CN217470122U

CN217470122U - HDMI display switching module and electronic equipment

Info

Publication number: CN217470122U
Application number: CN202220348534.3U
Authority: CN
Inventors: 肖倩; 孙君
Original assignee: Hongfujin Precision Industry Wuhan Co Ltd; Hon Hai Precision Industry Co Ltd
Current assignee: Hongfujin Precision Industry Wuhan Co Ltd; Hon Hai Precision Industry Co Ltd
Priority date: 2022-02-21
Filing date: 2022-02-21
Publication date: 2022-09-20
Anticipated expiration: 2032-02-21

Abstract

An HDMI display switching module comprises a mainboard, an HDMI connector, a first detection circuit and a second detection circuit. The mainboard comprises a data processing chip, an independent display card unit and an integrated display card unit. The first detection circuit is electrically connected with an HPD pin and a data processing chip of the HDMI connector, the first detection circuit can enable the data processing chip to read display equipment identification data of the display based on the level of the HPD pin, the second detection circuit can enable the independent display card unit based on the level of the HPD pin, and the data processing chip controls the independent display card unit or the integrated display card unit to send an HDMI signal to the display based on the display equipment identification data. The embodiment of the application also provides the electronic equipment. The HDMI display switching module and the electronic equipment switch the display functions of the independent display card and the integrated display card based on the display parameters of the connected display, and realize the support of HDMI display of various versions.

Description

HDMI display switching module and electronic equipment

Technical Field

The present disclosure relates to a High Definition Multimedia Interface (HDMI) technology, and more particularly, to an HDMI display switching module and an electronic device including the same.

Background

HDMI is a fully digital video and audio transmission interface that can transmit uncompressed audio and video signals. The HDMI can not only meet the resolution of 1080P, but also support digital audio formats such as DVD audio and the like, support eight-channel 96kHz or stereo 192kHz digital audio transmission, and transmit uncompressed audio signals and video signals.

Common versions of the existing HDMI interface include HDMI 1.4, HDMI 2.0, and HDMI 2.1. Most of the integrated display cards of the main board only support the HDMI 1.4 and HDMI 2.0 versions (4K resolutions), and for supporting higher display pixels (such as 8K resolutions/10K resolutions), the main board needs to support the HDMI 2.1 version in combination with an independent display card. How to make the display function of the motherboard compatible with HDMI 2.1 and downward compatible with HDMI 2.0/1.4 becomes a big problem to be solved urgently.

SUMMERY OF THE UTILITY MODEL

In view of the above, it is necessary to provide an HDMI display switching module, which can switch the display functions of an independent display card and an integrated display card to support HDMI display of multiple versions.

An embodiment of the application provides a HDMI shows switching module, including mainboard and the HDMI connector of being connected with the mainboard electricity, the HDMI connector includes that Hot Plug detects (Hot Plug Detect, HPD) pin, and the mainboard includes data processing chip, independent display card unit and integrated display card unit. The HDMI display switching module further comprises a first detection circuit and a second detection circuit, the first detection circuit is electrically connected to the HPD pin and the data processing chip, when the HDMI connector is electrically connected with the display, the first detection circuit enables the data processing chip to read the display device identification data of the display based on the level of the HPD pin, the second detection circuit is electrically connected to the HPD pin and the independent display card unit, the second detection circuit enables the independent display card unit based on the level of the HPD pin, and the data processing chip controls the independent display card unit or the integrated display card unit to send an HDMI signal to the display based on the display device identification data.

In some embodiments, when the display device identification data corresponds to the HDMI 1.4 standard or the HDMI 2.0 standard, the data processing chip controls the integrated graphics card unit to send the HDMI signal to the display, and when the display device identification data corresponds to the HDMI 2.1 standard, the data processing chip controls the independent graphics card unit to send the HDMI signal to the display.

In some embodiments, when the first detection circuit detects that the level of the HPD pin is changed from a low level to a high level, the first detection circuit enables the data processing chip to read the display device identification data of the display.

