From September 25th to 27th, the 11th Automotive Electronics Innovation Conference (2024 AEIF) and Automotive Electronics Application Exhibition was held in Wuxi Taihu International Expo Center, Jiangsu. At the meeting, Mr. Yang Renping, Head of Marketing Department of Keysight Greater China, shared a keynote speech on "Innovative Testing Technology Helps the Development of Automotive Chip Industry". Mr. Yang Renping looked at the development of automotive electronics from the perspective of Fabless, and analyzed that Keysight can provide customers with targeted solutions from the perspective of testing.
The automobile industry, which carries the dream of human travel, has undergone earth-shaking changes in the past few decades. From the initial mechanical drive to today's electronic assisted driving, every stage has witnessed the progress of science and technology and the wisdom of human beings. Nowadays, the automobile industry is accelerating, and in the 70s and 90s of the last century, it experienced the mechanization of automobiles, and initially assisted driving was mainly electronic.
After entering 2020, the form of the car has undergone earth-shaking changes, it is not only a means of transportation but also an intelligent terminal, including a lot of perception, automatic driving, and communication functions. However, from the perspective of testing, automotive chips face three major challenges.
1. Intelligent automobiles.
The intelligence represented by ADAS and intelligent cockpit SoCs processes more and more data, and the computing power required is getting stronger and stronger, which is a great challenge to interconnection.
The challenges of automotive intelligent testing are mainly focused on intelligent cockpit SoCs and ADAS (advanced driver assistance system) chips. These schools of technology are typically designed with heterogeneous chip architectures, where the CPU is responsible for scheduling, and the main computing tasks are handled by dedicated AI chips and GPUs. In terms of data interaction, CPUs and memory, CPUs and AI chips are connected through high-speed buses, of which PCIe (PCI Express) is a widely used type.
Next, Mr. Yang Renping explained the entire PCIe link testing process from transmitter to receiver.
In the test domain, test points from TP0 to TP5 are defined from transmitter to receiver. For transmitters,. An oscilloscope is typically used for testing, whether it is a real-time oscilloscope or a sampling oscilloscope, to receive the signal waveform output from the transmitter. By looking at the degree of opening, jitter and signal quality of the eye diagram, it is possible to evaluate whether the transmitter meets the requirements of the standard.
In the case of receivers, the signal may experience attenuation and interference when it reaches the receiver due to the influence of the transmission link. As a result, the receiver needs to employ a specialized equalization algorithm to recover the waveform. Receiver testing is more complex, requiring a high-speed bit error meter or arbitrary waveform transmitter to send a pressurized signal to the receiver. This signal can include crosstalk, noise, or attenuation to assess whether the receiver is still able to accurately reproduce the waveform under extreme conditions. This step is crucial for smart automotive testing, as the safety of the car is closely related to the accuracy of these tests.
In addition, the link itself is extremely important. The degree of link matching and loss has a significant impact on the transmitted signal and therefore requires careful testing and optimization.
2. Connected vehicles.
Automotive networking is an important trend in the development of automotive technology, involving many standards, including SBETX for external communication and traditional protocols such as CAN and LINn for internal communication. With the continuous advancement of technology, the connection between the camera and the main control chip has also shown a new trend, that is, the use of high-speed Serdes bus for data transmission. Due to the huge amount of camera data, it is difficult for traditional buses to meet the transmission requirements.
Taking the Serdes bus standard as an example, there are many Serdes bus standards on the market, including private protocols and open standards promoted by MIPI and ASA Alliances. Solutions are provided for both private and public protocols, including the MIPI A-PHY bus. As a member of MIPI A-PHY, Keysight has contributed a lot of test and measurement experience to the recently frozen CTS 1.0 standard and helped the consortium build a reference test system for the standard.
Below is a block diagram of the MIPI A-PHY or ASA test, which works similarly to the PCIe test principle and covers the complete test process from transmit, link to receive.
However, due to the asymmetry of the MIPI A-PHY, ASA bus on the uplink and downlink transmissions, the uplink and downlink tests are slightly different.
It is worth mentioning that Keysight launched conformance testing software based on the MIPI A-PHY CTS 1.0 standard for the first time. The advantage of this software is that it only needs to connect the physical circuit, click on the automated test software, and it will automatically complete dozens of test items and generate a test report that clearly marks which items pass and which ones do not, thus greatly saving the user's time in setting up and viewing test results.
3. Electrification of vehicles.
As the trend towards vehicle electrification progresses, the conversion from IGBTs to silicon carbide with higher frequencies and higher voltages poses a very significant challenge to the requirements of test equipment
The electrification of electric vehicles has undergone a significant shift from traditional IGBT technology to silicon carbide technology.
Silicon carbide, or third-generation semiconductor technology, has the advantage of fast switching speed and the ability to withstand high voltages. At present, there are a large number of cases of silicon carbide process, silicon carbide devices or modules on 400V and 800V platforms. However, the test of silicon carbide also puts forward higher requirements for the performance of the test instrument due to the higher withstand voltage and faster frequency.
Ms. Yannan Ren, Director of Business Operations, Greater China, Keysight Technologies, added that in the field of new energy, Keysight's expertise focuses on three main areas: First, comprehensive testing of battery performance, covering the evaluation of battery cells, battery modules, and battery management systems. Second, Keysight focuses on the testing of electric vehicles and charging piles.
Given that Europe, United States, China, and Japan all have their own charging standards, involving different current, voltage, and charging interface specifications, Keysight has successfully achieved comprehensive coverage of these standards in the past year or two. The testing capacity covers DC, AC charging, as well as European standard, American standard, national standard and other standards, and the power range has been extended to 250 kilowatts.
In addition, a 900 kW test scheme for ultra-fast charging will be launched soon, which supports 1500V voltage and 600 amperes, representing the most advanced technology level in China. It is worth mentioning that this solution has been recognized and verified by more than 100 customers in more than 25 countries around the world, including both vehicle manufacturers and charging pile manufacturers. Finally, there is the testing of dynamic modules.