Test tool

Abstract

The embodiment of the utility model relates to the field of switching power supply testing, and provides a testing tool comprising a power supply circuit used for providing a first power supply voltage and a second power supply voltage; the main control circuit is connected with the upper computer and the power supply circuit, and the main control circuit is used for receiving the first power supply voltage to work, responding to a control instruction sent by the upper computer, and generating and outputting a PWM (Pulse Width Modulation) signal; the load switch circuit is provided with a load end and a grounding end, one end of the load end is connected with the load resistor, the other end of the load end is used for being connected with the positive electrode of the switching power supply, and the grounding end is used for being connected with the negative electrode of the switching power supply; and in response to the PWM signal, the load end and the grounding end are alternately cut off or conducted through the load resistor. According to the embodiment of the invention, the test cost and the operation difficulty can be reduced at least, test application scenes are increased, the test accuracy is improved, and resource waste is avoided.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to the field of switching power supply testing, and in particular to a testing tool. Background Art

[0002] The load transient test is a rapid method for examining the performance of a switching power supply. It can reveal the power supply's regulation speed, quickly assessing its stability and speed, and highlighting stability issues. This test can also quickly reveal issues with the power supply's load regulation characteristics, input voltage stability, slope compensation, and PCB (Printed Circuit Board) layout. When selecting a switching power supply chip, load transient test performance is often a crucial factor in evaluating the chip's dynamic performance.

[0003] In the related art, an electronic load is usually used to perform a load transient test to complete a load transient performance test of a switching power supply. However, there are certain problems in using an electronic load to perform a load transient performance test of a switching power supply. Utility Model Content

[0004] The embodiments of the present disclosure provide a testing tool that can at least reduce testing costs and operational difficulty, increase testing application scenarios, and improve testing accuracy without causing waste of resources.

[0005] According to some embodiments of the present disclosure, on the one hand, an embodiment of the present disclosure provides a load transient performance test tool for a switching power supply, the test tool comprising: a power supply circuit, the power supply circuit being used to provide a first power supply voltage and a second power supply voltage; a main control circuit, the main control circuit being connected to a host computer and the power supply circuit, the main control circuit being used to receive the first power supply voltage to operate, and in response to a control instruction sent from the host computer, to generate and output a PWM (Pulse-width modulation) signal; a load switch circuit, the load switch circuit having a load terminal and a ground terminal, wherein one end of the load terminal is connected to a load resistor, and the other end is used to connect to the positive pole of the switching power supply, and the ground terminal is used to connect to the negative pole of the switching power supply, the load switch circuit receives the second power supply voltage, and responds to the PWM signal to alternately cut off the load terminal and the ground terminal or to conduct through the load resistor.

[0006] In some embodiments, the first supply voltage is equal to the second supply voltage, and the power supply circuit includes: a USB interface, the USB interface is used to connect the input power supply, the USB interface is also used to connect the host computer, and the host computer is connected to the main control circuit through the USB interface; a first step-down module, the first step-down module is connected to the USB interface, and the first step-down module is used to reduce the input power supply to the first supply voltage.

[0007] In some embodiments, the first supply voltage is not equal to the second supply voltage, and the power supply circuit includes: a USB interface, which is used to connect the input power supply, and the USB interface is also used to connect the host computer, and the host computer is connected to the main control circuit through the USB interface; a first step-down module, which is connected to the USB interface and is used to reduce the input power supply to the first supply voltage; and a second step-down module, which is connected to the USB interface and is used to reduce the input power supply to the second supply voltage.

[0008] In some embodiments, the testing tool further includes: a communication module, wherein the communication module is connected to the main control circuit and is used for the main control circuit to communicate with the host computer.

[0009] In some embodiments, the communication module includes: a USIM card socket, which is connected to the main control circuit and is used to register a cellular network for the main control circuit; and a radio frequency antenna, which is connected to the main control circuit and is used to receive or send cellular network signals registered by the main control circuit; wherein the host computer realizes communication connection with the main control circuit through the cellular network.

