Power supply device and testing machine

Abstract

The application relates to a power supply device and a testing machine, the power supply device comprising: a capacitor plate connected to a first power supply end and connected to a power supply plate through a power cable; the capacitor plate stores energy according to the power supply connected to the first power supply end, and delivers the stored energy to the power supply plate through the power cable; the power supply plate is connected to a second power supply end, the power cable and a device to be tested, and the power supply plate selects a power supply connected to the second power supply end or energy transmitted by the power cable to supply power to the device to be tested. Through the external capacitor plate, the space required by the capacitor can be expanded to the outside of the power supply plate, is not limited by the volume of a single plate, breaks through the limitation of the energy density of a single plate, and facilitates the voltage and current specification upgrade of the power supply device.

Description

Technical Field

[0001] This application relates to the field of semiconductor testing technology, and in particular to a power supply device and a testing machine. Background Technology

[0002] With the rapid development of new energy and communication electronic products, the demand for high-current testing of power semiconductors and power ICs is expanding. As an indispensable part of integrated circuit ATE (Automatic Test Equipment) testing, the VI source is used to provide test stimulus to the device under test (DUT). To meet these needs, the design of a high-current VI source is particularly important.

[0003] In ATE equipment, the utilization rate of VI source hardware resources is a crucial indicator. Traditional power supply boards cannot be developed to meet the testing needs of high-power products based on existing models. Their limited power density restricts the placement of more power devices on the board, significantly limiting the development of new boards. Overcoming the energy density limitations of traditional power supply boards is a pressing issue that needs to be addressed. Utility Model Content

[0004] Therefore, it is necessary to provide a power supply device and testing machine that can overcome the energy density limitation to address the above problems.

[0005] The first aspect of this application provides a power supply device, comprising:

[0006] A capacitor board is connected to a first power supply terminal and to a power supply board via a power cable; the capacitor board stores energy based on the power supplied to the first power supply terminal and transmits the stored energy to the power supply board via the power cable.

[0007] The power board is connected to the second power terminal, the power cable, and the device under test. The power board selects the power source connected to the second power terminal or the energy transmitted by the power cable to power the device under test.

[0008] In one embodiment, the capacitor board includes a first power module, an energy storage module, and a discharge module. The first power module is connected to the first power supply terminal and the energy storage module, and the discharge module is connected to the energy storage module and the power cable. The first power module converts the power supplied to the first power supply terminal and then supplies it to the energy storage module. The discharge module supplies the energy stored in the energy storage module to the power board through the power cable.

[0009] In one embodiment, the first power module includes a transformer, a rectifier bridge, a BUCK circuit, and an LDO circuit connected in sequence. The transformer is connected to the first power supply terminal, and the LDO circuit is connected to the energy storage module.

[0010] In one embodiment, the energy storage module includes a capacitor assembly connected to the LDO circuit, the capacitor assembly being composed of a plurality of capacitors connected in series and / or in parallel.

[0011] In one embodiment, the discharge module includes a discharge switch unit and an output switch unit. The discharge switch unit is connected to the capacitor assembly and the output switch unit, and the output switch unit is connected to the power cable. When the discharge switch unit is turned on and the output switch unit is turned off, the energy stored in the capacitor assembly is discharged through the discharge switch unit. When the discharge switch unit is turned off and the output switch unit is turned on, the energy of the energy storage module is delivered to the power cable through the output switch unit.

[0012] In one embodiment, there are two of each of the transformer, rectifier bridge, BUCK circuit, LDO circuit, capacitor assembly, and discharge switch unit. The transformer, rectifier bridge, BUCK circuit, LDO circuit, capacitor assembly, and discharge switch unit are connected in sequence, and the output switch unit is connected to each discharge switch unit and the power cable.

[0013] In one embodiment, one of the discharge switch units includes a switch S1 and a discharge resistor R1, another discharge switch unit includes a switch S2 and a discharge resistor R2, and the output switch unit includes a switch S3, a switch S4 and a switch S5.

