Electromagnetic compatibility test system for integrated circuit, part or whole vehicle

Abstract

The invention provides an electromagnetic compatibility test system for an integrated circuit, a part or a whole vehicle. The system comprises an interference signal injection or receiving device, a test board, an oscilloscope, an upper computer, a power supply and an isolation communication device, the interference signal injection or receiving device is used for sending a quantitative interference signal to the test board or receiving and measuring the size of the interference signal of the test board; the test board is used for bearing a tested integrated circuit and carrying out an electromagnetic compatibility test according to a working state specified by the upper computer; the isolation communication device is used for performing photoelectric conversion on a control signal and a monitoring signal corresponding to the electromagnetic compatibility test to form photoelectric isolation; the oscilloscope is used for measuring the waveform of the monitoring signal; and the upper computer is used for controlling the test process and analyzing the monitoring signal to judge the test result. The isolation communication device is used for cutting off electrical connection between the test board and the upper computer and the oscilloscope, it is ensured that the test board is not affected by the outside in the electromagnetic compatibility test process, and the accuracy of the electromagnetic compatibility test is improved.

Description

Technical Field

[0001] This application relates to the field of optoelectronic communication technologies, and particularly to an electromagnetic compatibility test system for integrated circuits, components or entire vehicles. Background Art

[0002] With the rapid development of automobiles, there are more and more automotive electronic components and their functions are becoming more and more complex; traditional windshield wipers, headlights, HUDs, compressors, etc. all require function control. To simplify the connections between them, LIN / CAN / CAN FD communications are usually used; in the field of electromagnetic compatibility (EMC) of automotive electronic products, LIN / CAN / CAN FD communication buses are also needed to control each module to achieve the functions of the entire vehicle; during the test process, single-line electrical connections need to be achieved, and these electrical connections often bring electromagnetic interference noises, which will introduce uncertain factors to the EMC test, resulting in great disputes in the test and affecting the determination of the final result. In the field of integrated circuit EMC testing, single chips with LIN / CAN / CAN FD communication functions also need to be tested by simulating the operating state of the chips. Therefore, the same problems as those in component EMC testing will also be faced during integrated circuit testing. Summary of the Invention

[0003] This application provides an electromagnetic compatibility test system for integrated circuits, components or entire vehicles, which is used to solve the problem that the electrical connection of the communication bus in related technologies will cause electromagnetic interference to the EMC test.

[0004] In the first aspect of this application, an electromagnetic compatibility test system for integrated circuits, components or entire vehicles is provided. The electromagnetic compatibility test system for integrated circuits, components or entire vehicles includes: An interference signal injection or reception device, a test board, an oscilloscope, a host computer, a power supply, and an isolation communication device; the interference signal injection or reception device is respectively connected to the test board and the host computer, and the isolation communication device is electrically connected to the test board, the oscilloscope, the host computer, and the power supply respectively; The interference signal injection or reception device is used to send a quantitative interference signal to the test board or receive and measure the magnitude of the interference signal of the test board. When injecting, a signal generator and a power amplifier are used to generate radio frequency interference energy; when receiving, a spectrum measurement receiver is used to receive the radio frequency energy of the test board; The test board is used to carry the integrated circuit to be tested and perform electromagnetic compatibility tests according to the working state specified by the host computer; The isolation communication device is used to perform optoelectronic conversion on the control signal and monitoring signal corresponding to the electromagnetic compatibility test to form optoelectronic isolation; The oscilloscope is used to measure the waveform of the monitoring signal; The host computer is used to control the test process and analyze the monitoring signal to judge the test result.

[0005] Optionally, in the first implementation manner of the first aspect of the present application, the isolation communication device includes a mode controller, a pattern analyzer, a pattern generator, an isolator, and a power isolation management module; The mode controller is used to configure the LIN / CAN / CAN FD communication mode according to the test requirements; The pattern analyzer is used to monitor and analyze the LIN / CAN / CAN FD bus data in real time to detect whether there is an abnormality during the communication process; The pattern generator is used to send standardized LIN / CAN / CAN FD data frames and definable test signals; The isolator is used to convert electrical signals into optical signals and transmit them over a long distance through optical fibers by adopting laser communication technology to achieve optoelectronic isolation; The power isolation management module is used to provide a stable power supply for the isolation communication device.

[0006] Optionally, in the second implementation manner of the first aspect of the present application, the mode controller includes a monitoring mode control and an excitation mode control unit; The monitoring mode control unit is used to detect the test status and read the test result, and feedback the test result to the host computer; The excitation mode control unit is used to switch different working modes according to the control instructions issued by the host computer and control the signal transmission.

[0007] Optionally, in the third implementation manner of the first aspect of the present application, the pattern analyzer and the pattern generator include protocol filters supporting LIN / CAN / CAN FD and a coupling and decoupling network for control signals and monitoring signals; the pattern analyzer and the pattern generator are configured by the software of the host computer to distinguish different working modes.

[0008] Optionally, in the fourth implementation manner of the first aspect of the present application, the power isolation management module includes a power supply with a decoupling network.

[0009] Optionally, in the fifth implementation manner of the first aspect of the present application, the protocol filter is used to send and / or respond to the control signals and monitoring signals according to a preset program; the control signals and monitoring signals include communication test signals carried by LIN frames, CAN frames, CAN FD frames, as well as non-standard control signals and monitoring signals.

[0010] Optionally, in the sixth implementation manner of the first aspect of the present application, the isolation communication device includes a first isolation communication device and a second isolation communication device. The first isolation communication device communicates with the second isolation communication device through an optical fiber. The first isolation communication device is electrically connected to the test board, and the second isolation communication device is electrically connected to the oscilloscope and the upper computer respectively; The first isolation communication device is configured to convert the electrical signal sent by the test board into an optical signal and transmit it over a long distance through the optical fiber; The second isolation communication device is configured to convert the optical signal transmitted by the first isolation communication device back into the electrical signal and send the electrical signal to the oscilloscope and the upper computer respectively.

