CN116643711B

CN116643711B - Signal transmission circuit, mainboard and electronic equipment

Info

Publication number: CN116643711B
Application number: CN202310932661.7A
Authority: CN
Inventors: 张庭唯
Original assignee: Honor Device Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2023-07-27
Filing date: 2023-07-27
Publication date: 2024-05-10
Anticipated expiration: 2043-07-27
Also published as: CN116643711A

Abstract

The application provides a signal transmission circuit, a main board and electronic equipment, and relates to the technical field of circuits. In the electronic equipment, the signal transmission circuit is connected with a processor and a display screen of the electronic equipment. Under the condition that the electronic equipment is externally connected with the display card equipment, the display card equipment can directly transmit display signals to the display screen through the signal transmission circuit without passing through a processor of the electronic equipment, which is equivalent to that the display card equipment is directly connected with the display screen of the electronic equipment. Therefore, the display card device can directly drive the display screen of the electronic device, and cannot be limited by the performance of the processor of the electronic device, so that the performance of the display card device can be fully exerted, and the high-performance requirement of a user is met.

Description

Signal transmission circuit, mainboard and electronic equipment

Technical Field

The present application relates to the field of circuit technologies, and in particular, to a signal transmission circuit, a motherboard, and an electronic device.

Background

For some electronic devices with display functions, such as computers, mobile phones, tablet computers, etc., a graphics processor (graphics processing unit, GPU) is disposed in the electronic devices, and a display screen can be driven to display by a display signal generated by the GPU.

For example, for a notebook computer with a GPU integrated within a central processing unit (central processing unit, CPU), a display screen may be driven for display by a display signal generated by the GPU within the CPU. However, since the GPU is integrated in the CPU, the performance of the GPU is limited due to the limitation of space and other conditions, and the GPU is only suitable for low-power consumption scenes with low requirements on the performance of the GPU, such as web browsing, video playing, video conferencing and other scenes. But is difficult to adapt to scenes with high requirements on GPU performance, such as scenes of game running, video rendering, industrial product design, etc. In order to enable the notebook computer to be suitable for scenes with high requirements on GPU performance, the notebook computer can be externally connected with graphics card equipment integrated with the GPU, and a display screen is driven through the externally connected graphics card equipment.

In the prior art, however, the external display card device cannot directly drive the display screen. The display card device needs to transmit the display signal to the CPU, and then the CPU transmits the display signal to the display screen to drive the display screen. This is limited by the performance of the CPU, and causes a certain performance loss, which makes it difficult to fully exploit the GPU performance of the graphics card device. For example, when the CPU is busy, the display signal needs to be transmitted to the display screen after waiting for the CPU to be idle, so that the transmission delay of the display signal can be increased, the driving capability of the display card device to the display screen can be reduced, and the performance of the GPU of the display card device is lost. Therefore, how to make the electronic device meet the scene requirement of low power consumption, and fully exert the GPU performance of the video card device when the video card device is externally connected becomes a technical problem to be solved.

Disclosure of Invention

Some embodiments of the present application provide a signal transmission circuit, a motherboard and an electronic device, and the following description of the present application refers to the following aspects, which may be referred to as embodiments and advantageous effects.

In a first aspect, the present application provides an electronic device comprising a display screen, a signal transmission circuit, and a first processor; the signal transmission circuit is connected with the display screen and the first processor, and is used for transmitting a first display signal of the external display card device to the display screen under the condition that the electronic device is connected with the external display card device, and transmitting a second display signal of the first processor to the display screen under the condition that the electronic device is not connected with the external display card device.

The first processor of the electronic device is a CPU of the electronic device.

According to the embodiment of the application, under a high-performance scene, namely under the condition that the electronic equipment is externally connected with the display card equipment, the display card equipment can directly transmit the display signal to the display screen through the signal transmission circuit without passing through the first processor of the electronic equipment, which is equivalent to that the display card equipment is directly connected with the display screen of the electronic equipment. Therefore, the display card device can directly drive the display screen of the electronic device, and cannot be limited by the performance of the processor of the electronic device, so that the performance of the display card device can be fully exerted, and the high-performance requirement of a user is met. Under the low power consumption scene, namely under the condition that the electronic equipment is not externally connected with the display card equipment, the signal transmission circuit can transmit the second display generated by the first processor of the electronic equipment to the display screen. The second display signal is generated by the GPU of the first processor, which is internally integrated, and the power consumption of the GPU of the first processor is lower, so that the low-power consumption scene requirement of a user can be met.

In some embodiments, the signal transmission circuit includes: the display device comprises an input part, a control part and an output part, wherein the control part is respectively connected with the input part and the output part, the output part is connected with the input part, the control part is used for controlling the input part to receive a first display signal output by the display card device under the condition that the electronic device is externally connected with the display card device and transmitting the first display signal to a display screen through the output part, and the control part is also used for controlling the output part to transmit a second display signal output by the first processor to the display screen under the condition that the electronic device is not externally connected with the display card device.

According to the embodiment of the application, in a high-performance scene, namely, in the case that the electronic device is externally connected with the display card device, the control part can control the input part to receive the first display signal output by the display card device and transmit the first display signal to the display screen through the output part. The first display signal is transmitted to the display screen through the input part and the output part, and the transmission path of the first display signal does not pass through the first processor of the electronic equipment, so that the performance limit of the first processor is avoided, the performance loss can be reduced, the performance of the display card equipment can be fully exerted, and the high performance requirement of a user is met. Under the low power consumption scene, namely under the condition that the electronic equipment is not externally connected with the display card equipment, the control part can control the output part to transmit the second display signal output by the first processor to the display screen. The second display signal is generated by the GPU of the first processor, which is internally integrated, and the power consumption of the GPU of the first processor is lower, so that the low-power consumption scene requirement of a user can be met.

In some embodiments, the control part is further configured to transmit the first control signal to the input part and transmit the second control signal to the output part when receiving the first signal output by the display card device and the second signal output by the first processor; transmitting a third control signal to the output section if the first signal and/or the second signal is not received;

the input part is used for receiving a first display signal output by the display card equipment under the condition of receiving the first control signal, and transmitting the first display signal to the output part;

The output part is used for transmitting the first display signal to the display screen under the condition of receiving the second control signal; transmitting a second display signal output by the first processor to the display screen under the condition that the third control signal is received;

the first signal is output when the display card device is connected with the electronic device; the second signal is output by the first processor when the electronic device receives a first operation, and the first operation is used for opening a using function of the display card device in an operating system of the electronic device.

