A switching circuit and test apparatus

Abstract

The application provides a switching circuit and test equipment, and belongs to the technical field of power electronics. The circuit comprises at least one switching module and a gating module. The switching module comprises a first switching submodule and a second switching submodule. The first end of the first switching submodule is connected with a group of data transmission ends of a first measured module, and the second end is connected with a group of data transmission ends of a second measured module. The first end of the second switching submodule is connected with another group of data transmission ends of the first measured module, and the second end is connected with another group of data transmission ends of the second measured module. The fifth end of the gating module is used for receiving an external control signal. The gating module is used for controlling the first switching submodule and the second switching submodule to be connected with the first measured module at the same time or controlling the first switching submodule and the second switching submodule to be connected with the second measured module at the same time according to the received external control signal. The circuit can provide data transmission channels for multiple measured modules and overcome the size limitation of an opening.

Description

Technical Field

[0001] This article relates to power electronics technology, particularly a switching circuit and testing equipment. Background Technology

[0002] To verify equipment performance, high and low temperature tests or vibration tests are usually performed. If only one module is tested at a time, the module must be switched or rotated after each test or each direction is completed, which greatly increases the test preparation time.

[0003] To improve equipment testing efficiency and save testing time, multiple modules under test (DUTs) are typically placed simultaneously in high and low temperature chambers or vibration tables for environmental testing. However, during high and low temperature or vibration testing, each DUT has multiple port test leads that need to be led out of the high and low temperature test chamber. Since the size of the lead-out holes is fixed and they need to be sealed with flexible materials, the number of transmission lines that can be led out is limited, which in turn limits the number of devices that can be tested simultaneously, thus failing to meet the user's testing needs. Summary of the Invention

[0004] This application provides a switching circuit and a testing device that enables multiple modules under test to share a single transmission line, overcoming existing technical limitations and improving testing efficiency. In a first aspect, this application provides a switching circuit connected to a module under test, the module under test including at least a first module under test and a second module under test; each module under test includes at least two sets of data transmission terminals; the switching circuit includes: At least one switching module and a gating module; The switching module includes a first switching submodule and a second switching submodule; The first end of the first switching submodule is connected to a set of data transmission terminals of the first module under test, and the second end is connected to a set of data transmission terminals of the second module under test. The first end of the second switching submodule is connected to another set of data transmission ends of the first module under test, and the second end is connected to another set of data transmission ends of the second module under test. The fifth terminal of the gating module is used to receive external control signals. The gating module is used to control the first switching submodule and the second switching submodule to be connected to the first module under test simultaneously, or to control the first switching submodule and the second switching submodule to be connected to the second module under test simultaneously, according to the received external control signals.

[0005] In one possible implementation, the third, fourth, and fifth terminals of the first switching submodule are connected to the first, second, and third terminals of the gating module, respectively; the third, fourth, and fifth terminals of the second switching submodule are connected to the first, second, and fourth terminals of the gating module, respectively. Each of the switching submodules includes a switching unit, and the switching unit includes a first switching unit and a second switching unit; The first end of the first switching unit is the first end of the corresponding switching submodule, the second end is the fifth end of the corresponding switching submodule, and the control end is the third end of the corresponding switching submodule. The first switching unit is used to connect or disconnect the first and fifth ends of the corresponding switching submodule according to the signal from the control end of the first switching unit. The first end of the second switching unit is the second end of the corresponding switching submodule, the second end is the fifth end of the corresponding switching submodule, and the control end is the fourth end of the corresponding switching submodule. The second switching unit is used to connect or disconnect the second and fifth ends of the corresponding switching submodule according to the signal from the control end of the first switching unit.

[0006] In one possible implementation, any switching unit includes a switching circuit and a filtering circuit; The first terminal of the switching circuit is the first terminal of the corresponding switching unit, the second terminal is the second terminal of the corresponding switching unit, and the control terminal is connected to the output terminal of the filter circuit. The input terminal of the filter circuit is the control terminal of the corresponding switching unit; The filtering circuit is used to filter the signal at the input terminal of the filtering circuit and output it to the control terminal of the switching circuit; the switching circuit is used to connect or close the first and second terminals of the corresponding switching unit according to the signal at the control terminal of the switching circuit.

[0007] In one possible implementation, each set of data transmission ends of any module under test is used to transmit differential data, including a forward data transmission end and a reverse data transmission end. The switching circuit includes a first switching sub-circuit and a second switching sub-circuit. The first terminals of the first and second switching sub-circuits form the first terminal of the corresponding switching unit. The first terminals of the first and second switching sub-circuits are respectively connected to the forward data transmission terminal and the reverse data transmission terminal in the same group of data transmission terminals of the module under test. The second terminals of the first and second switching sub-circuits form the second terminal of the corresponding switching unit. The control terminal of the first and second switching sub-circuits is connected to the control terminal of the corresponding switching unit. Each of the switching sub-circuits includes an NMOS device, a first bias circuit, and a second bias circuit; The first source of the NMOS device is the first terminal of the corresponding switching sub-circuit, which is connected to the first terminal of the first bias circuit and the positive data transmission terminal or the reverse data transmission terminal in a set of data transmission terminals of the module under test. The second source is the second terminal of the corresponding switching sub-circuit, which is connected to the first terminal of the second bias circuit. The gate is the control terminal of the corresponding switching sub-circuit. The second terminal of the first bias circuit and the second terminal of the second bias circuit are both grounded.