[0010] In some embodiments, the load switch circuit includes: a MOS transistor, the gate of the MOS transistor is connected to the main control circuit, one of the source or drain of the MOS transistor is connected to the load resistor, and the other of the source or drain of the MOS transistor is used to connect to the negative electrode of the switching power supply; a drive circuit, the drive circuit is connected between the main control circuit and the gate of the MOS transistor, and is used to receive the PWM signal and amplify the PWM signal. The drive circuit is also used to transmit the amplified PWM signal to the gate of the MOS transistor.

[0011] In some embodiments, the main control circuit is a 4G module.

[0012] In some embodiments, the load switch circuit includes: a resistance control module, the resistance control module is connected to the host computer and the load resistor, and the host computer adjusts the resistance value of the load resistor through the resistance control module.

[0013] In some embodiments, the testing tool further includes: a power button, which is used to turn the main control circuit on or off; and a reset button, which is used to reset and restart the main control circuit.

[0014] In some embodiments, the testing tool further includes: a collector, which is used to collect the output current and output voltage of the switching power supply.

[0015] The technical solution provided by the embodiments of the present disclosure has at least the following advantages:

[0016] In the technical solution of the test tool provided by the embodiment of the present disclosure, the test tool includes: a power supply circuit, a main control circuit and a load switch circuit, the power supply circuit is used to provide a first supply voltage and a second supply voltage; the main control circuit is connected to a host computer and the power supply circuit, the main control circuit is used to receive the first supply voltage to work, and in response to a control instruction sent from the host computer, generate and output a PWM signal; the load switch circuit has a load terminal and a ground terminal, wherein one end of the load terminal is connected to a load resistor, the other end is used to connect to the positive terminal of the switching power supply, and the ground terminal is used to connect to the negative terminal of the switching power supply, the load switch circuit receives the second supply voltage and responds to the PWM signal to alternately cut off the load terminal and the ground terminal or conduct through the load resistor. In the test tool provided by the present application, the main control circuit responds to the control instruction sent from the host computer to generate and output the PWM signal to the load switch circuit, the load switch circuit is connected to the switching power supply, and responds to the PWM signal to alternately cut off the load terminal and the ground terminal or conduct through the load resistor to achieve load state switching of the switching power supply between no-load and full-load, so as to meet the conditions for load transient performance testing of the switching power supply. The main control circuit in the test tool can be connected to a host computer, and the host computer sends a response instruction to complete the load state switching of the switching power supply. Compared with using an electronic load machine to test the load transient performance of the switching power supply, the operation difficulty is lower. The test tool provided by the present application includes a power supply circuit, a main control circuit, and a load switching circuit. The fewer components included make the cost of the test tool provided by the present application smaller, thereby reducing the testing cost. The power supply circuit, main control circuit, and load switching circuit in the test tool provided by the present application can be integrated on a PCB board, thereby making the test tool more portable.

[0017] In addition, the test tool provided by the present application contains fewer components, so that the volume of the test tool can be smaller. It can also complete the load transient performance test of the switching power supply for some test scenarios with limited space. Compared with the larger electronic load machine, it has more test application scenarios. In addition, the test tool provided by the present application is small in size. When connecting the load switch circuit to the switching power supply, a shorter connecting wire can be used, thereby avoiding the influence of the loop inductance caused by the long connecting wire on the test, and improving the accuracy of the test. The test tool provided by the present application is specifically used to measure the load transient performance of the switching power supply, so that resources will not be wasted due to excess performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] One or more embodiments are exemplarily illustrated by the pictures in the corresponding drawings. These exemplified descriptions do not constitute a limitation on the embodiments. Unless otherwise stated, the pictures in the drawings do not constitute a scale limitation. In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the traditional technology, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 A schematic diagram of the structure of a testing tool provided in an embodiment of the present disclosure;

[0020] Figure 2 A schematic diagram of the structure of another testing tool provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0021] Testing the load transient performance of switching power supplies is typically performed using an electronic load meter. However, current electronic load meters are generally expensive, making them difficult to purchase for budget-constrained users, resulting in a high test cost. Functionality: Testing only rapid load transitions does not require extensive parameter configuration or high test accuracy. However, due to their integrated testing functions, electronic load meters often have complex user interfaces, requiring specialized knowledge and operational skills. This can create a learning curve for those who don't frequently use the instrument. Furthermore, for applications solely focused on load transient performance, excessive performance can be wasteful. Size: Electronic load meters are typically large and occupy a considerable amount of space, which can be inconvenient in space-constrained test environments, limiting their applicability. Regarding test performance, testing load transients with electronic load meters typically requires connecting cables to the switching power supply module. Long cables introduce significant loop inductance, affecting test results and reducing accuracy.