According to the embodiment of the application, under the condition that the electronic equipment is externally connected with the display card equipment, a user can select the functions through the operating system of the electronic equipment. When the user turns on the use function of the graphics card device, the electronic device may use the graphics card device to drive the display screen, that is, transmit the first display signal of the graphics card device to the display screen. It will be understood that when the user does not open the function of the graphics card device, or when the graphics card device is not successfully connected, the control unit does not transmit the first control signal to the input unit and the second control signal to the output unit, but transmits the third control signal to the output unit, and at this time, the output unit does not transmit the first display signal to the display screen, but transmits the second display signal output by the first processor to the display screen. Therefore, the display screen can be prevented from being driven by the display card device by mistake due to connection failure or the fact that the user does not open the using function of the display card device.

In some embodiments, the control section is further configured to transmit a fourth control signal to the input section if the second signal is not received;

the input part is also used for receiving first data output by input equipment externally connected with the electronic equipment under the condition of receiving the fourth control signal, and transmitting the first data to the first processor.

In some embodiments, the control section includes a level shifter, a first controller, and a gate circuit having a first input coupled to the level shifter and a second input coupled to the first controller, wherein,

The level converter is used for transmitting a low-level signal to the first input end of the gate circuit under the condition that the first signal transmitted by the display card device is received; transmitting a high level signal to a first input of the gate circuit if the first signal is not received;

The first controller is used for transmitting a low-level signal to the second input end of the gate circuit under the condition that the second signal transmitted by the first processor is received; transmitting a high level signal to a second input of the gate circuit if the second signal is not received;

The gate circuit is used for transmitting a second control signal to the output part under the condition that the first input end and the second input end are both input with low-level signals; when the first input terminal and/or the second output terminal inputs the high-level signal, the third control signal is transmitted to the output section.

In some embodiments, the first controller is further configured to output a fourth control signal if the second signal is not received.

In some embodiments, the input includes a selector and a second controller, the selector being connected to the second controller;

the selector is used for transmitting the first display signal output by the display card device to the second controller under the condition that the first control signal transmitted by the control part is received;

the second controller is used for transmitting the first display signal to the output part.

According to the embodiment of the application, the selector and the second controller can transmit the first display signal output by the display card device to the output part, and the output part transmits the first display signal to the display screen, so that the first processor of the electronic device can be bypassed, and the performance limitation of the first processor is avoided.

In some embodiments, the selector is further configured to receive a fourth control signal output by the first controller and the first data output by the input device, and transmit the first data output by the input device to the first processor if the fourth control signal is received.

According to the embodiment of the application, in the case that the electronic device is externally connected with the input device, for example, in the case that the electronic device is externally connected with a USB flash disk, a mobile hard disk, a mouse, a keyboard, a printer and other devices, the electronic device can normally read the data of the input device through the selector.

In a second aspect, an embodiment of the present application provides a signal transmission circuit, provided in an electronic device, the circuit including: the display card comprises an input part, a control part and an output part, wherein the control part is respectively connected with the input part and the output part, the output part is connected with the input part, the control part is used for controlling the input part to receive a first display signal output by the display card device and transmitting the first display signal to a display screen of the electronic device through the output part under the condition that the electronic device is not externally connected with the display card device, and the control part is also used for controlling the output part to transmit a second display signal output by a first processor of the electronic device to the display screen of the electronic device under the condition that the electronic device is not externally connected with the display card device.

In a third aspect, an embodiment of the present application provides a motherboard, including the signal transmission circuit provided in the second aspect. The advantages achieved by the third aspect may refer to the advantages of the signal transmission circuit provided by any embodiment of the second aspect, which are not described herein.

Drawings

FIG. 1A is an exemplary diagram of an electronic device according to an embodiment of the present application;

fig. 1B is a circuit example diagram of an electronic device according to an embodiment of the present application;

fig. 2A is an exemplary diagram of an external display card device of an electronic device according to an embodiment of the present application;

Fig. 2B is an exemplary diagram of a display signal transmission process of the display card device according to the embodiment of the present application;

fig. 3A is a second exemplary diagram of an external display card device of an electronic device according to an embodiment of the present application;

Fig. 3B is an exemplary diagram of an electronic device provided in an embodiment of the present application without a display card device connected to the electronic device;

Fig. 4A is an exemplary diagram III of an external display card device of an electronic device according to an embodiment of the present application;

fig. 4B is an exemplary diagram two of an electronic device provided in an embodiment of the present application without a display card device connected to the electronic device;

Fig. 4C is an exemplary diagram of an external input device of an electronic device according to an embodiment of the present application;

fig. 5 is a schematic diagram of an external display card device of an electronic device according to an embodiment of the present application;

FIG. 6 is an exemplary diagram of an interface of an electronic device according to an embodiment of the present application;

Fig. 7 is a third exemplary diagram of an electronic device provided in an embodiment of the present application without a display card device connected to the electronic device;

fig. 8 is a second exemplary diagram of an external input device of an electronic device according to an embodiment of the present application;

fig. 9A is a fifth exemplary diagram of an external display card device of an electronic device according to an embodiment of the present application;

fig. 9B is an exemplary diagram fourth of an electronic device provided in an embodiment of the present application without a display card device connected to the electronic device;

fig. 9C is an exemplary diagram three of an external input device of an electronic device according to an embodiment of the present application.

Description of the embodiments

The embodiment of the application is used for providing a signal transmission circuit. The electronic equipment using the signal transmission circuit provided by the application can meet the low-power consumption scene requirement of a user, and can directly connect the external display card equipment with a display screen of the electronic equipment when the external display card equipment is connected, so that the GPU performance of the display card equipment can be fully exerted.

Fig. 1A is an electronic device provided in an embodiment of the present application. Referring to fig. 1A, an electronic device 101 includes a display screen 10A and a CPU (not shown). During operation of the electronic device 101, a CPU thereof may generate a display signal for transmission to the display screen 10A to drive the display screen 10A for display.

The electronic device of the present application may be any electronic device that supports a display function, for example, a desktop computer, a notebook computer, a tablet computer, etc., and the specific form of the electronic device is not limited in the present application. A notebook computer will be hereinafter exemplified as the electronic device.

In some embodiments, as shown in fig. 1B, the electronic device 101 includes a display screen 10A and a motherboard 10B. The main board 10B includes a CPU 20 and an interface M1, and the display screen 10A includes an interface M2. The CPU 20 has a GPU 21 integrated therein. The CPU 20 is connected to the interface M1, and the interface M1 of the main board 10B is connected to the interface M2 of the display screen 10A. In some embodiments, the interfaces M1 and M2 may be video image array (VGA) interfaces, high definition multimedia (high definition multimedia interface, HDMI) interfaces, display interfaces (DP), and the like, without limitation.