[0014] The first end of switch S1 is connected to one end of the corresponding capacitor assembly and one end of the corresponding LDO circuit. The second end of switch S1 is connected to the first end of discharge resistor R1. The second end of discharge resistor R1 is connected to the other end of the corresponding capacitor assembly and the other end of the corresponding LDO circuit. The first end of switch S2 is connected to one end of the corresponding capacitor assembly, the second end of discharge resistor R1, and one end of the corresponding LDO circuit. The second end of switch S2 is connected to the first end of discharge resistor R2. The second end of discharge resistor R2 is connected to the other end of the corresponding capacitor assembly and the other end of the corresponding LDO circuit.

[0015] The first end of switch S3 is connected to the first end of switch S1, the second end of switch S3 is connected to the positive wire in the power cable, the first end of switch S4 is connected to the second end of discharge resistor R1 and the first end of switch S2, the second end of switch S4 is connected to the ground wire in the power cable, the first end of switch S5 is connected to the second end of discharge resistor R2, and the second end of switch S5 is connected to the negative wire in the power cable.

[0016] In one embodiment, the capacitor board further includes a first control module, which is connected to a first control signal terminal, the first power supply module, and the discharge module.

[0017] In one embodiment, the first control module includes a logic circuit and a driver, the logic circuit being connected to the first control signal terminal and the driver, and the driver being connected to the first power module and the discharge module.

[0018] In one embodiment, the power board includes a second power module, a bus selection module, and a power amplifier module. The second power module is connected to a second power supply terminal and the bus selection module. The bus selection module is connected to the power cable and the power amplifier module. The power amplifier module is connected to the device under test (DUT). The second power module converts the voltage of the power supplied to the second power supply terminal and then supplies it to the bus selection module. The bus selection module selects to supply power to the DUT using either the voltage converted by the second power module or the energy supplied by the power cable, and adjusts the voltage using the power amplifier module.

[0019] In one embodiment, the bus selection module includes switches S6, S7, S8, and S9. The first end of switch S6 is connected to the positive output of the second power module, and the second end of switch S6 is connected to the positive bus of the power amplifier module. The first end of switch S7 is connected to the negative output of the second power module, and the second end of switch S7 is connected to the negative bus of the power amplifier module. The first end of switch S8 is connected to the positive wire in the power cable, and the second end of switch S8 is connected to the positive bus of the power amplifier module. The first end of switch S9 is connected to the negative wire in the power cable, and the second end of switch S9 is connected to the negative bus of the power amplifier module.

[0020] In one embodiment, the power board further includes a second control module, which is connected to a second control signal terminal, the second power module, the bus selection module, and the power amplifier module.

[0021] A second aspect of this application provides a testing machine including the power supply device described above.

[0022] The aforementioned power supply unit and testing machine include: a capacitor board connected to a first power supply terminal and connected to a power board via a power cable; the capacitor board stores energy based on the power supplied to the first power supply terminal and transmits the stored energy to the power board via the power cable; the power board connects to a second power supply terminal, the power cable, and the device under test (DUT); the power board selects either the power supplied to the second power supply terminal or the energy transmitted via the power cable to power the DUT. By using an external capacitor board, the space required for the capacitors can be expanded outside the power board, overcoming the limitations of single-board volume and energy density, and facilitating upgrades to the voltage and current specifications of the power supply unit. Attached Figure Description

[0023] Figure 1 This is a structural block diagram of the power supply device in one embodiment;

[0024] Figure 2 This is a structural block diagram of the capacitor plate in one embodiment;

[0025] Figure 3 This is a structural block diagram of the power board in one embodiment;

[0026] Figure 4 This is a schematic diagram of the capacitor plate in one embodiment;

[0027] Figure 5 The diagram shows the structure of the power board in one embodiment. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0030] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0031] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated feature, whole, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, operations, components, parts, or combinations thereof.

[0032] In one embodiment, such as Figure 1 As shown, a power supply device is provided, including a capacitor board 100 and a power board 200. The capacitor board 100 is connected to a first power supply terminal and is connected to the power board 200 via a power cable. The power board 200 is connected to a second power supply terminal, the power cable, and a device under test (DUT). The capacitor board 100 stores energy according to the power supply connected to the first power supply terminal and transmits the stored energy to the power board 200 via the power cable. The power board 200 selects the power supply connected to the second power supply terminal or the energy transmitted via the power cable to supply power to the DUT.

