TWI661729B - Display device with HDMI port supporting POH function - Google Patents

Abstract

A display device includes an HDMI port, a power supply, a microcontroller, a POH switch circuit and a POH correction circuit. The HDMI port supports the POH function. The power supply receives external AC power, outputs standby power in standby mode, and outputs standby and working power in startup mode. The microcontroller performs a software reset by triggering a voltage climb when the standby power is established. The POH switch circuit determines whether to turn on and transmit the standby power to the HDMI port power pin according to the working power source and the hot plug detection signal related to the HDMI port hot plug detection pin. The POH correction circuit determines whether the POH switch circuit is on according to the working power supply. When the display device is coupled to an external device with an external power supply through the HDMI port, even if the display device is disconnected and then reconnected to the AC power for a short time, the machine can still be turned on and off normally.

Description

Display device with HDMI port supporting POH function

The invention relates to a display device with a high definition multimedia interface (High Definition Multimedia Interface, HDMI) port, and in particular to a display device with an HDMI port supporting a function of HDMI on Power (POH).

FIG. 1 is a circuit block diagram of a conventional display device having an HDMI port supporting a POH function. Referring to FIG. 1, a conventional display device 1 includes an HDMI port 11, a power supply 12, a microcontroller 13 and a POH switch circuit 14. The HDMI port 11 has multiple pins. These pins include a power pin 111 and a hot plug detect pin 112. The power supply 12 receives an external AC power source Vac, and outputs a standby power source Vsb in a standby mode, and outputs a standby power source Vsb and a working power source Vop in an on mode. In one embodiment, the standby power source Vsb is a 5V DC power source for supplying power to the microcontroller 13; the working power source Vop is a 19V DC power source for supplying power to, for example, an image processing circuit; in addition, the power supply 12 may output other Working power supplies with different voltage levels are used to supply power to, for example, backlight modules and speaker circuits.

When the display device 1 is connected to the AC power Vac, the power supply 12 receives the AC power Vac and first establishes a standby power Vsb to supply power to the microcontroller 13. The voltage climbing action when the standby power supply Vsb is established triggers the microcontroller 13 to perform a software reset to enter the standby mode. In the standby mode, the microcontroller 13 monitors whether there is a power-on command CMD issued by a user by pressing a power button provided on, for example, a remote controller or a display device casing. When a startup command CMD is monitored, the microcontroller 13 outputs a power-on signal PS_ON to the power supply 12 so that the power supply 12 starts to establish all working power sources (including the working power source Vop) to supply power to the image processing circuit and the backlight module. , Speaker circuit, etc. to enter the boot mode. The microcontroller 13 is coupled to the hot-plug detection pin 112 of the HDMI port 11 and determines whether to output the hot-plug detection signal HPD to the POH switch circuit 14 according to the voltage level of the hot-plug detection pin 112. When the microcontroller 13 monitors that the HDMI port 11 is coupled to an external HDMI port (not shown) according to the voltage level of the hot-plug detection pin 112, the microcontroller 13 outputs a hot-plug detection signal HPD to the POH switch Circuit 14.

FIG. 2 is a circuit diagram of the POH switch circuit 14 shown in FIG. 1. Please refer to FIG. 1 and FIG. 2 at the same time. The POH switching circuit 14 includes a P-channel metal-oxide-semiconductor half-effect transistor Q11 and an N-channel metal-oxide-semiconductor half-effect transistor Q12, and a P-channel metal-oxide-semiconductor half-effect transistor Q11 and an N-channel metal-oxide-semiconductor half-field The effect transistor Q12 has parasitic diodes D11 and D12, respectively. Among them, the source of the P-channel metal-oxide-semiconductor field-effect transistor Q11 is coupled to the power source Vsb, and the gate of the P-channel metal-oxide-semiconductor field-effect transistor Q11 is used to receive the hot-plug detection pin 112 related to the HDMI port 11. Hot-swap detection signal HPD, the drain of the P-channel CMOS half-effect transistor Q11 is coupled to the source of the N-channel CMOS half-effect transistor Q12, and the drain and gate of the N-channel MOSFET half-effect transistor Q12 The power pin 111 and the working power source Vop of the HDMI port 11 are respectively coupled, and the anode and the cathode of the parasitic diode D11 are respectively coupled to the drain and source of the P-channel metal-oxide-semiconductor field-effect transistor Q11 and the parasitic diode D12. The anode and the cathode are respectively coupled to the source and the drain of an N-channel metal-oxide-semiconductor field-effect transistor Q12.

