Detection circuit and detection method of external display device

Abstract

A detection circuit of an external display device includes a first connector, a display circuit, a switch circuit, a power supply circuit, and a control circuit. The display circuit is configured to provide a display signal to the external display device via the first connector. The power supply circuit is configured to provide power required for the display circuit to operate via the switch circuit when the switch circuit is turned on. The control circuit is configured to turn on the switch circuit to turn on the power supply circuit and the display circuit when the external display device is detected. After the switch circuit is turned on, the control circuit is configured to accumulate a duration of continuous time during which the external display device is not detected or a number of times of detection, and turn off the switch circuit to turn off the power supply circuit and the display circuit when the duration of continuous time reaches a time threshold or the number of times of detection reaches a number threshold.

Description

TECHNICAL FIELD

[0001] The present application relates to intelligent start-up technology, and in particular, to a detection circuit and a detection method for an external display device. BACKGROUND

[0002] Generally, when a mobile device is in standby and not in use, idle power consumption will be generated on a display circuit used to output a display signal to an external display device. The idle power consumption will affect the endurance of the mobile device and also affect the battery life of the mobile device. In order to prevent the generation of idle power consumption, conventionally, the mobile device switches the display circuit on and off by detecting the connection status of the external display device and the mobile device through a system. The system turns on the display circuit when the connection between the external display device and the mobile device is detected, and turns off the display circuit when the connection between the external display device and the mobile device is broken.

[0003] However, if the external display device is frequently plugged in and unplugged within a short period of time, the system will frequently enable the display circuit by detecting the connection status of the external display device and the mobile device, and thus the system will be busy, which will affect the user experience. SUMMARY

[0004] In an embodiment, a detection circuit for an external display device includes a first connector, a display circuit, a switch circuit, a power supply circuit, and a control circuit. The display circuit is coupled to the first connector and is configured to provide a display signal to the external display device via the first connector. The switch circuit is coupled to the display circuit. The power supply circuit is coupled to the switch circuit and is configured to provide power required for the operation of the display circuit via the switch circuit when the switch circuit is turned on. The control circuit is coupled to the first connector and the switch circuit and is configured to detect the external display device via the first connector and selectively switch the switch circuit according to the detection result of the external display device. When the external display device is detected, the control circuit turns on the switch circuit to turn on the power supply circuit and the display circuit, and after the switch circuit is turned on, the control circuit is further configured to accumulate the duration of continuous non-detection of the external display device or the number of detections, and turn off the switch circuit to turn off the power supply circuit and the display circuit when the duration reaches a time threshold or the number of detections reaches a number threshold.

[0005] In an embodiment, a detection method for an external display device includes repeatedly detecting the external display device, turning on a power supply path of a display circuit and supplying power to the display circuit via the power supply path when the external display device is detected, accumulating the duration of continuous non-detection of the external display device or the number of detections in a state where the power supply path is turned on, or turning off the power supply path when the duration reaches a time threshold or the number of detections reaches a number threshold.

[0006] In summary, the detection circuit of the external display device and the detection method of the external display device of any embodiment can turn on the power supply path of the display circuit when the external display device is detected, and turn off the power supply path when the external display device is disconnected for a period of time (i.e. the duration of the external display device is not detected or the detection frequency reaches a predetermined threshold), thereby avoiding idle power consumption, and avoiding frequent enabling of the display circuit, thereby achieving the effect of saving power without affecting the user experience.

[0007] The present application is described in detail below with reference to the accompanying drawings and specific embodiments, but is not limited thereto. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 Block diagram of an embodiment of the detection circuit of the external display device.

[0009] Figure 2 Flowchart of an embodiment of the detection method of the external display device.

[0010] Figure 3 Block diagram of another embodiment of the detection circuit of the external display device.

[0011] Figure 4 Block diagram of another embodiment of the detection circuit of the external display device.

[0012] Figure 5 Block diagram of another embodiment of the detection method of the external display device.