[0033] Both the first and second power supply terminals can be connected to 220V AC power. They can be the same terminal or two separate terminals. The device under test (DUT) can be a chip under test or other electronic devices. The power board 200 is specifically a VI power supply board. Depending on the specific requirements, the power board 200 can select either the power source connected to the second power supply terminal or the energy transmitted via a power cable to power the DUT, thus meeting different testing needs. Furthermore, the capacitor bank 100 is connected to the first control signal terminal, storing and outputting energy based on the control signal received at the first control signal terminal. The power board 200 can also be connected to the second control signal terminal, selecting either the power source connected to the second power supply terminal or the energy transmitted via a power cable to power the DUT based on the control signal received at the second control signal terminal.

[0034] As the voltage and current specifications of the Device Under Test (DUT) increase, the voltage and current output specifications of the original VI source board also need to be improved. This typically requires accommodating more power devices, but this is limited by the original board's size, primarily in its area and height, which limits the number of power devices and thus restricts the single-board output capability. Capacitors are usually the most space-consuming components in a power supply unit; therefore, using an external capacitor board 100 can extend the space required for the bus capacitors to the outside of the power board 200, removing the single-board energy density limitation.

[0035] The specific structure of capacitor plate 100 is not unique; in one embodiment, such as... Figure 2As shown, the capacitor board 100 includes a first power module 110, an energy storage module 120, and a discharge module 130. The first power module 110 is connected to a first power supply terminal and the energy storage module 120, and the discharge module 130 is connected to the energy storage module 130 and a power cable. The first power module 110 converts the voltage of the power supplied to the first power supply terminal and delivers it to the energy storage module 120. The discharge module 130 delivers the energy stored in the energy storage module 120 to the power board 200 through the power cable. Further, the capacitor board 100 also includes a first control module 140, which is connected to a first control signal terminal, the first power module 110, and the discharge module 130. The first power module 110 converts the voltage of the power supplied to the first power supply terminal and delivers it to the energy storage module 120. The discharge module 130 outputs the energy from the energy storage module 120 through the power cable. The first power module 110 enables itself and the discharge module 130 according to the control signal supplied to the first control signal terminal.

[0036] The specific structure of the power board 200 is not unique; in one embodiment, such as... Figure 2 As shown, the power board 200 includes a second power module 210, a bus selection module 220, and a power amplifier module 230. The second power module 210 connects to the second power supply terminal and the bus selection module 220. The bus selection module 220 connects to the power cable and the power amplifier module 230. The power amplifier module 230 connects to the device under test (DUT). The second power module 210 converts the voltage of the power supplied to the second power supply terminal and then sends it to the bus selection module 220. The bus selection module 220 selects whether to use the voltage converted by the second power module 210 or the energy supplied by the power cable, and after adjustment by the power amplifier module 230, supplies power to the DUT. When the power board 200 is a VI source board, the power amplifier module 230 is a VI source amplifier module.

[0037] Furthermore, the power board 200 also includes a second control module 240, which is connected to a second control signal terminal, a second power module 210, a bus selection module 220, and a power amplifier module 230. The second control module 240 controls the operation of the second power module 210, the bus selection module 220, and the power amplifier module 230 based on the control signal input to the second control signal terminal. The second power module 210 converts the power input to the second power terminal into a voltage and sends it to the bus selection module 220. The bus selection module 220 selects the power supply for the second power module 210 and the power cables according to the control of the second control module 240, and then sends the power to the power amplifier module 230.