[0022] In summary, the testing cost and operation difficulty of the load transient performance of power switches in related technologies are high, the test application scenarios are limited, the test accuracy is low and it is easy to waste resources.

[0023] The present disclosure provides a test tool. In the test tool provided by the present application, a main control circuit responds to a control instruction sent from a host computer to generate and output a PWM signal to a load switch circuit. The load switch circuit is connected to a switching power supply and responds to the PWM signal to alternately cut off the load terminal and the ground terminal or conduct through the load resistor to achieve load state switching of the switching power supply between no-load and full-load, thereby meeting the conditions for testing the load transient performance of the switching power supply. The main control circuit in the test tool can be connected to the host computer, and the host computer sends a response instruction to complete the load state switching of the switching power supply. Compared with using an electronic load device to test the load transient performance of the switching power supply, the operation difficulty is lower. The test tool provided by the present application includes a power supply circuit, a main control circuit, and a load switch circuit. The fewer components included make the cost of the test tool provided by the present application lower, thereby reducing testing costs. The power supply circuit, main control circuit, and load switch circuit in the test tool provided by the present application can be integrated on a PCB board, making the test tool more portable.

[0024] In addition, the test tool provided by the present application contains fewer components, so that the volume of the test tool can be smaller. It can also complete the load transient performance test of the switching power supply for some test scenarios with limited space. Compared with the larger electronic load machine, it has more test application scenarios. In addition, the test tool provided by the present application is small in size. When connecting the load switch circuit to the switching power supply, a shorter connecting wire can be used, thereby avoiding the influence of the loop inductance caused by the long connecting wire on the test, and improving the accuracy of the test. The test tool provided by the present application is specifically used to measure the load transient performance of the switching power supply, so that resources will not be wasted due to excess performance.

[0025] The following describes various embodiments of the present disclosure in detail with reference to the accompanying drawings. However, those skilled in the art will appreciate that many technical details are provided in the various embodiments of the present disclosure to facilitate a better understanding of the present disclosure. However, even without these technical details and the various variations and modifications based on the following embodiments, the technical solutions claimed in the present disclosure can still be implemented.

[0026] Figure 1 A schematic diagram of the structure of a testing tool provided in an embodiment of the present disclosure.

[0027] refer to Figure 1The test tool includes: a power supply circuit 100, a main control circuit 101 and a load switch circuit 102, the power supply circuit 100 is used to provide a first power supply voltage and a second power supply voltage; the main control circuit 101 is connected to the host computer and the power supply circuit 100, the main control circuit 101 is used to receive the first power supply voltage to work, and generate and output a PWM signal in response to a control instruction sent from the host computer; the load switch circuit 102 has a load terminal 112 and a ground terminal 122, wherein one end of the load terminal 112 is connected to the load resistor 103, and the other end is used to connect to the positive electrode of the switching power supply (not shown), and the ground terminal 122 is used to connect to the negative electrode of the switching power supply (not shown), the load switch circuit 102 receives the second power supply voltage, and responds to the PWM signal to alternately cut off the load terminal 112 and the ground terminal 122 or conduct through the load resistor 103.

[0028] The test tool is used to test the load transient performance of the switching power supply.

[0029] A switching power supply can be a DC-DC switching power supply. A DC-DC switching power supply is a power supply device that converts direct current into different voltage levels. It controls the input voltage of the power supply by using switching elements (such as transistors or MOSFETs) at high frequencies, and achieves voltage conversion and filtering through components such as transformers, inductors, and capacitors. DC-DC switching power supplies offer advantages such as high efficiency, small size, light weight, and excellent stability. They are widely used in electronic devices and power supply systems, providing a stable and reliable power supply for various electronic devices.

[0030] The power supply circuit 100 is used to supply power to the main control circuit 101 and the load switch circuit 102. Specifically, the power supply circuit 100 is used to provide a first power supply voltage to the main control circuit 101 so that the main control circuit 101 can operate normally, and the power supply circuit 100 is used to provide a second power supply voltage to the load switch circuit 102 so that the load switch circuit 102 can operate normally.

