Circuit jig plate and PCB (printed circuit board)

Abstract

The utility model discloses a circuit jig plate and a PCB, and relates to the technical field of interface signal testing, in a circuit structure of the circuit jig plate, the output end of a voltage source module is electrically connected with the input end of a voltage selection module; the output end of the voltage selection module is electrically connected with the first end of the test resistor; the voltage selection module comprises at least two selection switches; the at least two selection switches are used for converting a target voltage into a selected test voltage value so as to transmit the test voltage value to the first end of the test resistor; the second end of the test resistor is used for connecting a to-be-tested pin. According to the circuit jig plate, the voltage generated by the voltage source module can be converted into various test voltage values through the voltage selection module, and the test voltage value transmitted to the test resistor can be selected through the selection switch in the voltage selection module; therefore, through the circuit jig plate, a complete testing process of the pins needing various testing voltages can be completed, multiple welding is avoided, the accuracy and the convenience of pin testing are improved, and the cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of interface signal testing, and in particular to a circuit fixture board and a PCB board. Background Art

[0002] With the development of high-speed technology, the application of HDMI (High Definition Multimedia Interface) interface is increasing, and the requirements for testing are also increasing. Comprehensive testing can improve product quality and reliability.

[0003] In order to ensure the comprehensive test of the HDMI source interface test, it is necessary to test the HPD (Hot Plug Detect) signal according to the HDMI protocol. The HDMI protocol requires the HPD signal test to be connected to a 1.2KΩ resistor at one end of the HPD pin and a different power supply at the other end of the resistor, and the corresponding high and low level test requirements are met through voltage switching.

[0004] At present, the test equipment is powered by an external ready-made power supply and manually welded with a fixed 1.2KΩ resistor (according to the HDMI protocol). The external power supply is mainly a DC power supply. The voltage switching is achieved by setting the DC power supply, which requires repeated welding. Because each time the voltage is set by the DC power supply, a 1.2KΩ resistor needs to be welded between the DC power supply and the HPD pin. Different voltage values ​​need to be used during the test of the HDP pin, so multiple welding is required, which makes the test less convenient and accurate, and the cost of purchasing power supply equipment that meets the test requirements is high. Utility Model Content

[0005] The present application provides a circuit fixture board and a PCB board, which improve the accuracy and convenience of testing an HDMI source interface and can reduce costs.

[0006] In one aspect, the present application provides a circuit fixture board;

[0007] The circuit structure in the circuit fixture board includes a voltage source module, a voltage selection module, and a test resistor;

[0008] The output end of the voltage source module is electrically connected to the input end of the voltage selection module to provide a target voltage to the voltage selection module;

[0009] The output end of the voltage selection module is electrically connected to the first end of the test resistor; the voltage selection module includes at least two selection switches; the at least two selection switches are used to convert the target voltage into a selected test voltage value to be transmitted to the first end of the test resistor;

[0010] The second end of the test resistor is used to connect to the pin to be tested.

[0011] In a possible implementation, the at least two selection switches include a first switch, a second switch, a third switch, and a fourth switch; the voltage selection module further includes a fourth resistor, a fifth resistor, and a sixth resistor;

[0012] The input end of the voltage selection module is connected to the output end of the voltage selection module through the first switch;

[0013] The input end of the voltage selection module is also connected to the first node through the fourth resistor; the first node is connected to the output end of the voltage selection module through the second switch;

[0014] The first node is also connected to the second node through the fifth resistor; the second node is connected to the output end of the voltage selection module through the third switch;

[0015] The second node is also connected to the first end of the sixth resistor; the second end of the sixth resistor is grounded; the second end of the sixth resistor is also connected to the output end of the voltage selection module through a fourth switch.

[0016] In a possible implementation, the target voltage is 5.3V;

[0017] The fourth resistor is 29KΩ, the fifth resistor is 20KΩ, and the sixth resistor is 4KΩ.

[0018] In a possible implementation manner, the first switch, the second switch, the third switch, and the fourth switch are jumper cap switches.