[0038] In one embodiment, such as Figure 4As shown, the first power module 110 includes a transformer T, a rectifier bridge ZD, a BUCK (step-down converter) circuit, and an LDO (linear voltage regulator) circuit connected in sequence. The transformer T is connected to the first power supply terminal, and the LDO circuit is connected to the energy storage module 120. The rectifier bridge ZD can be a half-bridge rectifier or a full-bridge rectifier circuit. In this embodiment, the rectifier bridge ZD is a full-bridge rectifier circuit composed of four diodes. The AC power input to the first power supply terminal is converted by the transformer T and then rectified by the rectifier bridge ZD. The resulting DC power passes through the BUCK circuit and the LDO circuit before being delivered to the energy storage module 120 for storage. The energy storage module 120 specifically includes a capacitor assembly connected to the LDO circuit. The capacitor assembly consists of several capacitors connected in series and / or in parallel. In this embodiment, the capacitor assembly uses a structure of parallel capacitors followed by series capacitors, with both ends of the capacitor assembly connected to the two output terminals of the LDO circuit.

[0039] Furthermore, the discharge module 130 includes a discharge switch unit 132 and an output switch unit 134. The discharge switch unit 132 is connected to the capacitor assembly and the output switch unit 134, and the output switch unit 134 is connected to the power cable. When the discharge switch unit 132 is turned on and the output switch unit 134 is turned off, the energy stored in the capacitor assembly is discharged through the discharge switch unit 132. When the discharge switch unit 132 is turned off and the output switch unit 134 is turned on, the energy of the energy storage module 120 is delivered to the power cable through the output switch unit 134.

[0040] In this embodiment, the transformer T, rectifier bridge ZD, BUCK circuit, LDO circuit, capacitor assembly, and discharge switch unit 132 constitute an energy storage channel. The capacitor plate 100 can have one, two, or more energy storage channels. In this embodiment, there are two transformer T, rectifier bridge ZD, BUCK circuit, LDO circuit, capacitor assembly, and discharge switch unit 132. These components are connected sequentially, and the output switch unit 134 connects each discharge switch unit 132 and the power cable. Using two energy storage channels for power supply increases the output power of the capacitor plate 100 and adapts to different testing requirements.

[0041] Specifically, in the two discharge switch units 132, one discharge switch unit 132 includes a switch S1 and a discharge resistor R1, and the other discharge switch unit 132 includes a switch S2 and a discharge resistor R2. The output switch unit 134 includes switches S3, S4, and S5. The power cable includes a positive line CAP_BUS+, a ground line CAP_BUS_GND, and a negative line CAP_BUS-. The first end of switch S1 is connected to one end of the corresponding capacitor component and one end of the corresponding LDO circuit. The second end of switch S1 is connected to the first end of the discharge resistor R1, and the second end of the discharge resistor R1 is connected to the other end of the corresponding capacitor component and the other end of the corresponding LDO circuit. The first end of switch S2 is connected to one end of the corresponding capacitor component, the second end of the discharge resistor R1, and one end of the corresponding LDO circuit. The second end of switch S2 is connected to the first end of the discharge resistor R2, and the second end of the discharge resistor R2 is connected to the other end of the corresponding capacitor component and the other end of the corresponding LDO circuit.

[0042] The first terminal of switch S3 is connected to the first terminal of switch S1. The second terminal of switch S3 is connected to the positive line CAP_BUS+ in the power cable. The first terminal of switch S4 is connected to the second terminal of discharge resistor R1 and the first terminal of switch S2. The second terminal of switch S4 is connected to the ground line CAP_BUS_GND in the power cable. The first terminal of switch S5 is connected to the second terminal of discharge resistor R2. The second terminal of switch S5 is connected to the negative line CAP_BUS- in the power cable.

[0043] Switches S1 to S5 can be control switches such as selection relays, and their on / off control is performed by the first control module 140. When the capacitor board 100 is powered off, switches S1 and S2 are closed, and switches S3 to S5 are open, and the energy of the energy storage module 120 is consumed through discharge resistors R1 and R2; when the capacitor board 100 needs to output, switches S3, S4, and S5 are closed, and switches S1 and S2 are closed, and the energy of the energy storage module 120 is output through the power cable.