In some embodiments, the data processing chip includes a first HDMI access detection pin, and when the first detection circuit detects that the level of the HPD pin is changed from a low level to a high level, the first detection circuit sets the first HDMI access detection pin to a high level, so as to enable the data processing chip to read the display device identification data of the display.

In some embodiments, the first detection circuit includes a first resistor, a second resistor, and a first switch tube, a first end of the first switch tube is electrically connected to one end of the first resistor and the HPD pin, a second end of the first switch tube is electrically connected to the first power terminal, a third end of the first switch tube is electrically connected to the first HDMI connection detection pin, another end of the first resistor is grounded, and the second resistor is electrically connected between the second end of the first switch tube and the third end of the first switch tube.

In some embodiments, when the second detection circuit detects that the level of the HPD pin is changed from a low level to a high level, the second detection circuit enables the independent graphics card unit.

In some embodiments, the independent graphics card unit includes a second HDMI connection detection pin, and when the second detection circuit detects that the level of the HPD pin is converted from the low level to the high level, the second detection circuit sets the second HDMI hot-plug detection pin from the high level to the low level to enable the independent graphics card unit.

In some embodiments, the second detection circuit includes a first capacitor, a third resistor, a fourth resistor, a fifth resistor, and a second switch tube, one end of the first capacitor is electrically connected to one end of the third resistor and the HPD pin, the other end of the first capacitor is grounded, the other end of the third resistor is electrically connected to one end of the fourth resistor and the second end of the second switch tube, the other end of the fourth resistor is grounded, the first end of the second switch tube is electrically connected to the second HDMI connection detection pin and one end of the fifth resistor, the other end of the fifth resistor is electrically connected to the second power source terminal, and the third end of the second switch tube is grounded.

In some embodiments, the display includes a memory for display device identification data, and the data processing chip reads the memory-stored display device identification data through the display data channel bus DDC I2C.

An embodiment of the present application further provides an electronic device, including the HDMI display switching module.

Compared with the prior art, the HDMI display switching module and the electronic equipment have the advantages that the display functions of the independent display card and the integrated display card are switched based on the display parameters of the connected display, and the HDMI display supporting multiple versions is realized.

Drawings

Fig. 1 is a functional block diagram of an embodiment of an HDMI display switching module according to the present invention.

FIG. 2 is a functional block diagram of an embodiment of an electronic device of the present application.

Fig. 3 is a circuit diagram of an embodiment of a first detection circuit of the present application.

Fig. 4 is a circuit diagram of an embodiment of a second detection circuit of the present application.

Description of the main elements

HDMI connector 10

Main board 20

First detection circuit 30

Second detection circuit 40

HDMI display switching module 100

Display 200

Data processing chip 201

Independent graphics card unit 202

Integrated graphics card unit 203

Electronic device 300

First capacitor C1

First to fifth resistors R1, R2, R3, R4, R5

First to second switching tubes Q1, Q2

First HDMI access detection pin PCH _ HDMI _ HPD

Second HDMI access detection pin IFPC _ HPD

Detailed Description

The following detailed description will further illustrate the present application in conjunction with the above-described figures.

Please refer to fig. 1, which illustrates an HDMI display switching module 100 according to an embodiment of the present disclosure.

The HDMI display switching module 100 may include an HDMI connector 10, a main board 20, a first detection circuit 30 and a second detection circuit 40. The main board 20 may include a data processing chip 201, an independent graphics card unit 202, and an integrated graphics card unit 203. The HDMI connector 10 may be electrically connected to the main board 20, for example, the HDMI connector 10 may be disposed on the main board 20, and the pins of the HDMI connector 10 are electrically connected to the main board lines. The data Processing Chip 201 may be a Chip having an image data Processing capability in the motherboard 20, for example, the data Processing Chip 201 may be a Platform control Unit (PCH), a Central Processing Unit (CPU), a System On Chip (System On Chip), or the like. The independent graphic card unit 202 may refer to an independent graphic card electrically connected to the main board 20 through a graphic card slot. The integrated graphics card unit 203 may refer to an integrated graphics card integrated on the motherboard 20, for example, the integrated graphics card unit 203 may refer to an integrated graphics card integrated in a northbridge chip or a CPU.

