Testing device, testing method and electronic equipment
By using operational amplifiers and processors to detect changes in the complex impedance of signal lines, the problem of high accuracy and high cost in detecting micro-short circuits in signal lines in electronic devices has been solved, thereby improving safety and reliability.
Patent Information
- Application Number
- CN202410637571.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-21
- Publication Date
- 2025-11-21
AI Technical Summary
Micro-short circuits in signal lines of electronic devices result in minute impedance changes. Existing detection methods require high precision and are costly, making it difficult to effectively prevent signal line abnormalities and safety hazards.
A testing device is used to detect changes in the complex impedance of the signal line through an operational amplifier and a processor. The state of the signal line is determined by the comparison signal output by the operational amplifier, thereby reducing the accuracy requirements of the test and taking preventive measures.
It improves the safety and reliability of electronic devices, reduces testing costs, and enables early detection of minor anomalies in signal lines, allowing for preventative measures to avoid short circuits.
Smart Images
Figure CN120993264A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of circuit technology, and in particular to a testing device, testing method, and electronic device. Background Technology
[0002] Currently, the density of signal lines in electronic devices is increasing. If the printed circuit board (PCB) or structural components are defective, it may cause short circuits in the signal lines of the electronic device, resulting in abnormal signal levels and thus causing the electronic device to malfunction. It may even cause local circuit overheating and create safety hazards.
[0003] Taking a power signal line as an example, to detect whether a short circuit has occurred on the power signal line, a separate sampling signal can be added to the power network. By detecting the impedance of the power signal line, it can be determined whether the impedance of the power signal line is abnormal. However, the impedance of a signal line is usually in the ohm range, while the impedance change is in the milliohm range when a micro-short circuit occurs. This measurement method requires high measurement accuracy from the measuring devices, resulting in a high testing cost. Summary of the Invention
[0004] This application provides a testing device, testing method, and electronic device that can determine the operating state of the signal line under test based on the comparison signal output by the operational amplifier, and take preventive measures when the operating state of the signal line under test changes, thereby improving the safety and reliability of the electronic device.
[0005] To achieve the above objectives, the embodiments of this application adopt the following technical solutions.
[0006] In a first aspect, embodiments of this application provide a testing apparatus for testing a signal line under test. The testing apparatus includes a power supply terminal, an operational amplifier, and a processor. The power supply terminal is coupled to the signal line under test, and the signal line under test is also coupled to a first input terminal of the operational amplifier. A second input terminal of the operational amplifier is coupled to the power supply terminal, and the output terminal of the operational amplifier is coupled to the processor. The power supply terminal is used to acquire an AC signal, the operational amplifier is used to obtain a comparison signal based on the AC signal input to the first and second input terminals, and the processor is used to determine the operating state of the signal line under test based on the comparison signal.
[0007] Therefore, in the testing apparatus provided in this application embodiment, if the operating state of the signal line under test changes, and the AC signal input to the first input terminal and the AC signal input to the second input terminal of the operational amplifier are different, the operational amplifier will output different comparison signals. The processor can then determine that the operating state of the signal line under test has changed based on the comparison signals output by the operational amplifier. Thus, even if a minor abnormality occurs in the signal line under test, the processor can detect it in advance and take measures (such as limiting current) to prevent potential problems, thereby improving the safety and reliability of the electronic equipment. Furthermore, the testing apparatus used in this application embodiment has low requirements for testing accuracy; low-precision components can be used, which can reduce testing costs.
[0008] In one possible design, the operating states of the signal line under test include a normal state and a slightly short-circuited state. The complex impedance of the signal line under test differs between the normal state and the slightly short-circuited state. The different complex impedances correspond to different AC signals, which the operational amplifier can use to obtain a comparison signal. The processor can then identify the operating state of the signal line under test and detect whether any abnormalities have occurred.
[0009] In one possible design, the processor is specifically used to: determine that the signal line under test is in a normal state when the comparison signal is at a first level; and determine that the signal line under test is in a micro-short-circuit state when the comparison signal is at a second level.
[0010] In one possible design, the amplitude of the AC signal increases by a preset increment within each preset period.
[0011] In one possible design, the processor is specifically used to determine the operating state of the signal line under test based on comparison signals of multiple preset periods. Since the micro-short circuit of the signal line under test is a slowly changing process, by sampling comparison signals of multiple preset periods, the operating state of the signal line under test can be determined based on the changing pattern of the comparison signal levels, thereby improving the accuracy of the test results from the testing device.
[0012] In one possible design, the test setup also includes a reference signal line coupled to a power supply terminal and further coupled to the second input terminal of an operational amplifier. Thus, the operational amplifier can output a comparison signal based on the AC signal from the reference signal line and the AC signal from the signal under test. Since the complex impedance of the reference signal line remains constant, adding a reference signal line reduces the test variables of the test setup, further improving the accuracy of the test results.
