A device testing circuit, testing power supply and testing method

Abstract

This invention discloses a device testing circuit, a testing power supply, and a testing method. The device testing circuit includes an input circuit, a power supply circuit, a control circuit, and an output circuit. The input circuit uses an input DC bus circuit to receive and distribute DC power. The power supply circuit includes multiple independent power modules, each drawing power from the input DC bus circuit. The control circuit uses a switch matrix to achieve controllable connection between multiple output interfaces of the power supply circuit and the output circuit. The output circuit is used to connect to an experimental circuit. The input DC bus circuit is a bidirectional bus for bidirectional transmission of DC power between the power supply circuit and the experimental circuit. This invention solves the technical problems of existing testing power supplies, such as large size, poor combination flexibility, and insufficient portability.

Description

Technical Field

[0001] This invention relates to the field of power supply technology for devices, and more particularly to a device test circuit, test power supply, and test method. Background Technology

[0002] During device testing, multiple power supply outputs with different voltage and current parameters are often required to evaluate device performance under various operating conditions. Existing test power supplies have the following shortcomings: First, they are bulky, typically larger than 30*20*15cm, occupying a large space and lacking portability when multiple tests are needed. Second, the multi-channel combination is fixed, making it difficult to quickly adjust the output combination according to test requirements, and changing test configurations is time-consuming, usually requiring 10-15 minutes. Third, their cascading expansion capability is limited, and the synchronization accuracy is low when multiple devices work together, affecting the consistency of test data. In particular, power supply modules in traditional test systems often adopt a fixed structure with fixed output parameters for each channel. Changing the test requires re-calibrating the wiring, which is cumbersome and inefficient. While general-purpose programmable power supplies support parameter adjustment, they lack a multi-channel rapid combination design, and it is difficult to guarantee accuracy in a compact structure. In addition, the electrical conditions of conventional experimental circuits are provided by the power supply alone, or the transmission direction is unidirectional, i.e., from the power supply side to the experimental circuit side. However, in environmental experiments involving live operation, there is often a need for bidirectional transmission, requiring transmission from the experimental side to the outside, which conventional power supplies cannot meet.

[0003] Chinese Patent Application No. CN202610121478.2 discloses an electronic device testing fixture and testing system. The electronic device testing fixture includes a sample mounting unit and a test adapter unit. The sample mounting unit includes a test piece connection part and a test signal interface, while the test adapter unit includes a signal input interface and a signal output interface. The test piece connection part is used to connect electronic devices, and the multiple test piece connection parts of the sample mounting unit are adapted to at least two different specifications of electronic devices. Multiple independent conductive paths are formed between the test adapter unit and the multiple test piece connection parts. The test adapter unit is used to transmit the test electrical signal received by the signal input interface to the electronic device mounted on the sample mounting unit. Existing technologies cannot solve the above-mentioned technical problems; therefore, there is an urgent need to propose a device testing circuit, a test power supply, and a testing method. Summary of the Invention

[0004] The main objective of this invention is to propose a device testing circuit, a testing power supply, and a testing method, aiming to solve the technical problems of existing testing power supplies being large in size, having poor combination flexibility, and lacking portability.

[0005] To achieve the above objectives, the present invention provides a device testing circuit, wherein the device testing circuit includes: an input circuit, a power supply circuit, a control circuit, and an output circuit;

[0006] The input circuit adopts an input DC bus circuit for receiving and distributing DC power;

[0007] The power supply circuit includes multiple independent power modules, each of which obtains power from the input DC bus circuit;

[0008] The control circuit achieves controllable connection between multiple output interfaces of the power supply circuit and the output circuit through a switch matrix;

[0009] The output circuit is used to connect to the experimental circuit;

[0010] The input DC bus circuit is a bidirectional bus, used for bidirectional transmission of DC power between the power supply circuit and the experimental circuit.

[0011] In one preferred embodiment, each independent power module in the power supply circuit includes:

[0012] DC input circuit, charging and discharging circuit, backup battery, independent power supply circuit, independent power supply control circuit, display circuit and DC output circuit;

[0013] The DC input circuit is connected to the charging and discharging circuit, the charging and discharging circuit is connected to the backup battery and the independent power supply circuit respectively, the independent power supply circuit is connected to the independent power supply control circuit and the DC output circuit respectively, and the independent power supply control circuit is connected to the display circuit.

[0014] The DC input circuit serves as the input port for an external DC power supply.

[0015] The charging and discharging circuit is used to manage the charging of the backup battery and to control the discharge of the backup battery when the main power is interrupted.

[0016] The independent power supply circuit is used to output DC power;

[0017] The independent power control circuit is used to monitor and set power parameters;

[0018] The display circuit is used to display power status information;

[0019] The DC output circuit serves as the final output port.

[0020] In one preferred embodiment, the independent power supply circuit includes a power charging circuit, which includes an external input DC power supply, a DC voltage regulator module, a current limiting resistor, a battery BT1, an electrical isolation circuit, and an adjustable power supply.

[0021] In one preferred embodiment, the external input DC power supply is connected to the anode of diode D6, the cathode of diode D6 is connected to the DC voltage regulator module, the cathode of diode D9, and the adjustable power supply, the DC voltage regulator module is connected to resistor R5, the other end of resistor R5 is connected to the positive terminal of battery BT1 and the anode of diode D8, the negative terminal of battery BT1 is grounded, and the cathode of diode D8 is connected to the anode of diode D9.