[0011] Optionally, in the eighth implementation manner of the first aspect of the present application, the test board includes a first node and a second node. The first node and the second node are respectively connected to the first isolation communication device through a power interface, a control signal interface, and a monitoring signal interface; The power interface includes a power supply and GND. The power supply is used for the first isolation communication device to supply power to the test board; the GND interface is the common ground of the test board and the first isolation communication device, which is used to maintain a consistent signal potential reference; The control signal interface includes, but is not limited to, the TXD interface, the EN / WAKE interface, and other signal interfaces that can be customized by the upper computer software, and is used for the first isolation communication device to send control and data signals to the test board; The monitoring signal interface includes, but is not limited to, the RXD interface, the INH interface, and other signal interfaces that can be customized by the upper computer software, and is used for the test board to send working status and data signals to the first isolation communication device.

[0012] In summary, the beneficial effects of the present invention are as follows: By using an isolation communication device (such as optoelectronic conversion) to cut off the electrical connection between the test board and the upper computer and the oscilloscope, interference such as ground loops and common-mode noise is eliminated, ensuring that the test board is not affected by the outside during the electromagnetic compatibility test and improving the accuracy of the electromagnetic compatibility test. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic structural diagram of an electromagnetic compatibility test system for integrated circuits, components, or vehicles provided in Embodiment 1 of the present application; Figure 2 It is a schematic structural diagram of an electromagnetic compatibility test system with a dual isolation communication device provided in Embodiment 2 of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0014] In order to make the invention object, features, and advantages of the present application more obvious and understandable, the following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0015] In order to solve the problem that the electrical connection of the communication bus in the related art will cause electromagnetic interference to the EMC test, Embodiment 1 of the present application provides an electromagnetic compatibility test system for integrated circuits, components, or a whole vehicle, such as Figure 1 FIG. 6 is a schematic structural diagram of the electromagnetic compatibility test system for integrated circuits, components, or a whole vehicle provided in Embodiment 1. The electromagnetic compatibility test system for integrated circuits, components, or a whole vehicle includes: an interference signal injection or reception device, a test board, an oscilloscope, a host computer, a power supply, and an isolation communication device; the interference signal injection or reception device is respectively connected to the test board and the host computer, and the isolation communication device is electrically connected to the test board, the oscilloscope, the host computer, and the power supply; The interference signal injection or reception device is used to send a quantitative interference signal to the test board or receive and measure the magnitude of the interference signal of the test board. When injecting, a signal generator and a power amplifier are used to generate radio frequency interference energy; when receiving, a spectrum measurement receiver is used to receive the radio frequency energy of the test board; The test board is used to carry the integrated circuit under test and perform electromagnetic compatibility tests according to the working state specified by the host computer; The isolation communication device is used to perform optoelectronic conversion on the control signal and monitoring signal corresponding to the electromagnetic compatibility test to form optoelectronic isolation; The oscilloscope is used to measure the waveform of the monitoring signal; The host computer is used to control the test process and analyze the monitoring signal to judge the test result.

[0016] Specifically, the interference signal injection or reception device is connected to the test board. In the injection mode, the interference signal injection or reception device uses a signal generator and a power amplifier to generate radio frequency interference energy, which is injected onto the test board according to a preset quantity parameter for interference testing of the integrated circuit under test carried on the test board. In the reception mode, the interference signal injection or reception device uses a spectrum measurement receiver to receive and measure the radio frequency energy emitted by the test board, so as to determine the actual level of electromagnetic interference. The test board undertakes the task of carrying the integrated circuit under test and conducts corresponding electromagnetic compatibility tests according to the working state specified by the host computer. Its internal structure can respond to a predetermined control signal to meet the test requirements in different states, so as to comprehensively evaluate the performance of the integrated circuit under test under the action of interference signals. At the same time, the isolation communication device forms optoelectronic isolation by performing optoelectronic conversion on the control signals and monitoring signals among the test board, the oscilloscope and the host computer. This device can not only convert the electrical signals generated by the test board into optical signals for transmission, but also convert the optical signals transmitted from the remote end back into electrical signals, thus ensuring the anti-interference ability of signal transmission and the integrity of data during the test. The use of the isolation communication device effectively avoids signal distortion and noise interference caused by electromagnetic interference, making the entire system more stable and reliable. The oscilloscope, as a waveform measurement device in the test system, is used to capture and display the waveforms of monitoring signals in real time. By observing the waveforms of the collected signals, the changes of various signal parameters during the test can be intuitively reflected, which is convenient for operators to make a preliminary judgment on the test results based on the waveform characteristics. In addition, through the close cooperation with the isolation communication device and other modules, the host computer realizes the centralized control and monitoring of the entire test process. The host computer can issue control instructions according to the preset test plan, and by collecting the monitoring signals fed back by the oscilloscope, the isolation communication device and the interference signal injection or reception device, it can analyze the parameters in real time during the test and record the data, thus providing a basis for the determination of subsequent test results. The modules of this system are organically connected to form a closed-loop feedback control mechanism. Among them, the interference signal injection or reception device, the test board, the isolation communication device, the oscilloscope and the host computer constitute a well-structured and cooperative test platform. This test platform can not only accurately inject a quantitative interference signal, but also accurately receive and quantify the changes in radio frequency energy on the test board. At the same time, through the optoelectronic conversion of the isolation communication device, effective electrical isolation between modules is achieved, thus preventing external interference from interfering with control signals and monitoring signals. On the basis of maintaining the basic process of traditional electromagnetic compatibility testing, the design scheme of this system introduces optoelectronic isolation technology and the concept of multi-module cooperative testing, making the overall test process more compact, data transmission more stable, and capable of comprehensively and accurately evaluating the anti-interference performance of integrated circuits in a complex electromagnetic environment, so as to achieve the purpose of efficiently testing the electromagnetic compatibility of integrated circuits.