[0019] In a possible implementation manner, the output end of the voltage selection module is connected to the first end of the test resistor through a voltage follower.

[0020] In a possible implementation, the voltage follower includes an operational amplifier U1 and a seventh resistor R7;

[0021] The output end of the voltage selection module is connected to the non-inverting input end of the operational amplifier; the inverting input end of the operational amplifier is connected to the output end of the operational amplifier U1 through the seventh resistor R7;

[0022] The output terminal of the operational amplifier U1 is connected to the first terminal of the test resistor.

[0023] In a possible implementation, the voltage source module includes a first resistor, a second resistor, a third resistor, and an adjustable shunt regulator;

[0024] The power supply voltage terminal of the circuit fixture board is connected to the output terminal of the voltage source module through the first resistor;

[0025] The output end of the voltage source module is connected to the cathode of the adjustable parallel regulator; the anode of the adjustable parallel regulator is grounded; the output end of the voltage source module is also connected to the reference end of the adjustable parallel regulator through the second resistor; the reference end of the adjustable parallel regulator is grounded through the third resistor.

[0026] In a possible implementation manner, the pin to be tested is an HPD pin of an HDMI interface.

[0027] On the other hand, the present application provides a PCB board, which is used to set a target circuit, and the target circuit is the above-mentioned circuit structure.

[0028] On the other hand, the present application provides a circuit fixture board, which includes the above-mentioned PCB board.

[0029] The technical solution provided by this application may have the following beneficial effects:

[0030] An embodiment of the present application provides a circuit fixture board, comprising a voltage source module, a voltage selection module, and a test resistor in the circuit fixture board; the output end of the voltage source module is electrically connected to the input end of the voltage selection module to provide a target voltage to the voltage selection module; the output end of the voltage selection module is electrically connected to the first end of the test resistor; the voltage selection module includes at least two selection switches; the at least two selection switches are used to convert the target voltage into a selected test voltage value to transmit it to the first end of the test resistor; the second end of the test resistor is used to connect a pin to be tested. That is, the circuit fixture board provided by the above scheme can convert the voltage generated by the voltage source module into a variety of test voltage values ​​through the voltage selection module, and can select the test voltage value transmitted to the test resistor through the selection switch in the voltage selection module. Therefore, the complete test process of pins requiring multiple test voltages can be completed through the circuit fixture board. On the one hand, there is no need for testers to prepare DC power supplies with multiple voltage values ​​and weld test resistors separately, thereby saving the cost of the pin testing process and reducing resource consumption in the pin testing process. On the other hand, a 1.2KΩ resistor has been connected to the circuit fixture board, so multiple welding is not required to implement the pin testing process, which improves the convenience and accuracy of the pin testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 The figure is a schematic diagram of the structure of a circuit fixture board according to an exemplary embodiment.

[0033] Figure 2 A schematic diagram of a specific circuit structure of a circuit fixture board involved in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0034] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0035] In the description of the embodiments of the present application, the term "corresponding" may indicate a direct or indirect correspondence between two items, or an association relationship between the two items, or a relationship between indication and being indicated, configuration and being configured, and the like.

[0036] Figure 1 FIG. 1 is a schematic diagram showing the structure of a circuit fixture board according to an exemplary embodiment. Figure 1 As shown, the circuit structure in the circuit fixture board includes a voltage source module, a voltage selection module, and a test resistor R8;

[0037] The output end of the voltage source module is electrically connected to the input end of the voltage selection module to provide a target voltage to the voltage selection module;

[0038] The output end of the voltage selection module is electrically connected to the first end of the test resistor R8; the voltage selection module includes at least two selection switches; the at least two selection switches are used to convert the target voltage into a selected test voltage value to be transmitted to the first end of the test resistor;

[0039] The second end of the test resistor R8 is used to connect to the pin to be tested.

