DCC signal line anti-interference direct capacitor coupling method test fixture

Abstract

The utility model relates to the technical field of DCC test, and discloses a DCC signal line anti-interference direct capacitor coupling method test fixture, which comprises an input end, a coupling mechanism and an output end which are connected in sequence, the input end comprises a BNC female joint jack, the coupling mechanism comprises an outer box and two CBB capacitors, the output end comprises two coupling pulse output jacks, and the outer box comprises an outer box and two CBB capacitors. The BNC female connector socket is connected with one ends of the two CBB capacitors, the other ends of the two CBB capacitors are respectively connected with the coupling pulse output sockets, and the two CBB capacitors are both arranged in the outer box. According to the utility model, the problem that the existing DCC test lacks a targeted test fixture capable of outputting the same coupling signal at the same time can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of DCC testing, in particular to a test fixture for anti-interference direct capacitor coupling method of DCC signal lines. Background Art

[0002] At present, when the laboratory conducts tests on twisted pairs and balanced symmetrical lines (such as audio bridge line CAN communication lines), the injection pulse coupling test should be carried out on all cables simultaneously. However, the existing technology has no special tooling for the ISO 7637 DCC balanced line differential line test system. During daily testing, two corresponding capacitors need to be welded to the output end of the pulse generator, and the capacitor output end is welded to the balanced line differential wire harness of the test sample for testing. The efficiency is very low, and there are risks such as false soldering and short circuit. Moreover, the capacitors are exposed to the air and are prone to oxidation and aging, which affects the use effect. The human body can easily touch them and generate static electricity, resulting in damage.

[0003] The prior art provides a test fixture for anti-interference of automotive signal lines (publication number CN204649870U), which includes several coupling signal channels, and each coupling signal channel includes an input end and an output end. The utility model couples the interference signal of the signal generator to the object under test by connecting the input end of one of the coupling signal channels to the signal generator and the output end to the object under test. The utility model is convenient to replace and has high efficiency. However, in practice, for the DCC balanced line differential line test that requires simultaneous input of coupling signals to the test sample, it is not universal and cannot output the same coupling signals to the balanced line differential lines of the test sample simultaneously, resulting in a lack of targeted test fixture for such tests and affecting the experimental effect. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a test fixture for anti-interference direct capacitor coupling method of DCC signal lines to solve the problem that the existing DCC balanced line differential line test system lacks a test fixture capable of simultaneously outputting coupling signals.

[0005] To achieve the above purpose, the utility model adopts the following technical scheme: A test fixture for anti-interference direct capacitor coupling method of DCC signal lines includes an input end, a coupling mechanism, and an output end connected in sequence. The input end includes a BNC female connector socket. The coupling mechanism includes an outer box and two CBB capacitors. The output end includes two coupling pulse output connector sockets. The BNC female connector socket is connected to one end of the two CBB capacitors, and the other ends of the two CBB capacitors are respectively connected to a coupling pulse output connector socket. Both CBB capacitors are arranged inside the outer box.

[0006] The principle of this solution is:

[0007] In actual application, the pulse generator, the present utility model, and the sample to be tested are connected in sequence. The pulse generator generates high-frequency fast and slow pulse signals, which are injected into the DCC signal line anti-interference direct capacitor coupling method test fixture through the pulse injection line. After being coupled by the internal CBB capacitor, the coupled pulse signal is injected into the differential line of the sample to be tested through the output end, completing the ISO 7637-3, DCC balanced line differential line test.

[0008] The advantages of this solution are as follows:

[0009] 1. The internal part of the device of the present utility model is designed in two paths, injecting coupling signals into the differential line to be tested simultaneously, meeting the requirements of DCC balanced line differential line testing. It can perform DCC method fast pulse and slow pulse tests on samples to be tested with structures such as twisted pairs and balanced symmetrical lines (such as audio bridge line CAN communication lines), enabling rapid replacement, being highly efficient, and having universality for different products to be measured.

[0010] 2. In the traditional technology, the capacitor is exposed and can be directly touched, easily causing short circuits and damaging the pulse generator, and static electricity of the human body can easily damage the capacitor. In the present utility model, the capacitor is arranged inside the outer box, which can effectively avoid accidental touch and damage to the capacitor.