[0017] Optionally, in the immunity test scenario, the interference signal injection device injects pulse interference with adjustable amplitude into the LIN / CAN / CAN FD bus of the test board, such as EFT / Burst pulses with a 5 ns rising edge and an amplitude of ±4 kV. The change in the communication state of the test board under the action of interference is output to the isolation communication device through its monitoring interface. The optoelectronic conversion module uses a laser transceiver for optoelectronic conversion. After modulating the electrical signal into an optical signal at the laser emission end, it is transmitted through an optical fiber, and then the optical signal is demodulated back into an electrical signal at the optical reception end, thus realizing signal isolation and long-distance transmission. This conversion process can be completed at a rate of 1 Gbps, ensuring a timing accuracy of the order of 10 ns and effectively retaining the integrity and transient details of high-speed LIN / CAN / CAN FD signals. The converted electrical signal is transmitted in two paths: one path is sent to a waveform recorder with a trigger storage depth of 1 M points on the oscilloscope to capture signal distortions caused by transient interference (such as signal overshoot and undershoot caused by pulse superposition); the other path is transmitted to the protocol analysis software of the upper computer to calculate the bit error rate and frame loss rate in real time. This dual-path parallel processing mechanism enables the system to not only capture transient waveform details (such as signal overshoot caused by pulse superposition) but also statistically analyze communication quality indicators (such as the correlation curve between interference intensity and bit error rate).

[0018] The hardware design of the test board is optimized for electromagnetic compatibility test requirements: its communication bus is configured with an impedance matching network (such as a 120 Ω termination resistor), a π-type filter circuit (a combination of a 10 μH inductor and a 100 nF ceramic capacitor) is deployed at the power supply port, and SMA interfaces are set at key signal test points for easy connection of near-field probes. When the interference signal injection device applies radio frequency continuous wave interference, the radiation emission characteristics of the test board are coupled to the monitoring port through the near-field probe, and the isolation communication device samples the signal through an 18-bit high-precision ADC and then transmits it to the oscilloscope for spectrum analysis through optoelectronic conversion. At this time, the control software of the upper computer synchronously adjusts the frequency of the interference signal injection device (such as scanning from 150 kHz to 1 GHz) and automatically marks the frequency points exceeding the CISPR 25 limit, generating a test report containing the peak frequency, Q value, and exceeded amplitude.

[0019] The host computer software realizes full-process automatic control through a hierarchical architecture: the underlying driver layer directly controls the FPGA chip of the interference signal injection device to generate complex modulation signals (such as the radio frequency carrier of AM modulation), the middle protocol layer analyzes the CAN / LIN data frames uploaded by the isolation communication device, and the top application layer integrates machine learning algorithms, which can optimize the interference signal injection mode according to historical test data. For example, in iterative testing, the software will dynamically adjust the repetition frequency of pulse interference and quickly locate the failure threshold of the integrated circuit under test through the dichotomy method, with an efficiency improvement of more than 5 times compared to traditional manual testing. After the test is completed, the system automatically generates a three-dimensional electromagnetic compatibility matrix diagram to intuitively display the sensitivity distribution of the circuit under test at different frequencies, amplitudes, and modulation methods.

[0020] In an optional implementation manner of this embodiment, the isolation communication device includes a mode controller, a pattern analyzer, a pattern generator, an isolator, and a power isolation management module; The mode controller is used to configure the LIN / CAN / CAN FD communication mode according to the test requirements; The pattern analyzer is used to monitor and analyze the LIN / CAN / CAN FD bus data in real time to detect whether there are any abnormalities during the communication process; The pattern generator is used to send standardized LIN / CAN / CAN FD data frames and definable test signals; The isolator is used to convert electrical signals into optical signals and transmit them over long distances through optical fibers by adopting laser communication technology to achieve optoelectronic isolation; The power isolation management module is used to provide stable power for the isolation communication device.