[0040] During the interface test, the same pin of the same interface may require different test environments for testing. In a possible implementation of the embodiment of the present application, the circuit fixture board is used to test the HPD pin of HDMI. At this time, due to the HPD signal test requirements in HDMI, one end of the HPD PIN foot (pin) needs to be connected to a 1.2KΩ resistor, and the other end of the resistor needs to be connected to a voltage source (5.3V, 2.4V, 0.4V and 0V). If an external voltage source is used to test the HPD signal, the 1.2KΩ resistor needs to be repeatedly welded to multiple different voltage sources. Multiple welding processes not only waste resources and time, but also result in low accuracy of the interface test.

[0041] At this time, if Figure 1 When the circuit fixture board shown is used to test the HPD signal of HDMI, it is only necessary to adaptively set the output capability of the voltage source module and the conversion capability of the voltage selection module (for example, using components of specific specifications in the voltage source module and the voltage selection module). That is, the output voltage of the voltage source module can be selectively converted into the test voltage value required for the HDMI HPD signal test after passing through the voltage selection module (for example, converted to 5.3V, 2.4V, 0.4V and 0V through the four selection switches in the voltage selection module). At this time, the test voltage value is connected to the pin to be tested through the 1.2KΩ test resistor R8, and the complete test process of the HDMI HPD signal can be directly realized through the circuit fixture board.

[0042] Please refer to Figure 2 , which shows a schematic diagram of a specific circuit structure of a circuit fixture board involved in an embodiment of the present application. Figure 2 As shown, at least two selection switches in the voltage selection module include a first switch J1, a second switch J2, a third switch J3 and a fourth switch J4; the voltage selection module also includes a fourth resistor R4, a fifth resistor R5 and a sixth resistor R6;

[0043] The input end of the voltage selection module is connected to the output end of the voltage selection module through the first switch J1;

[0044] The input end of the voltage selection module is also connected to the first node through the fourth resistor R4; the first node is connected to the output end of the voltage selection module through the second switch J2;

[0045] The first node is also connected to the second node through the fifth resistor R5; the second node is connected to the output end of the voltage selection module through the third switch J3;

[0046] The second node is also connected to the first end of the sixth resistor R6; the second end of the sixth resistor R6 is grounded; the second end of the sixth resistor R6 is also connected to the output end of the voltage selection module through a fourth switch J4.

[0047] In a possible implementation of an embodiment of the present application, the voltage output by the voltage source module is 5.3V; at this time, the voltage selection module can convert 5.3V into four test voltage values ​​of 5.3V, 2.4V, 0.4V and 0V by controlling the first switch J1, the second switch J2, the third switch J3 and the fourth switch J4.

[0048] Optionally, at this time, the resistance of the test resistor R8 is 1.2KΩ.

[0049] In a possible implementation of the embodiment of the present application, the voltage at the output end of the voltage source module is 5.3V, and the voltage at the input end of the voltage selection module is also 5.3V; the input end of the voltage selection module is connected to the first node through the fourth resistor R4; the first node is connected to the second node through the fifth resistor R5; the second node is grounded through the sixth resistor R6; at this time, the fourth resistor R4, the fifth resistor R5 and the sixth resistor R6 divide the voltage at the input end of the voltage selection module in turn.

[0050] In a possible implementation of an embodiment of the present application, if the fourth resistor is designed to be 29KΩ, the fifth resistor R5 is designed to be 20KΩ, and the sixth resistor R6 is designed to be 4KΩ, the ground voltage of the second end of the sixth resistor is 0, and at this time the first node voltage should be 2.4V, and the second node voltage should be 0.4V.

[0051] Therefore, if the first switch J1 is closed and the other switches are opened, the first switch J1 directly transmits the voltage 5.3V at the input end of the voltage selection module to the output end of the voltage selection module as the test voltage value;

[0052] If the second switch J2 is closed and the other switches are open, the second switch J2 directly transmits the voltage 2.4V of the first node to the output end of the voltage selection module as the test voltage value;

[0053] If the third switch J3 is closed and the other switches are opened, the third switch J3 directly transmits the voltage 0.4V of the second node to the output end of the voltage selection module as the test voltage value;

[0054] If the fourth switch J4 is closed and the other switches are opened, the fourth switch J4 directly connects the output end of the voltage selection module to the ground, and the test voltage value is 0V at this time.