[0008] In one possible implementation, the gating module includes a transmission circuit, a transmission line, and a control unit; The control unit is used to transmit the received external control signals to the output terminal of the transmission circuit via a transmission line; The output terminals of the transmission circuit include a first output terminal and a second output terminal, which are respectively the first and second terminals of the gating module; the transmission circuit is used to control the output of a control signal from the first or second output terminal of the transmission circuit according to the signal from the control terminal of the transmission circuit.

[0009] In one possible implementation, the transmission circuit includes a first voltage pull-down circuit, a second voltage pull-down circuit, a first current limiting circuit, a second current limiting circuit, a first surge suppression circuit, a second surge suppression circuit, a filter protection circuit, and a connector. The first terminal of the first voltage pull-down circuit is the first output terminal of the transmission circuit, and the second terminal is grounded. The first terminal of the first current limiting circuit is connected to the first terminal of the first voltage pull-down circuit, and the second terminal is connected to the first terminal of the first surge suppression circuit and the second terminal of the connector, respectively. The second terminal of the first surge suppression circuit is grounded; The first terminal of the second voltage pull-down circuit is the second output terminal of the transmission circuit, and the second terminal is grounded. The first terminal of the second current limiting circuit is connected to the first terminal of the second voltage pull-down circuit, and the second terminal is connected to the first terminal of the second surge suppression circuit and the third terminal of the connector, respectively. The second terminal of the second surge suppression circuit is grounded; The first terminal of the filter protection circuit is connected to the power supply, and the second terminal is connected to the first terminal of the connector. Connectors are used to connect transmission lines.

[0010] One possible implementation also includes a power supply module; The power module includes a dual-channel DC-DC power chip with enable function, a third voltage pull-down circuit, and a fourth voltage pull-down circuit.

[0011] The first enable terminal of the power chip is connected to the first terminal of the third voltage pull-down circuit and the first terminal of the gating module, respectively. The second enable terminal is connected to the first terminal of the fourth voltage pull-down circuit and the second terminal of the gating module, respectively. The first voltage output terminal is connected to the power supply terminal of the first module under test, and the second voltage output terminal is connected to the power supply terminal of the second module under test. The first enable terminal is used to control the output state of the first voltage output terminal, and the second enable terminal is used to control the output state of the second voltage output terminal. The second terminal of the third voltage pull-down circuit and the second terminal of the fourth voltage pull-down circuit are grounded.

[0012] In one possible implementation, any switching submodule includes a 1394 bus interface, wherein the first end of the switching submodule is the first differential data terminal of the 1394 bus interface, and the second end is the second differential data terminal of the 1394 bus interface.

[0013] Secondly, embodiments of this application also provide a testing device, including any of the switching circuits provided in the first aspect.

[0014] One possible implementation also includes a signal analysis device; The signal analysis equipment is connected to the output of the switching circuit and is used to analyze the test data output by the switching circuit.

[0015] The switching circuit and testing equipment provided in this application include a switching circuit and a module under test (DUT) connected together. The DUT includes at least a first DUT and a second DUT. Each DUT includes at least two sets of data transmission terminals. The switching circuit includes at least one switching module and a gating module. The switching module includes a first switching submodule and a second switching submodule. A first terminal of the first switching submodule is connected to one set of data transmission terminals of the first DUT, and a second terminal is connected to one set of data transmission terminals of the second DUT. A first terminal of the second switching submodule is connected to another set of data transmission terminals of the first DUT, and a second terminal is connected to another set of data transmission terminals of the second DUT. The transmission end is connected; the fifth terminal of the gating module is used to receive external control signals. The gating module is used to control the first switching submodule and the second switching submodule to be connected to the first module under test simultaneously, or to control the first switching submodule and the second switching submodule to be connected to the second module under test simultaneously, according to the received external control signals. This circuit can be connected to multiple modules under test, providing data transmission channels for multiple modules under test, reducing the number of transmission lines, and overcoming the opening size limitations faced by testing environments such as high and low temperature chambers and vibration tables. This circuit can also switch the modules under test in response to external control signals, reducing the number of times the equipment is disassembled when testing multiple devices, and improving testing efficiency.

[0016] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application can be realized and obtained by means of the embodiments described in the description and the accompanying drawings. Attached Figure Description

[0017] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0018] Figure 1 This application provides an embodiment of a switching circuit and its structural schematic diagram. Figure 2 This is a schematic diagram of the structure of a switching submodule provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of a switching unit provided in an embodiment of this application; Figure 4 A circuit diagram of a switching unit provided in an embodiment of this application; Figure 5 This is a schematic diagram of a switching circuit provided in an embodiment of this application; Figure 6 A circuit diagram of a switching module provided in an embodiment of this application; Figure 7 This application provides an example of another switching circuit and its structural schematic diagram. Figure 8 A circuit diagram of a transmission circuit provided in an embodiment of this application; Figure 9 This is a circuit diagram of a power module provided in an embodiment of this application. Detailed Implementation

[0019] This application describes several embodiments, but these descriptions are exemplary and not restrictive, and many more embodiments and implementations are possible within the scope of the embodiments described herein, which will be apparent to those skilled in the art. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with or in lieu of any other feature or element in any other embodiment.

[0020] This application includes and contemplates combinations of features and elements known to those skilled in the art. The embodiments, features, and elements disclosed in this application can also be combined with any conventional features or elements to form unique inventive solutions. Any feature or element of any embodiment can also be combined with features or elements from other inventive solutions to form another unique inventive solution. Therefore, it should be understood that any feature shown and / or discussed in this application can be implemented individually or in any suitable combination. Therefore, the embodiments are not limited except by the limitations imposed by the appended claims and their equivalents. Furthermore, various modifications and changes can be made within the scope of the appended claims.