In the running process of the electronic device 101, the CPU 20 on the motherboard 10B of the electronic device 101 may generate graphics data, transmit the graphics data to the GPU 21, render the graphics data by the GPU 21 to obtain a corresponding display signal, and then transmit the display signal to the display screen 10A to drive the display screen 10A to display. Because the GPU 21 is integrated inside the CPU 20 and limited by factors such as space, the performance of the GPU is usually not high, and the GPU is suitable for some low-power consumption scenes with high requirements on GPU performance, such as web browsing, video playing, video conferencing, etc., but is difficult to be suitable for scenes with high requirements on GPU performance, such as game running, video rendering, industrial product design, etc.

In some embodiments, to enable the electronic device 101 to be used in a scenario where the GPU performance requirements are high, the electronic device 101 may be connected to a graphics card device 102 that integrates a high performance GPU, as shown in fig. 2A. When the electronic device 101 runs an application with high requirements on GPU performance, graphics data generated by the CPU 20 may be rendered by the external graphics card device 102.

For example, as shown in fig. 2B, the graphics card device 102 includes the GPU 31 and the interface M3, the main board 10B of the electronic device 101 includes the interface M4, the interface M3 of the graphics card device 102 is connected to the interface M4 of the electronic device 101, and the interface M4 of the electronic device 101 is connected to the CPU 20. When the electronic device 101 runs the game application, the CPU 20 of the electronic device 101 may transmit the graphics data to the GPU 31 of the video card device 102 through the interface M4 and the interface M3 for rendering, so as to obtain a corresponding display signal. Then, the GPU 31 of the graphic card device 102 transmits the display signal to the CPU 20 of the electronic device 101 through the interface M3 and the interface M4, and the CPU 20 transmits the display signal to the display screen 10A to drive the display screen 10A. In this way, the electronic device 101 may normally load the gaming application.

In some embodiments, the interfaces M3 and M4 may be universal serial bus (universal serial bus, USB) interfaces, mini-serial advanced technology attachment (MINI SERIAL ADVANCED technology attachment, miniSATA) interfaces, external serial SERIAL ADVANCED technology attachment, e-SATA) interfaces, and the like, without limitation.

It will be appreciated that, in the example shown in fig. 2B, the GPU 31 of the graphics card device 102 cannot be directly connected to the display screen 10A of the electronic device 101, but is indirectly connected to the display screen 10A through the CPU 20 of the electronic device 101, so that the display signal output by the GPU 31 cannot directly drive the display screen 10A, but indirectly drives the display screen 20 through the CPU 20, which is limited by the internal circuit structure of the electronic device 101. This may result in excessive power consumption, resulting in loss of GPU performance of the graphics card device 102, and GPU performance of the graphics card device 102 may be limited by the performance of the CPU 20. For example, when the CPU 20 is busy, the CPU 20 needs to wait for idle to transmit the display signal to the display screen 10A, which increases the transmission delay of the display signal, reduces the driving capability of the graphics card device 102 to the display screen 10A, and causes the GPU performance of the graphics card device 102 to be lost. As such, it is difficult to fully exploit the GPU capabilities of the graphics card device 102, thereby affecting the user's experience. For example, when the electronic device 101 runs a game application, if the GPU performance of the graphics card device 102 is not fully exerted, a phenomenon that the screen is not smooth may occur when the game application runs for a long time.

In the above embodiment, for the low power consumption scenario, since the power consumption of the electronic device 101 itself is low, the external display card device 102 is not required. For high performance scenarios, the electronic device 101 needs to be externally connected to the graphics card device 102 to meet the high performance requirements. However, when the electronic device 101 is externally connected to the graphics card device 102, the graphics card device 102 cannot directly drive the display screen 10A due to the limitation of the internal circuit structure, and thus it is difficult to fully exert the GPU performance of the graphics card device 102. That is, the electronic device 101 may meet the low power consumption scenario requirements of the user, but in a high performance scenario, it is difficult to fully exploit the GPU performance of the graphics card device 102 when the electronic device 101 is externally connected to the graphics card device 102.

In order to solve the above technical problems, the present application provides a signal transmission circuit. The signal transmission circuit can be directly connected with the display card equipment externally connected with the electronic equipment and the display screen of the electronic equipment, and transmits the display signal of the display card equipment externally connected with the electronic equipment to the display screen of the electronic equipment, so that the display signal is not required to be transmitted through the CPU of the electronic equipment. For example, the signal transmission control circuit may be disposed on a motherboard of the electronic device, and connect a display card device connected to the electronic device and a display screen of the electronic device through an interface on the motherboard. The signal transmission circuit includes an input section, a control section, and an output section. The control part is connected with the input part and the output part respectively, and the input part is connected with the output part. The control part is used for controlling the input part to receive the display signal output by the display card device and transmitting the display signal to the display screen of the electronic device through the output part under the condition that the electronic device is externally connected with the display card device. Therefore, the display card device can directly drive the display screen of the electronic device to display, avoid being limited by the CPU of the electronic device, and fully exert the performance of the display card device. And the control part is also used for controlling the output part to transmit the display signal output by the processor of the electronic equipment to the display screen of the electronic equipment under the condition that the electronic equipment is not externally connected with the display card equipment. Therefore, when the display card device is not externally connected, the electronic device can drive the display screen through the CPU of the electronic device so as to save power consumption.

Specifically, fig. 3A shows a signal transmission circuit. As shown in fig. 3A, the signal transmission circuit 300A may be provided in the motherboard 10B of the electronic device 101. The signal transmission circuit 300A may be connected to the interface H1 of the display card device 102 through the interface H2 on the main board 10B, and to the interface H4 of the display screen 10A through the interface H3 on the main board 10B. In a high-performance scenario, that is, a scenario in which the electronic device 101 is externally connected to the graphics card device 102, the CPU 20 of the electronic device 101 transmits graphics data to the graphics card device 102 through the signal transmission circuit 300A. The signal transmission circuit 300A does not perform some intermediate processing on the graphics data during the process of transmitting the graphics data, but directly transmits the graphics data to the graphics card device 102, which is equivalent to the CPU 20 in fig. 2B directly transmitting the graphics data to the graphics card device 102, without performance consumption. After receiving the graphics data, the graphics card device 102 performs rendering processing on the graphics data through the GPU 31 to obtain a first display signal. Then, the graphic card device 102 transmits the first display signal to the signal transmission circuit 300A, and the signal transmission circuit 300A transmits the first display signal to the display screen 10A to drive the display screen 10A to display. That is, the first display signal generated by the graphics card device 102 may be directly transmitted to the display screen 10A, without being transmitted to the display screen 10A through the CPU 20, which is equivalent to that the graphics card device 102 is directly connected to the display screen 10A. The display card device 102 can directly drive the display screen 10A, so that the performance limit of the CPU 20 is avoided, the GPU performance loss of the display card device 102 is reduced, the GPU performance of the display card device 102 is fully exerted, and the high performance requirement of a user is met. For example, when the user uses the electronic device 101 to run the game application, the display device 102 externally connected to the electronic device 101 directly drives the display screen 10A, so that the running of the game application is smoother.