[0013] In one possible design, the test device further includes a first capacitor and a second capacitor; the first terminal of the first capacitor is coupled to the signal line under test, and the second terminal of the first capacitor is coupled to the first input terminal of the operational amplifier; the first terminal of the second capacitor is coupled to the reference signal line, and the second terminal of the second capacitor is coupled to the second input terminal of the operational amplifier. Thus, the test device can effectively separate AC and DC signals through the first and second capacitors, acting as a filter and further improving the accuracy of the test results.
[0014] In one possible design, the signal line under test is a signal line in a through-axis flexible printed circuit board.
[0015] Secondly, embodiments of this application also provide a testing method applied to a testing device for testing a signal line under test. The testing device includes a power supply terminal, an operational amplifier, and a processor. The power supply terminal is coupled to the signal line under test, and the signal line under test is also coupled to a first input terminal of the operational amplifier. The second input terminal of the operational amplifier is coupled to the power supply terminal, and the output terminal of the operational amplifier is coupled to the processor. The method includes: the power supply terminal acquiring an AC signal; the operational amplifier obtaining a comparison signal based on the AC signals input to the first and second input terminals respectively; and the processor determining the operating state of the signal line under test based on the comparison signal.
[0016] In one possible design, the operating states of the signal line under test include a normal state and a micro-short-circuit state, wherein the complex impedance of the signal line under test in the normal state is different from that in the micro-short-circuit state.
[0017] In one possible design, the processor determines the operating state of the signal line under test based on a comparison signal, including: when the comparison signal is at a first level, the processor determines that the signal line under test is in a normal state; when the comparison signal is at a second level, the processor determines that the signal line under test is in a micro-short-circuit state.
[0018] In one possible design, the amplitude of the AC signal increases by a preset increment in each preset cycle.
[0019] In one possible design, the processor determines the operating state of the signal line under test based on comparison signals, including: the processor determines the operating state of the signal line under test based on comparison signals of multiple preset periods.
[0020] In one possible design, the test setup also includes a reference signal line coupled to a power supply terminal and also coupled to the second input terminal of an operational amplifier.
[0021] In one possible design, the test apparatus also includes a first capacitor and a second capacitor, with the first terminal of the first capacitor coupled to the signal line under test and the second terminal of the first capacitor coupled to the first input terminal of the operational amplifier.
[0022] In one possible design, the signal line under test is a signal line in a through-axis flexible printed circuit board.
[0023] For the benefits of the second aspect, please refer to the explanation of the first aspect.
[0024] Thirdly, embodiments of this application also provide an electronic device, which includes: a motherboard, a sub-board, a through-axis flexible printed circuit board, and a testing device as described in the first aspect. The motherboard and the sub-board are coupled through the through-axis printed circuit board, and the testing device is disposed on the motherboard or the sub-board. The testing device is used to test a signal line under test, which is a signal line in the through-axis flexible printed circuit board.
[0025] Fourthly, embodiments of this application also provide another electronic device, which includes a processor and a memory storing instructions that, when executed by the processor, cause the electronic device to perform the methods provided by the second aspect or any possible implementation thereof.
[0026] Fifthly, embodiments of this application provide a computer-readable storage medium including computer instructions that, when executed on an electronic device, cause the electronic device to perform the test method in any of the possible implementations of the second aspect described above.
[0027] In a sixth aspect, embodiments of this application provide a computer program product that, when run on a computer or processor, causes the computer or processor to execute the test method in any of the possible implementations of the second aspect described above.
[0028] It is understood that any of the testing devices, electronic devices, computer-readable storage media or computer program products provided above can be applied to the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can be referred to the beneficial effects in the corresponding testing devices, which will not be repeated here.
[0029] These or other aspects of this application will become more readily apparent in the following description. Attached Figure Description
[0030] Figure 1 This is a schematic diagram of the structure of a foldable screen system provided in an embodiment of this application;
[0031] Figure 2 An equivalent schematic diagram of a first resistor, a second resistor, and a return path provided for an embodiment of this application;
[0032] Figure 3 This is a schematic diagram of the structure of a testing device provided in an embodiment of this application;
[0033] Figure 4 A waveform diagram of an AC signal provided in an embodiment of this application;
[0034] Figure 5 This is a schematic diagram of another testing device provided in an embodiment of this application;
[0035] Figure 6 A flowchart of a testing method provided in an embodiment of this application. Detailed Implementation
[0036] For ease of understanding, the examples provide explanations of some concepts related to the embodiments of this application for reference. As shown below:
[0037] 1. Inter-integrated circuit (I2C) bus: A bus used to connect microcontrollers and their peripherals. The I2C bus consists of two lines: serial data (SDA) and serial clock (SCL). SDA and SCL transmit messages between devices connected to the I2C bus. Each device connected to the bus can be assigned an address via a unique address and a simple master / slave relationship software. The master can act as a master transmitter or a master receiver.