[0021] Specifically, the isolation communication device integrates five core modules: a mode controller, a pattern analyzer, a pattern generator, an isolator, and a power isolation management module. The mode controller is implemented using an FPGA chip and communicates with the host computer through an SPI interface. It can dynamically configure the LIN / CAN / CAN FD communication rate (such as 19.2 kbps for LIN or 500 kbps for CAN), frame format (standard frame / extended frame), and working mode (active transmission / silent listening). For example, it can be switched to the bus listening mode during anti-interference tests to capture the abnormal responses of the test board under electromagnetic interference. The pattern generator is integrated inside the FPGA and has built-in LIN 2.0 / 2.1 and CAN 2.0B protocol stacks. It can programmatically generate test frames containing random padding bytes, checksums, and error injections. Its transmission period can be precisely adjusted to the microsecond level, meeting the requirements of the ISO 11898-2 standard for bus timing accuracy. The pattern analyzer consists of a hardware protocol parsing chip and an error rate statistics module. Its input end is connected to the bus differential signal line through a high-speed comparator to continuously monitor the bus level status and extract the data field content. When a bit error (such as the dominant bit duration exceeding 10% of the nominal value), format error (such as CRC check mismatch), or response error is detected, an interrupt signal is immediately triggered and uploaded to the host computer through the isolator. For example, during the conducted susceptibility test, when the test board is interfered by a 1 V / m RF field strength and causes a bit stuffing error in the CAN frame, the analyzer can accurately identify the error location and record the correspondence between the interference frequency and the error code type.The structure of the isolator includes a laser emission module, an optical fiber transmission unit, and a photoelectric receiving module. Its working process is as follows: First, the electrical signal from the test board or other circuit modules is preprocessed and amplified and then sent to the laser emission module. The laser emission module uses a pre-modulated laser (such as a VCSEL or DFB laser) to convert the electrical signal into a corresponding optical signal. During this process, the frequency, phase, and amplitude information of the original signal are maintained through modulation, thus ensuring the accuracy and integrity of the signal conversion; Subsequently, this optical signal is transmitted through a dedicated optical fiber transmission unit. Optical fiber transmission has the characteristics of low attenuation, wide bandwidth, and high electromagnetic interference resistance, enabling the signal to maintain stability and high fidelity even during long-distance transmission. At the same time, it effectively isolates external electromagnetic interference and ground potential interference, achieving good electrical isolation; When the optical signal reaches the receiving end of the isolator, a high-sensitivity photodetector (such as a PIN photodiode or APD) in the photoelectric receiving module converts the optical signal back into an electrical signal. During this conversion process, amplification and filtering processes are combined to restore the original characteristics of the signal and ensure that the converted electrical signal has low distortion and a high signal-to-noise ratio, thus meeting the requirements of the subsequent system for signal accuracy; In addition, due to the use of laser communication technology, the isolator has the ability to transmit high-speed data. Its low latency and high bandwidth characteristics enable the system to maintain excellent performance when performing high-frequency and high-speed signal exchanges. This design not only effectively eliminates the ground loop problem that may occur in traditional electrical connections, but also realizes long-distance signal transmission through the use of optical fibers, enabling the control and monitoring modules of the system to be far away from the test environment with severe electromagnetic interference. The power isolation management module includes an isolated DC-DC converter and a low-dropout linear regulator (LDO). Its input terminal is connected to an external 12V power supply, and its output terminal provides regulated power supplies of 5V, 3.3V, and 1.2V for each module. Among them, the DC-DC module adopts a transformer-coupled design, and a creepage distance of 3mm is set between the primary and secondary windings to ensure that the internal logic circuit of the device can still work stably when the test board is subjected to a 4kV surge impact. The power supply rejection ratio (PSRR) of the LDO chip reaches 60dB at 100kHz, effectively filtering out high-frequency noise on the power line of the test board. During the test process, the host computer first sets the communication parameters through the mode controller and starts the pattern generator to send test frames. The pattern analyzer synchronously monitors the bus status. When an abnormal response of the test board is detected, the isolator converts the error data packet together with the timestamp information into an optical signal and uploads it. The host computer generates a three-dimensional correlation map containing the error type, occurrence time, and interference intensity based on this. This design significantly improves the diagnostic accuracy of electromagnetic compatibility faults through the collaborative analysis of the protocol layer and the physical layer. At the same time, the optical fiber isolation technology enables the test system to maintain the reliability of the monitoring data link even when applying high-intensity interference.

[0022] In an alternative implementation of this embodiment, the isolator includes a coupling port and a coupling network; the coupling port is used to connect to an external LIN / CAN / CAN FD bus to achieve signal input or output and isolate electrical signals; the coupling network is used to condition the signals on the LIN / CAN / CAN FD bus.

[0023] Specifically, the functions of electrical isolation and signal conditioning are achieved through the synergistic effect of the coupling port and the coupling network. The coupling port of the isolator is physically docked with the external LIN / CAN / CAN FD bus using a shielded connector, and internally integrates a bidirectional transient voltage suppression device and a common-mode noise filter. Among them, the transient suppression device is connected across the bus differential line in a symmetric layout manner to absorb the high-voltage spikes generated by surges or electrostatic discharges and limit the abnormal voltage within a safe range; the common-mode filter suppresses the common-mode current between the bus and the device through a magnetic winding structure and blocks the conduction path of high-frequency interference. The coupling network is composed of multiple filtering units, and the filtering units use a resistor-capacitor combination circuit to filter out noise interference in specific frequency bands. For example, when the bus signal is transmitted to the coupling network, its high-frequency noise components are first attenuated by the RC filtering network. This design combines physical isolation and active filtering, which not only retains the integrity of the bus signal but also eliminates the impact of external interference on the test system, enabling the accurate capture of the timing characteristics and data content of bus communication even in a strong electromagnetic interference environment, and significantly improving the reliability and accuracy of electromagnetic compatibility testing of in-vehicle electronic systems.

[0024] In an alternative implementation of this embodiment, the mode controller includes a monitoring mode control and an excitation mode control unit; the monitoring mode control unit is used to detect the test status and read the test results, and feedback the test results to the host computer; the excitation mode control unit is used to switch different working modes according to the control instructions issued by the host computer and control signal transmission.

[0025] Specifically, the monitoring mode control unit is used to detect the current test status and read the test results. During the test process, this unit collects signal data from each test module, processes these data in real time, generates result information related to the test status, and then transmits these test results to the host computer through an internal communication channel, thereby realizing continuous monitoring of the test process and data feedback. This process ensures the real-time update of the test status and the accuracy of the feedback information. At the same time, the excitation mode control unit switches the working mode of the test system according to the control instructions issued by the host computer and controls the transmission of relevant signals simultaneously. This unit can automatically switch between different modes according to the instructions of the host computer, such as starting a specific interference signal injection or interference signal reception process at a certain test stage, thereby providing flexibility and adjustability for the test process. Through the control of the excitation mode control unit, the test system can automatically execute different test tasks at a predetermined timing and adjust the test process when necessary to ensure the coordinated work of each module to complete the overall test goal. The monitoring mode control unit and the excitation mode control unit form a complete closed-loop feedback system through a close logical relationship and data interaction. Among them, the monitoring mode control unit records and feedbacks the test status in real time, while the excitation mode control unit actively adjusts the test process according to the information feedback. This structure not only enables the system to efficiently respond to the instructions of the host computer during electromagnetic compatibility testing, but also ensures the accuracy of data collection and the automation of process control during the test process, thereby enhancing the intelligence level and flexibility of the system while maintaining test stability. Thus, this mode controller can ensure the reliability and efficiency of the test system in the face of a changing test environment, and at the same time provide users with timely test data feedback and work status reports, making the entire electromagnetic compatibility test process more accurate and convenient, meeting the requirements of real-time, stability and efficiency for integrated circuit electromagnetic compatibility testing, and thus achieving beneficial effects.