[0022] In one preferred embodiment, the DC voltage regulator module includes a boost circuit and a buck circuit that can be automatically switched, as well as a set of first control circuits;

[0023] The first control circuit is configured to detect the input voltage and compare it with the battery voltage. When the input voltage is lower than the battery voltage, the boost circuit is turned on and the buck circuit is turned off; when the input voltage is higher than the battery voltage, the boost circuit is turned off and the buck circuit is turned on.

[0024] The boost circuit is used to boost the input voltage that is lower than the battery voltage and stabilize the output; the buck circuit is used to buck the input voltage that is higher than the battery voltage and stabilize the output.

[0025] In one preferred embodiment, the boost circuit includes a boost chip U1, a diode D1, a capacitor C3, a diode D2, a resistor R2, a resistor R3, an inductor L1, and a capacitor C4. Pin 1 of the boost chip U1 is connected to the anode of diode D2 and inductor L1. The cathode of diode D2 is connected to resistor R2, capacitor C3, and the anode of diode D1. The cathode of diode D1 is connected to the output terminal. The other end of resistor R2 is connected to resistor R3 and pin 3 of the boost chip U1. The other end of inductor L1 is connected to pin 5 of the boost chip U1, capacitor C4, and the input terminal. The other end of pin 3 of the boost chip U1, capacitor C3, resistor R3, and capacitor C4 is grounded.

[0026] In one preferred embodiment, the step-down circuit includes a step-down chip U2, a diode D3, a capacitor C1, a resistor R1, a resistor R4, an inductor L2, a capacitor C2, and a capacitor C5. Pin 1 of the step-down chip U2 is connected to capacitor C2. The other end of capacitor C2 is connected to inductor L2 and pin 6 of the step-down chip U2. The other end of inductor L2 is connected to resistor R1, capacitor C1, and the anode of diode D3. The cathode of diode D3 is connected to the output terminal. The other end of resistor R1 is connected to resistor R4 and pin 3 of the step-down chip U2. Pin 5 of the step-down chip U2 is connected to the input terminal and capacitor C5. Pin 2 of the step-down chip U2, capacitor C1, resistor R4, and the other end of capacitor C5 are grounded.

[0027] In one preferred embodiment, the switch matrix is ​​composed of multiple bidirectional switching circuits forming an m*n switching network, where m is the number of output interfaces and n is the number of power modules.

[0028] A device test power supply, the device test power supply including the aforementioned device test circuit.

[0029] A device testing method including the aforementioned device test power supply includes the following steps:

[0030] S1. Connect the device under test to the experimental circuit, and set the output combination mode of the power module through the switch matrix of the control circuit;

[0031] S2. Set the output voltage, current parameters, and operating mode via the independent power supply front panel;

[0032] S3. Start the power supply to power the experimental circuit and monitor the output parameters in real time;

[0033] S4. After the test is completed, the energy storage element in the experimental circuit is discharged by switching the connection through the control circuit.

[0034] In the above technical solution of the present invention, the device test circuit includes: an input circuit, a power supply circuit, a control circuit, and an output circuit; the input circuit adopts an input DC bus circuit for receiving and distributing DC power; the power supply circuit includes multiple independent power modules, each of which obtains power from the input DC bus circuit; the control circuit realizes controllable connection between multiple output interfaces of the power supply circuit and the output circuit through a switch matrix; the output circuit is used to connect to the experimental circuit; wherein, the input DC bus circuit is a bidirectional bus for bidirectional transmission of DC power between the power supply circuit and the experimental circuit. The present invention solves the technical problems of existing test power supplies being large in size, having poor combination flexibility, and lacking portability.

[0035] In this invention, the test power supply adopts a compact cubic structure design with an overall size not exceeding 10cm*10cm*10cm. It possesses constant current and constant voltage dual-mode output capabilities. Through interactive control of the single-channel and output circuits, independent output adjustment of each power supply is achieved. The innovative matrix architecture and flexible connection system enable rapid independent combination of multiple outputs, greatly improving power supply utilization. The optimized power supply is widely adaptable to single-parameter testing scenarios or multi-parameter collaborative testing scenarios for various devices such as diodes, transistors, and MOSFETs, and is particularly suitable for high-precision laboratory testing and rapid production line inspection needs. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of a device testing circuit according to an embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of the switch matrix according to an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the power module according to an embodiment of the present invention;

[0040] Figure 4 This is a schematic diagram of the power supply charging circuit according to an embodiment of the present invention;

[0041] Figure 5 This is a schematic diagram of the boost circuit according to an embodiment of the present invention;

[0042] Figure 6 This is a schematic diagram of the step-down circuit according to an embodiment of the present invention;

[0043] Figure 7 This is a schematic diagram of the first control circuit according to an embodiment of the present invention;

[0044] Figure 8 This is a schematic diagram of a bidirectional switching switch according to an embodiment of the present invention;

[0045] Figure 9 This is a first schematic diagram of the device test power supply according to an embodiment of the present invention;

[0046] Figure 10 This is a second schematic diagram of the device test power supply according to an embodiment of the present invention;

[0047] Figure 11 This is a schematic diagram of a device testing method according to an embodiment of the present invention.

[0048] The realization of the objective, functional characteristics and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0051] See Figures 1-8 According to one aspect of the present invention, the present invention provides a device testing circuit, wherein the device testing circuit includes: an input circuit, a power supply circuit, a control circuit and an output circuit;

[0052] The input circuit adopts an input DC bus circuit for receiving and distributing DC power;

[0053] The power supply circuit includes multiple independent power modules, each of which obtains power from the input DC bus circuit;

[0054] The control circuit achieves controllable connection between multiple output interfaces of the power supply circuit and the output circuit through a switch matrix;

[0055] The output circuit is used to connect to the experimental circuit;

[0056] The input DC bus circuit is a bidirectional bus, used for bidirectional transmission of DC power between the power supply circuit and the experimental circuit.

