China's automobile production has surpassed that of the United States to rank first in the world, and will continue to grow in the next 5-10 years. The China Association of Automobile Manufacturers expects that the growth rate of automobile production in 2010 will be around 10%, and it is expected to reach 15 million. At present, many well-known enterprises have emerged in China, including automobile manufacturers, modular system suppliers and component suppliers, electronic equipment suppliers, etc., especially FAW, Second Automobile, BYD, Chery, Geely, Hangsheng, Changan and other local The rapid progress made by manufacturers in independent development and innovation has driven the rapid development of China's automotive electronics industry.
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However, in the face of increasingly complex automotive design needs, especially when it comes to launching mid- to high-end and commercial new energy vehicles, the road to independent innovation and development is not smooth. Tektronix's experts have used the Toyota Lexus 460 with "more than 100 ECUs and software codes that have reached 7 million lines" at an automotive electronics forum held recently, emphasizing the use of electronic components in automobiles, especially high-end cars. The proportion occupied by China is getting higher and higher. “As shown in Figure 1, automotive electronics is concerned with the three major market challenges of automotive design, namely how to meet the requirements of ecology (environmental protection), more comfort and convenience, and enhance safety. The systems and subsystems that solve these challenges are the current automotive electronics. The hot spots and difficulties of design," he pointed out. “The use of LANs, power systems, electronic control units and digital RFID plays an important role in improving vehicle ecology, safety and comfort.
Figure 1: Three major market challenges in automotive design lead to more design hotspots
Four test analysis, one can not be less
Tektronix experts emphasized in their speeches that for powertrains that require improved fuel efficiency or new energy sources, body and audio-visual entertainment systems that help improve driving and entertainment comfort, or safe driving systems such as braking and steering. The use of local area networks (LANs) is increasing to achieve drive control, body control or X-by-wire control; engine control units and power supplies for cars due to the need to increase energy efficiency in cars Systems are becoming more complex, while hybrid and clean fuel diesel technology requires advanced electronic control systems to ensure safety and environmental protection; the use of electronic control units (ECUs) to control basic automotive systems and non-essential automotive systems is becoming the new industry standard. Based on digital technology (MCU, FPGA, etc.), ECU requires a deeper understanding of complex timing and signal integrity issues; automotive safety systems use tire pressure monitoring (TPMS) and RFID systems, which require the development and measurement of real-time RF systems. Efficiently monitor vehicle operation and status.
(1) LAN test analysis
Tektronix experts explained in the presentation that various serial data technologies and applications are being integrated into automotive designs such as CAN, LIN, MOST and FlexRay. Serial communication improves board design because the serial interface is integrated into devices such as processors, ASICs, and FPGAs, resulting in fewer connections and lower total component costs. The final automotive design typically includes multiple serial standards, mixed-signal, mixed data rates, single-ended signals, and differential signals. This requires a versatile and easy-to-use high-quality test and analysis solution to achieve timing and signal between signals. Integrity test analysis and debugging.
For debugging of low-speed serial buses such as CAN and LIN, which are commonly used in automobiles, Tektronix' DPO/MSO4000 series oscilloscopes provide a simple, easy-to-use, complete, high-quality trigger, capture and decode solution. As shown in Figure 2, the oscilloscope series provides search and flagging capabilities to display decoded time-stamped CAN message frames in the event table, a feature not available in other competing products. 
Figure 2: Tektronix DPO/MSO4000 Series Oscilloscope CAN Solutions
For the exciting high-speed differential serial bus FlexRay, the DPO/MSO4000 series also offers a debugging solution. Tektronix' FlexRay physical layer analysis software DPO4AUTOMAX also fully supports physical layer analysis, providing a complete set of tools to evaluate physical layer performance, including eye diagram analysis, simultaneous measurements, timing measurements, time interval error (TIE), and via USB or Ethernet works with an external computer.
(2) Analysis of power system test
The power system is undoubtedly the heart of the car, and the high-quality and stable operation of the electronic circuit related to the power system will largely determine the performance of the vehicle, including the electronic control part realized by the ECU, and the vehicle power circuit. Especially new energy vehicles.
The car ECU calculates the information in real time based on the data returned by sensors placed throughout the car to determine the optimal engine control parameter values. Because the ECU is built into the engine compartment of the car, the noise environment is even worse, and the need for higher frequency analysis is also increasing, especially for microsecond, millisecond, and even nanosecond transients or spikes. The ability to analyze nanosecond-level high-frequency noise with traditional oscilloscopes and probes. Tektronix experts recommend reducing the electrical load on the measurement system, including differential probes with low input capacitance. Tektronix experts also provide signal source-based test methods for some engineers who want to use the signal source for on-site simulation testing of the powertrain electronic control unit. For example, the AFG3000 series function signal generator is used to simulate various automotive sensor signals such as pressure, temperature, speed, Rotating and angular position for functional testing and optimization of engine control units in automotive applications. 