[0021] Furthermore, in describing representative embodiments, the specification may have presented methods and / or processes as a specific sequence of steps. However, the method or process should not be limited to a specific order of steps to the extent that it does not depend on this specific order. As will be understood by those skilled in the art, other sequences of steps are also possible. Therefore, the specific order of steps set forth in the specification should not be construed as a limitation of the claims. Moreover, the claims relating to the method and / or process should not be limited to the steps performed in the order written, and those skilled in the art will readily understand that these orders can be varied and still remain within the spirit and scope of the embodiments of this application.

[0022] To address the problems existing in the prior art, this application provides a switching circuit that can simultaneously connect at least two modules under test (DUTs). This circuit can be placed in the testing environment (such as a high / low temperature chamber or vibration table) without increasing the number of test transmission lines extending from the testing environment. An external signal controls the connection state between the switching circuit and the different DUTs to select the module currently being tested and output the test data of the selected module, thus completing the testing of the selected testing equipment.

[0023] like Figure 1 As shown, this application embodiment provides a switching circuit 100, which is connected to the module under test.

[0024] The module under test includes at least a first module under test 200 and a second module under test 300.

[0025] Each module under test includes at least two sets of data transmission terminals.

[0026] Specifically, the data transmission ports included in the module under test can be a set of receive ports and a set of transmit ports. Any set of data transmission ports can be differential data transmission ports.

[0027] Optionally, the data transmission interface of the module under test is an IEEE 1394 bus interface. The module under test can be an IEEE 1394 bus board.

[0028] like Figure 1 As shown, the switching circuit 100 includes: At least one switching module 11 and a gating module 12.

[0029] The switching module 11 includes a first switching submodule 111 and a second switching submodule 112.

[0030] The first end of the first switching submodule 111 is connected to a set of data transmission terminals of the first module under test 200, and the second end is connected to a set of data transmission terminals of the second module under test 300.

[0031] The first end of the second switching submodule 112 is connected to another set of data transmission terminals of the first module under test 200, and the second end is connected to another set of data transmission terminals of the second module under test 300.

[0032] The fifth terminal of the gating module 12 is used to receive external control signals. The gating module 12 is used to control the first switching submodule 111 and the second switching submodule 112 to be connected to the first test module 200 simultaneously, or to control the first switching submodule 111 and the second switching submodule 112 to be connected to the second test module 300 simultaneously, according to the received external control signals.

[0033] Specifically, when an external control signal simultaneously connects the first switching submodule 111 and the second switching submodule 112 to the first module under test 200, the first module under test 200 is selected and enters the test state, while the second module under test 300 is not selected and cannot enter the test state. In this case, the first module under test 200 can transmit test-related data through the first switching submodule 111, the second switching submodule 112, and the gating module 12, while the second module under test 300 cannot transmit data. Conversely, when an external control signal simultaneously connects the first switching submodule 111 and the second switching submodule 112 to the second module under test 300, the second module under test 300 is selected and enters the test state, while the first module under test 200 is not selected and cannot enter the test state. In this case, the second module under test 300 can transmit test-related data through the first switching submodule 111, the second switching submodule 112, and the gating module 12, while the first module under test 200 cannot transmit data.

[0034] The switching circuit and test equipment provided in this application embodiment include a switching circuit and a module under test (DUT) connected together. The DUT includes at least a first DUT and a second DUT. Each DUT includes at least two sets of data transmission terminals. The switching circuit comprises at least one switching module and a gating module. The switching module includes a first switching submodule and a second switching submodule. A first end of the first switching submodule is connected to one set of data transmission terminals of the first DUT, and a second end is connected to one set of data transmission terminals of the second DUT. A first end of the second switching submodule is connected to another set of data transmission terminals of the first DUT, and a second end is connected to another set of data transmission terminals of the second DUT. The group data transmission terminal is connected; the fifth terminal of the gating module is used to receive external control signals. The gating module is used to control the first switching submodule and the second switching submodule to be connected to the first module under test simultaneously, or to control the first switching submodule and the second switching submodule to be connected to the second module under test simultaneously, according to the received external control signals. This circuit can be connected to multiple modules under test, providing data transmission channels for multiple modules under test, reducing the number of transmission lines, and overcoming the opening size limitations faced by testing environments such as high and low temperature chambers and vibration tables. This circuit can also switch the modules under test in response to external control signals, reducing the number of times the equipment is disassembled during multi-device testing and improving testing efficiency.

[0035] In one possible implementation, any switching submodule includes a 1394 bus interface, wherein the first end of the switching submodule is the first differential data terminal of the 1394 bus interface, and the second end is the second differential data terminal of the 1394 bus interface.

[0036] This setting allows for the separate enabling of one transmission channel in each of the two switching submodules to transmit test data, with one channel responsible for sending data and the other for receiving data. For example, to enable only the first module under test 200 for data communication testing, the SEL1 signal is pulled high (set to a high level) by the gating module 12, thereby powering on the first module under test 200 via the power chip. Simultaneously, the first switching submodule 111 selects IN1+ / IN1- for data transmission, while IN2+ / IN2- is in a disabled state and cannot transmit data, thus performing a data transmission test on the first module under test 200; the second switching submodule 112 selects IN1+ / IN1- for data reception, while IN2+ / IN2- is in a disabled state and cannot transmit data, thus performing a data reception test on the first module under test 200.

[0037] In one possible implementation, the third, fourth, and fifth terminals of the first switching submodule are connected to the first, second, and third terminals of the gating module, respectively; and the third, fourth, and fifth terminals of the second switching submodule are connected to the first, second, and fourth terminals of the gating module, respectively.