[0026] In an optional implementation manner of this embodiment, the pattern analyzer and the pattern generator include protocol filters that support LIN / CAN / CAN FD, protocol filters, and coupling and decoupling networks for control signals and monitoring signals; the pattern analyzer and the pattern generator are distinguished from different working modes through software configuration of the host computer.

[0027] Specifically, the protocol filter is used to preprocess and filter data signals under different communication protocols. This filter can classify and screen input signals according to preset protocol parameters, enabling the subsequent signal processing module to capture and analyze data frames targeted. At the same time, this protocol filter is also compatible with multiple communication standards, ensuring that the system can still maintain a consistent processing effect when facing different data formats. The coupling and decoupling network is responsible for appropriately coupling control signals and monitoring signals, which can not only achieve synchronous transmission between signals but also separate each signal when necessary, thus avoiding signal interference or distortion. This network structure can reduce noise introduction during high-frequency data transmission and maintain signal quality. The pattern analyzer is mainly used to monitor and analyze data signals from the system under test in real time. After the signals it collects are processed by the protocol filter and the coupling network, it can provide detailed signal timing, error frame, and data integrity information, and transmit this information to the host computer for further processing. The pattern generator relies on the same hardware structure, but its working mode is defined as the active interference signal injection mode after being configured by the host computer software. This module generates standardized data frames or non-standard test signals according to a preset program. These signals can be used to simulate communication situations under various working scenarios, thereby verifying the anti-interference ability and stability of the system. Through the software configuration of the host computer, the pattern analyzer and the pattern generator can flexibly switch between different working modes. The host computer selects the corresponding mode according to the test requirements and issues parameters and instructions through software, enabling the pattern analyzer to focus on monitoring and recording data, while the pattern generator stimulates the target system with signals according to a predetermined test plan. This mode switching and flexible configuration effectively meet the different requirements for data acquisition and interference signal injection in different test scenarios, thus forming a closed-loop test system.

[0028] It should be noted that the design of this embodiment not only realizes the efficient processing and real-time monitoring of multi-protocol data but also ensures the accurate separation and synchronous transmission between signals in the system through the reasonable application of the coupling and decoupling network, making the entire test process have higher accuracy and stability. Therefore, in the electromagnetic compatibility test of integrated circuits, it can accurately reflect the actual working state of the system under test and detect potential interference problems, thereby providing strong data support for subsequent test data analysis and system improvement.

[0029] In an alternative embodiment of this embodiment, the power isolation management module includes a power supply with a decoupling network.

[0030] Specifically, the main purpose of the power supply with a decoupling network is to solve the system stability problem caused by power fluctuations of in-vehicle electronic devices in a complex electromagnetic environment. The decoupling network can effectively filter out high-frequency noise interference (such as transient pulses generated by the ignition system or ripples introduced during motor operation) by setting up a combination of components such as capacitors and inductors at the power output end (for example, using a parallel structure of a 0.1 μF ceramic capacitor and a ferrite bead), and at the same time suppress the mutual interference generated between different circuit modules through the power supply path.

[0031] In an optional implementation manner of this embodiment, the protocol filter is used to send and / or respond to control signals and monitoring signals according to a preset program; the control signals and monitoring signals include communication test signals carried by LIN frames, CAN frames, and CAN FD frames, as well as non-standard control signals and monitoring signals.

[0032] Specifically, in this embodiment, the protocol filter is used to send and / or respond to control signals and monitoring signals according to a preset program, including communication test signals carried by LIN frames, CAN frames, and CAN FD frames, as well as non-standard control signals and monitoring signals. The core components of the system include a protocol filtering module, a communication transceiver, and a signal processing unit. The main function of the protocol filter is to achieve intelligent management of the vehicle network or industrial bus system by identifying, filtering, and processing communication signals in different formats. The protocol filtering module is used to analyze and identify input signals. It can classify and process signals according to set protocol standards, such as ISO 11898-1 (applicable to CAN and CAN FD) and LIN 2.x protocol. In the specific implementation process of CAN transceiver signals, the protocol filter can receive test signals at different rates, such as the 250 kHz periodic signal of the standard CAN frame, and the 2 Mbit / s and 5 Mbit / s data frames in the CAN FD frame. The filter adopts a combination of hardware and software to analyze the format, data rate, and bit width of the signal in real time, and decides whether to forward or block signal transmission according to preset conditions. This method can effectively reduce unnecessary bus load and improve the real-time performance and reliability of the system. The communication transceiver, as the execution unit of the protocol filter, undertakes the physical layer transmission task of signals. In the normal operation mode, the CAN transceiver receives and processes the test signals screened by the protocol filter, such as TX1 (for standard CAN communication test) and TX2 (for CAN FD test). The protocol filter ensures that only signals meeting the preset conditions are allowed to pass, thus avoiding the influence of interference signals or incorrect data. In the low-power mode, the protocol filter can also monitor specific wake-up signals, such as TX3 (single wake-up signal of the standard CAN transceiver) and TX4a - TX4i (CAN transceiver test signals for some network functions). Once a qualified wake-up signal is detected, the protocol filter can trigger the communication transceiver to enter the normal working mode, realizing intelligent power consumption management. In addition, the signal processing unit combines filtering algorithms and anti-interference technologies to further improve signal quality. For example, to reduce the influence of jitter, the protocol filter adjusts the oscillator frequency of the CAN FD controller to make it consistent with the CAN clock frequency, and conducts Rx wave mask tests using a signal generator with appropriate timing to minimize signal jitter. For the test and management of LIN transceiver signals, the protocol filter is used to analyze and manage LIN signals, including the identification, screening, and processing of LIN frames. The frequency of the LIN frame is generally set to 10 kHz, the period is 9 ms, the frame length is 4 ms, and the signal amplitude is V. In this embodiment, the protocol filter can detect and analyze the data stream on the LIN bus in real time, and screen out valid signals through preset rules, thereby improving the accuracy of communication.It can identify the host and slave communication modes of the LIN protocol and automatically adjust the timing to ensure that the synchronization field sent by the host matches the data frame responded by the slave. In addition, the protocol filter can filter out interference signals or abnormal data packets, reduce the bus burden, and improve communication efficiency.