The POH switch circuit 14 also includes resistors R11 to R15, capacitors C11 and C12, and an NPN bipolar transistor Q13 to help the P-channel metal-oxide-semiconductor half-effect transistor Q11 and the N-channel metal-oxide-semiconductor half-effect transistor Q12 work better. . The source of the P-channel metal-oxide-semiconductor half-effect transistor Q11 is coupled to the host power supply Vsb through the resistor R11 and the capacitor C11, and the resistor R11 and the capacitor C11 are used to provide a voltage stabilization filtering function for the standby power supply Vsb. The gate of the P-channel CMOS half-effect transistor Q11 receives the hot-plug detection signal HPD through the resistor R12 and the NPN bipolar transistor Q13. Coupling resistor R13. When the microcontroller 13 monitors that the HDMI port 11 is coupled to an external HDMI port and outputs a hot-plug detection signal HPD, the hot-plug detection signal HPD is a high-level signal and the NPN bipolar transistor Q13 is turned on, and the P channel The gate of the metal oxide half field effect transistor Q11 is equivalent to coupling to ground. The source of the P channel metal oxide half field effect transistor Q11 will be large enough to make the P channel metal oxide half field effect transistor Q11 conductive; otherwise, When the HDMI port 11 is not coupled to the external HDMI port, the hot-plug detection signal HPD is a low-level signal and the NPN bipolar transistor Q13 is not turned on. The source-gate voltage of the P channel metal-oxide-semiconductor half-effect transistor Q11 Because the voltage drop of the resistor R13 is not large enough, the P-channel metal-oxide-semiconductor half field effect transistor Q11 is not turned on.

In addition, the gate of the N-channel metal-oxide-semiconductor field-effect transistor Q12 is coupled to the working power source Vop through a resistor R14 and a capacitor C12, and the resistor R14 and the capacitor C12 are used to provide a voltage filtering function for the working power source Vop. When the working power supply Vop is established (indicating entering the power-on mode), the gate-to-source voltage of the N-channel metal-oxide-semiconductor half-effect transistor Q12 will be large enough to turn on the N-channel metal-oxide-semiconductor half-effect transistor Q12; otherwise, when the working power supply When Vop has not been established (indicating that the AC power Vac is not connected or in standby mode), the gate-to-source voltage of the N-channel metal-oxide-semiconductor half-effect transistor Q12 must not be large enough to make the N-channel metal-oxide-semiconductor half-effect transistor Q12 Not conducting.

Therefore, when the HDMI port 11 of the display device 1 is coupled to the external HDMI port and the working power supply Vop is established and in the boot mode, the P-channel CMOS half-effect transistor Q11 and the N-channel CMOS half-effect transistor Q12 are both turned on, The standby power Vsb can be transmitted to the power pin 111 of the HDMI port 11 through the P-channel metal-oxide-semiconductor Q11 and N-channel metal-oxide-semiconductor Q12; at this time, if the external device (not shown) where the external HDMI port is located ) Without external power supply, the standby power Vsb transmitted to the power pin 111 of the HDMI port 11 can be supplied to external devices through the external HDMI port. Since the display device 1 is coupled to an external device without external power supply through the HDMI port 11, the display device 1 can supply power to the external device, so it is said that the HDMI port 11 supports the POH function. In an embodiment, the display device 1 is a television and has an external AC power supply Vac; the external device is a DVD player and does not have an external power supply; when the display device 1 is coupled to an external device through an HDMI port 11 that supports a POH function In the case of the HDMI port, the display device 1 supplies power to external devices through the HDMI port 11.

However, when the display device 1 is coupled to an external device with an external power supply through the HDMI port 11 with a POH function, the external device will not have a line design that accepts the power of the HDMI port 11 because it has external power supply, so that the standby power supply Vsb It cannot be transmitted to external devices through the power pin 111 of the HDMI port 11; instead, the external device will pass through the N-channel metal-oxide-semiconductor Q12 and parasitic diode of the N-channel metal-oxide-semiconductor field-effect transistor Q12 that are turned on through the power pin 111 of the HDMI port 11 and the POH switch circuit 14 D11 transmits the power to the standby power Vsb of the display device 1. When the display device 1 turns off the AC power supply Vac and then turns on the AC power supply Vac again within a short time, the voltage level of the working power supply Vop is too late to make the N-channel metal-oxide-semiconductor half-effect transistor Q12 non-conductive and the standby power supply Vsb It ’s too late to drop to a level that can trigger the microcontroller 13 to perform a software reset. At this time, the external device has passed through the N-channel metal-oxygen half-field in the power supply pin 111 of the HDMI port 11 and the POH switch circuit 14. The effect transistor Q12 and the parasitic diode D11 transmit power to the standby power source Vsb of the display device 1 to maintain the voltage level of the standby power source Vsb no longer drop. However, since the display device 1 was disconnected from the AC power source Vac first, some software and / or hardware components may malfunction or stop working due to insufficient power supply of the working power source Vop, which should have been passed after the AC power source Vac was reconnected. The voltage climbing action when the standby power supply Vsb is established triggers the microcontroller 13 to perform a software reset so as to re-enter the standby mode and then enter the boot mode normally. However, the microcontroller is not triggered because the external device supplies reverse power to the standby power supply Vsb. 13 Perform a software reset so that the display device 1 does not work properly, and the user cannot switch the display device 1 between the standby mode and the boot mode by pressing the power-on command CMD issued by the power button, that is, the display device 1 cannot be turned on and off normally. machine.