[0055] In a possible implementation, the first switch J1, the second switch J2, the third switch J3, and the fourth switch J4 are jumper cap switches. In this case, the tester can switch between four voltages (e.g., 5.3V, 2.4V, 0.4V, and 0V) by controlling the connection and removal of each jumper cap switch.

[0056] In a possible implementation, in order to avoid the influence on the current or voltage in the above circuit when the external interface pin is connected to the circuit fixture board through the test resistor R8, the output end of the voltage selection module is connected to the first end of the test resistor through a voltage follower. The input end of the voltage follower is connected to the output end of the voltage selection module; the output end of the voltage follower is connected to the first end of the test resistor, so that the output end voltage of the voltage selection module is directly copied to the first end of the test resistor, and the influence of the external interface pin on the voltage selection module and the voltage source module is disconnected.

[0057] In a possible implementation, the structure of the voltage follower can be as follows: Figure 2 As shown, the voltage follower includes an operational amplifier U1 and a seventh resistor R7; the output end of the voltage selection module is connected to the non-inverting input end of the operational amplifier U1; the inverting input end of the operational amplifier U1 is connected to the output end of the operational amplifier U1 through the seventh resistor R7; the output end of the operational amplifier U1 is connected to the first end of the test resistor.

[0058] Furthermore, the positive power supply terminal of the voltage follower is connected to a 3.3V voltage; the negative power supply terminal of the power follower is grounded; and the resistance value of the seventh resistor is 10KΩ.

[0059] In a possible implementation, the structure of the voltage source module in the embodiment of the present application can be Figure 2 As shown, the voltage source module includes a first resistor R1, a second resistor R2, a third resistor R3 and an adjustable parallel regulator;

[0060] The power supply voltage terminal of the circuit fixture board is connected to the output terminal of the voltage source module through the first resistor R1;

[0061] The output end of the voltage source module is connected to the cathode of the adjustable parallel regulator; the anode of the adjustable parallel regulator is grounded; the output end of the voltage source module is also connected to the reference end of the adjustable parallel regulator through the second resistor R2; the reference end of the adjustable parallel regulator is grounded through the third resistor R3.

[0062] Further, such as Figure 2As shown, the resistance of the first resistor R1 in the voltage source module is 1KΩ; the resistance of the second resistor R2 is 11.2KΩ; the resistance of the third resistor R3 is 10KΩ; and the reference terminal voltage value of the adjustable shunt regulator is 2.5V. Optionally, the model of the adjustable shunt regulator can be TL431.

[0063] In the voltage source module, the 12V voltage is used to power the voltage source module, that is, to power the entire circuit fixture board. Since the reference terminal voltage value of the adjustable shunt regulator is 2.5V, the output terminal voltage of the voltage source module is equal to That is 5.3V.

[0064] It should be noted that the HPD pin of HDMI in the embodiment of the present application is an exemplary application scenario. The circuit fixture board proposed in the present application can also test other pins of other interfaces, that is, according to the voltage value required for the interface test, the parameters of each resistor and the adjustable parallel regulator in the circuit fixture board are adjusted (for example, different specifications are selected), so that various interfaces requiring different test voltages can be tested.

[0065] In the embodiment of the present application, the circuit fixture board also includes a PCB board, and the PCB board of the circuit fixture board is provided with Figure 2 The circuit structure shown can realize the function of testing various interface pins requiring different test voltages.

[0066] In one embodiment, the present application also includes a PCB board, on which a target circuit is arranged. The target circuit is as follows: Figure 2 The circuit structure shown in the figure can realize the function of testing various interface pins requiring different test voltages.