[0057] Specifically, in this embodiment, the input DC bus circuit is the system DC input / power bus, powered by an AC / DC module. The AC / DC module rectifies the AC power and converts it into DC power to supply the entire power module. The AC power is converted into DC power by the AC / DC module and enters the input DC bus. Multiple parallel power modules obtain power from the input DC bus. The power modules can be DC power supplies with adjustable voltage or current, operating independently and complementing each other. Each power module corresponds to a control circuit for adjusting and managing the power supply's output parameters. The output terminals of the control circuits converge to the output bus and are connected to the experimental circuit through the output bus.

[0058] Specifically, in this embodiment, the output bus is a bidirectional bus, indicating that the transmission of electrical energy is bidirectional. It can be transmitted to the experimental circuit or from the experimental circuit to the control circuit, and the electrical energy is adjusted by the respective control circuits. The adjusted electrical energy is then collected at the output bus and supplied to the experimental circuit.

[0059] Specifically, in this embodiment, the power supply circuit provides stable and controllable DC power to the experimental circuit. The power module adopts a compact structural design, integrates constant voltage and constant current output functions, supports rapid setting and precise adjustment of voltage and current parameters, and has a built-in backup battery and an external battery expansion interface. Even in the event of a sudden power outage, the experiment can still be carried out continuously and stably. The power module is an independent power system with battery power supply capability, which can automatically switch to built-in battery power supply when the main power supply is interrupted, thereby ensuring the continuous and stable operation of the experimental circuit.

[0060] Specifically, in this embodiment, each independent power module in the power supply circuit includes: a DC input circuit, a charging and discharging circuit, a backup battery, an independent power supply circuit, an independent power control circuit, a display circuit, and a DC output circuit; the DC input circuit is connected to the charging and discharging circuit, the charging and discharging circuit is connected to the backup battery and the independent power supply circuit respectively, the independent power supply circuit is connected to the independent power control circuit and the DC output circuit respectively, and the independent power control circuit is connected to the display circuit;

[0061] The DC input circuit serves as the input port for an external DC power supply. During normal operation, external DC power enters the system through this port, providing the main power supply for the entire system. The charging and discharging circuit receives electrical energy from the DC input circuit, manages the charging of the backup battery, and controls the discharge of the backup battery when the main power supply is interrupted. The backup battery has a built-in rechargeable battery pack, which serves as an emergency power source. During normal power supply, it is powered by the charging and discharging circuit. When the external DC input is interrupted, it automatically switches to the discharging state to supply power to the system. In this invention, the rechargeable battery pack uses lithium batteries or nickel-metal hydride batteries; this invention does not impose specific limitations, and the specific configuration can be set according to needs. The independent power supply circuit is the core power processing circuit of the system. The unit receives power from the DC input circuit or backup battery, and is responsible for voltage regulation and filtering to ensure a stable and reliable DC output. The independent power control circuit monitors the power supply status and sets the output voltage and current parameters, manages the power supply output mode, and controls the power supply output to turn on and off. The display circuit displays power supply status information, including the current power source (main power / battery), input and output voltage / current, and fault alarm lights. It is driven by the independent power control circuit and provides a human-machine interface. The DC output circuit serves as the final output port, providing stable DC power to external experimental circuits. Regardless of whether the main power supply or backup battery is used, the power is output to the final output port through the power circuit.

[0062] Specifically, in this embodiment, the independent power supply circuit includes a power charging circuit, which is used to realize priority power supply switching between the main power supply and the backup battery, ensuring that the main power supply provides power when it is normal and automatically switches to battery power supply when the power is off; the power charging circuit includes an external input DC power supply, a DC voltage regulator module, a current limiting resistor, a battery BT1, an electrical isolation circuit, and an adjustable power supply.

[0063] Specifically, in this embodiment, the external input DC power supply uses a nominal voltage of 24V as the main power input terminal, connected to the subsequent circuit via a Schottky diode. The Schottky diode is used in the main power input circuit to prevent current from flowing back into the input terminal from the internal circuit. The DC voltage regulator module uses a 15V / 1A module to stably output the input voltage at 15V / 1A. The current-limiting resistor is connected between the output terminal of the DC voltage regulator module and the battery BT1 to limit the battery charging current and protect the backup battery. The battery has a built-in backup battery, which is a rechargeable battery that provides emergency power, using a lithium battery or a nickel-metal hydride battery. The electrical isolation circuit mainly consists of a Schottky diode connected in series between the battery and the output terminal to prevent the battery from supplying reverse power to the external load when the main power is present, achieving electrical isolation between the battery and the main power supply. When the main power is off, the battery is allowed to supply power to the load through the Schottky diode. The adjustable power supply represents the output load, i.e., the back-end circuit that needs to receive electrical energy or the equipment that needs to be powered.

[0064] Specifically, in this embodiment, the external input DC power supply is connected to the anode of diode D6, the cathode of diode D6 is connected to the DC voltage regulator module, the cathode of diode D9 and the adjustable power supply respectively, the DC voltage regulator module is connected to resistor R5, the other end of resistor R5 is connected to the positive terminal of battery BT1 and the anode of diode D8 respectively, the negative terminal of battery BT1 is grounded, and the cathode of diode D8 is connected to the anode of diode D9.

