HDMI interface test fixture
By designing an HDMI interface test fixture, the problem of traditional testing requiring disassembly was solved, enabling fast and stable signal testing even with the device encased, thus improving the convenience and accuracy of testing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NANJING SIETIUM SEMICON CO LTD
- Filing Date
- 2025-07-10
- Publication Date
- 2026-07-03
AI Technical Summary
Traditional HDMI interface testing requires disassembling the casing for measurement, which is inconvenient and cannot meet the requirements for stability and accuracy. It also cannot measure short circuits or open circuits between pins.
Design an HDMI interface test fixture, including a male clamp, a female recess, signal differential lines, and small signal lines, and set test points to achieve rapid testing of signal quality, connectivity, and power capability without disassembling the device casing.
It enables rapid and stable testing of HDMI interface signal quality and connectivity while the device is encased, reducing operational complexity and cost.
Smart Images
Figure CN224456831U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electronic testing equipment technology, and in particular to an HDMI interface testing fixture. Background Technology
[0002] HDMI, short for High-Definition Multimedia Interface, is a widely used digital audio and video interface standard for electronic devices, supporting the simultaneous transmission of high-definition video and multi-channel audio signals. Due to the high precision requirements of its applications, HDMI interfaces need to be tested periodically to ensure they meet user needs.
[0003] Traditional HDMI interface test pins are typically located on the printed circuit board (PCB) inside the product. Once the product is encased, a malfunction requires disassembly for measurement. Even after disassembly, the small pin spacing and tight arrangement of the HDMI connector can hinder measurement. Furthermore, without HDMI interface test fixtures, the unpredictable position of the measurement probes or sensors leads to unstable and inaccurate signal measurements. Moreover, traditional HDMI testing methods cannot measure short circuits or open circuits between pins. Utility Model Content
[0004] This application provides an HDMI interface test fixture, which solves the problem in the prior art that the product needs to be disassembled and the pin measurement is inconvenient during the measurement of HDMI interfaces. It realizes the technical effect of quickly testing HDMI signals while the product is encased, ensuring the quality stability and connectivity of the signal during the test.
[0005] To achieve the above objectives, this application provides the following technical solution:
[0006] An HDMI interface test fixture includes a printed circuit board (PCB) and further includes: a connector module comprising a male connector and a female connector; one end of the male connector is connected to an HDMI interface, and the other end is connected to the PCB; one end of the female connector is connected to a test instrument, and the other end is connected to the end of the PCB away from the male connector; a signal test module including multiple differential signal lines and multiple small signal lines disposed on the PCB; test points are provided on each of the differential signal lines and the small signal lines; a power supply test module including a power line disposed on the PCB; and two test points are provided on the power line; and a ground wire disposed on the PCB, and test points are provided on the ground wire.
[0007] In conjunction with the first aspect, in one possible implementation, the signal differential lines are four.
[0008] In conjunction with the first aspect, in the second possible implementation, the impedance of the signal differential line is 100Ω, and a test point is provided at the end of each of the signal differential lines.
[0009] In conjunction with the first aspect, in the third possible implementation, the small signal line includes a hot-plug detection signal line, a data channel signal line, and a consumer electronics control line; the small signal line is used to connect to the internal line of the HDMI interface; each of the small signal lines is provided with a test point, and the test point of each small signal line is a through-hole pad structure.
[0010] In conjunction with the first aspect, in a fourth possible implementation, the power supply test module further includes a pin and a shorting cap; the bottom end of the pin is connected to the printed circuit board, and the top end of the pin is connected to the shorting cap.
[0011] In conjunction with the fourth possible implementation of the first aspect, in the fifth possible implementation, the power supply test module receives a 5V power supply; the two test points of the power line are connected by the pins and the shorting cap to achieve on / off control.
[0012] In conjunction with the first aspect, in the sixth possible implementation, the test point of the ground wire is centrally located on the ground wire, and the test point of the ground wire is a through-hole pad structure.