[0067] In summary, the embodiment of the present application provides a circuit fixture board, in which the circuit structure includes a voltage source module, a voltage selection module, and a test resistor; the output end of the voltage source module is electrically connected to the input end of the voltage selection module to provide a target voltage to the voltage selection module; the output end of the voltage selection module is electrically connected to the first end of the test resistor; the voltage selection module includes at least two selection switches; the at least two selection switches are used to convert the target voltage into a selected test voltage value to be transmitted to the first end of the test resistor; the second end of the test resistor is used to connect the pin to be tested. That is, the circuit fixture board provided by the above scheme can convert the voltage generated by the voltage source module into a variety of test voltage values ​​through the voltage selection module, and can select the test voltage value transmitted to the test resistor through the selection switch in the voltage selection module. Therefore, the complete test process of the pins requiring multiple test voltages can be completed through the circuit fixture board, avoiding multiple welding, improving the accuracy and convenience of pin testing, and reducing costs.

[0068] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the utility model disclosed herein. The present application is intended to cover any variations, uses or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0069] It should be understood that the present application is not limited to the exact construction that has been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof.

Claims

1. A circuit fixture board, characterized in that: The circuit structure in the circuit fixture board includes a voltage source module, a voltage selection module, and a test resistor; The output end of the voltage source module is electrically connected to the input end of the voltage selection module to provide a target voltage to the voltage selection module; The output end of the voltage selection module is electrically connected to the first end of the test resistor; the voltage selection module includes at least two selection switches; The at least two selection switches are used to convert the target voltage into a selected test voltage value to be transmitted to the first end of the test resistor; The second end of the test resistor is used to connect to the pin to be tested.

2. The circuit fixture board according to claim 1, characterized in that: The at least two selection switches include a first switch, a second switch, a third switch and a fourth switch; the voltage selection module also includes a fourth resistor, a fifth resistor and a sixth resistor; The input end of the voltage selection module is connected to the output end of the voltage selection module through the first switch; The input end of the voltage selection module is also connected to the first node through the fourth resistor; the first node is connected to the output end of the voltage selection module through the second switch; The first node is also connected to the second node through the fifth resistor; the second node is connected to the output end of the voltage selection module through the third switch; The second node is also connected to the first end of the sixth resistor; the second end of the sixth resistor is grounded; the second end of the sixth resistor is also connected to the output end of the voltage selection module through a fourth switch.

3. The circuit fixture board according to claim 2, characterized in that: The first switch, the second switch, the third switch and the fourth switch are jumper cap switches.

4. The circuit fixture board according to claim 2, characterized in that: The target voltage is 5.3V; The fourth resistor is 29KΩ, the fifth resistor is 20KΩ, and the sixth resistor is 4KΩ.

5. The circuit fixture board according to any one of claims 1 to 4, characterized in that: The output end of the voltage selection module is connected to the first end of the test resistor through a voltage follower.

6. The circuit fixture board according to claim 5, characterized in that: The voltage follower includes an operational amplifier U1 and a seventh resistor R7; The output end of the voltage selection module is connected to the non-inverting input end of the operational amplifier; the inverting input end of the operational amplifier is connected to the output end of the operational amplifier U1 through the seventh resistor R7; The output terminal of the operational amplifier U1 is connected to the first terminal of the test resistor.

7. The circuit fixture board according to any one of claims 1 to 4, characterized in that: The voltage source module includes a first resistor, a second resistor, a third resistor and an adjustable shunt regulator; The power supply voltage terminal of the circuit fixture board is connected to the output terminal of the voltage source module through the first resistor; The output end of the voltage source module is connected to the cathode of the adjustable parallel regulator; the anode of the adjustable parallel regulator is grounded; the output end of the voltage source module is also connected to the reference end of the adjustable parallel regulator through the second resistor; the reference end of the adjustable parallel regulator is grounded through the third resistor.

8. The circuit fixture board according to any one of claims 1 to 4, characterized in that: The pin to be tested is the HPD pin of the HDMI interface.

9. A PCB board, characterized in that: The PCB board is used to set a target circuit, and the target circuit is a circuit structure as described in any one of claims 1 to 8.

10. A circuit fixture board, characterized in that: The circuit fixture board includes the PCB board as claimed in claim 9.

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