[0011] Preferably, as an improvement, the CBB capacitor is a 600V high-voltage non-polar CBB capacitor. Since when using a 24V system for testing, the maximum pulse voltage is 200V, considering the prevention of capacitor damage, compatibility during use, and safety, the selected withstand voltage value of the capacitor is generally 3 times the maximum pulse voltage. Therefore, a 600V high-voltage non-polar CBB capacitor is selected in this solution.

[0012] Preferably, as an improvement, the BNC female connector socket is arranged on one side of the outer box. Arranging the BNC female connector socket on one side of the outer box is beneficial for testers to plug and unplug coaxial cables, which is conducive to testing efficiency.

[0013] Preferably, as an improvement, the two coupled pulse output connector sockets are arranged on the side of the outer box opposite to the BNC female connector socket. The two coupled pulse output connector sockets simultaneously output the high-frequency pulses coupled by the capacitor to the differential lines of the twisted-pair sample to be tested respectively, meeting the requirements of DCC balanced line differential line testing. At the same time, integrating the two coupled pulse output connector sockets on the side of the outer box opposite to the BNC female connector socket is beneficial for internal cable layout, and at the same time, it is convenient for testers to place this test fixture and plug and unplug the output line, which is conducive to the progress of the test.

[0014] Preferably, as an improvement, the input end further includes a TNC female socket, and the TNC female socket is arranged on the same side of the outer box as the BNC female socket. There are two types of connectors for the output cables of existing pulse generator devices on the market (BNC male, TNC male). For different pulse injection interfaces, two different connectors (BNC female, TNC female) are integrated at the input end of the present utility model to match different pulse generator devices, so as to reduce the test time; at the same time, the two jacks are arranged on the same side, which can save the dressing time of the tester.

[0015] Preferably, as an improvement, the outer box is a metal sealed box. The metal sealed box has good overall sealing performance, is not easy to contact oxidation, the solder joints are firm and reliable, and it cannot be directly contacted, which can effectively protect the capacitor, improve the service life, and at the same time reduce the safety hazard caused by short circuit.

[0016] Preferably, as an improvement, it further includes a grounding post, and the grounding post is arranged on the same side of the outer box as the BNC female socket. The grounding post is used for grounding to avoid electric shock caused by the leakage of the metal outer box. Description of the Drawings

[0017] Figure 1 It is the front view of Embodiment 1 of the present utility model;

[0018] Figure 2 It is the structural schematic diagram of Embodiment 1 of the present utility model;

[0019] Figure 3 It is the structural schematic diagram of Embodiment 2 of the present utility model;

[0020] Figure 4 It is the front view of Embodiment 2 of the present utility model;

[0021] Figure 5 It is the circuit diagram of Embodiment 2 of the present utility model. Detailed Embodiments

[0022] The following is further detailed through specific embodiments:

[0023] The reference numerals in the drawings of the specification include: pulse generator 1, pulse injection line 2, ground wire 3, BNC female socket 4, TNC female socket 5, grounding post 6, outer box 7, 600V high-voltage non-polar CBB capacitor 8, coupled pulse output socket 9, coupled pulse differential line balanced line output line 10, sample under test 11, differential line I 12, differential line II 13.

[0024] Embodiment 1

[0025] Embodiment 1 is basically as shown in the attached Figure 1 、 2 figures:

[0026] A DCC signal line anti-interference direct capacitor coupling method test fixture, comprising an input end, a coupling mechanism, and an output end connected in sequence. The input end includes a BNC female connector socket 4 for connecting a pulse generator 1 with a BNC male connector as the output cable connector. The coupling mechanism includes an outer box 7 and two 600V high-voltage non-polar CBB capacitors. The output end includes two coupling pulse output connector sockets 9 for connecting the twisted differential line I 12 and differential line II 13 of the device under test 11. One end of the BNC female connector socket 4 is connected to the two 600V high-voltage non-polar CBB capacitors, and the other ends of the two 600V high-voltage non-polar CBB capacitors are respectively connected to a coupling pulse output connector socket 9. The two 600V high-voltage non-polar CBB capacitors are fixedly arranged inside the outer box 7, the BNC female connector socket 4 is arranged outside the outer box 7, and the two coupling pulse output connector sockets 9 are arranged on the side of the outer box 7 opposite to the BNC female connector socket 4, which is conducive to the tester inserting and removing the BNC female connector socket 4 and the coupling pulse output connector socket 9. At the same time, the BNC female connector socket 4 and the coupling pulse output connector socket 9 are arranged opposite to each other, which is conducive to the cable routing. The outer box 7 is a metal sealed box formed by welding to prevent the capacitor from directly contacting the air and causing oxidation, or the tester from accidentally touching and causing a short circuit. To ensure the safety of the metal sealed box, this embodiment further includes a grounding post 6. The grounding post 6 is arranged on the same side of the outer box 7 as the BNC female connector socket 4 and is located below the BNC female connector socket 4. The grounding post 6 is connected to the BNC female connector socket 4 through a wire. Insulation protection measures are provided for the BNC female connector socket 4 and the two coupling pulse output connector sockets 9.