[0013] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:
[0014] This application embodiment utilizes a male connector with a clamp and a female connector to directly connect the HDMI interface and testing instruments. Combined with test points on the differential and small signal lines, it enables rapid testing of the HDMI interface's signal quality, connectivity, and power capability during signal transmission without disassembling the device casing. It offers advantages such as strong compatibility, ease of operation, and low cost. Attached Figure Description
[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0016] Figure 1 This is a structural diagram of an HDMI interface test fixture provided in an embodiment of this application.
[0017] Figure label: 1-Printed circuit board; 2-Male clamp; 3-Female countersunk plate; 4-Test point. Detailed Implementation
[0018] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.
[0019] HDMI (High Definition Multimedia Interface) uses TMDS (Time Minimized Differential Signaling). TMDS is a differential signaling mechanism that uses the voltage difference between two pins to transmit signals. Each standard HDMI connection includes three TMDS channels for data transmission and one independent TMDS clock channel to ensure consistent timing during transmission. Within one clock cycle, each TMDS channel can transmit a 10-bit data stream. This 10-bit data can be composed of several different encoding formats.
[0020] This application provides an HDMI interface test fixture, including a printed circuit board 1 (PCB), a connector module, a signal test module, a power test module, and a ground wire.
[0021] like Figure 1 As shown, the connector module includes a male clamp 2 and a female recess 3. One end of the male clamp 2 is connected to the HDMI interface, and the other end of the male clamp 2 is fixedly connected to the printed circuit board 1.
[0022] One end of the female connector 3 is connected to the testing instrument, and the other end is connected to the end of the printed circuit board 1 away from the male connector 2.
[0023] The signal test module includes multiple signal differential lines and multiple small signal lines. The signal differential lines and small signal lines are all set on the printed circuit board 1. At the same time, each signal differential line and each small signal line has a test point 4 set at any position.
[0024] The power supply test module includes a power cord, which is mounted on the printed circuit board 1. The power cord is broken in the middle, and two test points 4 are set at the break point.
[0025] The ground wire is set on the printed circuit board 1, and a test point 4 is also set on the ground wire.
[0026] This application discloses an HDMI interface testing fixture. The fixture directly connects to the HDMI interface via a male clamp 2 and a female recess 3. Combined with test points 4 on the differential and small signal lines, it enables rapid testing of the HDMI interface's signal quality, connectivity, and power capability during signal transmission without disassembling the device casing. It offers advantages such as strong compatibility, ease of operation, and low cost. This HDMI interface testing fixture is suitable for the R&D and debugging phases of HDMI interfaces, as well as for troubleshooting HDMI interface problems.
[0027] Specifically, the male connector 2 is connected to the signal transmitting end (Source) of the HDMI interface, and the female connector 3 is connected to the signal receiving end (Sink). In this embodiment, the signal receiving end is connected to the testing instrument.
[0028] Taking a desktop computer as an example, the signal sending end is the host, and the signal receiving end is the monitor.
[0029] In this embodiment of the application, there are 4 signal differential lines with an impedance of 100Ω, and each signal differential line has a test point 4 at its end.
[0030] Meanwhile, the small signal lines include hot plug detection signal lines (HPD, Hot Plug Detection), data channel signal lines (DDC, Display Data Channel), and consumer electronic control lines (CEC, Consumer Electronic Control). Each small signal line is equipped with a test point 4, and these test points 4 are attached to the printed circuit board 1 in the form of through-hole pads.
[0031] The hot-plug detection signal line is used to establish a communication connection between the female connector 3 and the male connector 2. The data channel signal line is based on the I2C protocol for transmission. Consumer electronics control is a feature of HDMI that allows users to command and control HDMI-connected devices using only a remote control.
[0032] The power test module also includes pins and shorting caps. The bottom of the pins is connected to the printed circuit board 1, and the top of the pins is connected to the shorting caps.
