HDMI interface power supply circuit on computer mainboard

Abstract

The utility model relates to an HDMI interface power supply circuit on a computer mainboard. The HDMI interface power supply circuit on the computer mainboard comprises an HDMI interface and an NMOSFET, wherein the HDMI interface is arranged on the mainboard and used for being electrically connected with a display screen; a grid electrode of the NMOSFET is electrically connected with a 12V power supply on the mainboard, a source electrode of the NMOSFET is electrically connected with a 5V power supply on the mainboard, and a drain electrode of the NMOSFET is electrically connected with a + 5V power supply pin of the HDMI interface. The HDMI interface power supply circuit on the computer mainboard can prevent a power supply on an HDMI display screen from leaking to a host end of an electronic computer through an HDMI cable.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic computers, in particular to a power supply circuit for an HDMI interface on a computer motherboard. Background Art

[0002] The High-Definition Multimedia Interface (HDMI) is a fully digital video and audio transmission interface that can transmit uncompressed audio and video signals. HDMI can be used in devices such as set-top boxes, DVD players, personal computers, televisions, game consoles, integrated amplifiers, digital audio systems, and televisions. HDMI can transmit audio and video signals simultaneously. Since the audio and video signals use the same cable, it greatly simplifies the installation difficulty of the system wiring.

[0003] The HDMI interface includes multiple pins, such as data signal pins, clock signal pins, +5V power supply pins, etc. When the HDMI transmitting device and the HDMI receiving device connected through the HDMI interface work, for example, an electronic computer host and a display screen, the +5V power supply pin of the HDMI interface needs to maintain normal power supply.

[0004] Recently, display screens using the HDMI interface have developed rapidly. However, due to different perspectives on problems, each display screen manufacturer may only consider the protection of the display screen itself when manufacturing the display screen, but ignore the protection of the computer motherboard or the host. Most of the time, when the user shuts down the electronic computer host, they only turn off the power of the host, so that the power on the host runs out, but they are usually too lazy to unplug the power of the display screen. So at this time, the display screen will be charged while the host is not. If the current on the display screen is too large, or sudden situations such as static electricity occur, it is very likely that the current at the display screen end will flow to the electronic computer host through the HDMI connection cable and damage the host. In this case, the computer motherboard or the host manufacturer needs to propose a solution to avoid this situation. Summary of the Invention

[0005] Therefore, the purpose of the utility model is to provide a power supply circuit for an HDMI interface on a computer motherboard to prevent the power on the HDMI display screen from leaking to the electronic computer host through the HDMI cable.

[0006] To achieve the above object, the present utility model provides a power supply circuit for an HDMI interface on a computer motherboard, comprising: an HDMI interface disposed on the motherboard for electrically connecting a display screen, and an NMOSFET; the gate of the NMOSFET is electrically connected to the 12V power supply on the motherboard, the source is electrically connected to the 5V power supply on the motherboard, and the drain is electrically connected to the +5V power supply pin of the HDMI interface.

[0007] Wherein, the NMOSFET is L2N7002WT1G.

[0008] Wherein, it further includes a fuse; one end of the fuse is electrically connected to the drain of the NMOSFET, and the other end is electrically connected to the +5V power supply pin of the HDMI interface.

[0009] Wherein, the fuse is FB0805.

[0010] Wherein, it further includes an ESD device; one end of the ESD device is electrically connected to the +5V power supply pin of the HDMI interface, and the other end is grounded.

[0011] Wherein, the ESD device is SEP0511P6.

[0012] Wherein, it further includes three filter capacitors; the three filter capacitors are connected in parallel between the +5V power supply pin of the HDMI interface and the ground.

[0013] Wherein, the capacitance values of the three filter capacitors are 4.7 microfarads, 1 microfarad, and 0.1 microfarad respectively.

[0014] Wherein, it further includes a resistor; one end of the resistor is electrically connected to the gate of the NMOSFET, and the other end is electrically connected to the 12V power supply on the motherboard.

[0015] Wherein, the resistance value of the resistor is 4.7 kiloohms.

[0016] In summary, the power supply circuit for the HDMI interface on the computer motherboard of the present utility model can prevent the power on the HDMI display screen from leaking to the electronic computer host through the HDMI cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The following, in conjunction with the drawings, through a detailed description of the specific embodiments of the present utility model, the technical solutions and other beneficial effects of the present utility model will be obvious. In the drawings,

[0018] Figure 1 is the circuit diagram of a preferred embodiment of the power supply circuit for the HDMI interface on the computer motherboard of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] See Figure 1, which is the circuit diagram of a preferred embodiment of the power supply circuit for the HDMI interface on the computer motherboard of the present utility model. The power supply circuit for the HDMI interface on the computer motherboard of the present utility model mainly includes: an HDMI interface disposed on the motherboard for electrically connecting to a display screen, and an NMOSFET PQ2; the gate of the NMOSFET PQ2 is electrically connected to the 12V power supply P12V on the motherboard, the source is electrically connected to the 5V power supply P5V on the motherboard, and the drain is electrically connected to the +5V power supply pin HDMI_P5V of the HDMI interface. In this specific implementation manner, the description mainly focuses on the concept of this application. The other pins of the HDMI interface can be arranged on the motherboard in the common manner in the prior art, which will not be elaborated here.