[0033] It should also be noted that the protocol filter is applicable not only to standard communication signals such as LIN frames, CAN frames, and CAN FD frames, but also to non-standard control signals and monitoring signals to meet the special requirements of complex communication systems. Non-standard control signals and monitoring signals generally refer to signals that do not conform to the LIN, CAN, or CAN FD protocol standards, including but not limited to custom data frames, special trigger signals, debug interface signals, PWM signals, and analog or digital signals in specific environments. For example, in in-vehicle electronic systems, some intelligent sensors may use custom frame formats for data transmission, and the waveforms, frequencies, periods, and amplitudes of these frames may be different from the standard protocols. The protocol filter can match and analyze these custom frames through a preset signal feature library to achieve real-time monitoring of the device status.

[0034] Through close integration with other modules of the system, the protocol filter realizes data synchronization and timing control during signal transmission, response, and real-time monitoring, thus playing a core role in the entire electromagnetic compatibility test system. This device can not only automatically switch the working mode according to the control instructions issued by the upper computer, but also continuously read and feedback test data during the test process, making the entire test process have high real-time performance and data accuracy. In this way, it can effectively detect the performance changes of integrated circuits when they are affected by radio frequency interference, providing accurate data support for system debugging and product improvement, while significantly reducing errors and interference during signal transmission to meet the test requirements, further ensuring the stable operation of the entire test system in high-frequency, high-speed, and non-standard signal environments, and finally achieving efficient detection and data acquisition of the electromagnetic compatibility performance of integrated circuits in multiple communication protocol environments.

[0035] It should be noted that in order to evaluate the stability of the protocol filter in a complex electromagnetic environment, the system integrates electromagnetic compatibility (EMC) test procedures that comply with international standards such as ISO 7637, ISO 11452, ISO 10605, and CISPR 25. Among them, the conducted immunity test (ISO 11452-4) uses the large current injection (BCI) method to apply interference current in the frequency range of 1 MHz - 400 MHz to evaluate the communication reliability of the protocol filter under external radio frequency interference; the radiated immunity test (ISO 11452-2) verifies the anti-interference ability of the protocol filter in a strong electromagnetic environment through antenna radiation with a radio frequency field strength of 10 V / m or 30 V / m. In addition, the system also performs the transient pulse group (EFT / Burst) immunity test (ISO 7637-2) on LIN / CAN / CAN FD protocol filters, injecting a pulse group with ±2 kV and a 5 ns rise time into the power supply terminal and signal port to verify whether the device can resist the fast transient interference in automotive electronic systems. In terms of the electrostatic discharge (ESD) test, according to the ISO10605 standard, the test platform uses air discharge (±15 kV) and contact discharge (±8 kV) methods to simulate the electrostatic shocks that may be encountered inside the vehicle, ensuring that the protocol filter will not cause communication errors or functional failures due to ESD effects. In addition to the immunity test, the system also performs electromagnetic interference (EMI) evaluation to ensure that the protocol filter will not cause electromagnetic pollution to surrounding devices. According to the CISPR 25 standard, the conducted emission test is used to measure the electromagnetic noise of the protocol filter on the power line and data bus in the frequency band of 150 kHz - 108 MHz to evaluate its conducted interference level, while the radiated emission test measures the electromagnetic radiation in the range of 30 MHz - 1 GHz to ensure that the radiation level of the protocol filter will not affect in-vehicle wireless communication devices. In addition, to further verify the power supply robustness of the protocol filter, the system also performs load dump (ISO 7637-2) and voltage dip test (ISO16750-2), simulating the situation of sudden changes in automotive power supply voltage (such as +40 V surge or voltage drop to 6 V), ensuring that the protocol filter will not cause abnormal reset or damage due to power supply fluctuations. This test procedure is achieved through the collaborative work of an interference signal injection device, an isolated communication device, and a high-speed oscilloscope. The interference signal injection device consists of a programmable signal generator and a power amplifier, which is responsible for generating standardized electromagnetic interference signals in the immunity test and applying them to the power line and data bus of the protocol filter through direct current coupling or antenna radiation; in the radiation and conducted emission tests, the interference signal injection device monitors the electromagnetic emission level of the protocol filter in real time through a high-speed data acquisition module and transmits the data to the host computer for analysis.The isolation communication device uses optical fiber transmission to ensure that the test system is not affected by common ground interference. The optoelectronic conversion module uses a laser protocol filter and supports data transmission at a rate of 1 Gbps, enabling the oscilloscope to record LIN / CAN / CAN FD communication waveforms and interference signals with a time resolution of 10 ns, so as to capture signal distortion and transient anomalies caused by interference. The host computer is equipped with professional protocol analysis software, which calculates the bit error rate and frame loss rate in real time during the test process, and establishes a correlation curve between the interference intensity and the communication bit error rate through data fitting.

[0036] In summary, by integrating a standardized EMC test process, this system can comprehensively evaluate the working performance of CAN / LIN protocol filters in a complex electromagnetic environment. It can not only accurately measure the immunity and electromagnetic emission characteristics of devices, but also capture transient anomalies through high-precision waveform analysis to ensure the reliability of protocol filters in automotive electronics and industrial applications.