[0038] Among them, such as Figure 2As shown, any switching submodule includes a first switching unit 21 and a second switching unit 22.

[0039] The first end of the first switching unit 21 is the first end of the corresponding switching submodule, the second end is the fifth end of the corresponding switching submodule, and the control end is the third end of the corresponding switching submodule. The first switching unit 21 is used to connect or disconnect the first end and the fifth end of the corresponding switching submodule according to the signal from the control end of the first switching unit 21.

[0040] The first end of the second switching unit 22 is the second end of the corresponding switching submodule, the second end is the fifth end of the corresponding switching submodule, and the control end is the fourth end of the corresponding switching submodule. The second switching unit 22 is used to connect or disconnect the second and fifth ends of the corresponding switching submodule according to the signal from the control end of the second switching unit 22.

[0041] Specifically, both the first switching submodule 111 and the second switching submodule 112 include the first switching unit and the second switching unit provided in this embodiment.

[0042] For the first switching submodule 111, its internal first switching unit is used to connect or disconnect the first and fifth terminals of the first switching submodule according to the signal from the control terminal of the first switching unit. Since the first terminal of the first switching submodule is connected to a set of data transmission terminals of the first tested module, and the fifth terminal is connected to the third terminal of the gating module, the first switching unit inside the first switching submodule 111 is also used to connect or disconnect the set of data transmission terminals of the first tested module and the third terminal of the gating module according to the signal from the control terminal of the first switching unit. For the first switching submodule 111, its internal second switching unit is used to connect or disconnect the second and fifth terminals of the first switching submodule according to the signal from the control terminal of the second switching unit. Since the second terminal of the first switching submodule is connected to a set of data transmission terminals of the second tested module, and the fifth terminal is connected to the third terminal of the gating module, the second switching unit inside the first switching submodule 111 is also used to connect or disconnect the set of data transmission terminals of the second tested module and the third terminal of the gating module according to the signal from the control terminal of the second switching unit.

[0043] For the second switching submodule 112, its internal first switching unit is used to connect or disconnect the first and fifth terminals of the first switching submodule according to the signal from the control terminal of the first switching unit. Since the first terminal of the second switching submodule is connected to another set of data transmission terminals of the first tested module, and the fifth terminal is connected to the fourth terminal of the gating module, the first switching unit inside the second switching submodule 112 is also used to connect or disconnect a set of data transmission terminals of the second tested module and the fourth terminal of the gating module according to the signal from the control terminal of the first switching unit. The second switching unit inside the second switching submodule 112 is used to connect or disconnect the second and fifth terminals of the first switching submodule according to the signal from the control terminal of the second switching unit. Since the second terminal of the second switching submodule is connected to another set of data transmission terminals of the second tested module, and the fifth terminal is connected to the fourth terminal of the gating module, the second switching unit inside the second switching submodule 112 is also used to connect or disconnect another set of data transmission terminals of the second tested module and the fourth terminal of the gating module according to the signal from the control terminal of the second switching unit.

[0044] This setting enables control over the passage of dual signals, improving testing efficiency while meeting testing requirements.

[0045] like Figure 3 As shown, in one possible implementation, any switching unit includes a switching circuit 31 and a filtering circuit 32.

[0046] The first terminal of the switching circuit 31 is the first terminal of the corresponding switching unit, the second terminal is the second terminal of the corresponding switching unit, and the control terminal is connected to the output terminal of the filter circuit 32.

[0047] The input terminal of the filter circuit 32 is the control terminal of the corresponding switching unit.

[0048] The filter circuit 32 is used to filter the signal at the input terminal of the filter circuit 32 and output it to the control terminal of the switch circuit 31; the switch circuit 31 is used to connect or close the first and second terminals of the corresponding switching unit according to the signal at the control terminal of the switch circuit 31.

[0049] Specifically, each switching unit includes the switching circuit and filtering circuit provided in this embodiment.

[0050] This setting can filter out interference signals, improve the stability of the internal signals of the switching circuit 31, and improve the accuracy of test results.

[0051] Figure 4 This is a circuit diagram of a switching unit provided in an embodiment of this application, such as... Figure 4 As shown, in one possible implementation, the filter circuit 32 includes a first resistor R108 and a first capacitor C112; The first terminal of the first resistor R108 and the first terminal of the first capacitor C112 are connected to form the output terminal of the filter circuit 32.

[0052] The second terminal of the first capacitor C112 is the input terminal of the filter circuit 32.

[0053] The second terminal of the first resistor R108 is grounded.

[0054] For example, such as Figure 4 As shown, the filter circuit 32 includes a first resistor R108 and a first capacitor C112; the first end of the first resistor R108 and the first end of the first capacitor C112 are connected to form the output terminal of the filter circuit 32. The second end of the first capacitor C112 is the input terminal of the filter circuit 32. The second end of the first resistor R108 is grounded.

[0055] The first resistor and the first capacitor form an RC filter circuit 32. This filter circuit 32 has a simple structure and is easy to implement. It can effectively reduce testing costs while achieving the filtering effect.

[0056] In one possible implementation, each set of data transmission ends of any module under test is used to transmit differential data, including a forward data transmission end and a reverse data transmission end.

