent years, Fast Ethernet has gained a lot of momentum in the automotive world, because it promises to bridge the bandwidth gap. A first step in this direction is the introduction of Ethernet as an On Board Diagnostic (OBD) interface for production vehicles. The next potential use cases include the use of Ethernet in Driver Assistance Systems and in the infotainment domain. However, for many of these use cases, the Fast Ethernet solution is too slow to move the huge amount of data between the Domain Controllers, ADAS Systems, Safety Computer and Chassis Controller in an adequate way. The result is the urgent need for a network technology beyond the Fast Ethernet solution. The question is: which innovation will provide enough bandwidth for domain controllers, fast flashing routines, video data, MOST-replacement and internal ECU buses?

Recently, vehicle networks have increased complexity due to the demand for autonomous driving or connected devices. This increasing complexity requires high bandwidth. As a result, vehicle manufacturers have begun using Ethernet-based communication for high-speed links. In order to deal with the heterogeneity of such networks where legacy automotive buses have to coexist with high-speed Ethernet links vehicle manufacturers introduced a vehicle gateway system. The system uses Ethernet as a backbone between domain controllers and CAN buses for communication between internal controllers. As a central point in the vehicle, the gateway is constantly exchanging vehicle data in a heterogeneous communication environment between the existing CAN and Ethernet networks. In an in-vehicle network context where the communications are strictly time-constrained, it is necessary to measure the delay for such routing task.

As part of a system model, a PEM fuel cell stack model is presented for functional tests and pre-calibration of control units on hardware-in-the-loop (HiL) test benches. From the basic idea to couple a 1-D membrane model with a spatially distributed abstraction of the gas channel, a real-time capable 1-D+1-D PEM FC stack model is constructed. Fundament for the HiL usage is an explicit formulation of the commonly implicit model equations. With that, not only calculation time can be reduced, but also model accuracy is preserved. A validation using test bench data emphasizes the accuracy of the model. Finally, a runtime and eigenvalue analysis of the stack model proves the real-time capability.

A main challenge when developing next generation architectures for automated driving ECUs is to guarantee reliable functionality. Today’s fail safe systems will not be able to handle electronic failures due to the missing “mechanical” fallback or the intervening driver. This means, fail operational based on redundancy is an essential part for improving the functional safety, especially in safety-related braking and steering systems. The 2-out-of-2 Diagnostic Fail Safe (2oo2DFS) system is a promising approach to realize redundancy with manageable costs. In this contribution, we evaluate the reliability of this concept for a symmetric and an asymmetric Electronic Power Steering (EPS) ECU. For this, we use a Markov chain model as a typical method for analyzing the reliability and Mean Time To Failure (MTTF) in majority redundancy approaches. As a basis, the failure rates of the used components and the microcontroller are considered.

The way to autonomous driving is closely connected to the capability of verifying and validating Advanced Driver Assistance Systems (ADAS), as it is one of the main challenges to achieve secure, reliable and thereby socially accepted self-driving cars. Hardware-in-the-Loop (HiL) based testing methods offer the great advantage of validating components and systems in an early stage of the development cycle, and they are established in automotive industry. When validating ADAS using HiL test benches, engineers face different barriers and conceptual difficulties: How to pipe simulated signals into multiple sensors including radar, ultrasonic, video, or lidar? How to combine classical physical simulations, e.g. vehicle dynamics, with sophisticated three-dimensional, GPU-based environmental simulations? In this article, we present current approaches of how to master these challenges and provide guidance by showing the advantages and drawbacks of each approach.

In addition to basic switching functionality, smart power switches mainly provide diagnostic and protection functions, e.g. for short circuits to the load, which makes it all the more surprising that short circuit protected smart switches have been used for years in automotive applications without there being a precise definition of a short circuit. This article describes what Infineon has done to fill this gap. It was first necessary to define the kind of short circuits likely to occur in automotive applications and to specify the use and operating points of the smart switches. The next logical step was the standardization of the test circuit and application conditions in the AEC (Automotive Electronics Council) to allow an industry-wide comparison of the test 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.

Nowadays automobiles are getting smart and there is a growing need for the physical behavior to become part of its software. This behavior can be described in a compact form by differential equations obtained from modeling and simulation tools. In the offline simulation domain the Functional Mockup Interface (FMI) [3], a popular standard today supported by many tools, allows to integrate a model with solver (Co-Simulation FMU) into another simulation environment. These models cannot be directly integrated into embedded automotive software due to special restrictions with respect to hard real-time constraints and MISRA compliance. Another architectural restriction is organizing software components according to the AUTOSAR standard which is typically not supported by the physical modeling tools. On the other hand AUTOSAR generating tools do not have the required advanced symbolic and numerical features to process differential equations.