The HDMI connector 10 includes an HPD pin, for example, the HDMI connector 10 may be a conventional 19-pin HDMI connector. The first detection circuit 30 is electrically connected to the HPD pin of the HDMI connector 10 and the Data processing chip 201, and when the HDMI connector 10 is electrically connected to the Display 200, for example, the HDMI connector 10 of the HDMI Display switching module 100 is connected to the Display 200 through an HDMI connection line, the first detection circuit 30 can enable the Data processing chip 201 based on the level of the HPD pin of the HDMI connector 10, so that the Data processing chip 201 can read the Display device Identification Data of the Display 200, for example, the Display device Identification Data is Extended Display Identification Data (EDID), and the EDID includes basic information and performance parameters (such as resolution and refresh rate) of the Display, for example, including supplier information, maximum image size, color setting, vendor preset, limit of frequency range, Display name, character string of serial number, and the like.

The first detection circuit 30 and the second detection circuit 40 may be disposed on the motherboard 20. For example, when the first detection circuit 30 detects that the level of the HPD pin of the HDMI connector 10 is changed from a low level to a high level, the first detection circuit 30 enables the data processing chip 201 to read the display device identification data of the display 200.

In some embodiments, the Display 200 may include a Display Data Channel (DDC) memory for storing the EDID, and the Data processing chip 201 may read the EDID stored in the DDC memory of the Display 200 through a DDC bus (e.g., a DDC I2C bus).

The second detecting circuit 40 is electrically connected to the HPD pin of the HDMI connector 10 and the independent graphics card unit 202, and the second detecting circuit 40 can enable the independent graphics card unit 202 based on the level of the HPD pin. The data processing chip 201 may control the independent graphic card unit 202 or the integrated graphic card unit 203 to transmit the HDMI signal to the display 200 based on the display device identification data so that the display 200 can display an image. The display 200 may be a display provided with an HDMI interface.

For example, when the second detection circuit 40 detects that the level of the HPD pin of the HDMI connector 10 is converted from the low level to the high level, the second detection circuit 40 enables the independent graphics card unit 202, so that the independent graphics card unit 202 enters the working state.

In some embodiments, when the display device identification data corresponds to the HDMI 1.4 standard or the HDMI 2.0 standard, the data processing chip 201 may control the integrated graphics card unit 203 to send an HDMI signal to the display 200. When the display device identification data corresponds to the HDMI 2.1 standard, the data processing chip 201 controls the independent graphics card unit 202 to send an HDMI signal to the display 200.

For example, when the display 200 having the HDMI interface is plugged or unplugged, the HPD pin of the HDMI connector 10 is pulled high by the connection to the HDMI device. This voltage variation Signal is used as a basis for determining whether an HDMI source (e.g., the HDMI display switching module 100 or the electronic device 300 of this embodiment) initiates EDID reading and starts sending a Transition Minimized Differential Signal (TMDS) Signal. The HPD signal is a detection signal generated from the display 200 and output to the HDMI source. When the display 200 is connected to or disconnected from the HDMI source via the HDMI interface, the HDMI source can detect this event via the HPD pin and respond accordingly.

When the HDMI source detects that the display 200 is connected to the HDMI source through the HPD pin, that is, the HPD pin is changed from a low level to a high level, the HDMI source considers that a display device is already connected, the HDMI source can read the EDID stored in the display 200 through the DDC bus, and the HDMI source can activate the TMDS signal transmission circuit to transmit an HDMI signal to the display 200 based on the working mode range of the display 200. If the EDID needs to be forcibly refreshed, an HPD signal can be initiated (the HPD is pulled down and then pulled up), so that the HDMI source end can read new EDID content. When the display 200 is disconnected from the HDMI source, the HDMI source may detect the disconnection of the display 200 through the HPD pin, and the HDMI source may disconnect the TMDS signal transmission circuit and stop transmitting the HDMI signal.