[0037] Embodiment 2 of this application provides an electromagnetic compatibility test system with a dual isolation communication device, as Figure 2 FIG. is a schematic structural diagram of the electromagnetic compatibility test system with a dual isolation communication device provided in this Embodiment 2. The isolation communication device of the electromagnetic compatibility test system with a dual isolation communication device includes a first isolation communication device and a second isolation communication device. The first isolation communication device communicates with the second isolation communication device through optical fiber. The first isolation communication device is electrically connected to the test board, and the second isolation communication device is electrically connected to the oscilloscope and the host computer respectively; The first isolation communication device is used to convert the electrical signal sent by the test board into an optical signal and perform long-distance transmission through optical fiber; The second isolation communication device is used to convert the optical signal transmitted by the first isolation communication device back into an electrical signal and send the electrical signal to the oscilloscope and the host computer respectively.

[0038] Specifically, the first isolation communication device is electrically connected to the test board. A high-performance laser emission module is integrated within this device. Its main function is to receive the electrical signals output by the test board, perform necessary preprocessing and modulation on these signals, and then convert the electrical signals into optical signals through laser communication technology. The laser communication technology adopted is based on a high-speed laser, which can quickly respond to changes in input signals, thus ensuring the precise retention of key parameters such as timing and amplitude during the signal conversion process. Moreover, when the laser signal is transmitted in the optical fiber, it has extremely low attenuation and extremely high anti-interference ability. In this way, even in a complex electromagnetic environment, it can ensure that the signal is not interfered with during long-distance transmission. At the same time, the second isolation communication device is electrically connected to the oscilloscope and the upper computer. A high-sensitivity photoelectric receiving module is integrated inside it. The main task of this module is to convert the optical signal transmitted through the optical fiber from the first isolation communication device back into an electrical signal, and perform signal amplification and filtering during the conversion process to ensure that the converted electrical signal maintains high-fidelity and low-noise characteristics. The converted signal is then respectively transmitted to the oscilloscope and the upper computer for real-time monitoring of the signal waveform and data acquisition and analysis.

[0039] Through the above configuration, the entire isolation communication device achieves complete electrical isolation between the test board and the upper computer and the oscilloscope. This isolation not only effectively prevents electromagnetic interference and ground potential difference problems caused by direct electrical connection, but also significantly improves the stability and security of data transmission by using the laser communication technology of optical fiber transmission. As a result, the test system can maintain excellent performance in a complex electromagnetic compatibility environment. With the support of laser communication technology, the isolation communication device in this embodiment makes the conversion process between electrical signals and optical signals more precise and fast, avoiding the response delay and transmission errors that may exist in traditional optocouplers. At the same time, long-distance data transmission is achieved through optical fiber transmission, thus meeting the strict requirements of modern integrated circuit electromagnetic compatibility testing for data transmission accuracy and anti-interference ability. In an optional implementation manner of this embodiment, the test board includes a first node and a second node. The first node and the second node are respectively connected to the first isolation communication device through a power supply interface, a control signal interface, and a monitoring signal interface. The power supply interface includes a power supply and GND. The power supply is used for the first isolation communication device to supply power to the test board; the GND interface is the common ground of the test board and the first isolation communication device, which is used to maintain a consistent signal potential reference. The control signal interface includes, but is not limited to, the TXD interface, the EN / WAKE interface, and other signal interfaces that can be customized by the upper computer software, and is used for the first isolation communication device to send control and data signals to the test board. The monitoring signal interface includes, but is not limited to, the RXD interface, the INH interface, and other signal interfaces that can be customized by the host computer software, and is used for the test board to send working status and data signals to the first isolation communication device.

[0040] Specifically, the test board includes a first node A and a second node B, which are respectively connected to the first isolation communication device through dedicated interfaces, thus constituting a complete electromagnetic compatibility test system. Among them, the power supply interface, the control signal interface, and the monitoring signal interface together realize the functions of power supply, instruction transmission, and status feedback in the system. The power supply interface between the test board and the first isolation communication device includes a power supply and GND. The power supply is used to provide a stable DC voltage to the test board, while the GND interface serves as a common ground to ensure a consistent potential reference between the test board and the first isolation communication device, thereby reducing the risk of signal distortion caused by potential drift or interference. At the same time, the control signal interface includes the TXD interface, the EN / WAKE interface, and other signal interfaces that can be customized by the host computer software. This interface is responsible for sending control instructions and data signals from the first isolation communication device to the test board, enabling the host computer to accurately control the startup, sleep, and other working states of the test board through the first isolation communication device, thereby realizing the real-time management and adjustment of the working state of the test board. The monitoring signal interface includes the RXD interface, the INH interface, and other signal interfaces that can also be customized by the host computer software. This interface is used to feedback the working status information and data signals collected during the operation of the test board to the first isolation communication device, enabling the host computer to monitor the status and data changes of the test board in real time. This embodiment realizes the stable power transmission between the test board and the first isolation communication device through the power supply interface, and constitutes a two-way communication channel through the control signal interface and the monitoring signal interface. The control signal interface is mainly used for the host computer to issue operation instructions, and then the first isolation communication device converts these instructions into electrical signals and transmits them to the test board, thereby driving the test board to perform predetermined tests or operations. The monitoring signal interface transmits the feedback signals generated during the execution of the test board back to the first isolation communication device, and then the host computer collects and records these data, thus forming a complete set of closed-loop feedback mechanisms. This mechanism can reflect the working status and data changes of the test board in the electromagnetic compatibility test in real time, ensuring the controllability and accuracy of the test process. Through the close cooperation of the above interfaces, this embodiment not only ensures the stable power supply and accurate signal transmission of the test board in different working states, but also realizes the two-way data interaction between the test board and the host computer, making the entire electromagnetic compatibility test process more efficient and reliable, reducing the risk of misjudgment caused by unstable signals, and thus having obvious application value and beneficial effects in the field of integrated circuit electromagnetic compatibility testing.