More than ever, microcontroller performance in cars has a direct impact on the driving experience, on compliance with improved safety, ever-stricter emissions regulations, and on fuel economy. The simple microcontrollers formerly used in automobiles are now being replaced by powerful number-crunchers with incredible levels of peripheral integration. As a result, performance can no longer be measured in MIPS (Millions of Instructions Per Second). A microcontroller's effectiveness is based on coherent partitioning between analog and digital, hardware and software, tools and methodology. To make an informed choice among the available devices, the designer needs benchmarks that are specific to automotive applications, and which provide a realistic representation of how the device will perform in the automotive environment.

Today the majority of power electronics is developed based on the requirements set by the main fields of application e.g. power generation, power supply, industrial drive and traction. With introduction to automotive applications new requirements have to be taken into account. This paper discusses how interconnection technologies for power semiconductors can be improved to meet the demand for higher temperature capability in HEV applications.

Position detection and control is necessary in modern automotive applications because of remotely controlled actuators, such as window lifters or windshield. In recent years, the demand for reliable actuators for safety critical systems, such as power steering systems, has also increased significantly. This creates a growing demand for fast, accurate and efficient servo motor systems that are increasingly smarter, smaller and cheaper. One interesting option is to use Giant Magneto Resistive (GMR) angle sensors to replace the resolvers, Hall, inductive and Anisotropic Magneto Resistive Effect (AMR) Sensors commonly used today for shaft-angle measurements. In principle, there are functional differences among various angle measurement technologies; thus, the effect of switching between them needs to be analyzed.

More than ever, microcontroller performance in cars has a direct impact on the driving experience, on compliance with improved safety, ever-stricter emissions regulations, and on fuel economy. The simple microcontrollers formerly used in automobiles are now being replaced by powerful number-crunchers whose performance can no longer be measured in MIPS. Instead, their effectiveness is based on a coherent partitioning between analog and digital, hardware and software, tools and methodology. To make an informed choice among the available devices, what the designer needs are benchmarks that are specific to automotive applications, and which provide a realistic representation of how the device will perform in the automotive environment. This presentation will explore the role of new benchmarks in the development of complex automotive applications.

Software developers in the automotive sector must achieve high quality objectives. Many design and implementation errors are avoided by synthesizing code from model-based software specifications using automatic code generators such as ETAS' ASCET. To verify non-functional properties of the implementation, model-based design processes should be complemented with static program analysis tools like AbsInt's StackAnalyzer and timing analyzer aiT. ASCET, StackAnalyzer and aiT can be integrated in a way that the analysis results for code generated by ASCET are conveniently accessible from within the ASCET development environment. This gives ASCET users a direct feedback on the effects of their design decisions on resource usage, allowing to select more efficient designs and implementation methods. In the paper, we present the tools, the experimental integration, preliminary results and plans for further tool integration.

FlexRay1 is a high speed, time triggered and fault tolerant communication protocol, which was specified to meet the requirements of safety-critical automotive applications. The achieved maturity of FlexRay encourages the implementation on silicon. The CIC-3102 device is a standalone controller provided by Infineon Technologies. It runs the wide spread E-Ray3 IP from Bosch. A complete communication node for FlexRay requires additional devices for the physical layer and the application part. The CIC-310 can communicate with a host controller via three different interfaces micro link interface MLI, serial synchronous interface SSC, external bus XMU. Its physical layer interface corresponds to the FlexRay specification. The CIC-310 provides features like intelligent move engines to maximize the achievable data rate as well as to minimize the workload of the host. Therefore, the CIC-310 allows a very flexible and efficient way to build and operate FlexRay nodes.

Increasingly stringent requirements to improve fuel economy and reduce emissions are pushing the automotive industry toward more innovative solutions. To fulfill the demand, OEMs are developing hybrid systems with powerful electronics. The key technology is in all cases the battery. It is the most critical and expensive element of hybrid systems. The battery requires special care, as it must supply up to 400 Volts (V) and have a capacity of up to several kilowatt-hours (kWh). This paper will review the main functions of a Lithium-ion (Li-ion) battery management system, including power on/off, charging/discharging, and computation of the state of charge and state of health. In order to increase the battery lifespan, new functions such as active load balancing must be implemented.