[0031] In some embodiments, the power supply circuit 100 includes a USB interface 110 and a first step-down module 120. The first step-down module 120 is connected to the USB interface 110 and is used to step down the input power to a first supply voltage and supply power to the main control circuit 101. The first step-down module 120 is also electrically connected to the load switch circuit 102 to provide a second supply voltage for the load switch circuit 102. The first supply voltage is equal to the second supply voltage.

[0032] The USB interface 110 is used to connect the input power supply and the host computer, so that the main control circuit 101 can be connected to the host computer. The host computer can send control instructions to the main control circuit 101 through the USB interface 110 to control the main control circuit 101 to generate and output PWM signals.

[0033] The host computer can be a PC (personal computer), or a mobile phone, tablet, workstation, server, Raspberry Pi, or any other device with communication and human-computer interaction functions.

[0034] The first step-down module 120 is used to step down the input power connected to the USB interface 110 to a first supply voltage. When the first supply voltage is equal to the second supply voltage, the power supply circuit 100 can operate both the main control circuit 101 and the load switch circuit 102 normally using only the first step-down module 120, thereby simplifying the structure of the test tool and reducing the cost of the test tool.

[0035] In a specific example, the input power voltage is 5 V, the first supply voltage is equal to the second supply voltage, and the second supply voltage is equal to 3.8 V. It will be understood that the input power voltage and the values ​​of the first supply voltage and the second supply voltage are provided for illustrative purposes only, and the values ​​of the first supply voltage and the second supply voltage can be adaptively adjusted and set according to actual application conditions, and the embodiments of the present disclosure are not limited thereto.

[0036] The main control circuit 101 is used to connect to a host computer, and generate and output a PWM signal in response to a control instruction sent from the host computer.

[0037] In some embodiments, the main control circuit 101 may include a PWM interface 111, and the main control circuit 101 sends a PWM signal to the load switch circuit 102 through the PWM interface 111. The host computer can use a language to write a program script to initialize the PWM interface 111. The host computer can also configure an appropriate PWM frequency and duty cycle according to the application scenario, and then send control instructions to the main control circuit 101 through the USB interface 110 to control the opening and closing of the PWM signal.

[0038] In some embodiments, the main control circuit 101 may be a 4G module. The 4G module has a high transmission speed and uses advanced signal processing technology, which can effectively avoid problems such as signal interference and packet loss, ensuring the stability and reliability of data transmission. The 4G module also has the characteristics of low power consumption. Compared with the previous 2G and 3G modules, the 4G module can better optimize power consumption when transmitting data and extend battery life. Therefore, using a 4G module as the main control circuit 101 can improve the practicality of the test tool.

[0039] In other examples, the main control circuit 101 may also be a 2G module, a 3G module, or a 5G module.

[0040] The load switch circuit 102 is used to connect the switching power supply to be tested. Specifically, the load switch circuit 102 has a load terminal 112 and a ground terminal 122. One end of the load terminal 112 is connected to the load resistor 103, and the other end is used to connect to the positive electrode of the switching power supply. The ground terminal 122 is used to connect to the negative electrode of the switching power supply. The load switch circuit 102 responds to the PWM signal to alternately cut off the load terminal 112 and the ground terminal 122 or to conduct through the load resistor 103 to achieve load state switching between no-load and full-load of the switching power supply.

[0041] In some embodiments, the load switch circuit 102 may include a MOS transistor 132 and a driver circuit 142. The gate of the MOS transistor 132 is connected to the main control circuit 101, one of the source or drain of the MOS transistor 132 is connected to the load resistor 103, and the other of the source or drain of the MOS transistor 132 is connected to the negative electrode of the switching power supply. The driver circuit 142 is connected between the main control circuit 101 and the gate of the MOS transistor 132 and is configured to receive and amplify a PWM signal. The driver circuit 142 is also configured to transmit the amplified PWM signal to the gate of the MOS transistor 132. With this configuration, the MOS transistor 132 can receive the PWM signal to alternately cut off the load terminal 112 and the ground terminal 122, or conduct the signal through the load resistor 103, thereby achieving load state switching between no-load and full-load states of the switching power supply. Using the driver circuit 142 to amplify the PWM signal can enhance the driving capability of the PWM signal output by the main control circuit 101, enabling the MOS transistor 132 to have faster turn-on and turn-off speeds, thereby meeting the fast load switching requirements of the switching power supply.