[0033] Specifically, after the power cord is broken in the middle, a test point 4 is set at each of the two break points. The bottom of the pin is connected to these two test points 4 respectively to reconnect the broken power cord. The top of the pin is connected to a shorting cap, which is used to protect the entire circuit from short circuits. Therefore, the shorting cap needs to be connected to the pin.
[0034] In the power supply test module, the input power supply voltage is 5V. Figure 1 (+5V and +5M). When it is necessary to test the output current capability, disconnect the pin from the printed circuit board 1 and use an electronic load tester or other instruments to measure the current supply capability at one end of the male connector 2 of the clamp.
[0035] In this embodiment, the test point 4 on the ground wire is centrally located at the top of the ground wire, and the test point 4 on the ground wire is also attached to the printed circuit board 1 in the form of a through-hole pad structure.
[0036] In this application example, the HDMI interface test fixture described in this application is used to test the product under test. Specifically, the test procedure is as follows:
[0037] Connect the HDMI interface test fixture to the HDMI female connector of the product under test.
[0038] With the product under test not powered on, use a multimeter to test the signal pins on the HDMI interface test fixture. Specifically, test through multiple test points 4, targeting either the TMDS or DDC signal. The purpose of the test is to check the connectivity of the HDMI interface, i.e., whether the HDMI female connector has a cold solder joint. If the HDMI female connector has a cold solder joint, the multimeter will not beep when testing the corresponding test point 4 on the HDMI interface test fixture using the short circuit setting of the multimeter.
[0039] With the product under test powered on, use a multimeter in voltage mode or an oscilloscope to test the corresponding test point 4 on the HDMI interface test fixture, such as the TMDS signal or DDC signal, to test whether the voltage or frequency of these signals reaches the expected value under normal working conditions.
[0040] The above tests can be performed whether the product under test has an assembled casing or not.
[0041] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.
[0042] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of this application.
Claims
1. An HDMI interface test fixture comprising a printed circuit board (1), characterized in that, Also includes: The connector module includes a male clamp (2) and a female recess (3); one end of the male clamp (2) is used to connect to an HDMI interface, and the other end is connected to the printed circuit board (1); one end of the female recess (3) is connected to a testing instrument, and the other end is connected to the end of the printed circuit board (1) away from the male clamp (2); The signal testing module includes multiple signal differential lines and multiple small signal lines disposed on the printed circuit board (1); test points (4) are disposed on both the signal differential lines and the small signal lines. The power supply test module includes a power line disposed on the printed circuit board (1); and two test points (4) are disposed on the power line; Ground wire, which is provided on the printed circuit board (1), and test points (4) are provided on the ground wire.
2. The HDMI interface test fixture according to claim 1, characterized in that, There are 4 signal differential lines.
3. The HDMI interface test fixture according to claim 1, characterized in that, The impedance of the signal differential line is 100Ω, and a test point (4) is provided at the end of each signal differential line.
4. The HDMI interface test fixture according to claim 1, characterized in that, The small signal line includes a hot-plug detection signal line, a data channel signal line, and a consumer electronics control line; the small signal line is used to connect to the internal cable of the HDMI interface. Each of the small signal lines is provided with a test point (4), and the test point (4) of each small signal line is a through-hole pad structure.
5. The HDMI interface test fixture according to claim 1, characterized in that, The power supply test module also includes pins and shorting caps; The bottom end of the pin is connected to the printed circuit board (1), and the top end of the pin is connected to the shorting cap.
6. The HDMI interface test fixture according to claim 5, characterized in that, The power supply test module is input with a 5V power supply. The two test points (4) of the power line are connected and disconnected via the pins and the shorting cap.
7. The HDMI interface test fixture according to claim 1, characterized in that, The test point (4) of the ground wire is centrally located on the ground wire, and the test point (4) of the ground wire is a through-hole pad structure.