[0013] Figure 6 Block diagram of another embodiment of the detection method of the external display device. Figure 4 Circuit diagram of an embodiment of the potential conversion circuit of the detection circuit of the external display device.

[0014] Figure 7 Circuit diagram of another embodiment of the potential conversion circuit of the detection circuit of the external display device. Figure 1 Voltage timing diagram of the display circuit of the detection circuit of the external display device during operation.

[0015] Wherein, the reference numeral

[0016] 10: detection circuit

[0017] 110: first connector

[0018] 120: display circuit

[0019] 130: switch circuit

[0020] 140: power supply circuit

[0021] 150: control circuit

[0022] 20: external display device

[0023] S1: insertion signal

[0024] S2: display signal

[0025] S01-S04: steps

[0026] 1101: detection pin

[0027] 1102: signal pin

[0028] 1301: power switch

[0029] 160: second connector

[0030] 170: potential conversion circuit

[0031] S3: display signal

[0032] IN: input end

[0033] OUT: output end

[0034] VDD: voltage source

[0035] GND: ground end

[0036] T0: time point

[0037] T1: time point

[0038] T2: time point

[0039] T3: time point

[0040] T4: time point

[0041] T5: time point

[0042] T6: time point

[0043] P1: time interval

[0044] P2: time interval

[0045] P3: time interval

[0046] On: on voltage

[0047] Off: off voltage DETAILED DESCRIPTION

[0048] The structural principle and working principle of the present application will be described in detail below in combination with the drawings:

[0049] Figure 1 The block schematic diagram of an embodiment of the detection circuit 10 of the external display device 20. Please refer to Figure 1The detection circuit 10 includes a connector (hereinafter referred to as a first connector 110), a display circuit 120, a switch circuit 130, a power supply circuit 140, and a control circuit 150. The first connector 110 is coupled to the display circuit 120, the control circuit 150, and an external display device 20. The switch circuit 130 is coupled to the display circuit 120, the power supply circuit 140, and the control circuit 150.

[0050] The first connector 110 is used to electrically connect with the external display device 20, so that the internal circuits of the detection circuit 10 can transmit signals to the external display device 20 via the first connector 110. In some embodiments, the external display device 20 can be, but is not limited to, a VGA device, a DisplayPort device, or an HDMI device, and the first connector 110 corresponding to the external display device 20 can be, but is not limited to, a VGA interface connector, a DisplayPort interface connector, or an HDMI interface connector.

[0051] The display circuit 120 is used to provide a display signal S2 to the external display device 20 via the first connector 110. Moreover, the external display device 20 will display a picture according to the received display signal S2 when receiving the display signal S2. In some embodiments, the display signal S2 is the display content mapped from a host (not shown in the figure) to the display circuit 120. In other words, the signal source of the display signal S2 provided by the display circuit 120 to the external display device 20 via the first connector 110 is a graphic processor (GPU) inside the host. In some embodiments, the host can be, but is not limited to, a personal computer (PC), a notebook computer, or a tablet computer. In some embodiments, the display circuit 120 can be, but is not limited to, a display integrated circuit (IC). In an exemplary embodiment, the display circuit 120 can be, but is not limited to, an embedded circuit inside the host, that is, the detection circuit 10 can be built inside the host. In another exemplary embodiment, the display circuit 120 can be, but is not limited to, a circuit inside a conversion device connected with the host, that is, the detection circuit 10 can be an external device of the host, that is, a conversion device connected with the host by another connector (hereinafter referred to as a second connector 160, as shown in the figure). The conversion device can be, but is not limited to, an image adapter or an adapter cable, etc. Figure 3

[0052] The switch circuit 130 is controlled by the control circuit 150 and is used to turn on or turn off the power supply path between the power supply circuit 140 and the display circuit 120. When the switch circuit 130 is turned on, the power supply circuit 140 and the display circuit 120 are turned on; at this time, the power supply circuit 140 provides the power required for the display circuit 120 to operate. When the switch circuit 130 is turned off, the connection between the power supply circuit 140 and the display circuit 120 is disconnected; at this time, the power supply circuit 140 stops supplying power to the display circuit 120. ​

[0053] In other words, the power supply circuit 140 is configured to provide the power required by the display circuit 120 via the switch circuit 130 when the switch circuit 130 is turned on.