[0038] 2. Mobile Industry Processor Interface (MIPI): An open standard and specification for mobile application processors initiated by the MIPI Alliance. It standardizes the interfaces inside mobile devices, such as cameras, displays, baseband, and radio frequency interfaces, thereby increasing design flexibility while reducing costs, design complexity, and power consumption.
[0039] 3. General-purpose input / output (GPIO): Some pins of the chip can be freely used by the user through the program. Depending on the practical considerations, the pins can be used as general-purpose input (GPI), general-purpose output (GPO), or GPIO.
[0040] 4. Serial Peripheral Interface (SPI): A high-speed, full-duplex, and synchronous communication bus. SPI communication operates in a master-slave mode, involving one master device and one or more slave devices, requiring at least four lines. These four lines are common to all SPI-based devices: Master Input Slave Output (MISO), Master Output Slave Input (MOSI), Serial Clock (SCLK), and Chip Select (CS). MISO is the master data input and the slave data output. MOSI is the master data output and the slave data input. The CS signal is the slave enable signal, controlling whether the slave device is selected by the master. The SCLK signal is the clock pulse provided by the master device; MISO and MOSI use this clock pulse to complete data transmission.
[0041] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. In the description of the embodiments of this application, unless otherwise stated, " / " means "or," for example, A / B can mean A or B; "and / or" in this text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, in the description of the embodiments of this application, "multiple" refers to two or more than two.
[0042] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this embodiment, unless otherwise stated, "a plurality of" means two or more.
[0043] Currently, an increasing number of electronic devices are using foldable screens for their display panels. These devices typically consist of a motherboard and a sub-board, with signals transmitted between them via a through-axis flexible printed circuit board (FPC). During use, the through-axis FPC is repeatedly folded, and the signal lines on it can become worn and malfunction. When a signal line in the through-axis FPC short-circuits to the frame of the electronic device, a large current will be generated, causing the through-axis FPC to burn out.
[0044] The wear process of through-shaft FPCs is a long-term process. When a micro-short circuit occurs in the signal line of an through-shaft FPC, the impedance change of the signal line is within a few milliohms. Since the impedance of the signal line is on the order of ohms, the impedance change is on the order of milliohms, which is a small change, and the electronic device may still be in normal working condition at this time. However, if no measures are taken to solve the micro-short circuit problem, the through-shaft FPC is likely to deteriorate from a micro-short circuit to a short circuit, leading to irreversible consequences.
[0045] To address the issue of micro-short circuits in signal lines of through-shaft FPCs, a measurement method for these signal lines is proposed. For example... Figure 1 As shown, Figure 1 This is a schematic diagram of a foldable screen system provided in an embodiment of this application. The foldable screen system includes a motherboard and a sub-board, which are coupled together via a through-axis FPC. The signal lines on the through-axis FPC may include an internal integrated bus (I2C), a mobile industry processor interface (MIPI), and general purpose input / output (GPIO). In addition, the through-axis FPC also includes return paths, which include system voltage (VSYS) and ground (GND).
[0046] Specifically, the motherboard also includes a first resistor, with its first end coupled to the VSYS signal line on the motherboard side and its second end coupled to the VSYS signal line in the through-axis FPC. The secondary board also includes a second resistor, with its first end coupled to the load on the secondary board and its second end coupled to the GND signal line in the FPC. The motherboard may also include a power management unit (PMU), which can collect the current at the first end of the first resistor (current detection -) and the current at the second end of the first resistor (current detection +) to determine if there is an abnormally high current on the secondary board. Alternatively, the power management unit can also be located on the secondary board side, for example, by placing a third resistor on the secondary board side. Figure 1 (Not shown in the diagram), the first terminal of the third resistor is coupled to the VSYS signal line in the FPC, and the second terminal of the third resistor is coupled to the VSYS signal line in the sub-board. The power management unit can collect the current across the third resistor to determine if there is an abnormally large current on the sub-board.
[0047] Additionally, the sub-board may include a thermistor, whose resistance changes with temperature. When there is an abnormally high current on the sub-board, the thermistor's resistance will change, and the power management unit can read the thermistor's resistance to determine if there is an abnormally high current on the sub-board.
[0048] The equivalent schematic diagram of the first resistor, the second resistor, and the return path is shown below. Figure 2 As shown, Figure 2R1 in the middle is Figure 1 The first resistor in the middle, Figure 2 R2 in the middle is Figure 1 The second resistor in Figure 2 R3 in the middle is Figure 1 The equivalent resistance of the VSYS signal line in the through-shaft FPC. Among them, the first end of R1 is coupled to VSYS, the second end of R1 is coupled to the first end of R3, the second end of R3 is coupled to the first end of R2, and the second end of R2 is grounded.