In some embodiments, when the HDMI source detects that the HPD pin voltage of the HDMI connector 10 is greater than 2V, it is determined that the display 200 is connected to the HDMI source through the HDMI interface. When detecting that the HPD pin voltage is less than 0.8V, it is determined that the display 200 has been disconnected from the HDMI source via the HDMI interface.

As shown in fig. 2, the HDMI display switching module 100 may be disposed in an electronic device 300, and the electronic device 300 may be a television, a personal computer, or the like.

Referring to fig. 3, a circuit diagram of the first detection circuit 30 is provided according to an embodiment of the present invention.

Taking the data processing chip 201 as the PCH for example, the data processing chip 201 includes a first HDMI access detection pin PCH _ HDMI _ HPD. The first detection circuit 30 includes a first resistor R1, a second resistor R2, and a first switch Q1. A first terminal of the first switch Q1 is electrically connected to one terminal of the first resistor R1 and the HPD pin of the HDMI connector 10, a second terminal of the first switch Q1 is electrically connected to the first power terminal VCC1, and a third terminal of the first switch Q1 is electrically connected to the first HDMI connection detection pin PCH _ HDMI _ HPD. The other end of the first resistor R1 is grounded, and the second resistor R2 is electrically connected between the second end and the third end of the first switch tube Q1.

When the level of the HPD pin of the HDMI connector 10 is switched from low level to high level, the first switch tube Q1 is turned on, and the first HDMI connection detection pin PCH _ HDMI _ HPD is set to high level, so as to enable the data processing chip 201 to read the display device identification data of the display 200.

In an embodiment, the resistance values of the first resistor R1 and the second resistor R2 may be set according to actual requirements, and are not limited herein. The first switch Q1 may be a transistor or a MOS transistor, for example, the first switch Q1 is an N-channel fet, the first terminal of the first switch Q1 is a drain of the N-channel fet, the second terminal of the first switch Q1 is a gate of the N-channel fet, and the third terminal of the first switch Q1 is a source of the N-channel fet.

Referring to fig. 4, a circuit diagram of the second detection circuit 40 is provided in accordance with an embodiment of the present invention.

The independent graphics card unit 202 includes a second HDMI access detection pin IFPC _ HPD. The second detection circuit 40 includes a first capacitor C1, a third resistor R3, a fourth resistor R4, a fifth resistor R5, and a second switch Q2. One end of the first capacitor C1 is electrically connected to one end of the third resistor R3 and the HPD pin of the HDMI connector 10, and the other end of the first capacitor C1 is grounded. The other end of the third resistor R3 is electrically connected to one end of the fourth resistor R4 and the second end of the second switch Q2, and the other end of the fourth resistor R4 is grounded. A first end of the second switch Q2 is electrically connected to the second HDMI connection detection pin IFPC _ HPD and one end of the fifth resistor R5, the other end of the fifth resistor R5 is electrically connected to the second power source terminal VCC2, and a third end of the second switch Q2 is grounded.

When the level of the HPD pin of the HDMI connector 10 is switched from low level to high level, the second switch tube Q2 is turned on, and the second HDMI hot plug detection pin IFPC _ HPD is set from high level to low level, so as to activate the independent graphics card unit 202.

In an embodiment, the capacitance of the first capacitor C1 may be set according to actual requirements, and is not limited herein. The resistance values of the third resistor R3, the fourth resistor R4 and the fifth resistor R5 may be set according to actual requirements, and are not limited herein. The second switch Q2 may be a transistor or a MOS transistor, for example, the second switch Q2 is an N-channel fet, the first terminal of the second switch Q2 is a drain of the N-channel fet, the second terminal of the second switch Q2 is a gate of the N-channel fet, and the third terminal of the second switch Q2 is a source of the N-channel fet. The first power source terminal VCC1 and the second power source terminal VCC2 may be power supply points on the motherboard 20, and the voltages of the first power source terminal VCC1 and the second power source terminal VCC2 may be 3.3V or 5V, etc.