[0054] The control circuit 150 is configured to detect the external display device 20 via the first connector 110, and selectively turn on the switch circuit 130 to enable the display circuit 120 according to the detection result of the external display device 20.

[0055] Figure 2 A flowchart of an embodiment of the detection method of the external display device 20. Please refer to Figure 1 and Figure 2 In some embodiments, the control circuit 150 repeatedly detects the insertion signal S1 from the external display device 20 via the first connector 110 (step S01) to determine whether the external display device 20 is detected according to whether the insertion signal S1 is received. Wherein, when the control circuit 150 receives the insertion signal S1, it indicates that the control circuit 150 detects the external display device 20; otherwise, when the insertion signal S1 is not received, it indicates that the external display device 20 is not detected.

[0056] When the control circuit 150 detects the external display device 20, the control circuit 150 turns on the switch circuit 130 to connect the power supply circuit 140 and the display circuit 120. At this time, the power supply circuit 140 provides power required for the display circuit 120 to operate to enable the display circuit 120 (step S02). After turning on the switch circuit 130, the control circuit 150 continues to detect the external display device 20 repeatedly via the first connector 110. When the external display device 20 is not detected, the control circuit 150 accumulates the duration (or the number of detections) of continuous non-detection of the external display device 20 (step S03). When the duration reaches a time threshold (or the number of detections reaches a number threshold), the control circuit 150 turns off the switch circuit 130 to disconnect the power supply circuit 140 and the display circuit 120 (step S04). For example, taking the time threshold as an example, assuming that the time threshold is 10 seconds (but not limited to this), and the control circuit 150 detects the external display device 20 for 20 times within 10 seconds. After turning on the switch circuit 130, the control circuit 150 detects the external display device 20 at a frequency of 2 times per second, and starts the duration when the external display device 20 is not detected, and stops and resets the duration when the external display device 20 is detected. When the external display device 20 is not detected within 10 seconds, the duration counted by the control circuit 150 reaches 10 seconds; at this time, the control circuit 150 turns off the switch circuit 130. Conversely, as long as the counted duration does not reach 10 seconds, the control circuit 150 does not turn off the switch circuit 130, that is, the switch circuit 130 remains on to connect the power supply circuit 140 and the display circuit 120. In another example, taking the number threshold as an example, assuming that the number threshold is 20 times (but not limited to this), and the control circuit 150 detects the external display device 20 for 20 times within 10 seconds. After turning on the switch circuit 130, the control circuit 150 detects the external display device 20 at a frequency of 2 times per second, and accumulates the number of detections when the external display device 20 is not detected, and resets the number of detections when the external display device 20 is detected. When the external display device 20 is not detected for 20 consecutive times, the number of detections accumulated by the control circuit 150 reaches 20 times; at this time, the control circuit 150 turns off the switch circuit 130. Conversely, as long as the accumulated number of detections does not reach 20 times, the control circuit 150 does not turn off the switch circuit 130, that is, the switch circuit 130 remains on to connect the power supply circuit 140 and the display circuit 120. In some embodiments, the control circuit 150 can be, but is not limited to, a microcontroller unit (MCU) or an embedded controller (EC).