[0042] In a specific example, the MOS transistor 132 can be an NMOS transistor, the drain of the MOS transistor 132 is connected to the load resistor 103, and the source of the MOS transistor is connected to the negative electrode of the switching power supply. When the PWM signal is a high-level pulse width, the gate-source voltage V GS Can be greater than the threshold voltage V of MOS tube 132 TH When the PWM signal is low, the drain and source paths of the MOS transistor 132 are connected, and then the positive electrode of the switching power supply passes through the load resistor 103 and the gate and source of the MOS transistor 132 to the negative electrode of the switching power supply, forming a current loop, and the switching power supply is in a loaded state (also called a full-load state). When the PWM signal is a low-level pulse width, the drain and source paths of the MOS transistor 132 are cut off, and the current loop between the positive and negative electrodes of the switching power supply is disconnected, and the switching power supply is in a no-load state (also called a no-load state). This process is repeated, and the switching power supply is always in a periodic switching between no-load and loaded states.

[0043] It should be noted that when the PWM signal has a low pulse width, theoretically, the drain and source paths of the MOS transistor 132 are cut off. In practice, leakage current may exist in the MOS transistor 132, causing a certain current to exist between the positive and negative electrodes of the switching power supply. At this time, the switching power supply is in a relatively low load state. When the PWM signal switches between a high pulse width and a low pulse width, the switching power supply is in a periodic switching between a relatively low load state and a loaded state, which can still meet the conditions for the load transient performance test of the switching power supply.

[0044] In some embodiments, the load switch circuit 102 may include a resistance control module (not shown), which is connected to a host computer and the load resistor 103. The host computer adjusts the resistance of the load resistor 103 through the resistance control module. This configuration allows the resistance of the load resistor to be changed, thereby changing the maximum output current of the load terminal 112. This allows the user to adjust the resistance of the load resistor 103 through the host computer according to actual needs to meet the testing requirements of the switching power supply in different situations, thereby improving the practicality of the testing tool.

[0045] In some embodiments, load resistor 103 may include multiple packaged chip resistors of different resistance values, or load resistor 103 may include a replaceable high-power metal film through-hole resistor. Before using the test tool, the user can replace the resistors in load resistor 103 to adjust the resistance value of load resistor 103 according to test requirements, and can also adjust the maximum output current of load terminal 112, thereby improving the practicality of the test tool.

[0046] In some embodiments, the test tool further includes a communication module 104, which is connected to the main control circuit 101 and is used to communicate between the main control circuit 101 and a host computer. In this configuration, the host computer can remotely control the main control circuit 101 through the communication module 104, which is conducive to improving the practicality of the test tool.

[0047] In some embodiments, the communication module 104 may include: a USIM card holder 114 and a radio frequency antenna 124, the USIM card holder 114 is connected to the main control circuit 101, and is used to register the main control circuit 101 with a cellular network; the radio frequency antenna 124 is connected to the main control circuit 101, and is used to receive or send signals from the cellular network registered by the main control circuit 101; wherein, the upper computer realizes communication connection with the main control circuit 101 through the cellular network.

[0048] The USIM card holder 114 can be used to hold a USIM card to register the main control circuit 101 with a cellular network. The RF antenna 124 is used to receive or transmit signals from the cellular network registered with the main control circuit 101. Because cellular networks have wide signal coverage and strong signal transmission capabilities, using a cellular network to achieve communication between the host computer and the main control circuit 101 is beneficial for improving the efficiency and reliability of signal transmission when the host computer and the main control circuit 101 are remotely connected.

[0049] In some embodiments, the test tool further includes a power button 105 and a reset button 106. The power button 105 is used to turn the main control circuit 101 on or off, and the reset button 106 is used to reset and restart the main control circuit 101. With this arrangement, a tester can turn the main control circuit 101 on or off using the power button 105 and reset and restart the main control circuit 101 using the reset button 106, thereby improving the practicality of the test tool.