The HDMI display switching module and the electronic equipment switch the display functions of the independent display card and the integrated display card based on the display parameters of the connected display, and realize the support of HDMI display of various versions.

Other corresponding changes or modifications which are obvious to those skilled in the art can be made according to the application scheme and the application concept of the present application in combination with the actual needs of the production, and the changes and modifications are all within the scope of the present disclosure.

Claims

1. The utility model provides a HDMI shows switches module, including the mainboard and with the HDMI connector that the mainboard electricity is connected, the HDMI connector includes the HPD pin, the mainboard includes data processing chip, independent display card unit and integrated display card unit, its characterized in that, HDMI shows switches module still includes first detection circuit and second detection circuit, first detection circuit electricity connect in the HPD pin reaches the data processing chip, when the HDMI connector is connected with the display electricity, first detection circuit enables based on the level of HPD pin the data processing chip reads the display device identification data of display, second detection circuit electricity connect in the HPD pin reaches independent display card unit, second detection circuit enables based on the level of HPD pin independent display card unit, the data processing chip is based on display device identification data control independent display card unit or integrated display card unit sends HDMI A signal is sent to the display.

2. The HDMI display switching module of claim 1 wherein said data processing chip controls said integrated graphics card unit to send said HDMI signal to said display when said display device identification data corresponds to HDMI 1.4 standard or HDMI 2.0 standard, and controls said independent graphics card unit to send said HDMI signal to said display when said display device identification data corresponds to HDMI 2.1 standard.

3. The HDMI display switching module of claim 1, wherein when said first detection circuit detects that the level of said HPD pin is changed from a low level to a high level, said first detection circuit enables said data processing chip to read the display device identification data of said display.

4. The HDMI display switching module of claim 3, wherein the data processing chip comprises a first HDMI access detection pin, and when the first detection circuit detects that the level of the HPD pin is converted from a low level to a high level, the first detection circuit sets the first HDMI access detection pin to a high level, so that the data processing chip can read the display device identification data of the display.

5. The HDMI display switching module according to claim 4, wherein the first detection circuit comprises a first resistor, a second resistor and a first switch tube, a first end of the first switch tube is electrically connected to one end of the first resistor and the HPD pin, a second end of the first switch tube is electrically connected to a first power source end, a third end of the first switch tube is electrically connected to the first HDMI connection detection pin, the other end of the first resistor is grounded, and the second resistor is electrically connected between the second end of the first switch tube and the third end of the first switch tube.

6. The HDMI display switching module of claim 1, wherein when the second detection circuit detects that the level of the HPD pin is changed from a low level to a high level, the second detection circuit enables the independent graphics card unit.

7. The HDMI display switching module of claim 6, wherein the independent graphics card unit comprises a second HDMI access detection pin, and when the second detection circuit detects that the level of the HPD pin is converted from a low level to a high level, the second detection circuit sets the second HDMI hot plug detection pin from the high level to the low level to enable the independent graphics card unit.

8. The HDMI display switching module of claim 7, wherein the second detection circuit comprises a first capacitor, a third resistor, a fourth resistor, a fifth resistor, and a second switch tube, wherein one end of the first capacitor is electrically connected to one end of the third resistor and the HPD pin, the other end of the first capacitor is grounded, the other end of the third resistor is electrically connected to one end of the fourth resistor and the second end of the second switch tube, the other end of the fourth resistor is grounded, the first end of the second switch tube is electrically connected to the second HDMI connection detection pin and one end of the fifth resistor, the other end of the fifth resistor is electrically connected to a second power source terminal, and the third end of the second switch tube is grounded.

9. The HDMI display switching module of any one of claims 1 to 8, wherein the display includes a memory for the display device identification data, the data processing chip reads the display device identification data stored by the memory through display data channel bus DDCI 2C.

10. An electronic device, comprising the HDMI display switching module of any one of claims 1 to 9.