[0057] like Figure 5 As shown, the switching circuit 31 includes a first switching sub-circuit 51 and a second switching sub-circuit 52. The first end of the first switching sub-circuit 51 and the first end of the second switching sub-circuit 52 form the first end of the corresponding switching unit. The first end of the first switching sub-circuit 51 and the first end of the second switching sub-circuit 52 are respectively connected to the forward data transmission end and the reverse data transmission end in the same group of data transmission ends of the module under test. The second end of the first switching sub-circuit 51 and the second end of the second switching sub-circuit 52 form the second end of the corresponding switching unit. The control end of the first switching sub-circuit 51 and the control end of the second switching sub-circuit 52 are connected to form the control end of the corresponding switching unit.

[0058] Each of the switching sub-circuits includes an NMOS device, a first bias circuit, and a second bias circuit.

[0059] The first source of the NMOS device is the first terminal of the corresponding switching sub-circuit, which is connected to the first terminal of the first bias circuit and the positive or negative data transmission terminal of a set of data transmission terminals of the module under test. The second source is the second terminal of the corresponding switching sub-circuit, which is connected to the first terminal of the second bias circuit. The gate is the control terminal of the corresponding switching sub-circuit.

[0060] The second terminal of the first bias circuit and the second terminal of the second bias circuit are both grounded.

[0061] Optionally, the NMOS device included in any switching sub-circuit can be a dual-transistor NMOS device. By controlling the gate level of the dual-transistor NMOS device, the NMOS transistor is made to be in the on or off state, thereby realizing the line layer switching function and achieving the switching effect.

[0062] The bias circuit can specifically be a bias resistor. By setting the bias circuit, a suitable DC operating point can be established for the NMOS transistor, ensuring that the drain or source of the NMOS transistor is at a stable low potential, thereby guaranteeing that the NMOS transistor is in the off state when the gate is at a low potential.

[0063] For example, such as Figure 4 As shown, the first switching sub-circuit 51 includes an NMOS device Q1, which is a dual-transistor NMOS device. The first bias circuit includes a resistor R105, and the second bias circuit includes a resistor R109.

[0064] Optionally, the NMOS device is a high-frequency NMOS device.

[0065] Since the 1394 bus signal is a high-speed, wideband square wave signal, the frequency of the square wave signal reaches 100MHz for a typical 1394 bus. This requires the signal switch to have low conduction loss, low distortion, wide bandwidth, low group delay ripple, and sufficiently high turn-off loss to minimize signal leakage. This application adopts an analog RF wideband circuit scheme, selects suitable high-frequency switching NMOS devices, ensures signal waveform quality, and passes environmental reliability tests.

[0066] Any switching sub-circuit may include multiple NMOS devices. In one possible implementation, the NMOS devices include a first NMOS transistor and a second NMOS transistor.

[0067] The source of the first NMOS transistor is the input terminal of the corresponding switching sub-circuit, and is connected to the first terminal of the first bias circuit, the positive data transmission terminal or the reverse data transmission terminal in a set of data transmission terminals of the module under test, respectively. The gate is connected to the output terminal of the filter circuit 32, and the drain is connected to the drain of the second NMOS transistor.

[0068] The gate of the second NMOS transistor is connected to the output terminal of the filter circuit 32, and the source is the output terminal of the corresponding switching sub-circuit, which is connected to the first terminal of the second bias circuit.

[0069] Optionally, in order to reduce circuit size and cost, the various switching sub-circuits belonging to the same switching circuit 31 can share the second bias circuit. The various switching sub-circuits belonging to the same switching unit can also share the second bias circuit.

[0070] For example, see Figure 4Taking the first switching sub-circuit 51 included in the first switching sub-module 111 as an example, it specifically includes NMOS devices Q1A and Q1B, and bias resistors R105 and R109; the second switching sub-circuit 52 specifically includes NMOS devices Q2A and Q2B, and bias resistors R119 and R120. The first switching sub-circuit 51 included in the switching circuit 31 of the second switching unit 22 in the first switching sub-module 111 specifically includes NMOS devices Q3A and Q3B, and bias resistors R106 and R109; the second switching sub-circuit 52 specifically includes NMOS devices Q4A and Q4B, and bias resistors R115 and R120.

[0071] Optionally, any switching sub-circuit may also include a second resistor and a third resistor.

[0072] The gate of the first NMOS transistor is connected to the first end of the second resistor, and the second end of the first resistor is connected to the output of the filter circuit 32.

[0073] The gate of the second NMOS transistor is connected to the first end of the third resistor, and the second end of the second resistor is connected to the output of the filter circuit 32.

[0074] For example, see [link to example]. Figure 4 As shown, the switch sub-circuit includes a second resistor R308 and a third resistor R107.

[0075] The second and third resistors are current-limiting resistors, used to protect the control terminal of the NMOS transistor, thereby reducing current and energy consumption while improving device safety and reliability.

[0076] This application utilizes a packaged dual-transistor NMOS transistor or an NMOS pair design to make the circuit suitable for transmitting and receiving data in both directions.