In a low power consumption scenario, that is, a scenario in which the electronic device 101 is not externally connected to the graphics card device 102, as shown in fig. 3B, the GPU 21 integrated inside the CPU 20 performs rendering processing on the graphics data generated by the CPU 20 to obtain a second display signal. The CPU 20 then transmits the second display signal to the signal transmission circuit 300A, and the signal transmission circuit 300A outputs the second signal to the display screen 10A to drive the display screen 10A to display. Because the power consumption of the GPU 21 inside the CPU 20 is low, the low power consumption scene requirement of the user can be satisfied. For example, when a user uses the electronic device 101 to perform a video conference, because the electronic device 101 is not externally connected with the display card device 102, the power consumption is lower, and the endurance time of the electronic device 101 can be improved, thereby meeting the scene requirement of long endurance.

It can be appreciated that when the signal transmission circuit 300A provided by the present application is disposed on the motherboard 10B of the electronic device 101, the scene requirements of low power consumption and high performance can be considered. For example, in a high performance scenario, the graphics card device 102 may be directly coupled to the display screen 10A via the signal transmission circuit 300A, rather than indirectly coupled to the display screen 10A via the CPU 20. The display screen 10A can be directly driven by the display card device 102 through the signal transmission circuit 300A without being limited by the performance of the CPU 20, so that the GPU performance of the display card device 102 is fully exerted, and the high performance scene requirement of a user is met. In the low power consumption scenario, the CPU 20 of the electronic device 101 may drive the display screen 10A through the signal transmission circuit 300A, so as to save power consumption and meet the low power consumption scenario requirement of the user.

The specific structure and principle of the signal transmission circuit 300A will be described below.

Fig. 4A shows a structural example diagram of a signal transmission circuit. Referring to fig. 4A, the signal transmission circuit 300A includes an input section 30, a control section 40, and an output section 50. The a end of the input unit 30 is connected to the interface H2, the B end of the control unit 40 is connected to the B end of the input unit 30, the C end of the input unit 30 is connected to the CPU 20, and the D end of the input unit 30 is connected to the B end of the output unit 50. The a end of the control unit 40 is connected to the interface H2, the C end of the control unit 40 is connected to the CPU 20, and the D end of the control unit 40 is connected to the D end of the output unit 50. The a end of the output unit 50 is connected to the GPU 21 of the CPU 20, and the C end of the output unit 50 is connected to the interface H3.

The a terminal of the input unit 30 is configured to receive the first display signal output by the graphics card device 102 and output graphics data. The B terminal of the input unit 30 is configured to receive the first control signal or the fourth control signal output from the B terminal of the control unit 40. The C-terminal of the input section 30 is for receiving graphics data output from the CPU 20. The D terminal of the input unit 30 is used for outputting a first display signal.

The a terminal of the control unit 40 is configured to receive the first signal output by the graphics card device 102. The B terminal of the control unit 40 is configured to output the first control signal or the fourth control signal. The C terminal of the control section 40 is configured to receive the second signal output from the CPU 20. The D terminal of the control unit 40 is configured to output the first control signal or the second control signal. The first signal is output when the graphics card device 102 and the electronic device 101 are successfully connected. The second signal is output by the CPU 20 after the user opens the use function of the graphic card device 102 in the operating system of the electronic device 101. For the sake of descriptive consistency, the output process of the first signal and the second signal is described below.

The a terminal of the output unit 50 is configured to receive the second display signal output by the CPU 20. The B terminal of the output unit 50 is configured to receive the first display signal output from the B terminal of the input unit 30. The C-terminal of the output part 50 is used for outputting the first display signal or the second display signal. The D terminal of the output unit 50 is configured to receive the first control signal or the second control signal output from the D terminal of the control unit 40.

In the high performance scenario, as shown in fig. 4A, when the electronic device 101 is externally connected to the display card device 102, the a end of the control portion 40 receives a first signal output by the display card device 102, and the C end of the control portion 40 receives a second signal output by the CPU 20, and the B end of the control portion 40 transmits a first control signal to the B end of the input portion 30, so as to control the a end of the input portion 30 to receive the display signal generated by the display card device 102. And, the D terminal of the control part 40 transmits the second control signal to the D terminal of the output part 50 to control the C terminal of the output part 50 to output the display signal generated by the graphic card device 102. During operation of the electronic device 101, the CPU 20 generates graphics data and transmits the graphics data to the C-terminal of the input section 30. After the C-terminal of the input section 30 receives the graphics data, the a-terminal of the input section 30 transmits the graphics data to the graphic card device 102 through the interface H2 and the interface H1. The input unit 30 does not perform intermediate processing on the graphics data during the process of transmitting the graphics data, but only transmits the graphics data, which is equivalent to directly connecting the CPU 20 to the graphics card device 102, so that performance loss can be avoided. After receiving the graphics data of the CPU 20, the graphics card device 102 performs rendering processing on the graphics data through its GPU 31 to obtain a first display signal, and transmits the first display signal to the a end of the input portion 30 through the interface H1 and the interface H2, and then transmits the first display signal to the B end of the output portion 50 through the D end of the input portion 30. In this case, the B terminal of the output unit 50 may receive the first display signal generated by the video card apparatus 102, and the a terminal of the output unit 50 may also receive the second display signal generated by the CPU 20 of the electronic apparatus 101. When the D terminal of the output part 50 receives the second control signal transmitted from the D terminal of the control part 40, the C terminal of the output part 50 outputs only the first display signal. The first display signal is transmitted to the display screen 10A through the interface H3 and the interface H4, and the display screen 10A is driven to display. It will be understood that the first display signal is transmitted from the graphics card device 102 to the display screen 10A through the interface H1, the interface H2, the input unit 30, the output unit 50, the interface H3 and the interface H4, and the transmission path does not pass through the CPU 20, which is equivalent to that the graphics card device 102 bypasses the CPU 20 and is directly connected to the display screen 10A. In this way, the display card device 102 can directly drive the display screen 10A without being limited by the performance of the CPU 20, so that the GPU performance of the display card device 102 can be fully exerted, and the high performance scene requirement of the user can be met.