The object of the present invention is to provide a display device with an HDMI port supporting POH function. When the display device is coupled to an external device powered by an external power supply through the HDMI port having POH function, even if the display device is disconnected from the AC for a short time, If the power is turned on again, the display device can still be turned on and off normally.

To achieve the above object, the present invention provides a display device including an HDMI port, a power supply, a microcontroller, a POH switch circuit and a POH correction circuit. The HDMI port supports the POH function. The power supply receives external AC power and outputs standby power in standby mode, and outputs standby power and working power in startup mode. The microcontroller is powered by the standby power, and the software reset is triggered by the voltage climb action when the standby power is established. The POH switching circuit includes a P-channel metal-oxide-semiconductor half-field-effect transistor, an N-channel metal-oxide-semiconductor half-field-effect transistor, and a parasitic diode. The source of the P-channel metal-oxide-semiconductor half-field-effect transistor is coupled to the power supply of the receiver, and the gate of the P-channel metal-oxide-semiconductor half-field-effect transistor is used to receive the hot-plug detection related to the hot-plug detection pin of the HDMI port. Signal, the drain of the P-channel MOSFET is coupled to the source of the N-channel MOSFET, and the drain and gate of the N-channel MOSFET are coupled to the power pin of the HDMI port With the working power source, the anode and cathode of the parasitic diode are respectively coupled to the drain and source of the P-channel metal-oxide half field effect transistor.

The POH correction circuit includes a Zener diode, a first resistor, a second resistor, a diode, a capacitor, a PNP bipolar transistor, a third resistor, an NPN bipolar transistor, and a fourth resistor. . The cathode of the Zener diode is coupled to the working power source, and the anode of the Zener diode is coupled to the first end of the first resistor, the first end of the second resistor and the anode of the diode. The cathode is coupled to the first end of the capacitor and the emitter of the PNP bipolar transistor, the second end of the first resistor is coupled to the second end of the capacitor to ground, and the base and collector of the PNP bipolar transistor are separately coupled Connected to the second end of the second resistor and the first end of the third resistor, the second end of the third resistor is coupled to the base of the NPN bipolar transistor, and the collector of the NPN bipolar transistor is coupled to the fourth The first end of the resistor is connected to the gate of the N-channel MOSFET, the emitter of the NPN bipolar transistor is coupled to ground, and the second end of the fourth resistor is coupled to the working power source.

In an embodiment of the present invention, the microcontroller is coupled to the hot-plug detection pin, and the microcontroller determines whether to output the hot-plug detection signal according to the voltage level of the hot-plug detection pin.

In an embodiment of the invention, the display device includes a television or a computer monitor.

In summary, the display device according to an embodiment of the present invention has a POH switch circuit that determines whether to turn on and transmit the standby power according to the working power and the hot-plug detection signal related to the hot-plug detection pin of the HDMI port. To the power pin of the HDMI port, in addition, its POH correction circuit determines whether the POH switch circuit is conducting according to the working power. When the display device is coupled to an external device with external power supply through the HDMI port, even if the display device is disconnected from the AC power source and then reconnected to the AC power source within a short period of time, the device can still be turned on and off normally.

In order to make the above and other objects, features, and advantages of the present invention more comprehensible, preferred embodiments are described below in detail with reference to the accompanying drawings, as follows.

In order to make the description of this disclosure more detailed and complete, the following presents an illustrative description of the implementation modes and specific embodiments of the present invention, but this is not a limited form of implementing or applying the specific embodiments of the present invention. In addition, some conventional elements that are not related to the technical features of the present invention are omitted, and the same or similar symbols in the embodiments represent the same or similar elements. As used herein, when an element is referred to as being "connected" or "coupled" to another element, it can be that the element is directly connected or coupled to the other element; or that there is a Or more additional elements, that is, one element is connected to another element via one or more additional elements. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no additional elements there.

