Building integrated test solutions for automotive electronics

At present, automotive electronics accounts for about 25% of the total vehicle cost, and experts predict that it may reach 70% by 2014. Looking back at the relevant predictions in recent years, it seems to be slightly conservative after comparing with the actual situation. In any case, with the increase of people's safety awareness and the desire for energy conservation, the proportion of automotive electronics will continue to grow rapidly. With this rapid development, the test problems faced by test engineers are becoming more and more difficult. In order to meet these test challenges, Tektronix, a leading manufacturer of time domain testing, has created a complete solution for this field.

Hybrid bus testing

As the electronic systems in vehicles become increasingly complex and the number of electronic control units increases rapidly, distributed networks have undoubtedly become an ideal solution. LAN bus and LINK_KEYWORD1 bus are already very familiar. At present, FlexRay and MOST are also entering the market rapidly in order to improve the speed and bandwidth. There are nearly 100 electronic control units (ECUs) that rely on different bus interconnections and need to use gateways to interconnect various buses. Such a complex network carries various signals, including square waves, pulses and even analog signals, which brings huge challenges to test engineers. "This also poses a difficult challenge to test equipment providers, that is, how to achieve test coverage of all networks on a single instrument at the same time." said Todd Baker, senior manager of global regional marketing at Tektronix. According to him, in order to help engineers cope with this challenge, Tektronix has launched mixed-signal test equipment that can cover multiple networks and various signals. With this equipment, it is possible to use rich external event triggering functions to capture signals in different networks at the same time. The typical representative of the test equipment that can realize the above functions is the MSO4000 series. Another outstanding advantage of this equipment is that it contains logic analysis function, which can realize the integration of oscilloscope and logic analysis on one instrument.

Energy saving system test

With the decreasing supply of fossil fuels, automakers are racking their brains to improve energy efficiency, in which precision electronic control systems play an important role. In order to achieve energy conservation, hybrid power is becoming popular, and switching power supplies have been widely used in cars. The switch-mode excitation of the engine and the existence of switching power supplies make many signals in the system transient signals. How to verify the transient load of the system and the transient response of the system has become a key issue in the design of automotive electronic systems. "In order to fully verify the design and truly judge the efficiency of the system, some special items need to be tested, such as the iron loss and magnetic loss of the magnetic components in the system, and the test of the power management chip." Todd Baker said, "Tektronix equipment has a representative and important built-in function, that is, the High Finder function. With this function, the exact location where the system consumes the most power can be accurately determined, thereby providing designers with accurate reference information for problems that exceed the power budget." Of course, in addition to determining the location of the maximum and minimum power consumption, the power distribution diagram can also be used to determine the maximum power, minimum power and average power loss.

Figure 1: A message captured from the CAN bus.

Figure 2: Trigger on specific events and data on the CAN bus and decode all acquired information.

Figure 3: Discovering specific identifiers and data in CAN bus data collection.

Digital RF Test

Digital RF-related systems in automotive electronics include tire pressure monitoring, keyless systems, RFID, and vehicle anti-theft systems. "For such applications, the verification of performance is only one aspect. The important thing is to verify its safety," said Jerry N Mark, product marketing manager at Tektronix. From a safety perspective, there must be complex encryption and decoding, as well as transient RF signals accompanied by many external interferences. For such coding analysis, it is impossible to measure only by traditional time domain analysis and frequency domain analysis. Modulation domain analysis must be added to achieve the capture and analysis of such time-varying transient signals. "In addition to the latest innovative spectrum analysis embedded in Tektronix's latest oscilloscope, it also provides multi-domain on-screen observation capabilities in the frequency domain, time domain, and modulation domain. With this capability, frequency hopping signals and external noise can be captured and analyzed in real time," said Jerry.

Complete digital analysis solution

In the field of automotive electronics, there are numerous microprocessors, microcontrollers, DSPs, and memory units. In this complex digital processing environment with many types, perfect digital analysis is crucial. Digital analysis is also an important part of Tektronix solutions. "In such systems, not only the visualization of various digital signals is required, but also the time-related observation and analysis of digital and analog signals are required." Todd Baker said, "Tektronix's test solutions not only provide engineers with precise timing measurements, but also provide signal integrity measurements, deep debugging and analysis of timing relationships, and other functions." In addition, the use of FPGAs in automotive electronic systems is increasing. Due to their small size and high complexity, the internal signals that can be obtained are limited, and too many debugging circuits cannot be added to the internal circuits. Therefore, verification in this area is becoming a major bottleneck. For this reason, Tektronix provides measurement and analysis capabilities specifically for FPGAs. The feature of this function is that it can be involved in the design stage. In-depth analysis of the FPGA can be achieved without recompiling, solving functional definition errors, system functional interaction errors, and timing and fidelity issues.