[0077] Taking the first switch sub-circuit 51 as an example, when the first switch sub-circuit 51 is disabled and the second switch sub-circuit 52 is enabled, that is, when the control signal SEL1 is low and the control signal SEL2 is high, the module under test 2 performs data transmission and reception. Figure 6In the circuit shown, the signal flow during transmission is as follows: The signal transmitted by module 2 flows through the source of the NMOS transistor on the "B" side of NMOS devices Q3 and Q4 (PIN4 of NMOS devices Q3 and Q4), through the diode, and into the drain D (PIN3 of NMOS devices Q3 and Q4). The drains D on the "A" side and the "B" side of the dual-transistor NMOS devices Q3 and Q4 are directly connected, and then flow out through the drain of the "A" side of the NMOS transistor on the "A" side of Q3 and Q4 (PIN6 of NMOS devices Q3 and Q4) to the source S (PIN1 of NMOS devices Q3 and Q4). Thus, the signal flows out to the output terminal. However, at this time, the output terminal is connected to the source S (PIN1 of NMOS devices Q1 and Q2) on the "A" side. The signal can flow from the source of Q1 and Q2 through the body diode to the drain D (PIN6 of NMOS devices Q1 and Q2). The drains D on the "A" and "B" sides of the dual-transistor NMOS devices Q1 and Q2 are also directly connected. However, SEL1 is low, and Q1 and Q2 are in the off state. Therefore, the signal cannot flow to the subsequent stage, i.e., the transmitting end of module 1 under test. The signal flow during the receiving process is as follows: data is input from the port to NMOS device Q1. 1. The source of the NMOS transistor on the "A" side of Q12 (PIN1 of NMOS devices Q11 and Q12) flows into the drain D (PIN6 of NMOS devices Q11 and Q12) through the body diode. The drains D on the "A" side and "B" side of the dual NMOS devices Q11 and Q12 are directly connected, and then flow out to the source S (PIN4 of NMOS devices Q11 and Q12) through the drain of the "B" side of the open NMOS transistors Q11 and Q12 (PIN3 of NMOS devices Q11 and Q12). Thus, the signal flows into the receiving end of the module under test 2. However, at this time, the input at the port is connected to the source S (PIN1 of NMOS devices Q9 and Q10) on the "A" side. The signal can flow from the source of Q9 and Q10 through the body diode to the drain D (PIN6 of NMOS devices Q9 and Q10). The drains D on the "A" and "B" sides of the dual-transistor NMOS devices Q9 and Q10 are also directly connected. However, SEL1 is low, and Q9 and Q10 are in the off state. Therefore, the signal cannot flow to the subsequent stage, i.e., the receiving end of the module under test 1. When the first switching sub-circuit 51 is enabled, i.e., when the control signal SEL1 is high, its internal NMOS device is turned on. The module under test 1 can communicate whether sending or receiving, similar to the above process, and will not be described in detail here.

[0078] like Figure 7 As shown, in one possible implementation, the gating module 12 includes a transmission circuit, a transmission line, and a control unit.

[0079] The control unit is used to transmit the received external control signals to the output of the transmission circuit via a transmission line.

[0080] The output terminals of the transmission circuit include a first output terminal and a second output terminal, which are the first and second terminals of the gating module 12, respectively. The transmission circuit is used to control the output of the first or second output terminal of the transmission circuit to output a control signal according to the signal from the control terminal of the transmission circuit.

[0081] Specifically, the control unit can be located outside the testing environment, such as a high or low temperature chamber or a vibration table.

[0082] Alternatively, the control unit can be any device capable of emitting at least two signals, such as a rotary switch.

[0083] This setting enables remote control of the switching module.

[0084] In one possible implementation, the transmission circuit includes a first voltage pull-down circuit, a second voltage pull-down circuit, a first current limiting circuit, a second current limiting circuit, a first surge suppression circuit, a second surge suppression circuit, a filter protection circuit, and a connector.

[0085] The first terminal of the first voltage pull-down circuit is the first output terminal of the transmission circuit, and the second terminal is grounded.

[0086] The first terminal of the first current limiting circuit is connected to the first terminal of the first voltage pull-down circuit, and the second terminal is connected to the first terminal of the first surge suppression circuit and the second terminal of the connector, respectively.

[0087] The second terminal of the first surge suppression circuit is grounded.

[0088] The first terminal of the second voltage pull-down circuit is the second output terminal of the transmission circuit, and the second terminal is grounded.

[0089] The first terminal of the second current limiting circuit is connected to the first terminal of the second voltage pull-down circuit, and the second terminal is connected to the first terminal of the second surge suppression circuit and the third terminal of the connector, respectively.

[0090] The second terminal of the second surge suppression circuit is grounded.

[0091] The first end of the filter protection circuit is connected to the power supply, and the second end is connected to the first end of the connector.

[0092] Connectors are used to connect transmission lines.

[0093] like Figure 8 As shown, exemplarily, the first voltage pull-down circuit in the transmission circuit includes a resistor R296; the second voltage pull-down circuit includes a resistor R297; the first current limiting circuit includes a resistor R286; the second current limiting circuit includes a resistor R285; the first surge suppression circuit includes a TVS diode D7; the second surge suppression circuit includes a TVS diode D8; the filter protection circuit includes a ferrite bead FB14 and a diode D5; and the connectors are J26 and J27.

[0094] Among them, the FB14 ferrite bead is used to filter and absorb some power supply interference, and the D5 diode is used to prevent external voltage from entering the module under test and affecting the power supply.

[0095] In one possible implementation, a power supply module is also included.

[0096] The power module includes a dual-channel DC-DC power chip with enable function, a third voltage pull-down circuit, and a fourth voltage pull-down circuit.

[0097] The first enable terminal of the power chip is connected to the first terminal of the third voltage pull-down circuit and the first terminal of the gating module 12, respectively. The second enable terminal is connected to the first terminal of the fourth voltage pull-down circuit and the second terminal of the gating module 12, respectively. The first voltage output terminal is connected to the power supply terminal of the first module under test 200, and the second voltage output terminal is connected to the power supply terminal of the second module under test 300. The first enable terminal is used to control the output state of the first voltage output terminal, and the second enable terminal is used to control the output state of the second voltage output terminal.

[0098] The second terminal of the third voltage pull-down circuit and the second terminal of the fourth voltage pull-down circuit are grounded.

[0099] Optionally, the voltage pull-down circuit includes a pull-down resistor.