[0050] In some embodiments, the test tool further includes a data collector (not shown) configured to collect the output current and output voltage of the switching power supply. When the load switch circuit 102 responds to a PWM signal to alternately cut off the load terminal 112 from the ground terminal 122 or conduct it via the load resistor 103, thereby switching the switching power supply between no-load and full-load states, the data collector collects the output current and output voltage of the switching power supply to complete the load transient performance test of the switching power supply.

[0051] It should be noted that the test tool may not include the aforementioned collector. When the load switch circuit 102 responds to the PWM signal to alternately cut off the load terminal 112 and the ground terminal 122, or conduct electricity via the load resistor 103, thereby switching the switching power supply between no-load and full-load states, the output current and output voltage of the switching power supply can be tested using an external test instrument, such as a voltmeter, multimeter, or oscilloscope, to complete the load transient performance test of the switching power supply. In addition, when using an oscilloscope to collect voltage data from the switching power supply, an oscilloscope probe can also be used to measure the output capacitance of the switching power supply. Because the output capacitance at the output end of the switching power supply has a filtering effect, using the oscilloscope probe to measure both ends of the output capacitance when collecting voltage data can minimize external noise interference and improve test accuracy.

[0052] In some embodiments, the test tool may include a PCB board, and the power supply circuit 100, the main control circuit 101, and the load switch circuit 102 may be arranged on the PCB board and electrically connected. Such an arrangement may improve the portability of the test tool.

[0053] Figure 2 A schematic structural diagram of another testing tool provided in an embodiment of the present disclosure.

[0054] refer to Figure 2 In some embodiments, the first supply voltage may not be equal to the second supply voltage. In this case, the power supply circuit 200 includes: a USB interface 210, a first step-down module 220, and a second step-down module 230. The USB interface 210 is used to connect the input power supply. The USB interface 210 is also used to connect to the host computer, and the host computer is connected to the main control circuit 201 through the USB interface 210; the first step-down module 220 is connected to the USB interface 210, and the first step-down module 220 is used to reduce the input power supply to the first supply voltage; the second step-down module 230 is connected to the USB interface 210, and the second step-down module 230 is used to reduce the input power supply to the second supply voltage.

[0055] The first step-down module 220 is used to step down the input power connected to the USB interface 210 to a first supply voltage, and the second step-down module 230 is used to step down the input power to a second supply voltage. When the first supply voltage is not equal to the second supply voltage, in order to ensure that the main control circuit 201 and the load switch circuit 202 can operate normally, the first step-down module 220 and the second step-down module 230 are required to step down the input power, thereby improving the reliability of the operation of the test tool.

[0056] It should be noted that the power supply circuit 200, the main control circuit 201, the load switch circuit 202, the USB interface 210, the PWM interface 211, the load end 212, the ground end 222, the MOS tube 232, the drive circuit 242, the communication module 204, the USIM card holder 214, the RF antenna 224, the power button 205, and the reset button 206 of the embodiment of the present disclosure can refer to the corresponding descriptions of the power supply circuit 100, the main control circuit 101, the load switch circuit 102, the USB interface 110, the PWM interface 111, the load end 112, the ground end 122, the MOS tube 132, the drive circuit 142, the communication module 104, the USIM card holder 114, the RF antenna 124, the power button 105, and the reset button 106 in the previous embodiment, and will not be repeated here.

[0057] In the above-mentioned test tool, the main control circuit responds to the control command sent from the host computer to generate and output a PWM signal to the load switch circuit. The load switch circuit is connected to the switching power supply and responds to the PWM signal to alternately cut off the load terminal and the ground terminal or conduct through the load resistor to achieve load state switching of the switching power supply between no-load and full-load, so as to meet the conditions for the load transient performance test of the switching power supply. The main control circuit in the test tool can be connected to the host computer, and the host computer sends a response command to complete the load state switching of the switching power supply. Compared with the load transient performance test of the switching power supply using an electronic load machine, the operation difficulty is lower. The test tool provided by this application includes a power supply circuit, a main control circuit and a load switch circuit, and includes fewer components. Fewer components make the cost of the test tool provided by this application lower, thereby reducing the testing cost. The power supply circuit, main control circuit and load switch circuit in the test tool provided by this application can be integrated on a PCB board, making the test tool more portable. In addition, the test tool provided by the present application contains fewer components, so that the volume of the test tool can be smaller. It can also complete the load transient performance test of the switching power supply for some test scenarios with limited space. Compared with the larger electronic load machine, it has more test application scenarios. In addition, the test tool provided by the present application is small in size. When connecting the load switch circuit to the switching power supply, a shorter connecting wire can be used, thereby avoiding the influence of the loop inductance caused by the long connecting wire on the test, and improving the accuracy of the test. The test tool provided by the present application is specifically used to measure the load transient performance of the switching power supply, so that resources will not be wasted due to excess performance.