[0057] Figure 3 Block diagram of another embodiment of the detection circuit 10 for the external display device 20. Please refer to Figure 1 andFigure 3 In some embodiments, the detection circuit 10 can further include a second connector 160. The second connector 160 is coupled to the display circuit 120. The detection circuit 10 can be coupled to a host (not shown) via the second connector 160. When the power circuit 140 is powered, the display circuit 120 receives a display signal S3 from the host via the second connector 160. The display signal S3 is of a first signal specification. The display circuit 120 decodes the display signal S3 to convert the display signal S3 to a display signal S2 of a second signal specification, and outputs the display signal S2 of the second signal specification to the external display device 20 via the first connector 110. The first signal specification corresponds to an interface specification of the second connector 160, and the second signal specification corresponds to an interface specification of the first connector 110. For example, the second connector 160 is a USB interface connector (but not limited thereto), and the first connector 110 is an HDMI interface connector (but not limited thereto); in this case, the first signal specification is a USB signal, and the second signal specification is an HDMI signal. In other words, the detection circuit 10 is a USB-to-HDMI conversion circuit. When powered, the display circuit 120 receives a USB signal (i.e., the display signal S3) from the host via the second connector 160, converts the received USB signal to an HDMI signal (i.e., the converted display signal S2), and outputs the HDMI signal to the first connector 110. In some embodiments, the first connector 110 and the second connector 160 can be connectors of different two interface specifications (i.e., corresponding to the first signal specification and the second signal specification, respectively). The interface specifications can be USB interface, HDMI interface, DisplayPort interface, VGA interface, or SD interface, etc.

[0058] In some embodiments, the first connector 110 includes a detection pin 1101 and at least one signal pin 1102. The detection pin 1101 is coupled to the control circuit 150, and is used to output the insertion signal S1 from the external display device 20 to the control circuit 150. Here, the control circuit 150 repeatedly detects the insertion signal S1 from the external display device 20 via the detection pin 1101. The signal pin 1102 is coupled to the display circuit 120, and is used to output the display signal S2 provided by the display circuit 120 to the external display device 20.

[0059] In some embodiments, the switch circuit 130 further comprises a power switch 1301. The power switch 1301 is coupled between the display circuit 120 and the power supply circuit 140 and is controlled by the control circuit 150. The control circuit 150 generates a turn-on signal to the power switch 1301 to turn on the power switch 1301 to turn on the switch circuit 130. When the switch circuit 130 is turned on, the power supply circuit 140 and the display circuit 120 are turned on to each other via the power switch 1301, so that the power supply circuit 140 can provide the power required for the display circuit 120 to operate to the display circuit 120 via the power switch 1301. The control circuit 150 generates a turn-off signal to the power switch 1301 to turn off the power switch 1301 to turn off the switch circuit 130. When the switch circuit 130 is turned off, the connection between the power supply circuit 140 and the display circuit 120 (i.e. the power switch 1301 coupled therebetween) is disconnected, so that the power supply circuit 140 stops supplying power to the display circuit 120. In some embodiments, the turn-on signal and the turn-off signal can be high level signal and low level signal respectively. In some embodiments, the power switch 1301 can be a transistor. In which, the first end and the second end of the transistor are connected to the power supply circuit 140 and the display circuit 120 respectively, and the control end of the transistor is connected to the control circuit 150.

[0060] Figure 4 A block diagram of another embodiment of the detection circuit 10 for the external display device 20. Please refer to Figure 1 and Figure 4 In some embodiments, the detection circuit 10 further comprises a potential conversion circuit 170. The potential conversion circuit 170 is coupled between the first connector 110 and the control circuit 150. The potential conversion circuit 170 is used to convert the voltage of the insertion signal S1 from the external display device 20 to the voltage suitable for the control circuit 150. For example, the voltage of the insertion signal S1 is 5V, and the voltage suitable for the control circuit 150 is 3.3V, at this time the potential conversion circuit 170 converts the voltage of the insertion signal S1 from 5V to 3.3V. In some embodiments, the potential conversion circuit 170 converts the insertion signal S1 from the external display device 20 from high voltage to low voltage (for example, converts the voltage of the insertion signal S1 from 5V to 3.3V) or converts the insertion signal S1 from the external display device 20 from low voltage to high voltage (for example, converts the voltage of the insertion signal S1 from 3.3V to 5V), but the present application is not limited thereto.

[0061] Figure 5 A block diagram of another embodiment of the detection method for the external display device 20. Please refer to Figure 1 and Figure 5In some embodiments, the first connector 110 is electrically connected to the plurality of external display devices 20, such that the internal circuit of the detection circuit 10 can transmit signals to the plurality of external display devices 20 via the first connector 110.