[0100] For example, such as Figure 9 As shown, the power module includes a dual-channel DC-DC power chip U9 with enable function, and pull-down circuits R1 and R9. The enable pins RUN1 and RUN2 are pulled low by R1 and R9 by default, and are in a disabled state with no output. When pin RUN1 or RUN2 is enabled by a high level from network SEL1 or SEL2, the corresponding output terminal outputs power, powering on the connected module under test.

[0101] To clearly describe the operation of the circuit provided in this application, the following description uses the control unit 122 as a rotary switch as an example, and further explains it in conjunction with Table 1. Figure 6 The transmission and reception test procedures corresponding to the circuit shown are as follows: When the rotary switch is rotated 45° to connect C-PIN1, SEL1 goes high, enabling the power supply chip RUN1 and powering on module 1 under test. Simultaneously, the gates of Q1 and Q2 go high, making their sources and drains conduct, and 1394_TX0-_1 / 1394_TX0+_1 outputs to TX0- / TX0+. However, at this time, SEL2 goes low, and power supply module RUN2 goes low, so module 2 under test is not powered, and 1394_TX0-_2 / 1394_TX0+_2 has no signal output. At the same time, the gates of Q3 and Q4 go low, turning off their sources and drains, and 1394_TX0-_2 / 1394_TX0+_2 is not conducting with TX0- / TX0+. This allows the transmit port of module 1 under test to connect to the external 1394 analyzer. Meanwhile, SEL1 is high, and the gates of Q9 and Q10 are high, causing the source and drain of Q9 and Q10 to conduct, and RX0- / RX0+ output to 1394_RX0-_1 / 1394_RX0+_1. However, at this time, SEL2 is low, the power supply module RUN2 is low, the module under test 2 is not powered, and 1394_RX0-_2 / 1394_RX0+_2 does not receive signal input; at the same time, the gates of Q11 and Q12 are low, the source and drain of Q11 and Q12 are off, and 1394_RX0-_2 / 1394_RX0+_2 and RX0- / RX0+ are not conducting. Thus, the receiving port of the module under test 1 is connected to the external 1394 analyzer. At this point, the transmit / receive signal terminals of module 1 under test are connected to the transmit / receive signal terminals of the external 1395 analyzer; the transmit / receive signal terminals of module 2 under test are disconnected from the transmit / receive signal terminals of the external 1395 analyzer.

[0102] When the rotary switch is rotated 135° to connect C-PIN3, SEL2 goes high, enabling the power supply chip RUN2 and powering on module 2 under test. Simultaneously, the gates of Q3 and Q4 go high, conducting their sources and drains, and 1394_TX0-_2 / 1394_TX0+_2 outputs to TX0- / TX0+. However, at this time, SEL1 is low, and power supply module RUN1 is low, so module 1 under test is not powered, and 1394_TX0-_1 / 1394_TX0+_1 has no signal output. Meanwhile, the gates of Q1 and Q2 go low, turning off their sources and drains, and 1394_TX0-_1 / 1394_TX0+_1 is not conducting with TX0- / TX0+. This allows the port of module 2 under test to connect to the external 1394 analyzer. Meanwhile, SEL2 is high, enabling power chip RUN2 and powering on module 2 under test. Simultaneously, the gates of Q11 and Q12 are high, causing their sources and drains to conduct, and RX0- / RX0+ outputs to 1394_RX0-_2 / 1394_RX0+_2. However, at this time, SEL1 is low, power module RUN1 is low, module 1 under test is not powered, and 1394_RX0-_1 / 1394_RX0+_1 does not receive signal input. At the same time, the gates of Q9 and Q10 are low, turning off their sources and drains, and 1394_RX0-_1 / 1394_RX0+_1 and RX0- / RX0+ are not connected. This achieves the disconnection of the transceiver signal terminals of module 1 under test from the external 1395 analyzer, while connecting the transceiver signal terminals of module 2 under test to the external 1395 analyzer.

[0103] Table 1 This application also provides a testing device, including any of the switching circuits provided in the above embodiments.

[0104] In one possible implementation, the test equipment also includes a signal analysis device; the signal analysis device is connected to the output of the switching circuit.

[0105] Signal analysis equipment is used to perform data analysis on received test data.

[0106] Specifically, signal analysis equipment may include a signal analyzer and a controller, wherein the signal analyzer may be a 1394 analyzer.

[0107] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0108] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A switching circuit, wherein the switching circuit is connected to a module under test, the module under test comprising at least a first module under test and a second module under test; each module under test comprising at least two sets of data transmission terminals; characterized in that, The switching circuit includes: At least one switching module and a gating module; The switching module includes a first switching submodule and a second switching submodule; The first end of the first switching submodule is connected to a set of data transmission terminals of the first module under test, and the second end is connected to a set of data transmission terminals of the second module under test. The first end of the second switching submodule is connected to another set of data transmission ends of the first module under test, and the second end is connected to another set of data transmission ends of the second module under test. The fifth terminal of the gating module is used to receive external control signals. The gating module is used to control the first switching submodule and the second switching submodule to be connected to the first tested module simultaneously, or to control the first switching submodule and the second switching submodule to be connected to the second tested module simultaneously, according to the received external control signals.