3 is a circuit block diagram of a display device having an HDMI port supporting a POH function according to an embodiment of the present invention. Referring to FIG. 1 and FIG. 3 at the same time, a POH correction circuit 15 is added to the conventional display device 1 shown in FIG. 1 to form a display device 1 'according to an embodiment of the present invention. In other words, the display device 1 ′ according to an embodiment of the present invention includes an HDMI port 11, a power supply 12, a microcontroller 13, a POH switch circuit 14, and a POH correction circuit 15, wherein the HDMI port 11, the power supply 12, and the micro The coupling relationship and working principle of the controller 13 and the POH switch circuit 14 have been described in the foregoing, and will not be repeated, and the POH correction circuit 15 is coupled to the working power supply Vop and the POH switch circuit 14.

FIG. 4 is a circuit diagram of the POH switch circuit 14 and the POH correction circuit 15 shown in FIG. 3. Please refer to FIG. 3 and FIG. 4 at the same time. The POH correction circuit 15 includes a Zener diode D21, a first resistor R21, a second resistor R22, a diode D22, a capacitor C21, a PNP bipolar transistor Q21, and a third The resistor R23, the NPN bipolar transistor Q22, and the fourth resistor R24. Among them, the cathode of the Zener diode D21 is coupled to the working power source Vop, and the anode of the Zener diode D21 is coupled to the first terminal of the first resistor R21, the first terminal of the second resistor R22, and the diode D22. The anode and cathode of diode D22 are coupled to the first terminal of capacitor C21 and the emitter of PNP bipolar transistor Q21, the second terminal of first resistor R21 and the second terminal of capacitor C21 are coupled to ground, and PNP double The base and collector of the polar transistor Q21 are respectively coupled to the second terminal of the second resistor R22 and the first terminal of the third resistor R23, and the second terminal of the third resistor R23 is coupled to the NPN bipolar transistor Q22. The base of the NPN bipolar transistor Q22 is coupled to the first end of the fourth resistor R24 and the gate of the N-channel MOSFET half-effect transistor Q12, and the emitter of the NPN bipolar transistor Q22 is coupled to ground The second terminal of the fourth resistor R24 is coupled to the working power source Vop.

Compared with that shown in FIG. 2, the gate of the N-channel MOSFET half-effect transistor Q12 shown in FIG. 4 is coupled to the fourth resistor R24 through the resistor R14 and the capacitor C12, and then coupled to the working power supply through the fourth resistor R24. Vop, the resistor R14 and the capacitor C12 are used to provide the voltage regulation filtering function for the working power supply Vop, and the fourth resistor R24 is used to provide the NPN bipolar transistor Q22 on-time current limiting protection function. In addition, the collector of the NPN bipolar transistor Q22 is coupled to the gate of the N-channel metal-oxide-semiconductor field effect transistor Q12 through the resistor R14 and the capacitor C12.

When the display device 1 'is connected to the AC power supply Vac and enters the start-up mode to establish the working power supply Vop, the Zener diode D21 will be turned on, and the emitter voltage of the PNP bipolar transistor Q21 is the voltage provided by the working power supply Vop (equivalent From the voltage drop of the first resistor R21) minus the forward voltage drop of the diode D22 (about 0.7 V), the base voltage of the PNP bipolar transistor Q21 is the voltage provided by the operating power source Vop minus the second The voltage drop of the resistor R22, at this time, the emitter-to-base voltage of the PNP bipolar transistor Q21 will not be large enough to make the PNP bipolar transistor Q21 non-conducting, and then the base-to-emitter voltage of the NPN bipolar transistor Q22 It will not be large enough to prevent the NPN bipolar transistor Q22 from conducting, so the POH correction circuit 15 does not affect the POH switch circuit 14. Therefore, when the working power supply Vop has been established and the N-channel metal-oxide-semiconductor field effect transistor Q12 is turned on, when the display device 1 ′ is coupled to an external device without external power supply through the HDMI port 11 having a POH function, the micro-control The device 13 monitors the hot-plug detection signal HPD output from the HDMI port 11 coupled to the external HDMI port to control the conduction of the P channel metal-oxide-semiconductor half-effect transistor Q11, and the standby power source Vsb passes through the conductive P-channel metal-oxide-semiconductor half-effect transistor Q11. The N-channel metal-oxide-semiconductor half-effect transistor Q12 is transmitted to the power pin 111 of the HDMI port 11 to supply power to an external device.