In a low power consumption scenario, referring to fig. 4B, when the electronic device 101 is not externally connected to the graphics card device 102, the a end of the control portion 40 does not receive the first signal transmitted by the graphics card device 102, and the C end of the control portion 40 does not receive the second signal transmitted by the CPU 20, and the D end of the control portion 40 transmits the third control signal to the D end of the output portion 50, so as to control the C end of the output portion 50 to output the second display signal transmitted by the CPU 20 to the a end of the output portion 50. The second display signal is obtained after the GPU 21 integrated inside the CPU 20 performs rendering processing on the graphics data generated by the CPU 20. The second display signal is transmitted to the display screen 10A through the interface H3 and the interface H4, and the display screen 10A is driven to display. Because the power consumption of the GPU 21 integrated inside the CPU 20 is low, when the electronic device 101 is not externally connected with the display card device 102, the CPU 20 directly drives the display screen 10A, so that the power consumption can be reduced, and the low-power consumption scene requirement of a user can be met.

In summary, since the signal transmission circuit 300A is disposed on the motherboard 10B of the electronic device 101, the electronic device 101 can not only meet the scene requirement of low power consumption, but also enable the display card device 102 to directly connect with the display screen 10A of the electronic device 101 when the display card device 102 is externally connected, so as to fully exert the GPU performance of the display card device 102.

In some embodiments, referring to fig. 4C, when the electronic device 101 is externally connected to the input device 103, the B terminal of the control portion 40 transmits a fourth control signal to the B terminal of the input portion 30 to control the a terminal of the input portion 30 to receive the first data transmitted by the input device 103. The interface H5 of the input device 103 is connected to the interface H2 of the electronic device 101. The input device 103 may transmit the first data to the CPU 20 through the interface H5, the interface H2, and the input section 30. Thus, when the electronic device 101 is externally connected to the input device 103, the electronic device 101 can normally read the data of the input device 103. The input device 103 may be a data storage device such as a usb disk or a mobile hard disk, or may be a device for inputting instructions such as a mouse or a keyboard, which is not limited in any way. The first data may be data such as pictures, text, audio, video, etc., or packaged data of a mouse event, or other types of data, which is not limited in any way.

On the basis of the above-described embodiment, referring to fig. 5, the input section 30 includes the selector 31 and the second controller 32. The control section 40 includes a first controller 41, a level shifter 42, and a gate circuit 43. The a-terminal of the selector 31 is connected to the interface H2, the b-terminal of the selector 31 is connected to the a-terminal of the first controller 41, the c-terminal of the selector 31 is connected to the CPU 20, and the d-terminal of the selector 31 is connected to the a-terminal of the second controller 32. The a-terminal of the selector 31 is the a-terminal of the input section 30, the B-terminal of the selector 31 is the B-terminal of the input section 30, and the C-terminal of the selector 31 is the C-terminal of the input section 30. The B terminal of the second controller 32 is connected to the CPU 20, and the c terminal of the second controller 32 is connected to the B terminal of the output unit 50. The b-terminal of the second controller 32 is also the C-terminal of the input 30. The a-terminal of the first controller 41 is the B-terminal of the control unit 40, the B-terminal of the first controller 41 is connected to the CPU 20, and the c-terminal of the first controller 41 is connected to the a-terminal of the gate 43 (i.e., the second input terminal of the gate 43). The a terminal of the level shifter 42 is the a terminal of the control unit 40, and is connected to the interface H2. The b terminal of the level shifter 42 is connected to the b terminal of the gate 43 (i.e. the first input terminal of the gate 43). The c terminal of the gate 43 (i.e., the output terminal of the gate 43) is the D terminal of the control unit 40, and is connected to the D terminal of the output unit 50.

The a-terminal of the level shifter 42 is configured to receive the first signal transmitted by the graphics card device 102. The b-terminal of the level shifter 42 is configured to output a high-level signal, i.e., a default high-level signal, when the a-terminal of the level shifter 42 does not receive the first signal transmitted by the video card device 102, and output a low-level signal when the a-terminal of the level shifter 42 receives the first signal transmitted by the video card device 102. Wherein the first signal characterizes that the graphics card device 102 and the electronic device 101 are successfully connected.

The a-terminal of the first controller 41 is used for outputting a first control signal or a fourth control signal. The b terminal of the first controller 41 is configured to receive the second signal output by the CPU 20. The c-terminal of the first controller 41 is configured to output a high-level signal, i.e., a default high-level signal, when the b-terminal of the first controller 41 does not receive the second signal output by the CPU 20, and to output a low-level signal when the b-terminal of the first controller 41 receives the second signal output by the CPU 20. Wherein the second signal characterizes the electronic device 101 allowing the graphics card device 102 to drive the display screen 10A. The a-terminal of the first controller 41 is configured to output a first control signal when the b-terminal of the first controller 41 receives the second signal transmitted by the CPU 20, and output a fourth control signal when the second signal transmitted by the CPU 20 is not received, i.e. the a-terminal of the first controller 41 outputs the fourth control signal by default. The b terminal of the selector 31 opens the connection channel with the second controller 32 when receiving the first control signal, and closes the connection channel with the second controller 32 when receiving the fourth control signal.

The a terminal of the gate 43 is configured to receive a high level signal or a low level signal output from the c terminal of the first controller 41. The b terminal of the gate 43 is for receiving the high level signal or the low level signal output from the b terminal of the level shifter 42. The c-terminal of the gate 43 is configured to output a second control signal when both the a-terminal and the b-terminal of the gate 43 receive the low-level signal, and to output a third control signal when the a-terminal and/or the b-terminal of the gate 43 receive the high-level signal. In some embodiments, the second control signal is a low level signal and the third control signal is a high level signal.

In some embodiments, in a high performance scenario, as shown in fig. 5, when the electronic device 101 is connected to the graphics device 102, the graphics device 102 may transmit the first signal to the a-side of the level shifter 42 through the interface H1 and the interface H2. When the a-terminal of the level shifter 42 receives the first signal, it indicates that the display card device 102 is successfully connected to the electronic device 101, and the b-terminal of the level shifter 42 outputs a low-level signal.

After the electronic apparatus 101 is externally connected to the display card apparatus 102, a user may perform a function selection operation on an Operating System (OS) of the electronic apparatus 101 so that the electronic apparatus 101 allows the display card apparatus 102 to drive the display screen 10A. For example, referring to fig. 6, when the electronic device 101 is externally connected to the graphics card device 102, the OS of the electronic device 101 may pop up the prompt pop-up window 60 on the display screen 10A to prompt the user to "detect that the graphics card device is locally connected, please determine whether to use the externally connected graphics card device. After the user clicks the ok button 61 on the prompt pop 60, the usage function of the graphic card device 102 is opened, and the graphic card device 102 can drive the display screen 10A of the electronic device 101.