[0044] Continue to refer to Figure 4 The first control module 140 includes a logic circuit 142 and a driver 144. The logic circuit 142 is connected to a first control signal terminal and the driver 144. The driver 144 is connected to the first power module 110 and the discharge module 130. Specifically, the driver 144 can be connected to the control terminals of switches S1 to S5 in the discharge module 130. The control signal input to the first control signal terminal is converted by the logic circuit 142 and output by the driver to control the enabling and disabling of the power module 110, as well as the closing and opening of switches S1 to S5.

[0045] In one embodiment, such as Figure 5As shown, the bus selection module 220 includes switches S6, S7, S8, and S9. The first terminal of switch S6 is connected to the positive output of the second power module 210, and the second terminal of switch S6 is connected to the positive bus BUS+ of the power amplifier module 230. The first terminal of switch S7 is connected to the negative output of the second power module 210, and the second terminal of switch S7 is connected to the negative bus BUS- of the power amplifier module 230. The first terminal of switch S8 is connected to the positive wire CAP_BUS+ in the power cable, and the second terminal of switch S8 is connected to the positive bus BUS+ of the power amplifier module 230. The first terminal of switch S9 is connected to the negative wire CAP_BUS- in the power cable, and the second terminal of switch S9 is connected to the negative bus BUS- of the power amplifier module 230. The ground wire CAP_BUS_GND in the power cable is grounded.

[0046] Switches S6, S7, S8, and S9 can also be control switches such as relays. The second control module 240 connects to the control terminals of switches S6, S7, S8, and S9 to control the on / off state of each switch. When power is supplied from the power board 200, switches S6 and S7 are closed, and switches S8 and S9 are open. The positive bus BUS+ and negative bus BUS- of the power amplifier module 230 are connected to the output of the second power module 210 through switches S6 and S7. When power is supplied from the capacitor board 100, switches S8 and S9 are closed, and switches S6 and S7 are open. The positive bus BUS+ and negative bus BUS- of the power amplifier module 230 are connected to the positive line CAP_BUS+ and the negative line CAP_BUS- in the power cable through switches S8 and S9.

[0047] By employing an external capacitor board 100 and a bus selection module 220, selection can be made according to different scenarios, and the output specifications of the power supply are achieved by switching the external capacitor board 100. The bus selection module 220 interconnects the capacitor board 100 and the power board 200, technically reducing the design complexity of the power supply. The power board 200 can be used independently of the capacitor board 100, improving the functional compatibility of the power supply. Furthermore, upgrades can be made to either the capacitor board 100 or the power board 200 separately, providing greater convenience for subsequent design upgrades. With external capacitors, power devices can be distributed across different boards without being limited by single-board size, overcoming the energy density limitations of a single board.

[0048] In one embodiment, a testing machine is also provided, including the power supply device described above. The testing machine may further include a host computer, which is connected to a first control signal terminal and a second control signal terminal, and outputs control signals to control the power supply to the power supply device. The host computer may be, but is not limited to, various personal computers, laptops, smartphones, tablets, and portable wearable devices, such as smartwatches, smart bracelets, and head-mounted devices.

[0049] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0050] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A power supply device, characterized in that, include: The capacitor board is connected to the first power supply terminal and is connected to the power supply board via a power cable. The capacitor board stores energy according to the power supply connected to the first power supply terminal, and transmits the stored energy to the power board through the power cable; The power board is connected to the second power terminal, the power cable, and the device under test. The power board selects the power source connected to the second power terminal or the energy transmitted by the power cable to power the device under test.

2. The power supply device according to claim 1, characterized in that, The capacitor board includes a first power module, an energy storage module, and a discharge module. The first power module is connected to the first power supply terminal and the energy storage module. The discharge module is connected to the energy storage module and the power cable. The first power module converts the voltage of the power supplied to the first power supply terminal and then supplies it to the energy storage module. The discharge module supplies the energy stored in the energy storage module to the power board through the power cable.

3. The power supply device according to claim 2, characterized in that, The first power module includes a transformer, a rectifier bridge, a BUCK circuit, and an LDO circuit connected in sequence. The transformer is connected to the first power supply terminal, and the LDO circuit is connected to the energy storage module.