[0065] Specifically, in this embodiment, the DC voltage regulator module includes an automatically switching boost circuit and a buck circuit, as well as a first control circuit. The first control circuit is configured to detect the input voltage and compare it with the battery voltage. When the input voltage is lower than the battery voltage, the boost circuit is turned on and the buck circuit is turned off. When the input voltage is higher than the battery voltage, the boost circuit is turned off and the buck circuit is turned on. The boost circuit is used to boost the input voltage when it is lower than the battery voltage and stabilize the output. The buck circuit is used to step down the input voltage when it is higher than the battery voltage and stabilize the output. The boost circuit and buck circuit can automatically switch charging, realizing the charging and discharging management function of the backup battery. The circuit structure is simplified and the working performance is reliable. At the same time, the boost circuit and buck circuit are designed to adapt to long-term charging application scenarios and integrate battery overcharge protection and anti-passivation protection mechanisms, which can effectively avoid battery safety risks during charging and ensure battery life and charging and discharging stability.

[0066] Specifically, in this embodiment, the boost circuit includes a boost chip U1, a diode D1, a capacitor C3, a diode D2, a resistor R2, a resistor R3, an inductor L1, and a capacitor C4. Pin 1 of the boost chip U1 is connected to the anode of the diode D2 and the inductor L1. The cathode of the diode D2 is connected to the resistor R2, the capacitor C3, and the anode of the diode D1. The cathode of the diode D1 is connected to the output terminal. The other end of the resistor R2 is connected to the resistor R3 and pin 3 of the boost chip U1. The other end of the inductor L1 is connected to pin 5 of the boost chip U1, the capacitor C4, and the input terminal. The other end of pin 3 of the boost chip U1, the capacitor C3, the resistor R3, and the capacitor C4 is grounded.

[0067] Specifically, in this embodiment, the step-down circuit includes a step-down chip U2, a diode D3, a capacitor C1, a resistor R1, a resistor R4, an inductor L2, a capacitor C2, and a capacitor C5. Pin 1 of the step-down chip U2 is connected to capacitor C2. The other end of capacitor C2 is connected to inductor L2 and pin 6 of the step-down chip U2. The other end of inductor L2 is connected to resistor R1, capacitor C1, and the anode of diode D3. The cathode of diode D3 is connected to the output terminal. The other end of resistor R1 is connected to resistor R4 and pin 3 of the step-down chip U2. Pin 5 of the step-down chip U2 is connected to the input terminal and capacitor C5. Pin 2 of the step-down chip U2, capacitor C1, resistor R4, and the other end of capacitor C5 are grounded.

[0068] Specifically, in this embodiment, the control circuit is connected by multiple output circuits to enable flexible switching and control of multiple power modules to multiple output interfaces. Each output channel can be independently selected for power supply or disconnected. The control circuit mainly includes an input terminal, an output terminal, and a switch matrix. In this invention, the output terminal has 4-8 output interfaces, each corresponding to an independent load or experimental circuit channel. The input terminal has 2 input interfaces. This invention does not impose specific limitations and can be set according to needs. The switch matrix consists of multiple bidirectional switching circuits forming an m*n switching network, where m is the number of output interfaces and n is the number of power modules. Each output channel contains two switches to enable or disable the switching circuit.

[0069] See Figures 9-10 According to another aspect of the present invention, the present invention provides a device test power supply, the device test power supply including the aforementioned device test circuit; the device test power supply can quickly set and adjust voltage and current, has constant voltage and constant current dual-mode output, adopts a compact structural design, with an overall size not exceeding 10cm*10cm*10cm cube structure, and the control circuit and output circuit adopt a matrix output structure and flexible connection system to realize rapid independent combination of multiple outputs; by combining the outputs of independent power modules, the output parameters of the independent power modules can be expanded, including but not limited to adjusting parameters such as voltage level, output current level, output polarity, and number of output interfaces.

[0070] See Figure 11 According to another aspect of the present invention, a device testing method is provided, comprising the following steps:

[0071] S1. Connect the device under test to the experimental circuit, and set the output combination mode of the power module through the switch matrix of the control circuit;

[0072] S2. Set the output voltage, current parameters, and operating mode via the independent power supply front panel;

[0073] S3. Start the power supply to power the experimental circuit and monitor the output parameters in real time;

[0074] S4. After the test is completed, the energy storage element in the experimental circuit is discharged by switching the connection through the control circuit.

[0075] Specifically, in this embodiment, the device testing method uses the aforementioned device test power supply to test the components. According to the test requirements, the system output is completed by turning the modular matrix architecture in the configuration control circuit on and off. By combining power modules, the corresponding power module is directly selected and set during single-channel testing; during multi-channel series / parallel testing, each module is connected to the control circuit and electrically connected through wiring harnesses. After combination, the setting is completed through DIP switches; when the experimental circuit is an energy storage type test circuit, the connection and disconnection of the load can be realized through the series / parallel combination of the output terminals of the control circuit matrix architecture.

[0076] Specifically, in this embodiment, the device testing method is applicable to device testing using this compact combinable test power supply. It can cover various discrete semiconductors such as diodes, transistors, MOSFETs, and IGBTs, as well as passive devices such as resistors, capacitors, and inductors, and some integrated circuits for single-parameter testing and multi-parameter collaborative testing scenarios. It is suitable for different application scenarios such as high-precision verification testing in the laboratory, rapid batch testing on the production line, and reliability testing under high-temperature environments.