[0049] Assuming R1 = 2Ω, R2 = 2Ω, and R3 = 2Ω when not slightly short-circuited, and its resistance between 2.002Ω and 2.01Ω when slightly short-circuited. In this case, when the resistance of R3 changes by 0.002Ω, the proportion of the resistance change for the entire circuit is 0.0003. Assuming the analog-to-digital converter (ADC) in the power management unit has a resolution of 12 bits and a reference voltage of 1.8V, the ADC resolution is 1.8 / 2. 12 =0.0004. In other words, when the resistance change is 0.0003 when a micro-short circuit occurs in the signal line of the through-shaft FPC, the analog-to-digital converter cannot detect the change and therefore cannot meet the measurement accuracy requirements.
[0050] Therefore, this application provides a testing device including a power supply, an operational amplifier, and a processor. The testing device can test the operating state of a signal line under test. If the operating state of the signal line under test changes, the AC signal input to the first input terminal and the AC signal input to the second input terminal of the operational amplifier will differ, and the operational amplifier will output different comparison signals. The processor can then determine that the operating state of the signal line under test has changed based on the comparison signals output by the operational amplifier. Thus, even if a minor abnormality occurs in the signal line under test, the processor can detect it in advance and take measures (such as limiting current) to prevent potential problems, thereby improving the safety and reliability of electronic equipment. Furthermore, the testing device used in this application has low requirements for testing accuracy; low-precision components can be used, reducing testing costs.
[0051] In the above scenario, the testing device provided in this application embodiment can be applied to electronic devices, such as mobile phones, tablets, desktops, laptops, handheld computers, notebook computers, ultra-mobile personal computers (UMPCs), netbooks, cellular phones, personal digital assistants (PDAs), augmented reality (AR) / virtual reality (VR) devices, etc. This application embodiment does not impose any special restrictions on the specific form of the electronic device.
[0052] In some embodiments, the testing apparatus provided in this application can be applied to the aforementioned electronic device. The electronic device, including a foldable screen, may include a motherboard and a sub-board. The testing apparatus can be disposed on the motherboard or on the sub-board. In one example, the testing apparatus can test the operating status of signal lines coupled to a through-axis flexible printed circuit board between the motherboard and the sub-board.
[0053] In this embodiment, the foldable screen can be a type of flexible screen. In some embodiments, the foldable screen can be folded along a first direction, or the foldable screen can be folded along a second direction, wherein the first direction and the second direction are perpendicular.
[0054] The testing apparatus provided in the embodiments of this application will be further described below.
[0055] This application provides a testing device that can be used to test signal lines under test, such as... Figure 3 As shown, Figure 3 This is a schematic diagram of a testing device provided in an embodiment of this application. The testing device includes a power supply terminal ( Figure 3 (represented by VREF), operational amplifier and processor, power supply and the signal line under test are coupled, the signal line under test is also coupled to the first input terminal of the operational amplifier (VREF). Figure 3 The second input terminal of the operational amplifier (represented by input terminal "a") is coupled. Figure 3 The input terminal (represented by "b") is coupled to the power supply terminal, and the output terminal of the operational amplifier (… Figure 3 The operational amplifier (represented by the output terminal "c") is coupled to the processor. It can transmit signals to the processor via I2C or SPI bus.
[0056] The signal line under test can be a single-ended transmission line, a differential transmission line, a microstrip line, or a stripline. Taking a single-ended transmission line as an example, the impedance is related to its size, dielectric layer thickness, and dielectric constant. Specifically, the impedance of a single-ended transmission line is inversely proportional to its height and width, inversely proportional to its dielectric layer thickness, and inversely proportional to the square root of its dielectric constant.
[0057] Optionally, the signal line to be tested can be a signal line in a through-shaft FPC.
[0058] For example, a through-axis FPC can be applied to an electronic device including a foldable screen system, which may include a motherboard and a sub-board. The through-axis FPC can be used to transmit signals between the motherboard and the sub-board. The testing device can test the power signal lines in the through-axis FPC, and the testing device can also test other signal lines in the through-axis FPC.
[0059] For example, a switch can be placed between the signal line under test and the power supply terminal. In one example, the switch can be an N-type metal oxide semiconductor (NMOS). When there are multiple signal lines under test, the on or off state of the switch can be used to control the on or off state of the currently tested signal line and the power supply terminal.
[0060] Because electronic devices, including foldable screen systems, are repeatedly folded during use, the signal lines in the through-axis FPC are prone to wear and tear, which may lead to short circuits with the mid-frame and cause abnormal signal line operation. The testing device provided in this application embodiment can test the operating status of the signal lines in the through-axis FPC, detect abnormalities in the signal lines in advance, and take measures such as limiting current to avoid short circuits, thereby improving the safety and reliability of electronic devices, including foldable screen systems.