[0062] The control circuit 150 repeatedly detects the insertion signal S1 from the plurality of external display devices 20 via the first connector 110, to determine whether at least one external display device 20 is detected according to whether the insertion signal S1 is received. When the control circuit 150 receives the insertion signal S1, it indicates that the control circuit 150 detects at least one external display device 20; otherwise, when the insertion signal S1 is not received, it indicates that no external display device 20 is detected.

[0063] When the control circuit 150 detects at least one external display device 20, the control circuit 150 turns on the switching circuit 130 to turn on the power supply circuit 140 and the display circuit 120. At this time, the power supply circuit 140 provides power required for the display circuit 120 to operate so as to enable the display circuit 120. After turning on the switching circuit 130, the control circuit 150 continues to repeatedly detect the external display device 20 via the first connector 110. When no external display device 20 is detected, the control circuit 150 accumulates the duration (or the number of detections) of continuous time during which no external display device 20 is detected. When the duration reaches a time threshold (or the number of detections reaches a number threshold), the control circuit 150 turns off the switching circuit 130 to disconnect the power supply circuit 140 and the display circuit 120.

[0064] Figure 6 For Figure 4 A circuit diagram of an embodiment of the potential conversion circuit 170 of the detection circuit 10 of the external display device 20. In Figure 6 , IN is the input terminal, OUT is the output terminal, VDD is the voltage source, and GND is the ground terminal. The input terminal IN is coupled to the first connector 110 (not shown in the figure), and the output terminal OUT is coupled to the control circuit 150 (not shown in the figure).

[0065] Figure 7 For Figure 1 A voltage timing diagram of the display circuit 120 of the detection circuit 10 of the external display device 20 during operation. In Figure 7 , On is the turn-on voltage of the display circuit 120, and Off is the turn-off voltage of the display circuit 120.

[0066] Please refer to Figure 1 and Figure 7At time point T0 to time point T6, the control circuit 150 repeatedly detects the insertion signal S1 from the external display device 20 via the first connector 110. Before time point T1, the power supply of the display circuit 120 remains off because the insertion signal S1 is not received, thereby saving power. In other words, the display circuit 120 does not consume power before the external display device 20 is inserted.

[0067] At time point T1, the external display device 20 is inserted into the first connector 110. At time point T1 to time point T2, the control circuit 150 receives the insertion signal S1 from the external display device 20 and outputs an enabling signal to the switch circuit 130, so that at time point T2, the switch circuit 130 is turned on in response to the enabling signal, and thus the power supply circuit 140 starts to supply power to the display circuit 120 via the switch circuit 130. The time interval P1 required for the control circuit 150 to receive the insertion signal S1 to turn on the switch circuit 130 is the time interval from the time point T1 when the external display device 20 is inserted to the time point T2 when the display circuit 120 starts to be powered.

[0068] At time point T2, the switch circuit 130 is turned on in response to the enabling signal, and the power supply circuit 140 starts to supply power to the display circuit 120 via the switch circuit 130. At time point T3, the power supply circuit 140 completes the power supply to the display circuit 120 to enable the display circuit 120, and the display circuit 120 starts to provide the display signal S2 to the external display device 20 via the first connector 110, so that the external display device 20 displays a picture according to the received display signal S2. The time interval P2 required for the control circuit 150 to turn on the switch circuit 130 to enable the display circuit 120 is the time interval from the time point T2 when the power supply circuit 140 starts to supply power to the display circuit 120 via the switch circuit 130 to the time point T3 when the power supply circuit 140 completes the power supply to the display circuit 120. In some embodiments, the time interval P2 can be, but is not limited to, 5 seconds.