[0077] Specifically, in this embodiment, the device under test is connected to the experimental circuit. The output interface is connected to the experimental circuit according to the test type (e.g., forward excitation, reverse bias, long-term power-on operation, etc.), and the correct polarity is set. For environmental tolerance testing scenarios, the assembled experimental circuit is placed in an environmental test chamber, and the experimental circuit in the test chamber is connected to an external power supply via test cables. The display mode and content of the display screen are selected using the function buttons and knobs on the front panel of the power module, choosing between constant voltage mode and constant current mode. For example, constant voltage mode can be selected when conducting device withstand voltage testing, and constant current mode can be selected when conducting leakage current testing. Output voltage, current, and other parameters are set using the knobs (rotary encoder) on the panel. For single-channel testing, the target value is directly input. For multi-channel combined testing, the single-channel parameters are set according to the combination logic (e.g., voltage is proportionally distributed according to the total voltage when connected in series, and current is proportionally set according to the total current when connected in parallel).

[0078] Single-channel test procedure: Press the independent power switch, the power supply will start automatically, read the preset parameters, and supply power to the experimental circuit according to the preset voltage and current parameters; at the same time, it will detect the connection status of the output interface and display the output parameters on the display screen in real time. The display content on the front panel can be set through the function buttons and selection knobs on the front panel, such as setting the display screen to display parameters such as output voltage, current and system temperature in real time; by comparing the real-time output parameters with the expected state, the operating status of the experimental circuit can be well monitored; after the test time is reached, the power supply will be turned off and the experiment will end.

[0079] Multi-channel combination testing: By setting the connection method of the control circuit, multiple independent power supplies can be combined in series, parallel, or mixed to meet the needs of complex power supply configurations. If a test combination needs to be changed, the module does not need to be disassembled. By setting the functional parameters of the power module and the on / off settings of the control circuit switches, settings such as polarity reversal, voltage ratio increase / decrease, and current ratio increase / decrease can be quickly completed without changing the existing wiring of the experimental circuit. The system output parameters are displayed in real time on the power module's display screen. Multiple channels can run independently during the experiment. Through the control circuit settings, a certain output channel can be switched and analyzed without affecting the normal testing of other output channels.

[0080] Environmental testing: The experimental circuit is placed in an environmental test chamber, and the output terminal of the test power supply is electrically connected to the experimental circuit through a wiring harness. Based on the backup battery inside the power module, a stable power supply can be provided to the experimental circuit for a long time without interruption. For loads or test equipment that are inconvenient to put into the test chamber, the experimental circuit can be quickly connected to the load or test equipment by relying on the multiple output ports of the control circuit and setting the on and off of the switches in the control circuit.

[0081] Specifically, in this embodiment, the present invention solves the problems of existing test power supplies being bulky, lacking cascading flexibility, and struggling to balance testing accuracy and portability. This test power supply adopts a compact cubic structure design, with an overall size not exceeding 10cm*10cm*10cm. It features constant current and constant voltage dual-mode output functions, interactive control for independent output adjustment, and innovatively employs a modular matrix architecture and flexible connection system to achieve rapid independent combination of multiple outputs. Each output current ranges from 0-3A with an accuracy of 1%. It is suitable for testing the electrical parameters of various devices such as diodes, transistors, and MOSFETs, and is particularly suitable for high-precision laboratory testing and rapid production testing scenarios, featuring small size, flexible combination, and precise control.

[0082] Specifically, in this embodiment, external AC power is rectified by the AC / DC module to form stable DC power, which is then supplied to the input DC bus. This bus serves as a common power supply channel, providing input power to multiple parallel-connected power modules. Each independent power module has constant voltage / constant current dual-mode output capability and is equipped with an independent control circuit to achieve precise adjustment and real-time monitoring of parameters such as voltage and current. Each control circuit connects its corresponding power output to a common output bus through flexible connection, and finally connects to the experimental circuit. This architecture supports independent combination and dynamic switching of multiple outputs, and allows for the start / stop and parameter setting of any channel through interactive operation.

[0083] Specifically, in this embodiment, taking single-channel test power supply testing as an example, the AC / DC module uses a 220VAC to 24VDC converter to convert 220V AC power into 24V DC power to supply the power module. The power charging circuit under the power module divides the 24V DC input into two parts: one part supplies the adjustable power supply, which converts it into the corresponding experimental voltage to power the subsequent circuits; the other part supplies the 15V / 1A module, i.e., the DC voltage regulator module, which, after conversion by the 15V / 1A module, supplies power to the backup battery through a current-limiting resistor. In this embodiment, the backup battery is a 14.7V NiMH battery pack. This circuit can be externally connected. When an abnormality occurs, the system automatically switches to the backup battery pack to ensure uninterrupted power supply. Simultaneously, the 15V / 1A module ensures that the backup battery will not overcharge due to prolonged disuse, meeting the requirements for long-term reliable operation of the power circuit. In this embodiment, the 15V / 1A module consists of three parts: a boost converter, a buck converter, and a control unit. The boost converter uses an SX1308 boost chip, with a minimum input voltage as low as 2V. The output current is adjusted by regulating the ratio of resistors R2 and R3. The start-up and shutdown of the boost converter are controlled by the first control circuit. When the EN pin is high, the boost converter... The boost circuit is turned on and outputs a set voltage. When the EN pin is low, the boost circuit is turned off. The buck circuit uses an LM50410 buck chip with a maximum input voltage of 40V. The output current is adjusted by changing the ratio of resistors R1 and R4. The start-up and shutdown of the buck circuit are controlled by the first control circuit. When the EN pin is high, the buck circuit is turned on; when the EN pin is low, the buck circuit is turned off. The start-up and shutdown of both the boost and buck circuits are controlled by the first control circuit. In the first control circuit, Vcc is the battery voltage, and V1 is the input voltage. PR4 is connected to the EN pin of the boost circuit, and PR5 is connected to... The input voltage is connected to the EN pin of the buck converter circuit. Resistors R1 and R4 sample the input voltage, and this sampled voltage is compared with the battery pack voltage samples from resistors R2, R3, R10, and R11 to control the outputs of PR4 and PR5. When the input voltage is lower than the battery pack voltage, PR4 outputs a high level, the boost converter is on, PR5 remains low, and the buck converter is off, with the boost converter powering the subsequent circuits. When the input voltage is higher than the battery pack voltage, PR4 output changes from high to low, the boost converter is off, PR5 changes from low to high, and the buck converter is on, powering the subsequent circuits. This achieves wide-range input voltage adaptation.