[0061] The power supply end can be used to acquire AC signals.
[0062] For example, an AC signal is a signal whose amplitude and direction change over time, such as a sine wave signal and a cosine wave signal.
[0063] For example, the power supply terminal can be coupled to an AC power supply circuit. Specifically, the AC power supply circuit can include an inverter, a filter, a control circuit, and an output terminal. The inverter can be used to convert a DC signal into an AC signal with different frequencies, amplitudes, and phases. The inverter can be a transformer or electronic device (such as a transistor or integrated circuit). The filter can remove unwanted frequency components from the AC signal; the filter can be a low-pass filter or a high-pass filter. The control circuit can be used to control and regulate the DC-to-AC signal conversion process. For example, the control circuit can adjust the frequency, amplitude, and phase of the AC signal as needed to meet specific application requirements. The output terminal can be coupled to the power supply terminal to output an AC signal to the power supply terminal.
[0064] The operational amplifier is used to obtain a comparison signal based on the AC signals input to the first and second input terminals, respectively.
[0065] For example, an operational amplifier (OA) is a high-gain, differential-input, DC-coupled electronic amplifier typically used to amplify and process analog signals, but it can also be used as a comparator. When an operational amplifier is used as a comparator, it compares two input signals and outputs a high- or low-level digital signal to represent the relative magnitude of the two input signals.
[0066] Specifically, when the voltage values at the non-inverting and inverting input terminals of the operational amplifier are the same, the operational amplifier outputs 0V; when the voltage value at the non-inverting input terminal is greater than the voltage value at the inverting input terminal, the operational amplifier outputs a high level; and when the voltage value at the non-inverting input terminal is less than the voltage value at the inverting input terminal, the operational amplifier outputs a low level. The high-level voltage is close to the positive power supply voltage of the operational amplifier, and the low-level voltage is close to the negative power supply voltage. Furthermore, because the open-circuit gain of the operational amplifier is very large, even a slight difference between the signals at the two input terminals can be compared.
[0067] In other words, even if there is a slight difference between the AC signal input to the first input terminal and the AC signal input to the second input terminal, the operational amplifier can detect this slight difference and output a comparison signal. The first input terminal can be a non-inverting input terminal, and the second input terminal can be an inverting input terminal. Alternatively, the first input terminal can also be an inverting input terminal, and the second input terminal can also be a non-inverting input terminal.
[0068] For example, the operational amplifier can compare the amplitude of the AC signal at the first input terminal and the amplitude of the AC signal at the second input terminal to obtain a comparison signal. In one example, assuming the difference between the two AC signals is less than or equal to a preset threshold, it indicates that the amplitudes of the two AC signals are substantially the same, and the comparison signal can be low. Assuming the difference between the two AC signals is greater than the preset threshold, it indicates that the amplitudes of the two AC signals are substantially different, and the comparison signal can be high. The preset threshold can be determined by those skilled in the art based on measurement experience.
[0069] The processor is used to determine the operating state of the signal line under test based on the comparison signal.
[0070] For example, the processor can be a central processing unit (CPU), but it can also be other types of processors, such as a single-core processor or a multi-core processor. After loading data and applications from memory, the processor processes the data, for example, determining the operating state of the signal line under test based on a comparison signal in this embodiment. When the processor detects an abnormality in the signal line under test, it can take measures (such as limiting current) to prevent short circuits and other problems, thereby improving the safety and reliability of the electronic device.
[0071] Optionally, the operating states of the signal line under test include normal state and micro-short-circuit state. The complex impedance of the signal line under test in the normal state is different from that in the micro-short-circuit state. The micro-short-circuit state is relative to the short-circuit state. If the signal line under test is in the short-circuit state, it can be understood that the impedance of the signal line under test is less than 1 milliohm; if the signal line under test is in the micro-short-circuit state, it can be understood that the change in impedance of the signal line under test relative to the normal state is within a few milliohms.
[0072] In one example, assuming the operational amplifier operates at 1MHz and the parasitic capacitance of the signal line under test is 40pF, then when the signal line under test is in normal condition, the complex impedance of the signal line under test is:
[0073] In one example, assuming the operational amplifier operates at 1MHz and the parasitic capacitance of the signal line under test is 40pF, then when the signal line under test is in a slightly short-circuited state, its equivalent resistance is 2Ω. Therefore, the complex impedance of the signal line under test... In other words, compared to the complex impedance of the signal line under test in its normal state, the rate of change of the complex impedance of the signal line under test when a micro-short circuit occurs reaches 2000 times. Therefore, the change in complex impedance can be used to determine whether a micro-short circuit has occurred in the signal line under test.