[0069] At time point T4, the external display device 20 is unplugged from the first connector 110, so that the control circuit 150 starts not receiving the insertion signal S1, but the control circuit 150 does not immediately cut off the power supply of the display circuit 120, but starts accumulating the duration (or the number of detections) of continuously not detecting the external display device 20. At time point T5, the duration reaches a time threshold (or the number of detections reaches a number threshold); at this time, the control circuit 150 only closes the switch circuit 130 to cut off the power supply of the display circuit 120. The time required for the duration to reach the time threshold (or the number of detections to reach the number threshold) is the time interval P3 from the time point T4 when the external display device 20 is unplugged to the time point T5 when the display circuit 120 is closed. For example, the time threshold is 10 seconds, and the time interval P3 from the time point T4 when the external display device 20 is unplugged to the time point T5 when the display circuit 120 is closed is 10 seconds.

[0070] In this way, when the external display device 20 is unplugged, the control circuit 150 does not immediately cut off the power supply of the display circuit 120, but after multiple confirmations, i.e., when the duration of the continuous non-detection of the external display device 20 reaches a time threshold (or the number of detections of the external display device 20 reaches a number threshold), the switch circuit 130 is closed to disconnect the power supply circuit 140 and the display circuit 120. In this way, the power supply of the display circuit 120 can be prevented from being cut off in the case of unplugging of the external display device 20 that is not intended by the user, i.e., the user experience can be improved when the external display device 20 is unplugged and then quickly plugged back in, because the display circuit 120 does not need to be re-enabled. The unplugging that is not intended by the user can be, for example, a short unplugging of the external display device 20 caused by human collision or poor line contact. For example, if the time threshold is 10 seconds (or the number threshold is 20 times), when the user unintentionally collides with the external display device 20 and causes it to be disconnected from the detection circuit 10, the user has 10 seconds (or 20 detections) to plug the external display device 20 back in. If the external display device 20 is plugged back in within 10 seconds (or 20 detections), the display circuit 120 has not been closed at this time, and the control circuit 150 does not need to turn on the switch circuit 130 again to turn on the power supply circuit 140 and the display circuit 120, and the control circuit 150 does not need to enable the display circuit 120 again. Therefore, the total time of the time interval P1 from the time point T1 at which the external display device 20 is plugged in to the time point T2 at which the display circuit 120 starts to supply power, and the time interval P2 from the time point T2 at which the display circuit 120 starts to supply power to the time point T3 at which the external display device 20 displays a picture can be saved. In other words, the user does not need to wait for the total time of the time interval P1 from the time point T1 at which the external display device 20 is plugged in to the time point T2 at which the display circuit 120 starts to supply power, and the time interval P2 from the time point T2 at which the display circuit 120 starts to supply power to the time point T3 at which the external display device 20 displays a picture every time the external display device 20 is unintentionally disconnected, thereby improving the user experience. In some embodiments, the total time of the time interval P1 from the time point T1 at which the external display device 20 is plugged in to the time point T2 at which the display circuit 120 starts to supply power, and the time interval P2 from the time point T2 at which the display circuit 120 starts to supply power to the time point T3 at which the external display device 20 displays a picture can be, but is not limited to, 5 seconds.

[0071] In summary, the detection circuit 10 of the external display device 20 and the detection method of the external display device 20 of any embodiment can turn on the power supply path of the display circuit 120 only when the external display device 20 is detected, and turn off the power supply path only when the external display device 20 is disconnected for a period of time (i.e. the duration of the external display device 20 is not detected or the detection frequency reaches a predetermined threshold). In this way, idle power consumption is avoided, and the system is not frequently enabled to display the circuit 120, thereby achieving the effect of saving power without affecting the user experience.

[0072] Of course, the present application can have other various embodiments, and those skilled in the art can make various corresponding changes and modifications according to the present application without departing from the spirit and essence of the present application. However, these corresponding changes and modifications should all belong to the protection scope of the claims attached to the present application.