In some embodiments, when the user clicks the ok button 61 on the reminder pop 60, the OS of the electronic device 101 may transmit a first instruction to the CPU 20 of the electronic device 101. As shown in fig. 5, the CPU 20 receives the first instruction and transmits the second signal to the b terminal of the first controller 41. When the b end of the first controller 41 receives the second signal, the c end of the first controller 41 outputs a low level signal, and the a end of the first controller 41 outputs a first control signal. After receiving the low level signal at both the a terminal and the b terminal of the gate 43, the c terminal of the gate 43 outputs a second control signal. After receiving the first control signal at the b-terminal of the selector 31, the selector 31 opens a connection channel with the second controller 32. Data may be transferred between the selector 31 and the second controller 32. At this time, the CPU 20 may transmit the graphics data to the GPU 31 of the graphics card device 102 through the second controller 32, the selector 31, the interface H2, and the interface H1, and the GPU 31 performs rendering processing on the graphics data to obtain the first display signal. The second controller 32 and the selector 31 do not perform some intermediate processing on the graphics data during the process of transmitting the graphics data, but only transmit the graphics data, which is equivalent to directly connecting the CPU 20 with the graphics card device 102, so that performance loss can be avoided. The graphic card apparatus 102 then transmits the first display signal to the B terminal of the output part 50 through the interface H1, the interface H2, the selector 31, and the second controller 32. After the D-terminal and the B-terminal of the output part 50 receive the second control signal and the first display signal, respectively, the C-terminal of the output part 50 outputs the first display signal in response to the second control signal. The first display signal is transmitted to the display screen 10A through the interface H3 and the interface H4. After receiving the first display signal, the display screen 10A displays based on the first display signal.

In the embodiment described in fig. 5 and 6, the first display signal is directly connected to the display screen 10A without passing through the CPU 20, which is equivalent to the fact that the display card device 102 bypasses the CPU 20 during the process of transmitting the first display signal from the display card device 102 to the display screen 10A. In this way, the display card device 102 can directly drive the display screen 10A without being limited by the performance of the CPU 20, so that the GPU performance of the display card device 102 can be fully exerted, and the high performance scene requirement of the user can be met.

In some embodiments, in a low power consumption scenario, as shown in fig. 7, when the electronic device 101 is not externally connected to the display card device 102, the b terminal of the first controller 41 does not receive the second signal output by the CPU 20, the a terminal of the first controller 41 outputs the fourth control signal, and the c terminal of the first controller 41 outputs the high level signal. Since the a-terminal of the level shifter 42 does not receive the first signal output from the graphic card device 102, the b-terminal of the level shifter 42 outputs a high-level signal. Since both the a-terminal and the b-terminal of the gate 43 receive the high-level signal, the c-terminal of the gate 43 outputs the third control signal. When the D-terminal of the output section 50 receives the third control signal, the C-terminal of the output section 50 outputs the second display signal output by the CPU 20 received by the a-terminal. The second display signal is transmitted to the display screen 10A through the interface H3 and the interface H4. After receiving the second display signal, the display screen 10A displays based on the second display signal.

In the embodiment described in fig. 7, when the electronic device 101 is not externally connected with the display card device 102, the CPU 20 directly drives the display screen 10A, and the power consumption of the GPU 21 integrated inside the CPU 20 is low, so that the low power consumption scene requirement of the user can be met.

In some embodiments, in a low power scenario, referring to fig. 8, the electronic device 101 may also be external to the input device 103. The input device 103 includes an interface H5. The interface H5 of the input device 103 is connected to the interface H2 of the electronic device 101. As shown in fig. 8, when the device externally connected to the electronic device 101 is not the graphic card device 102 but the input device 103, the a-terminal of the first controller 41 transmits a fourth control signal to the b-terminal of the selector 31, and the selector 31 closes the connection channel with the second controller 32 in response to the fourth control signal. At this time, the input device 103 may transmit the first data to the CPU 20 through the interface H5, the interface H2, and the selector 31, and the CPU 20 performs certain processing on the first data, for example, modifying the first data, or the like. At this time, the display screen 10A is still driven by the CPU 20 to display.

In the embodiment described in fig. 8 above, when the electronic device 101 is externally connected to the input device 103, the input device 103 may transmit its own data to the CPU 20 of the electronic device 101 through the interface H5, the interface H2, and the selector 31. That is, the electronic device 101 may read data of the input device 103. Therefore, the requirements of users for external USB flash disk, mobile hard disk, mouse, keyboard and other input devices can be met.

In some embodiments, the first controller 41 may be an embedded controller (embedded controller, EC). The level shifter 42 may be a Pull Down (PD) resistor or a pull down circuit (abbreviated as "PD"). The gate 43 may be an or gate. The selector 31 may be a universal serial bus selector (or referred to as a "USB Switch"). The second controller 32 may be a lightning controller. The output 50 may be an embedded display port (embedded displayport, eDP) selector (or referred to as "EDP SWITCH"). The interface H1, the interface H2, and the interface H5 may be TypeC interfaces having a lightning function (a signal transmission function), and the interface H3 and the interface H4 may be eDP interfaces.

In other embodiments, the interfaces H1, H2 and H5 may be miniSATA, e-SATA, or other types of interfaces, and the interfaces H3 and H4 may be VGA, HDMI, DP, or other types of interfaces, which are not limited.

Illustratively, in a high performance scenario, referring to fig. 9A, when the electronic device 101 is externally connected to the graphics device 102, the graphics device 102 may transmit the first signal to the PD 42' through the TypeC interface H1' and the TypeC interface H2 '. When the PD 42' receives the first signal, it indicates that the video card apparatus 102 is successfully connected to the electronic apparatus 101, and at this time, the output pin (PD Gpio) of the PD 42' outputs a low level signal and transmits the low level signal to the or gate 43'. The bidirectional channel is arranged between the TypeC interface H2' and the USB Switch 31', between the USB Switch 31' and the lightning controller 32', and between the USB Switch 31' and the CPU 20, and the input and output (Tx & Rx) can be performed by using the TypeC technology. The lightning controller 32' may be in bi-directional communication with the CPU 20 using a high-speed serial computer expansion bus (PERIPHERAL COMPONENT INTERCONNECT EXPRESS, PCIe).

After the electronic device 101 is externally connected with the display card device 102, a user may perform a function selection operation on the OS of the electronic device 101, so that the electronic device 101 allows the display card device 102 to drive the display screen 10A. For example, as shown in fig. 6 above, after the user clicks the ok button 61 on the reminder pop 60, the display card device 102 may drive the display screen 10A of the electronic device 101.