Figure 3: Measuring and optimizing the engine control unit with the AFG302xB and AFG3011
For the characteristics of complete floating test in automotive electronics testing, Tektronix experts recommend that engineers use relatively high-priced but higher-performance differential probes in the test to ensure that the effects of the common-mode portion are eliminated. “Sometimes we have a smooth board test, but there are problems when running in the system. In many cases, it may be that the test failed to take into account the impact of the common mode part,†he pointed out. He further shared with Tektronix Tektronix' leading technology on probes: "For example, TDP probes are particularly suitable for floating voltage measurements with input capacitances less than 1pF and industry-unique probe programmable control features for automated test systems. The realization."
(3) Analysis of digital devices
In the electronic control unit, infotainment system and security subsystem in the car, more and more digital ICs such as MCU and FPGA are used to form various embedded systems. Tektronix's expert analysis pointed out that unlike the CPU that needs to use logic analyzer for multiple channels, complex triggering, conditional storage, disassembly, and source code level software debugging, for MCU and FPGA debugging, one has excellent performance and complete functional configuration. A mixed signal oscilloscope (MSO) is sufficient.
The following are two common timing measurements in embedded systems: event times are far apart - requiring multiple channels (long record length) to be acquired with high timing resolution (high sample rate) over long periods of time; digital state transitions— - It is required to capture the signal in a short time, but the timing resolution is very high. Real-time MSOs, such as the MSO4000 with the MagniVu application module, are particularly well-suited for monitoring changes over time. In addition, the MSO4000's 16 digital channels can be individually leveled, allowing different logic types to be used in a single design and triggering setup time/hold time violations across multiple channels.
For FPGA debugging challenges, Tektronix experts listed the following: 1. Design specifications and complexity are increasing, access internal signals are limited; 2. Time-to-market pressure forces product development and debugging cycles to be shortened; 3. In FPGAs Adding debug circuitry can affect design performance and take up valuable chip space and more. 
Figure 4: Cost-Effective FPGA Real-Time Logic Debug Solution Tektronix offers a cost-effective FPGA real-time logic debug solution to address these challenges: MSO4000 Mixed Signal Oscilloscope or TLA Series Logic Analyzer (>v4.3) + FS2 FPGAView Control The software, the multiplexer and JTAG cable of the FPGA manufacturer, can be easily completed in 4 steps: create an interface module? Configure the FPGAView for the debug environment to map the FPGA pins to the MSO4000 or TLA series logic analyzer for measurement.
In addition, Tektronix also provides DPOxAudio audio analysis module, which can decode and analyze the audio bus I2S of the car entertainment system.
(4) Digital RF test
Some new safety and monitoring system technologies have widely used RFID in automotive electronic systems such as tire pressure monitoring (TPMS), immobilizers, keyless entry systems, parking sensor assemblies and systems. The application of RFID is increasing. Some of the technologies applied in the past high-class cars will become the standard for most cars in the future. For example, the call for mandatory standards for tire pressure monitoring systems is increasing day by day. Monitoring Tektronix experts also pointed out that in reversing radar applications. In the past, domestic automakers used direct purchase modules for applications, but now many of them start designing themselves, which will inevitably promote wider application in more cars.
As mentioned above, in recent years, automotive electronic systems have become more and more complicated, and more switching power supplies with stronger EMI characteristics have entered the automotive electronic systems. These challenges for RF testing, using traditional spectrum analysis tools. These transient signals are tested. Tektronix experts have given some suggestions for automotive RF testing for engineers' reference: Tektronix' dual-channel signal generator AFG3022B can be used to generate 4-bit RFID pattern signals and synchronous trigger signals for 134.2kHz RFID receiver ICs. Perform functional tests; use arbitrary waveforms and function generators to generate complex signal environments in automobiles. For example, for reverse radar pulsed noise figure measurement, an easy-to-use dual-channel AFG3252 can be used to generate two sync pulse signals as RF amplifiers. Power supply, triggering noise figure measurement on the spectrum analyzer.
Summary of this article
In recent years, China's automotive electronics design field has become increasingly active. Compared with previous manufacturers' major direct use of foreign mature module products, many manufacturers have increased their independent research and development efforts. Local automotive electronics design companies are also actively seeking to cooperate with vehicle manufacturers. Cooperation.
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