2. The circuit according to claim 1, characterized in that, The third, fourth, and fifth terminals of the first switching submodule are respectively connected to the first, second, and third terminals of the gating module; the third, fourth, and fifth terminals of the second switching submodule are respectively connected to the first, second, and fourth terminals of the gating module. Each of the switching submodules includes a switching unit, and the switching unit includes a first switching unit and a second switching unit; The first end of the first switching unit is the first end of the corresponding switching submodule, the second end is the fifth end of the corresponding switching submodule, and the control end is the third end of the corresponding switching submodule. The first switching unit is used to connect or disconnect the first end and the fifth end of the corresponding switching submodule according to the signal from the control end of the first switching unit. The first end of the second switching unit is the second end of the corresponding switching submodule, the second end is the fifth end of the corresponding switching submodule, and the control end is the fourth end of the corresponding switching submodule. The second switching unit is used to connect or disconnect the second and fifth ends of the corresponding switching submodule according to the signal from the control end of the first switching unit.

3. The circuit according to claim 2, characterized in that, Each switching unit includes a switching circuit and a filtering circuit; The first terminal of the switching circuit is the first terminal of the corresponding switching unit, the second terminal is the second terminal of the corresponding switching unit, and the control terminal is connected to the output terminal of the filter circuit. The input terminal of the filter circuit is the control terminal of the corresponding switching unit; The filtering circuit is used to filter the signal at the input terminal of the filtering circuit and output it to the control terminal of the switching circuit; the switching circuit is used to connect or disconnect the first and second terminals of the corresponding switching unit according to the signal at the control terminal of the switching circuit.

4. The circuit according to claim 3, characterized in that, Each set of data transmission terminals of any module under test is used to transmit differential data, including a forward data transmission terminal and a reverse data transmission terminal; The switching circuit includes a first switching sub-circuit and a second switching sub-circuit. The first end of the first switching sub-circuit and the first end of the second switching sub-circuit form the first end of the corresponding switching unit. The first end of the first switching sub-circuit and the first end of the second switching sub-circuit are respectively connected to the forward data transmission end and the reverse data transmission end in the same group of data transmission ends of the module under test. The second end of the first switching sub-circuit and the second end of the second switching sub-circuit form the second end of the corresponding switching unit. The control end of the first switching sub-circuit and the control end of the second switching sub-circuit are connected to form the control end of the corresponding switching unit. Each of the switching sub-circuits includes an NMOS device, a first bias circuit, and a second bias circuit; The first source of the NMOS device is the first terminal of the corresponding switching sub-circuit, which is connected to the first terminal of the first bias circuit and the positive data transmission terminal or the reverse data transmission terminal in a set of data transmission terminals of the module under test. The second source is the second terminal of the corresponding switching sub-circuit, which is connected to the first terminal of the second bias circuit. The gate is the control terminal of the corresponding switching sub-circuit. Both the second terminal of the first bias circuit and the second terminal of the second bias circuit are grounded.

5. The circuit according to any one of claims 1-4, characterized in that, The gating module includes a transmission circuit, a transmission line, and a control unit; The control unit is used to transmit the received external control signals to the output terminal of the transmission circuit through the transmission line; The output terminals of the transmission circuit include a first output terminal and a second output terminal, which are respectively the first terminal and the second terminal of the gating module; the transmission circuit is used to control the first output terminal or the second output terminal of the transmission circuit to output a control signal according to the signal of the control terminal of the transmission circuit.

6. The circuit according to claim 5, characterized in that, The transmission circuit includes a first voltage pull-down circuit, a second voltage pull-down circuit, a first current limiting circuit, a second current limiting circuit, a first surge suppression circuit, a second surge suppression circuit, a filter protection circuit, and a connector; The first terminal of the first voltage pull-down circuit is the first output terminal of the transmission circuit, and the second terminal is grounded; The first terminal of the first current limiting circuit is connected to the first terminal of the first voltage pull-down circuit, and the second terminal is connected to the first terminal of the first surge suppression circuit and the second terminal of the connector, respectively. The second terminal of the first surge suppression circuit is grounded; The first terminal of the second voltage pull-down circuit is the second output terminal of the transmission circuit, and the second terminal is grounded; The first terminal of the second current limiting circuit is connected to the first terminal of the second voltage pull-down circuit, and the second terminal is connected to the first terminal of the second surge suppression circuit and the third terminal of the connector, respectively. The second terminal of the second surge suppression circuit is grounded; The first end of the filter protection circuit is connected to the power supply, and the second end is connected to the first end of the connector. The connector is used to connect the transmission line.

7. The circuit according to claim 1, characterized in that, It also includes a power module; The power module includes a dual-channel DC-DC power chip with an enable function, a third voltage pull-down circuit, and a fourth voltage pull-down circuit. The first enable terminal of the power chip is connected to the first terminal of the third voltage pull-down circuit and the first terminal of the gating module, respectively. The second enable terminal is connected to the first terminal of the fourth voltage pull-down circuit and the second terminal of the gating module, respectively. The first voltage output terminal is connected to the power supply terminal of the first module under test, and the second voltage output terminal is connected to the power supply terminal of the second module under test. The first enable terminal is used to control the output state of the first voltage output terminal, and the second enable terminal is used to control the output state of the second voltage output terminal. The second terminal of the third voltage pull-down circuit and the second terminal of the fourth voltage pull-down circuit are grounded.

8. The circuit according to any one of claims 1-4 or 7, characterized in that, Any switching submodule includes a 1394 bus interface, wherein the first end of the switching submodule is the first differential data terminal of the 1394 bus interface, and the second end is the second differential data terminal of the 1394 bus interface.

9. A testing device, characterized in that, Includes the switching circuit as described in any one of claims 1-8.

10. The device according to claim 9, characterized in that, It also includes signal analysis equipment; The signal analysis device is connected to the output terminal of the switching circuit and is used to analyze the test data output by the switching circuit.

Images