Illustratively, when the user clicks the ok button 61 on the reminder pop 60, the OS of the electronic device 101 may transmit a first instruction to the CPU 20 of the electronic device 101. After receiving the first instruction, the CPU 20 transmits a second signal to the EC 41'. When the EC 41 'receives the second signal, the EC 41' transmits a low level signal to the or gate 43 'and transmits a first control signal to the USB Switch 31'. The two input terminals of the or gate 43' receive the low level signals transmitted from the EC 41' and the PD 42', and then output the low level signals, i.e., the second control signal. After the USB Switch 31 'receives the first control signal, a connection channel with the lightning controller 32' is opened, and at this time, data can be transmitted between the USB Switch 31 'and the lightning controller 32'. The CPU 20 may transmit the graphics data to the lightning controller 32' through the PCIe channel, then the lightning controller 32' transmits the graphics data to the GPU 31 of the graphics card device 102 through the USB Switch 31', the TypeC interface H2', and the TypeC interface H1', the GPU 31 performs rendering processing on the graphics data to obtain a gpu_edp signal, that is, a first display signal, and then the lightning controller 32' transmits the first display signal to the EDP SWITCH ' through the TypeC interface H1', the TypeC interface H2', the USB Switch 31', and the lightning controller 32 '. EDP SWITCH 50' respectively receives the low level signal and the gpu_edp signal, and then outputs the gpu_edp signal in response to the low level signal. The GPU_eDP signal is transmitted to the display screen 10A through the eDP interface H3 'and the eDP interface H4'. After receiving the gpu_edp signal, the display screen 10A displays based on the gpu_edp signal.

In the embodiment described in fig. 9A, the gpu_edp signal does not pass through the CPU 20 in the process of being transmitted from the graphics card device 102 to the display screen 10A, and the graphics card device 102 can directly drive the display screen 10A without being limited by the performance of the CPU 20, so that the GPU performance of the graphics card device 102 can be fully exerted, and the high performance scene requirement of the user can be met.

In some embodiments, in a low power consumption scenario, as shown in fig. 9B, when the electronic device 101 is not externally connected to the graphics card device 102, since the EC 41 'does not receive the second signal transmitted by the CPU 20, the EC 41' transmits the fourth control signal to the USB Switch 31', and transmits the high level signal to the or gate 43'. Since the PD 42' does not receive the first signal transmitted by the graphic card device 102, the PD 42' transmits a high level signal to the or gate 43 '. The two input terminals of the or gate 43' receive the high level signals transmitted from the EC 41' and the PD 42', and then output the high level signals, i.e., the third control signal. EDP SWITCH 50' respectively receives the high level signal and the cpu_edp signal (i.e., the second display signal) transmitted by the CPU 20, and outputs the cpu_edp signal in response to the high level signal. The cpu_edp signal is transmitted to the display screen 10A through the eDP interface H3 'and the eDP interface H4'. After receiving the cpu_edp signal, the display screen 10A displays based on the cpu_edp signal.

In the embodiment described in fig. 9B, when the electronic device 101 is not externally connected with the display card device 102, the CPU 20 directly drives the display screen 10A, and the power consumption of the GPU 21 integrated inside the CPU 20 is low, so that the low power consumption scene requirement of the user can be met.

In some embodiments, in a low power scenario, referring to fig. 9C, the electronic device 101 may also be external to the input device 103. The input device 103 includes a TypeC interface H5'. The TypeC interface H5 'of the input device 103 is connected to the TypeC interface H2' of the electronic device 101. In the embodiment of the present application, the input device 103 may be a data storage device such as a usb disk, a mobile hard disk, or a device for inputting instructions such as a mouse, a keyboard, etc., which is not limited in any way. The input device 103 is used to input first data to the CPU 20 of the electronic device 101. The first data may be data such as pictures, text, audio, video, etc., or packaged data of a mouse event, or other types of data, which is not limited in any way.

As shown in fig. 9C, when the device externally connected to the electronic device 101 is not the graphics card device 102 but the input device 103, the EC 41 'transmits a fourth control signal to the USB Switch 31' by default, and the USB Switch 31 'closes the connection channel with the lightning controller 32' in response to the fourth control signal. At this time, the input device 103 may transmit the first data to the CPU 20 through the TypeC interface H5', the TypeC interface H2', and the USB Switch 31', and the CPU 20 performs certain processing on the first data, for example, modifies the first data, and the like. At this time, the display screen 10A is still driven by the CPU 20 to display.

In the embodiment described in fig. 9C, when the electronic device 101 is externally connected to the input device 103, the input device 103 may transmit its own data to the CPU 20 of the electronic device 101 through the TypeC interface H5', the TypeC interface H2', and the USB Switch 31 '. That is, the electronic device 101 may read data of the input device 103. Therefore, the requirements of users for external USB flash disk, mobile hard disk, mouse, keyboard and other input devices can be met.

It will be appreciated that in the embodiments illustrated in fig. 9A-9C, the USB Switch 31' may perform channel switching. The channel between the USB Switch 31 'and the lightning controller 32' is closed in the default state. Thus, when the electronic device 101 is connected to the input device 103, the CPU 20 of the electronic device 101 can read the data of the input device 103 normally. When the USB Switch 31 'receives the first control signal transmitted by the EC 41', the USB Switch 31 'opens a channel with the lightning controller 32'. At this time, the CPU 20 may transmit the graphics data to the lightning controller 32 'through the PCIe channel, and the graphics data may be transmitted to the graphics card device 102 by the lightning controller 32'. After receiving the graphics data, the graphics card device 102 renders the graphics data to obtain a gpu_edp signal, and returns the gpu_edp signal to the lightning controller 32' in the form of a lightning signal. The lightning signal may be mixed with a gpu_edp signal and a data signal, and the lightning controller 32 'may separate the gpu_edp signal from the data signal and transmit the data signal to the CPU 20, so that communication interaction between the graphics card device 102 and the CPU 20 may be performed, and the gpu_edp signal may be transmitted to EDP SWITCH'. EDP SWITCH 50 'upon receiving the low level signal output from the or gate 43', outputs a gpu_edp signal in response to the low level signal, and drives the display 10A by the gpu_edp signal.

In other embodiments, the signal transmission circuit 300A according to the present application may be disposed at a location other than the main board 10B of the electronic device 101, for example, a sub-board, etc., which is not limited in any way.

In this embodiment, the graphics card device 102 may be a graphics card box, or may be another device integrated with a GPU. The display card box is integrated with a PCIe slot, a display card power supply system, a lightning 3/4 protocol controller, a TypeC interface and the like. The PCIe slot supports the insertion of the display card, and the display card power supply system can supply power for the display card inserted into the display card box. The lightning 3/4 protocol controller is used for providing communication capability for the typeC interface.

Applications of the electronic device 101 to the GPU include a set display mode, a mixed mode, and a single display mode.

The integrated display mode is to integrate a GPU inside a CPU and drive a display screen through the GPU inside the CPU. The mode has lower power consumption and is suitable for a low-power consumption scene.