[0027] During specific use, connect the pulse generator 1 and the BNC female connector socket 4, and use two coupling pulse differential line balanced line output lines 10 to connect the two coupling pulse output connector sockets 9 with the twisted differential line I 12 and differential line II 13 of the device under test 11 respectively. Turn on the pulse generator 1 to generate high-frequency fast / slow pulse signals. The signals are injected into this test fixture through the pulse injection line 2. After being coupled by the two 600V high-voltage non-polar CBB capacitors 8 inside, they are output to the twisted differential line I 12 and differential line II 13 of the device under test 11 through the coupling pulse differential line balanced line output lines 10 connected to the two coupling pulse output connector sockets 9, completing the ISO 7637 DCC balanced line differential line test.

[0028] Embodiment 2

[0029] Embodiment 2 is basically as shown in Figure 3 、 4 Figure 5:

[0030] The difference between Embodiment 2 and Embodiment 1 is that: in this embodiment, the input end further includes a TNC female jack 5 for connecting a pulse generator 1 with a TNC male connector at the output cable joint. The TNC female jack 5 is connected to two 600V high-voltage non-polar CBB capacitors. The TNC female jack 5 is arranged on the same side as the BNC female jack 4 of the outer box 7 to adapt to pulse generators with TNC male connectors in the market. The TNC female jack 5 is provided with insulation protection measures.

[0031] During specific use, testers can use a pulse generator 1 with a TNC connector at the output cable joint to connect to the TNC female jack 5 to generate high-frequency fast / slow pulses for the above test process. This embodiment can be adapted to two common pulse generator devices in the market to improve the versatility of the test system.

[0032] The above are only embodiments of the present utility model. Specific technical solutions and / or common knowledge such as characteristics well known in the art are not described in detail herein. It should be noted that for those skilled in the art, without departing from the technical solution of the present invention, several deformations and improvements can still be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicability of the patent. The protection scope required by this application should be based on the content of its claims, and the specific implementation manners described in the specification can be used to interpret the content of the claims.

Claims

1. A DCC signal line anti-interference direct capacitor coupling method test fixture, comprising an input end, a coupling mechanism, and an output end connected in sequence, characterized in that: The input end includes a BNC female connector, the coupling mechanism includes an outer box and two CBB capacitors, the output end includes two coupled pulse output connectors, the BNC female connector is connected to one end of the two CBB capacitors, the other ends of the two CBB capacitors are respectively connected to a coupled pulse output connector, and the two CBB capacitors are both arranged inside the outer box.

2. The DCC signal line anti-interference direct capacitor coupling method test fixture according to claim 1, characterized in that: The CBB capacitor is a 600V high voltage non-polar CBB capacitor.

3. The DCC signal line anti-interference direct capacitor coupling method test fixture according to claim 2, characterized in that: The BNC female connector is arranged on one side of the outer box.

4. The DCC signal line anti-interference direct capacitor coupling method test fixture according to claim 3, characterized in that: The two coupling pulse output sockets are arranged on the side of the outer box opposite to the BNC female socket.

5. The DCC signal line anti-interference direct capacitor coupling method test fixture according to claim 4, characterized in that: The input end also includes a TNC female connector, which is connected to two CBB capacitors and is arranged on the same side of the outer box as the BNC female connector.

6. The DCC signal line anti-interference direct capacitor coupling method test fixture according to claim 5, characterized in that: The outer box is a metal sealed box.

7. The DCC signal line anti-interference direct capacitor coupling method test fixture according to claim 6, characterized in that: It also includes a grounding post, which is arranged on the same side of the outer box and the BNC female connector.

Images