[0058] Those skilled in the art will appreciate that the above-described embodiments are specific examples for implementing the present disclosure, and that in actual applications, various changes in form and detail may be made thereto without departing from the spirit and scope of the present disclosure. Any person skilled in the art may make changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be subject to the scope defined in the claims.

Claims

1. A testing tool, characterized in that: The test tool is used for load transient performance testing of a switching power supply, and the test tool comprises: a power supply circuit, the power supply circuit being configured to provide a first supply voltage and a second supply voltage; A main control circuit, the main control circuit is connected to the host computer and the power supply circuit, the main control circuit is used to receive the first power supply voltage to operate, and generate and output a PWM signal in response to a control instruction sent from the host computer; a load switch circuit, the load switch circuit has a load terminal and a ground terminal, wherein one end of the load terminal is connected to a load resistor and the other end is used to connect to the positive electrode of the switching power supply, and the ground terminal is used to connect to the negative electrode of the switching power supply, the load switch circuit receives the second power supply voltage, and responds to the PWM signal to alternately cut off the load terminal and the ground terminal or turn on through the load resistor.

2. The testing tool according to claim 1, wherein: The first supply voltage is equal to the second supply voltage, and the power supply circuit includes: A USB interface, the USB interface is used to connect to the input power supply, the USB interface is also used to connect to the host computer, and the host computer is connected to the main control circuit through the USB interface; A first step-down module is connected to the USB interface and is used to reduce the input power to the first supply voltage.

3. The testing tool according to claim 1, wherein: The first supply voltage is not equal to the second supply voltage, and the power supply circuit includes: A USB interface, the USB interface is used to connect to the input power supply, the USB interface is also used to connect to the host computer, and the host computer is connected to the main control circuit through the USB interface; a first step-down module, connected to the USB interface, and configured to reduce the input power to the first supply voltage; A second step-down module is connected to the USB interface, and the second step-down module is used to reduce the input power supply to the second supply voltage.

4. The testing tool according to claim 1, wherein: The testing tool also includes: A communication module is connected to the main control circuit and is used for communication between the main control circuit and the host computer.

5. The testing tool according to claim 4, characterized in that: The communication module includes: a USIM card holder, the USIM card holder being connected to the main control circuit and being used to register the main control circuit with a cellular network; a radio frequency antenna being connected to the main control circuit and being used to receive or transmit signals from the cellular network registered by the main control circuit; The host computer realizes communication connection with the main control circuit through the cellular network.

6. The testing tool according to claim 1, wherein: The load switch circuit comprises: a MOS transistor, wherein the gate of the MOS transistor is connected to the main control circuit, one of the source or the drain of the MOS transistor is connected to the load resistor, and the other of the source or the drain of the MOS transistor is used to connect to the negative electrode of the switching power supply; A drive circuit is connected between the main control circuit and the gate of the MOS tube, and is used to receive the PWM signal and amplify the PWM signal. The drive circuit is also used to transmit the amplified PWM signal to the gate of the MOS tube.

7. The testing tool according to claim 1, wherein: The main control circuit is a 4G module.

8. The testing tool according to claim 1, wherein: The load switch circuit comprises: A resistance control module is connected to the host computer and the load resistor, and the host computer adjusts the resistance value of the load resistor through the resistance control module.

9. The testing tool according to claim 1, wherein: The testing tool also includes: A power button, used to turn the main control circuit on or off; A reset button is used to reset and restart the main control circuit.

10. The testing tool according to any one of claims 1 to 9, characterized in that: The testing tool also includes: A collector is used to collect the output current and output voltage of the switching power supply.

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