[0084] For single-channel test power supply applications, the output of the power module is connected to the V1 and G1 ports of the switch matrix. By controlling the closing of DIP switches S1 and S6 through DIP switches, the experimental circuit is powered.

[0085] The power module is an independent power system with backup battery power capability. It can automatically switch to internal battery power when the main power supply is interrupted, thereby ensuring the continuous and stable operation of the experimental circuit. The independent power system consists of the following core modules, see [link to relevant documentation]. Figure 3 The system comprises several components: a DC input circuit, which serves as the input port for external DC power; a charging / discharging circuit, which receives power from the DC input circuit and manages the charging of the backup battery; and a backup battery that discharges into the system during power outages. The backup battery, consisting of a built-in rechargeable battery pack (such as lithium or nickel-metal hydride batteries), acts as an emergency power source. During normal power supply, it is charged by the charging / discharging circuit; and when the external DC input is interrupted, it automatically switches to discharge mode to supply power to the system. The independent power supply circuit, the core power processing unit of the system, receives power from the DC input circuit or the backup battery. The power supply is responsible for voltage regulation and filtering to ensure a stable and reliable DC output. An independent power control circuit monitors the power supply status, sets output voltage and current parameters, manages the power supply output mode, and controls the power output's on / off state. A display circuit displays real-time power status information, such as the current power source (main power / battery), input / output voltage / current, and fault alarms. Driven by the independent power control circuit, it provides a human-machine interface. The DC output circuit is the final output port of the independent power supply, providing stable DC power to external experimental circuits. Whether using main power or a backup battery, the output is sent to this port through the independent power circuit.

[0086] The main function of the power charging circuit in the independent power supply is to achieve priority power switching between the main power supply and the backup battery, ensuring that it supplies power when the main power supply is normal and automatically switches to battery power when power is lost. The circuit connection is as follows: 24V / IN: This is the external input DC power supply with a nominal voltage of 24V, serving as the main power input terminal. It is connected to the subsequent circuit through Schottky diode D6; Schottky diode D6 is used for the main power input circuit to prevent current from flowing back into the input terminal from the internal circuit; 15V / 1A module: This is a DC voltage regulator module that stabilizes the input voltage to 15V / 1A. Its input terminal is connected to the node after Schottky diode D6, and its output terminal is connected to the adjustable power supply and subsequent diodes D8 and D9; The 15 / 1A module circuit contains two sets of power supply circuits and one first control circuit; The two sets of power supply circuits are a boost circuit and a buck circuit respectively; The boost circuit can boost the input voltage lower than the battery voltage and stabilize the output; The buck circuit can buck the input voltage higher than the battery voltage and stabilize the output; The first control circuit can automatically detect the input voltage and connect to the battery. The voltage is compared. When the input voltage is lower than the battery voltage, the boost circuit is activated and the buck circuit is deactivated, with the boost circuit outputting a stable voltage. When the input voltage is higher than the battery voltage, the control circuit deactivates the boost circuit and activates the buck circuit, with the buck circuit outputting a stable voltage. Resistor R5 (100-1000 ohms) is connected between the output of the 15V voltage regulator module and battery BT1. Its main function is to limit the battery charging current and protect the backup battery. The built-in backup battery provides emergency power for rechargeable batteries (such as lithium batteries or nickel-metal hydride batteries). Diodes D8 and D9 are both Schottky diodes, connected in series between the battery and the output to prevent the battery from supplying reverse power to the external load when the main power is available, thus achieving electrical isolation between the battery and the main power supply. When the main power is off, the battery is allowed to supply power to the load through diodes D8 and D9. The adjustable power supply represents the output load, i.e., the back-end circuit that needs to receive electrical energy or the equipment that needs to be powered.