[0074] For example, if the signal line under test is in a normal state, since both the first and second input terminals of the operational amplifier are coupled to the power supply, the voltage values of the AC signals at the first and second input terminals of the operational amplifier are the same. In this case, the comparison signal of the operational amplifier can be low. If the signal line under test is in a slightly short-circuited state, since the complex impedance of the signal line under test changes significantly in the slightly short-circuited state, the voltage values of the AC signals at the first and second input terminals of the operational amplifier are different. In this case, the comparison signal of the operational amplifier can be high.
[0075] Optionally, the processor is specifically used to: determine that the signal line under test is in a normal state when the comparison signal is at the first level; and determine that the signal line under test is in a micro-short-circuit state when the comparison signal is at the second level.
[0076] For example, the first voltage level can be high and the second voltage level can be low. Alternatively, the first voltage level can be low and the second voltage level can be high.
[0077] Taking a low level as the first level and a high level as the second level, and considering that the operational amplifier outputs a low level when the signals at the non-inverting input and the inverting input are the same, and a high level when they are different, the signal under test is normal when the comparison signal is low (i.e., the AC signals at the first and second inputs of the operational amplifier are the same). When the comparison signal is high (i.e., the AC signals at the first and second inputs of the operational amplifier are different), the signal under test is abnormal and is in a slightly short-circuited state.
[0078] Optionally, the amplitude of the AC signal increases by a preset increment within each preset period.
[0079] In one example, the waveform of an AC signal can be as follows: Figure 4 As shown, Figure 4 This is a waveform diagram of an AC signal provided in an embodiment of this application. Figure 4 The figure shows the amplitude of the AC signal as it changes over time, where the preset period can be 1µs and the preset increment can be 0.2V. Specifically, at the 1µs mark, the amplitude of the AC signal is 0.4V, at the 2µs mark, the amplitude of the AC signal is 0.6V, and so on, with the amplitude of the AC signal increasing by 0.2V every 1µs. Figure 4 The waveform diagram of the AC signal in the embodiment is only an example, and the embodiments of this application do not specifically limit the waveform of the AC signal.
[0080] Optionally, the processor is specifically used to determine the operating state of the signal line under test based on comparison signals of multiple preset periods.
[0081] Continue reading Figure 4Since the power supply receives an AC signal, the sampling levels at the non-inverting and inverting inputs of the operational amplifier differ in each preset cycle. Furthermore, because the impedance changes significantly when a micro-short circuit occurs in the signal line under test, the sampling levels at the non-inverting and inverting inputs also differ in each preset cycle. Therefore, the micro-short circuit in the signal line under test is a slowly changing process. By sampling for several preset cycles, it can be determined that the change pattern of the comparison signal level output by the operational amplifier differs, thus determining whether a short circuit has occurred in the signal line under test.
[0082] Optional, such as Figure 5 As shown, Figure 5 This is a schematic diagram of another test apparatus provided in an embodiment of this application. The test apparatus may further include a reference signal line, which is coupled to a power supply terminal and also to the second input terminal of an operational amplifier. Figure 5 (The input terminal "b" indicates coupling).
[0083] in, Figure 5 The diagram also shows the parasitic capacitance C1 and equivalent resistance R1 of the signal line under test, as well as the parasitic capacitance C2 of the reference signal line. The parasitic capacitance C1 and equivalent resistance R1 are connected in parallel.
[0084] In some embodiments, the reference signal line can be understood as a signal line whose impedance does not change, and the capacitance value of the parasitic capacitance C2 of the reference signal line can be the same as the capacitance value of the parasitic capacitance C1 of the signal line under test.
[0085] For example, when the signal line under test is in a normal state, no such phenomenon will occur. Figure 5 In the normal state, the equivalent resistance R1 of the signal line under test and the reference signal line both have parasitic capacitances. This means the comparator signal output by the operational amplifier is not affected by the equivalent resistance R1, resulting in a substantial difference. However, when the signal line under test is in a slightly short-circuited state, the equivalent resistance R1 and the parasitic capacitance C1 are connected in parallel, causing a significant change in the complex impedance compared to the normal state. Therefore, the comparator signal output by the operational amplifier is affected by the equivalent resistance R1, resulting in a substantial difference.
[0086] In addition, adding a reference signal line can reduce the test variables of the test device and further improve the accuracy of the test results.
[0087] Continue reading Figure 5 The testing device may also include a first capacitor C3 and a second capacitor C4, with the first terminal of the first capacitor ( Figure 5 The input terminal "d" is used to couple the signal line under test, and the second terminal of the first capacitor ( Figure 5 The input terminal is indicated by "e" and the first input terminal of the operational amplifier ( Figure 5The input terminal "a" is used for coupling. The first terminal of the second capacitor ( Figure 5 The input terminal "f" is coupled to the reference signal line, and the second terminal of the second capacitor ( Figure 5 The second input terminal of the operational amplifier is represented by the input terminal "g". Figure 5 (In Chinese, the input terminal "b" is used to represent this).