Claims

1. A detection circuit for an external display device, characterized in that, Include: First connector; A display circuit, coupled to the first connector, is used to provide a display signal to an external display device via the first connector; A switching circuit is coupled to the display circuit; A power supply circuit, coupled to the switching circuit, is used to provide the power required for the operation of the display circuit through the switching circuit when the switching circuit is turned on; and A control circuit, coupled to the first connector and the switching circuit, is used to detect the external display device via the first connector and selectively switch the switching circuit based on the detection result of the external display device. The control circuit activates the switch circuit when it detects the external display device to connect the power circuit and the display circuit. After activating the switch circuit, the control circuit also accumulates the number of times the external display device is not detected consecutively, and deactivates the switch circuit to disconnect the power circuit and the display circuit when the number of detections reaches a threshold.

2. The detection circuit for the external display device according to claim 1, characterized in that, Also includes: A second connector is coupled to the display circuit, wherein the display circuit receives the display signal from a host via the second connector, converts the display signal from a first signal specification to a second signal specification, and outputs the display signal with the second signal specification to the first connector.

3. The detection circuit for the external display device according to claim 1, characterized in that, The switching circuit includes: A power switch is connected between the display circuit and the power circuit and is controlled by the control circuit.

4. The detection circuit for the external display device according to claim 1, characterized in that, The first connector includes: A detection pin, coupled to the control circuit, is used to output an insertion signal from the external display device to the control circuit; and At least one signal pin is coupled to the display circuit to output the display signal to the external display device.

5. The detection circuit for the external display device according to claim 1, characterized in that, Also includes: A potential conversion circuit is coupled between the first connector and the control circuit.

6. The detection circuit for the external display device according to claim 1, characterized in that, The control circuit is a microcontroller unit (MCU) or an embedded controller (EC).

7. The detection circuit for the external display device according to claim 1, characterized in that, The display circuit is a display chip IC.

8. The detection circuit for the external display device according to claim 1, characterized in that, The external display device can be a VGA device, a DisplayPort device, or an HDMI device.

9. A detection circuit for an external display device, characterized in that, Include: First connector; A display circuit, coupled to the first connector, is used to provide a display signal to a plurality of external display devices via the first connector; A switching circuit is coupled to the display circuit; A power supply circuit, coupled to the switching circuit, is used to provide the power required for the operation of the display circuit through the switching circuit when the switching circuit is turned on; and A control circuit, coupled to the first connector and the switching circuit, is used to detect the external display devices via the first connector and selectively switch the switching circuit based on the detection results of the external display devices; The control circuit activates the switch circuit to conduct the power circuit and the display circuit when at least one of the external display devices is detected. After activating the switch circuit, the control circuit also accumulates a number of consecutive detections of the external display devices, and deactivates the switch circuit to disconnect the power circuit and the display circuit when the number of detections reaches a threshold.

10. A method for detecting an external display device, characterized in that, Include: Repeatedly detect an external display device; When the external display device is detected, a power supply path of a display circuit is turned on and power is supplied to the display circuit through the power supply path; With the power supply path active, the duration and number of consecutive times the external display device is not detected are accumulated; and If the duration reaches a time threshold and the number of detections reaches a single detection threshold, the power supply path is disconnected.

11. The detection method for an external display device according to claim 10, characterized in that, Also includes: After power is supplied to the display circuit via the power supply path, the display circuit outputs a display signal and provides the display signal to the external display device via a first connector.

12. The detection method for an external display device according to claim 11, characterized in that, Also includes: The display signal is received via a second connector.

13. The detection method for an external display device according to claim 12, characterized in that, Also includes: The display circuit is used to convert the signal specifications of the display signal.

14. The detection method for an external display device according to claim 10, characterized in that, The steps to turn on the power supply path of the display circuit include: Turn on a power switch that is coupled between the display circuit and a power supply circuit.

15. The detection method for an external display device according to claim 14, characterized in that, The steps to disconnect the power supply path include: Turn off the power switch.

16. The detection method for an external display device according to claim 10, characterized in that, The steps of repeatedly detecting the external display device include: Repeatedly detect a detection pin of a first connector to confirm whether an insertion signal is received through the detection pin, wherein receiving the insertion signal indicates that the external display device is detected, and not receiving the insertion signal indicates that the external display device is not detected.

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