[0087] The control circuit is a multi-source power selection and distribution system that uses a switch matrix to achieve controllable connection between the input power supply and the output interface; see also Figure 2This system is used to flexibly switch and control multiple independent power supplies (V1, V2) to multiple output interfaces (from the first output terminal to the eighth output terminal). Each output channel can be independently selected to be powered by V1 or V2, or disconnected. For the input terminals, V1 represents the input terminal of power supply 1, and G1 is the ground reference point connected to V1, forming a complete loop. V2 represents the input terminal of power supply 2, and G2 is the ground reference point connected to V2. V1 / G1 and V2 / G2 are two independent DC power supply input channels. For the output terminals, the first output terminal, second output terminal, ..., the eighth output terminal are eight output interfaces, each corresponding to an independent load or experimental circuit channel. The switching matrix diagram consists of a large number of switching circuits forming an 8*2 switching network. See [link to diagram]. Figure 8 The bidirectional switching circuit includes two switches for each output channel (e.g., the first output terminal): one connected to the V1 / G1 path and the other to the V2 / G2 path. Connecting to V1 or V2 can be selected by opening and closing the switch circuit. Each switch is numbered, for example: S1, S2, S3, ... S40. Each output channel uses four switches; for example, the "first output terminal" uses S1 (connected to V1) and S3 (connected to V2), the "second output terminal" uses S2 (connected to G1) and S4 (connected to G2), and so on, with four switches corresponding to one output channel. The power input sides V1 and V2 are connected to two independent power supplies of the system; G1 and G2 are the ground terminals of their respective power supplies. The power source for each output interface is determined by controlling the on / off state of each switch circuit (S1~S40). For example, if you want the "first output terminal" to be powered by V1, close S1; if you want the "first output terminal" to be powered by V2, close S3; if you do not use the "first output terminal", open S1~S4. All output channels are independent of each other and do not affect each other. Different output interfaces can be powered by different power supplies to meet the needs of complex experiments.

[0088] Specifically, in this embodiment, the device test power supply has a small cubic box structure. The outer shell is made of white or gray metal or plastic, with a smooth surface, compact size, and low space requirements, and can be placed in space-constrained locations such as experimental benches or equipment racks. There are four small feet at the bottom for stable support of the device. The display screen is located in the upper center of the panel, and the displayed content may include: "OUT": output voltage, "0.000A": output current, "ON 00.00" channel status and timing information, with clear font for easy reading. The black circular knob on the right side of the display screen is used to adjust the output voltage or current parameters. It can be finely adjusted by rotating and switched by pressing. The power switch, located at the lower right of the display screen, is a green circular button labeled "ON," used to turn the device on or off. The output interfaces (terminal blocks) consist of two circular connectors: a red terminal for positive output (+) and a black terminal for negative output (-). The input interfaces have white / silver terminals. A USB interface, located to the right of the output terminals, is a standard USB-A interface for computer connection and data recording. A small black dot on the left side of the display screen is the function control button, used for setting functions and switching modes. The device has a three-dimensional, cube-shaped design with rounded corners and a slightly concave panel forming a protective frame to prevent accidental activation. The interfaces and buttons are conveniently located on the front panel. The top of the device is flat, allowing for stacking or installation of other modules.

[0089] Specifically, in this embodiment, two independent power supplies are used: a first independent power supply and a second independent power supply. The positive output of the first independent power supply is connected to V1 of the switch matrix, and the negative output is connected to G1. The positive output of the second independent power supply is connected to V2 of the switch matrix, and the negative output is connected to G2. The positive terminal of the LED under test is connected to the first output terminal, and the negative terminal is connected to the second output terminal. The collector of the phototransistor under test is connected to the third output terminal, and the emitter is connected to the fourth output terminal. The DIP switches S1, S6, S11, and S16 of the switch matrix are closed, and the tested optocoupler is placed in a high-temperature environmental test chamber. The first independent power supply has an output current of 2mA, and the second independent power supply has an output voltage of 5V. Both independent power supplies are turned on. After the test environment stabilizes and meets the test requirements, the output currents Iout1 and Iout2 of the first and second independent power supplies are read and recorded from their displays. The high-temperature CTR parameter of the tested optocoupler is obtained using CTR = Iout2 / Iout1. In this example, the current display accuracy of the independent power supply is 3%. If the display accuracy does not meet the test requirements, a high-precision ammeter can be used to complete the test. The specific implementation method is as follows:

[0090] Two independent power supplies are used: a first independent power supply and a second independent power supply. The positive output of the first independent power supply is connected to V1 of the switch matrix, and the negative output is connected to G1. The positive output of the second independent power supply is connected to V2 of the switch matrix, and the negative output is connected to G2. The positive terminal of the LED under test is connected to the first output terminal, and the negative terminal is connected to the fifth output terminal. The collector of the phototransistor under test is connected to the second output terminal, and the emitter is connected to the sixth output terminal. The positive terminal of the current setting of the first multimeter is connected to the seventh output terminal, and the negative terminal is connected to the third output terminal. The positive terminal of the current setting of the second multimeter is connected to the eighth output terminal, and the negative terminal is connected to the fourth output terminal. The DIP switches S1, S21, S29, S10, S7, S27, S35, and S16 of the switch matrix are closed. The optocoupler under test is placed in a high-temperature environmental test chamber, and the first independent power supply is set... The output current of the first independent power supply is 2mA, and the output voltage of the second independent power supply is set to 5V. The first and second independent power supplies are turned on. After the test environment conditions stabilize and meet the test requirements, the output voltage of the first independent power supply is adjusted by the knob on the front panel of the first independent power supply so that the reading of the first multimeter current range reaches the test value Iout1, such as 2mA. The current readings Iout1 and Iout2 of the first and second multimeters are read and recorded. The high-temperature CTR parameter of the tested optocoupler is obtained by CTR=Iout2 / Iout1.