[0020] In the prior art, when the computer is shut down but the screen power is not turned off, if the current on the HDMI display screen is too large, or sudden situations such as static electricity occur, it is very likely that the current will flow to the host through the HDMI cable and damage the host. The present utility model adds a protection device on the motherboard of the electronic computer host to prevent this situation from occurring.

[0021] In this preferred embodiment, the NMOSFET PQ2 is L2N7002WT1G. It also includes a resistor R2886; one end of the resistor R2886 is electrically connected to the gate of the NMOSFET PQ2, and the other end is electrically connected to the 12V power supply P12V on the motherboard. The resistance value of the resistor R2886 is 4.7 kΩ.

[0022] In this preferred embodiment, it also includes a fuse (FUSE) F1; one end of the fuse F1 is electrically connected to the drain of the NMOSFET PQ2, and the other end is electrically connected to the +5V power supply pin HDMI_P5V of the HDMI interface. The fuse F1 is FB0805.

[0023] In this preferred embodiment, it also includes an ESD device ESD1; one end of the ESD device ESD1 is electrically connected to the +5V power supply pin HDMI_P5V of the HDMI interface, and the other end is grounded. The ESD device ESD1 is SEP0511P6.

[0024] In this preferred embodiment, it also includes three filter capacitors C758 & C759 & C760; the three filter capacitors C758 & C759 & C760 are connected in parallel between the +5V power supply pin HDMI_P5V of the HDMI interface and the ground. The capacitance values of the three filter capacitors HDMI_P5V are 4.7 μF, 1 μF, and 0.1 μF respectively.

[0025] The utility model optimizes the power supply circuit of the HDMI interface, and adds isolation devices, ESD, and FUSE to prevent the power supply on the HDMI display screen from leaking to the host through the HDMI cable, affecting the power supply timing of the host or burning out the host.

[0026] In this preferred embodiment, the utility model adds PQ2 (L2N7002WT1G), whose gate is controlled by the 12V power supply output from the ATX on the host motherboard to control the switch. When the host is not powered on, there is no 12V power supply, so PQ2 is not conducting, preventing the current on the HDMI from flowing to the host and playing an isolation role; when the motherboard is powered on with 12V, PQ2 conducts, supplying 5V power on the motherboard to the HDMI display screen to enable the display screen to work properly. Then, by further adding FUSE, ESD devices, and three filter capacitors, the motherboard is protected from damage caused by the surge current that may be generated on the HDMI.

[0027] In summary, the power supply circuit of the HDMI interface on the computer motherboard of the utility model can prevent the power supply on the HDMI display screen from leaking to the host of the electronic computer through the HDMI cable.

[0028] As described above, for those of ordinary skill in the art, various corresponding changes and deformations can be made according to the technical solution and technical concept of the utility model, and all such changes and deformations should fall within the protection scope of the appended claims of the utility model.

Claims

1. An HDMI interface power supply circuit on a computer motherboard, characterized in that, Including: An HDMI interface provided on the main board for electrically connecting a display screen, and an NMOSFET; The gate of the NMOSFET is electrically connected to the 12V power supply on the main board, the source is electrically connected to the 5V power supply on the main board, and the drain is electrically connected to the +5V power supply pin of the HDMI interface.

2. The HDMI interface power supply circuit on the computer motherboard according to claim 1, characterized in that The NMOSFET is L2N7002WT1G.

3. The HDMI interface power supply circuit on the computer motherboard according to claim 1, wherein It further includes a fuse; one end of the fuse is electrically connected to the drain of the NMOSFET, and the other end is electrically connected to the +5V power supply pin of the HDMI interface.

4. The HDMI interface power supply circuit on the computer motherboard according to claim 3, characterized in that, The fuse is FB0805.

5. The HDMI interface power supply circuit on the computer motherboard according to claim 1, wherein It further includes an ESD device; one end of the ESD device is electrically connected to the +5V power supply pin of the HDMI interface, and the other end is grounded.

6. The HDMI interface power supply circuit on the computer motherboard according to claim 5, characterized in that, The ESD device is SEP0511P6.

7. The HDMI interface power supply circuit on the computer motherboard according to claim 1, characterized in that It further includes three filter capacitors; the three filter capacitors are connected in parallel between the +5V power supply pin of the HDMI interface and the ground.

8. The HDMI interface power supply circuit on the computer motherboard according to claim 7, wherein, The capacitance values of the three filter capacitors are 4.7 microfarads, 1 microfarad and 0.1 microfarad respectively.

9. The HDMI interface power supply circuit on the computer motherboard according to claim 2, wherein It further includes a resistor; one end of the resistor is electrically connected to the gate of the NMOSFET, and the other end is electrically connected to the 12V power supply on the main board.

10. The HDMI interface power supply circuit on the computer motherboard according to claim 9, characterized in that, The resistance value of the resistor is 4.7 kiloohms.

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