[0088] For example, the first and second capacitors can be "DC-blocking and AC-passing" capacitors, meaning they can pass AC signals while blocking DC signals. Taking the first capacitor as an example, when an AC signal passes through it, it generates an electric field between the two electrodes, causing the charges in the capacitor to move back and forth between the positive and negative electrodes. Therefore, the AC signal can pass through the first capacitor. However, for DC signals, due to the properties of the dielectric material in the first capacitor, a polarized charge is generated between the two electrodes, preventing the charges in the first capacitor from moving. Therefore, the DC signal cannot pass through the first capacitor.
[0089] Therefore, the first and second capacitors can effectively separate AC and DC signals, playing a filtering role and further improving the accuracy of the test results of the test device.
[0090] The testing method provided in the embodiments of this application is described below, using the aforementioned testing apparatus.
[0091] like Figure 6 As shown, Figure 6 A flowchart of a testing method provided in an embodiment of this application is shown, the method including the following steps.
[0092] S601, obtain AC signal from the power supply end.
[0093] S602, the operational amplifier obtains a comparison signal based on the AC signals input to the first input terminal and the second input terminal respectively.
[0094] S603: The processor determines the operating status of the signal line under test based on the comparison signal.
[0095] For example, the testing device can acquire AC signals through a power supply. Since the input signal of the operational amplifier is an AC signal, when the operating state of the operational amplifier changes, the complex impedance of the signal line under test changes significantly. That is, the AC signal input to the first input terminal and the AC signal input to the second input terminal of the operational amplifier are different. As a result, the comparison signals output by the operational amplifier are different, and the processor can compare the signals to determine that the operating state of the signal line under test has changed. Therefore, even if a minor abnormality occurs in the signal line under test, the processor can detect it in advance and take measures (such as limiting current) to prevent potential problems, thereby improving the safety and reliability of electronic equipment. In addition, the testing device used in this embodiment has low requirements for testing accuracy, and low-precision components can be used, which can reduce testing costs.
[0096] Optionally, S603 may include: when the comparison signal is at a first level, the processor determines that the signal line under test is in a normal state; when the comparison signal is at a second level, the processor determines that the signal line under test is in a micro-short-circuit state.
[0097] For example, the first level and the second level can be different levels, and the processor can determine the operating state of the signal line under test based on the comparison signal of different levels.
[0098] Optionally, S603 may include: the processor determining the operating state of the signal line under test based on comparison signals of multiple preset periods.
[0099] For example, the micro-short circuit of the signal line under test is a slowly changing process. By sampling for several preset periods, it can be determined that the level of the comparison signal output by the operational amplifier changes differently, which can also determine whether a short circuit has occurred in the signal line under test.
[0100] This application also provides an electronic device, which includes a motherboard, a sub-board, a through-axis flexible printed circuit board, and a testing device. The motherboard and the sub-board are coupled through the through-axis printed circuit board. The testing device is disposed on the motherboard or the sub-board and is used to test the signal line under test, which is a signal line in the through-axis flexible printed circuit board.
[0101] This application also provides another electronic device, which includes a processor and a memory, the memory storing instructions that, when executed by the processor, cause the electronic device to perform a test method.
[0102] Embodiments of this application also provide a computer storage medium storing computer instructions. When the computer instructions are executed on an electronic device, the electronic device performs the aforementioned related method steps to implement the testing method in the above embodiments.
[0103] Embodiments of this application also provide a computer program product that, when run on a computer, causes the computer to perform the aforementioned related steps to implement the testing method executed by the electronic device in the above embodiments.
[0104] In addition, embodiments of this application also provide an apparatus, which may specifically be a chip, component, or module. The apparatus may include a connected processor and a memory; wherein the memory is used to store computer execution instructions, and when the apparatus is running, the processor may execute the computer execution instructions stored in the memory to cause the chip to execute the test methods executed by the electronic devices in the above-described method embodiments.
[0105] In this embodiment, the testing device, electronic device, computer storage medium, computer program product or chip are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can be referred to the beneficial effects of the corresponding methods provided above, and will not be repeated here.
[0106] Through the above description of the embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.
[0107] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.
[0108] The units described as separate components may or may not be physically separate. A component shown as a unit can be one or more physical units; that is, it can be located in one place or distributed in multiple different locations. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0109] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.