[0091] Specifically, in this embodiment, a single-channel test power supply connection is adopted. The positive output of the power module is connected to V1 of the switch matrix, and the negative output is connected to G1. In the capacitor test circuit, the positive input is connected to the first output terminal, and the negative input is connected to the second output terminal. The load circuit is connected to the third and fourth output terminals. The voltage and current parameters of the capacitor test are set through the front panel of the independent power supply, such as 5V voltage and 50mA current. The "output control" switches S1 and S6 are closed to conduct the test. After the test, S1 and S6 are opened, and then the DIP switches S3, S8, S11, and S16 are closed. The load circuit discharges the charge in the capacitor test circuit to complete the test.

[0092] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A device testing circuit, characterized in that, include: Input circuit, power supply circuit, control circuit, and output circuit; The input circuit adopts an input DC bus circuit for receiving and distributing DC power; The power supply circuit includes multiple independent power modules, each of which obtains power from the input DC bus circuit; The control circuit achieves controllable connection between multiple output interfaces of the power supply circuit and the output circuit through a switch matrix; The output circuit is used to connect to the experimental circuit; The input DC bus circuit is a bidirectional bus, used for bidirectional transmission of DC power between the power supply circuit and the experimental circuit.

2. The device testing circuit according to claim 1, characterized in that, Each independent power module in the power supply circuit includes: DC input circuit, charging and discharging circuit, backup battery, independent power supply circuit, independent power supply control circuit, display circuit and DC output circuit; The DC input circuit is connected to the charging and discharging circuit, the charging and discharging circuit is connected to the backup battery and the independent power supply circuit respectively, the independent power supply circuit is connected to the independent power supply control circuit and the DC output circuit respectively, and the independent power supply control circuit is connected to the display circuit. The DC input circuit serves as the input port for an external DC power supply. The charging and discharging circuit is used to manage the charging of the backup battery and to control the discharge of the backup battery when the main power is interrupted. The independent power supply circuit is used to output DC power; The independent power control circuit is used to monitor and set power parameters; The display circuit is used to display power status information; The DC output circuit serves as the final output port.

3. The device testing circuit according to claim 2, characterized in that, The independent power supply circuit includes a power charging circuit, which includes an external input DC power supply, a DC voltage regulator module, a current limiting resistor, a battery BT1, an electrical isolation circuit, and an adjustable power supply.

4. A device testing circuit according to claim 3, characterized in that, The external input DC power supply is connected to the anode of diode D6. The cathode of diode D6 is connected to the DC voltage regulator module, the cathode of diode D9, and the adjustable power supply. The DC voltage regulator module is connected to resistor R5. The other end of resistor R5 is connected to the positive terminal of battery BT1 and the anode of diode D8. The negative terminal of battery BT1 is grounded. The cathode of diode D8 is connected to the anode of diode D9.

5. A device testing circuit according to claim 3, characterized in that, The DC voltage regulator module includes a boost circuit and a buck circuit that can be automatically switched, as well as a set of first control circuits; The first control circuit is configured to detect the input voltage and compare it with the battery voltage. When the input voltage is lower than the battery voltage, the boost circuit is turned on and the buck circuit is turned off; when the input voltage is higher than the battery voltage, the boost circuit is turned off and the buck circuit is turned on. The boost circuit is used to boost the input voltage that is lower than the battery voltage and stabilize the output; the buck circuit is used to buck the input voltage that is higher than the battery voltage and stabilize the output.

6. A device testing circuit according to claim 5, characterized in that, The boost circuit includes a boost chip U1, a diode D1, a capacitor C3, a diode D2, a resistor R2, a resistor R3, an inductor L1, and a capacitor C4. Pin 1 of the boost chip U1 is connected to the anode of diode D2 and inductor L1. The cathode of diode D2 is connected to resistor R2, capacitor C3, and the anode of diode D1. The cathode of diode D1 is connected to the output terminal. The other end of resistor R2 is connected to resistor R3 and pin 3 of boost chip U1. The other end of inductor L1 is connected to pin 5 of boost chip U1, capacitor C4, and the input terminal. The other end of pin 3 of boost chip U1, capacitor C3, resistor R3, and capacitor C4 is grounded.

7. A device testing circuit according to claim 5, characterized in that, The step-down circuit includes a step-down chip U2, a diode D3, a capacitor C1, a resistor R1, a resistor R4, an inductor L2, a capacitor C2, and a capacitor C5. Pin 1 of the step-down chip U2 is connected to capacitor C2. The other end of capacitor C2 is connected to inductor L2 and pin 6 of the step-down chip U2. The other end of inductor L2 is connected to resistor R1, capacitor C1, and the anode of diode D3. The cathode of diode D3 is connected to the output terminal. The other end of resistor R1 is connected to resistor R4 and pin 3 of the step-down chip U2. Pin 5 of the step-down chip U2 is connected to the input terminal and capacitor C5. Pin 2 of the step-down chip U2, capacitor C1, resistor R4, and the other end of capacitor C5 are grounded.

8. A device testing circuit according to any one of claims 1-7, characterized in that, The switching matrix consists of an m*n switching network composed of multiple bidirectional switching circuits, where m is the number of output interfaces and n is the number of power modules.

9. A device test power supply, characterized in that, The device test power supply includes a device test circuit as described in any one of claims 1-8.

10. A device testing method comprising the device test power supply as described in claim 9, characterized in that, Includes the following steps: S1. Connect the device under test to the experimental circuit, and set the output combination mode of the power module through the switch matrix of the control circuit; S2. Set the output voltage, current parameters, and operating mode via the independent power supply front panel; S3. Start the power supply to power the experimental circuit and monitor the output parameters in real time; S4. After the test is completed, the energy storage element in the experimental circuit is discharged by switching the connection through the control circuit.

Images