4. The power supply device according to claim 3, characterized in that, The energy storage module includes a capacitor assembly connected to the LDO circuit, which consists of several capacitors connected in series and / or in parallel.

5. The power supply device according to claim 4, characterized in that, The discharge module includes a discharge switch unit and an output switch unit. The discharge switch unit is connected to the capacitor assembly and the output switch unit, and the output switch unit is connected to the power cable. When the discharge switch unit is turned on and the output switch unit is turned off, the energy stored in the capacitor assembly is discharged through the discharge switch unit. When the discharge switch unit is turned off and the output switch unit is turned on, the energy of the energy storage module is transmitted to the power cable through the output switch unit.

6. The power supply device according to claim 5, characterized in that, The transformer, rectifier bridge, BUCK circuit, LDO circuit, capacitor assembly, and discharge switch unit are all in pairs. The transformer, rectifier bridge, BUCK circuit, LDO circuit, capacitor assembly, and discharge switch unit are connected in sequence. The output switch unit is connected to each discharge switch unit and the power cable.

7. The power supply device according to claim 6, characterized in that, One of the discharge switch units includes switch S1 and discharge resistor R1, the other discharge switch unit includes switch S2 and discharge resistor R2, and the output switch unit includes switch S3, switch S4 and switch S5; The first end of switch S1 is connected to one end of the corresponding capacitor assembly and one end of the corresponding LDO circuit. The second end of switch S1 is connected to the first end of discharge resistor R1. The second end of discharge resistor R1 is connected to the other end of the corresponding capacitor assembly and the other end of the corresponding LDO circuit. The first end of switch S2 is connected to one end of the corresponding capacitor assembly, the second end of discharge resistor R1, and one end of the corresponding LDO circuit. The second end of switch S2 is connected to the first end of discharge resistor R2. The second end of discharge resistor R2 is connected to the other end of the corresponding capacitor assembly and the other end of the corresponding LDO circuit. The first end of switch S3 is connected to the first end of switch S1, the second end of switch S3 is connected to the positive wire in the power cable, the first end of switch S4 is connected to the second end of discharge resistor R1 and the first end of switch S2, the second end of switch S4 is connected to the ground wire in the power cable, the first end of switch S5 is connected to the second end of discharge resistor R2, and the second end of switch S5 is connected to the negative wire in the power cable.

8. The power supply device according to claim 2, characterized in that, The capacitor board also includes a first control module, which is connected to a first control signal terminal, the first power supply module, and the discharge module.

9. The power supply device according to claim 8, characterized in that, The first control module includes a logic circuit and a driver. The logic circuit is connected to the first control signal terminal and the driver, and the driver is connected to the first power supply module and the discharge module.

10. The power supply device according to any one of claims 1 to 9, characterized in that, The power board includes a second power module, a bus selection module, and a power amplifier module. The second power module is connected to a second power supply terminal and the bus selection module. The bus selection module is connected to the power cable and the power amplifier module. The power amplifier module is connected to the device under test (DUT). The second power module converts the voltage of the power supplied to the second power supply terminal and then supplies it to the bus selection module. The bus selection module selects whether to use the voltage converted by the second power module or the energy supplied by the power cable, and after adjustment by the power amplifier module, supplies power to the DUT.

11. The power supply device according to claim 10, characterized in that, The bus selection module includes switches S6, S7, S8, and S9. The first end of switch S6 is connected to the positive output of the second power module, and the second end of switch S6 is connected to the positive bus of the power amplifier module. The first end of switch S7 is connected to the negative output of the second power module, and the second end of switch S7 is connected to the negative bus of the power amplifier module. The first end of switch S8 is connected to the positive wire in the power cable, and the second end of switch S8 is connected to the positive bus of the power amplifier module. The first end of switch S9 is connected to the negative wire in the power cable, and the second end of switch S9 is connected to the negative bus of the power amplifier module.

12. The power supply device according to claim 10, characterized in that, The power board also includes a second control module, which is connected to a second control signal terminal, the second power module, the bus selection module, and the power amplifier module.

13. A testing machine, characterized in that, Includes the power supply device according to any one of claims 1 to 12.

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