[0110] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solutions of the embodiments of this application, essentially or in other words, the parts that contribute to the prior art, or all or part of the technical solutions, can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0111] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A test device, characterized by The test device is used for testing a to-be-tested signal line, and the test device comprises a power supply end, an operational amplifier and a processor; the power supply end and the to-be-tested signal line are coupled, the to-be-tested signal line is further coupled with a first input end of the operational amplifier, a second input end of the operational amplifier is coupled with the power supply end, and an output end of the operational amplifier is coupled with the processor; the power supply end is used for acquiring an alternating current signal; the operational amplifier is used for obtaining a comparison signal based on alternating current signals input by the first input end and the second input end respectively; the processor is used for determining a working state of the to-be-tested signal line based on the comparison signal.
2. The test device of claim 1, wherein, The working state of the to-be-tested signal line comprises a normal state and a micro-short circuit state, wherein a complex impedance of the to-be-tested signal line in the normal state is different from a complex impedance of the to-be-tested signal line in the micro-short circuit state.
3. The test device of claim 2, wherein, The processor is specifically used for: determining that the to-be-tested signal line is in the normal state when the comparison signal is a first level; determining that the to-be-tested signal line is in the micro-short circuit state when the comparison signal is a second level.
4. The test device according to any one of claims 1 to 3, characterized in that An amplitude of the alternating current signal increases by a preset increment in each preset period.
5. The test device of claim 4, wherein, The processor is specifically used for: determining the working state of the to-be-tested signal line according to the comparison signals of multiple preset periods.
6. The test device of any one of claims 1-5, wherein, The test device further comprises a reference signal line, the reference signal line is coupled with the power supply end, and the reference signal line is further coupled with the second input end of the operational amplifier.
7. The test device of claim 6, wherein, The test device further comprises a first capacitor and a second capacitor; a first end of the first capacitor is coupled with the to-be-tested signal line, and a second end of the first capacitor is coupled with the first input end of the operational amplifier; a first end of the second capacitor is coupled with the reference signal line, and a second end of the second capacitor is coupled with the second input end of the operational amplifier.
8. The test device according to any one of claims 1 to 7, wherein, The to-be-tested signal line is a signal line in a through-axis flexible printed circuit board.
9. A test method characterized by, The method is applied to a test device, the test device is used for testing a to-be-tested signal line, and the test device comprises a power supply end, an operational amplifier and a processor, the power supply end and the to-be-tested signal line are coupled, the to-be-tested signal line is further coupled with a first input end of the operational amplifier, a second input end of the operational amplifier is coupled with the power supply end, and an output end of the operational amplifier is coupled with the processor; the method comprises the following steps: the power supply end acquires an alternating current signal; the operational amplifier obtains a comparison signal based on alternating current signals input by the first input end and the second input end respectively; the processor determines a working state of the to-be-tested signal line based on the comparison signal.
10. The test method of claim 9, wherein, The working state of the to-be-tested signal line comprises a normal state and a micro-short circuit state, wherein a complex impedance of the to-be-tested signal line in the normal state is different from a complex impedance of the to-be-tested signal line in the micro-short circuit state.
11. The test method of claim 10, wherein, The processor determines the working state of the to-be-tested signal line based on the comparison signal, and the determination comprises the following steps: when the comparison signal is a first level, the processor determines that the to-be-tested signal line is in the normal state; when the comparison signal is a second level, the processor determines that the to-be-tested signal line is in the micro-short circuit state. When the comparison signal is at the second level, the processor determines that the signal line under test is in the micro-short-circuit state.
12. The test method according to any one of claims 9-11, characterized in that, The amplitude of the AC signal increases by a preset increment in each preset period.
13. The test method of claim 12, wherein, The processor determines the operating state of the signal line under test based on the comparison signal, including: The processor determines the operating state of the signal line under test based on the comparison signals of multiple preset periods.
14. The test method according to any one of claims 9-13, characterized in that, The test apparatus also includes a reference signal line, which is coupled to the power supply terminal and also coupled to the second input terminal of the operational amplifier.
15. The test method of claim 14, wherein, The testing device also includes a first capacitor and a second capacitor; The first terminal of the first capacitor is coupled to the signal line under test, and the second terminal of the first capacitor is coupled to the first input terminal of the operational amplifier. The first terminal of the second capacitor is coupled to the reference signal line, and the second terminal of the second capacitor is coupled to the second input terminal of the operational amplifier.
16. The test method according to any one of claims 9-15, characterized in that, The signal line under test is a signal line in a through-axis flexible printed circuit board.
17. An electronic device, comprising: The electronic device includes: a motherboard, a sub-board, a through-axis flexible printed circuit board, and a testing device as described in any one of claims 1-8, wherein the motherboard and the sub-board are coupled through the through-axis flexible printed circuit board, the testing device is disposed on the motherboard or the sub-board, and the testing device is used to test a signal line under test, wherein the signal line under test is a signal line in the through-axis flexible printed circuit board.
18. A computer-readable storage medium, characterized in that, Includes computer instructions that, when executed on an electronic device, cause the electronic device to perform the method described in any one of claims 9-16.