The mixed mode is to add an independent GPU on the basis of the integrated display mode. The CPU transmits the graphic data to an independent GPU for rendering to obtain a display signal, then the GPU returns the display signal to the CPU, and the CPU transmits the display signal to a display screen for display. The performance of this mode is Yu Ji apparent modes, but is limited by the performance of the CPU, making it difficult to fully exploit the performance of the GPU.

The single display mode is to add an independent GPU on the basis of the integrated display mode. The CPU transmits the graphic data to an independent GPU for rendering to obtain a display signal, and then the GPU directly transmits the display signal to a display screen for display. The mode can fully exert the performance of the GPU, but has higher power consumption, and consumes more power in non-game scenes and the like, and a single display mode is generally used by a game book.

When a user uses a notebook computer in a set display mode, a display card box is externally connected in order to improve the GPU performance in high-performance scenes such as games. However, after the display card box is externally connected, the display signal generated by the display card box passes through the CPU of the notebook computer, and the CPU transmits the display signal to the display screen for display, which is equivalent to a mixed mode, so that the GPU performance of the display card box is difficult to fully develop. For the notebook computer with the signal transmission circuit provided by the embodiment of the application, when a user connects the notebook computer with the display card box, the USB Switch in the signal transmission circuit can Switch channels so as to bypass the CPU and directly connect the display card box with the display screen, so that the display signal generated by the display card box can be directly transmitted to the display screen without passing through the CPU, thus being not limited by the performance of the CPU, reducing the performance loss, fully playing the GPU performance of the display card box and improving the user experience.

In the drawings, some structural or methodological features may be shown in a particular arrangement and/or order. However, it should be understood that such a particular arrangement and/or ordering may not be required. Rather, in some embodiments, these features may be arranged in a different manner and/or order than shown in the illustrative figures. Additionally, the inclusion of structural or methodological features in a particular figure is not meant to imply that such features are required in all embodiments, and in some embodiments, may not be included or may be combined with other features.

It should be noted that, in the embodiments of the present application, each unit/module mentioned in each device is a logic unit/module, and in physical terms, one logic unit/module may be one physical unit/module, or may be a part of one physical unit/module, or may be implemented by a combination of multiple physical units/modules, where the physical implementation manner of the logic unit/module itself is not the most important, and the combination of functions implemented by the logic unit/module is only a key for solving the technical problem posed by the present application. Furthermore, in order to highlight the innovative part of the present application, the above-described device embodiments of the present application do not introduce units/modules that are less closely related to solving the technical problems posed by the present application, which does not indicate that the above-described device embodiments do not have other units/modules.

It should be noted that in the examples and descriptions of this patent, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

While the application has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the application.

Claims

1. An electronic device is characterized by comprising a display screen, a signal transmission circuit and a first processor;

the signal transmission circuit is connected with the display screen and the first processor, and

The signal transmission circuit is used for transmitting a first display signal of the external display card device to the display screen under the condition that the electronic device is connected with the external display card device, and transmitting a second display signal of the first processor to the display screen under the condition that the electronic device is not externally connected with the display card device;

Wherein the signal transmission circuit includes: the control part is connected with the input part and the output part respectively, and the output part is connected with the input part and is used for controlling the input part to receive the first display signal output by the display card device and transmitting the first display signal to the display screen through the output part under the condition that the electronic device is externally connected with the display card device;

the control part is further used for transmitting a first control signal to the input part and transmitting a second control signal to the output part under the condition that a first signal output by the display card device and a second signal output by the first processor are received;

The input part is used for receiving the first display signal output by the display card device and transmitting the first display signal to the output part under the condition of receiving the first control signal;

The output part is used for transmitting the first display signal to the display screen under the condition that the second control signal is received;

The first signal is output when the display card device is connected with the electronic device; the second signal is output by the first processor when the first operation is received by the electronic device, and the first operation is used for opening the using function of the display card device in the operating system of the electronic device;

Wherein the control part comprises a level shifter, a first controller and a gate circuit, a first input end of the gate circuit is connected with the level shifter, a second input end of the gate circuit is connected with the first controller,

The level shifter is used for transmitting a low-level signal to the first input end of the gate circuit under the condition that the first signal transmitted by the display card device is received;

the first controller is used for transmitting a low-level signal to the second input end of the gate circuit under the condition that the second signal transmitted by the first processor is received;

The gate circuit is used for transmitting a second control signal to the output part when the first input end and the second input end are both input with low-level signals.

2. The electronic device of claim 1, wherein the electronic device comprises a memory device,

The control part is also used for controlling the output part to transmit the second display signal output by the first processor to the display screen under the condition that the electronic equipment is not externally connected with display card equipment.

3. The electronic device of claim 2, wherein the electronic device comprises a memory device,

The control part is further used for transmitting a third control signal to the output part under the condition that the first signal and/or the second signal are not received;

and the output part transmits the second display signal output by the first processor to the display screen under the condition that the third control signal is received.

4. The electronic device of claim 3, wherein the electronic device comprises a plurality of electronic devices,

The control part is further used for transmitting a fourth control signal to the input part under the condition that the second signal is not received;

5. The electronic device of any one of claim 2 to 4, wherein,

The level shifter is used for transmitting a high-level signal to the first input end of the gate circuit under the condition that the first signal is not received;

The first controller is used for transmitting a high-level signal to the second input end of the gate circuit under the condition that the second signal is not received;

The gate circuit is used for transmitting a third control signal to the output part when the first input end and/or the second input end inputs a high-level signal.

6. The electronic device of claim 5, wherein the electronic device comprises a memory device,

The first controller is further configured to output a fourth control signal if the second signal is not received.

7. The electronic device according to any one of claims 2 to 4, wherein the input portion includes a selector and a second controller, the selector being connected to the second controller;

8. The electronic device of claim 7, wherein the electronic device comprises a memory device,

The selector is further configured to receive a fourth control signal output by the first controller and first data output by the input device, and transmit the first data output by the input device to the first processor when the fourth control signal is received.

9. A signal transmission circuit, characterized in that it is provided in an electronic device, said circuit comprising: an input portion, a control portion and an output portion, wherein the control portion is respectively connected with the input portion and the output portion, the output portion is connected with the input portion,

The control part is used for controlling the input part to receive a first display signal output by the display card device and transmitting the first display signal to a display screen of the electronic device through the output part under the condition that the electronic device is externally connected with the display card device, and

The control part is also used for controlling the output part to transmit a second display signal output by the first processor of the electronic equipment to a display screen of the electronic equipment under the condition that the electronic equipment is not externally connected with display card equipment;

10. The circuit of claim 9, wherein the circuit further comprises a logic circuit,

11. The circuit according to claim 9 or 10, wherein,

12. The circuit of claim 9 or 10, wherein the input comprises a selector and a second controller, the selector being connected to the second controller;

13. A motherboard comprising the circuit of any one of claims 9-12.