[0041] An electromagnetic compatibility test system for integrated circuits, components or vehicles provided by the solution of the present application, including an interference signal injection or reception device, a test board, an oscilloscope, a host computer, a power supply and an isolation communication device; the interference signal injection or reception device is electrically connected to the test board, and the isolation communication device is electrically connected to the test board, the oscilloscope, the host computer and the power supply respectively; the interference signal injection or reception device is used to send control signals and monitoring signals to the test board or receive the return data of the test board; the test board is used to perform electromagnetic compatibility tests according to the control signals and monitoring signals; the isolation communication device is used to perform optoelectronic conversion on the control signals and monitoring signals to form optoelectronic isolation; the oscilloscope is used to monitor the signal waveforms of the control signals and monitoring signals; the host computer is used to control the test process and collect the test data corresponding to the control signals and monitoring signals. Through the implementation of the solution of the present application, the electrical connections between the test board and the host computer and the oscilloscope are cut off through the isolation communication device, and interferences such as ground loops and common-mode noises are eliminated, ensuring that the test board is not affected by the outside during the electromagnetic compatibility test and improving the accuracy of the electromagnetic compatibility test.

[0042] As described above, the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments or equivalently replace some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present application.

Claims

1. An electromagnetic compatibility test system for integrated circuits, components or complete vehicles, characterized in that: include: Interference signal injection or receiving device, test board, oscilloscope, host computer, power supply and isolated communication device; The interference signal injection or receiving device is respectively connected to the test board and the host computer, and the isolation communication device is respectively electrically connected to the test board, the oscilloscope, the host computer and the power supply; The interference signal injection or receiving device is used to send a quantitative interference signal to the test board or receive and measure the size of the interference signal of the test board, and use a signal generator and a power amplifier to generate radio frequency interference energy during injection; and use a spectrum measurement receiver to receive the radio frequency energy of the test board during reception; The test board is used to carry the integrated circuit under test and perform electromagnetic compatibility testing according to the working state specified by the host computer; The isolated communication device is used to perform photoelectric conversion on the control signal and monitoring signal corresponding to the electromagnetic compatibility test to form photoelectric isolation; The oscilloscope is used to measure the waveform of the monitoring signal; The host computer is used to control the test process and analyze the monitoring signal to determine the test result.

2. The electromagnetic compatibility test system for integrated circuits, components or complete vehicles according to claim 1, characterized in that: The isolated communication device includes a mode controller, a code pattern analyzer, a code pattern generator, an isolator and a power isolation management module; The mode controller is used to configure the LIN / CAN / CAN FD communication mode according to the test requirements; The pattern analyzer is used to monitor and analyze LIN / CAN / CAN FD bus data in real time and detect whether there are any abnormalities in the communication process; The pattern generator is used to send standardized LIN / CAN / CAN FD data frames and definable test signals; The isolator is used to convert electrical signals into optical signals by using laser communication technology and transmit them over long distances through optical fibers to achieve photoelectric isolation; The power isolation management module is used to provide a stable power supply for the isolated communication device.

3. The electromagnetic compatibility test system for integrated circuits, components or complete vehicles according to claim 2, characterized in that: The mode controller includes a monitoring mode control unit and an excitation mode control unit; The monitoring mode control unit is used to detect the test status and read the test results, and feed back the test results to the upper computer; The excitation mode control unit is used to switch different working modes according to the control instructions sent by the host computer and control signal transmission.

4. The electromagnetic compatibility test system for integrated circuits, components or complete vehicles according to claim 2, characterized in that: The code analyzer and the code generator include a protocol filter supporting LIN / CAN / CAN FD and a coupling and decoupling network for control signals and monitoring signals; the code analyzer and the code generator distinguish different working modes through the upper computer software configuration.

5. The electromagnetic compatibility test system for integrated circuits, components or complete vehicles according to claim 2, characterized in that: The power isolation management module includes a power supply with a decoupling network.

6. The electromagnetic compatibility test system for integrated circuits, components or complete vehicles according to claim 4, characterized in that: The protocol filter is used to send and / or respond to the control signal and monitoring signal according to a preset program; the control signal and monitoring signal include communication test signals using LIN frames, CAN frames, CAN FD frames as carriers, as well as non-standard control signals and monitoring signals.

7. The electromagnetic compatibility test system for integrated circuits, components or complete vehicles according to claim 1, characterized in that: The isolated communication device includes a first isolated communication device and a second isolated communication device, the first isolated communication device and the second isolated communication device communicate with each other through optical fiber, the first isolated communication device is electrically connected to the test board, and the second isolated communication device is electrically connected to the oscilloscope and the host computer respectively; The first isolated communication device is used to convert the electrical signal sent by the test board into an optical signal and transmit it over a long distance through the optical fiber; The second isolation communication device is used to convert the optical signal transmitted by the first isolation communication device back into the electrical signal, and send the electrical signal to the oscilloscope and the host computer respectively.

8. The electromagnetic compatibility test system for integrated circuits, components or complete vehicles according to claim 1, characterized in that: The test board includes a first node and a second node, and the first node and the second node are respectively connected to the first isolation communication device through a power interface, a control signal interface and a monitoring signal interface; The power interface includes a power supply and a GND, wherein the power supply is used for the first isolated communication device to supply power to the test board; the GND interface is a common ground between the test board and the first isolated communication device, and is used to maintain a consistent signal potential reference; The control signal interface includes but is not limited to a TXD interface, an EN / WAKE interface, and other signal interfaces that can be customized by the host computer software, and is used for the first isolation communication device to send control and data signals to the test board; The monitoring signal interface includes but is not limited to an RXD interface, an INH interface and other signal interfaces that can be customized by the host computer software, and is used for the test board to send working status and data signals to the first isolation communication device.

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