In addition, when the operating power supply Vop has been established and the N-channel metal-oxide-semiconductor field effect transistor Q12 is turned on, when the display device 1 'is coupled to an external device powered by an external power supply through an HDMI port 11 having a POH function, the external device is It has an external power supply and does not have a line design that accepts HDMI port 11 power supply, so that the standby power Vsb cannot be transmitted to the external device through the power pin 111 of the HDMI port 11, but the external device will pass the power pin 111 of the HDMI port 11 and The N-channel metal-oxide-semiconductor field effect transistor Q12 and the parasitic diode D11 that are turned on in the POH switch circuit 14 transmit power to the standby power source Vsb of the display device 1. When the display device 1 turns off the AC power supply Vac and then turns on the AC power supply Vac again for a short time, the POH correction circuit 15 will affect the POH switch circuit 14, that is, the POH correction circuit 15 will monitor the AC power supply according to the voltage change of the working power supply Vop. Vac is turned off to control the N-channel MOSFET half-effect transistor Q12 in the POH switch circuit 14 to be non-conducting, making it impossible for an external device to supply reverse power to the standby power source Vsb. The voltage of the standby power source Vsb will drop due to the disconnection of the AC power source Vac It is low enough to trigger the software reset of the microcontroller 13 through the voltage climbing action when the standby power source Vsb is established after the AC power source Vac is turned on again, so as to re-enter the standby mode and then enter the boot mode normally.

The following describes how the POH correction circuit 15 affects the POH switch circuit 14 when the display device 1 'is disconnected from the AC power source Vac for a short time. When the AC power supply Vac is turned off, the voltage levels of the standby power supply Vsb and the working power supply Vop generated by the power supply 12 by converting the AC power supply Vac begin to decrease. Due to the energy storage function of the capacitor C21, the emitter voltage of the PNP bipolar transistor Q21 decreases more slowly than the base voltage. As a result, the voltage level of the operating power supply Vop drops to a certain level because of the PNP bipolarity. The emitter-to-base voltage of transistor Q21 becomes large enough to make PNP bipolar transistor Q21 conductive, and the base-to-emitter voltage of NPN bipolar transistor Q22 becomes large enough to make NPN bipolar transistor Q22 conductive. The gate of the N-channel metal-oxide-semiconductor half-effect transistor Q12 is equivalent to coupling to ground. The gate of the N-channel metal-oxide-semiconductor half-effect transistor Q12 is not large enough to the source voltage, and the N-channel metal-oxide-semiconductor half-effect transistor Q12 becomes ineffective. It is turned on to affect the POH switch circuit 14 and prevent external devices from supplying reverse power to the standby power source Vsb.

In summary, in the display device 1 ′ of an embodiment of the present invention, the POH switch circuit 14 is determined according to the working power supply Vop and the hot-plug detection signal HPD related to the hot-plug detection pin 112 of the HDMI port 11. Whether the standby power supply Vsb is transmitted to the power supply pin 111 of the HDMI port 11 or not, and the POH correction circuit 15 thereof determines whether the POH switch circuit 14 is conductive according to the working power supply Vop. When the display device 1 'is coupled to an external device powered by an external power source through the HDMI port 11, even if the display device 1' is first disconnected from the AC power source Vac and then reconnected to the AC power source Vac within a short period of time, the machine can still be turned on and off normally.

Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications and retouching without departing from the spirit and scope of the present invention. The scope of protection shall be determined by the scope of the attached patent application.

1, 1’‧‧‧ display device

11‧‧‧HDMI port

111‧‧‧ Power Pin

112‧‧‧Hot plug detection pin

12‧‧‧ Power Supply

13‧‧‧Microcontroller

14‧‧‧POH switch circuit

15‧‧‧POH correction circuit

C11, C12, C21‧‧‧ capacitors

D11, D12‧‧‧‧ Parasitic Diode

D21‧‧‧Zina Diode

D22‧‧‧ Diode

Q11‧‧‧P Channel Metal Oxide Half Field Effect Transistor

Q12‧‧‧N Channel Metal Oxide Half Field Effect Transistor

Q13‧‧‧NPN Bipolar Transistor

Q21‧‧‧PNP Bipolar Transistor

Q22‧‧‧NPN Bipolar Transistor

R11 ～ R15‧‧‧Resistor

R21‧‧‧First resistor

R22‧‧‧Second resistor

R23‧‧‧Third resistor

R24‧‧‧Fourth resistor

CMD‧‧‧ Power On Command

HPD‧‧‧Hot plug detection signal

PS_ON‧‧‧ Power on signal

Vac‧‧‧AC Power

Vop‧‧‧ Power Supply

Vsb‧‧‧ Standby Power

FIG. 1 is a circuit block diagram of an existing display device with an HDMI port supporting the POH function; FIG. 2 is a circuit diagram of the POH switching circuit shown in FIG. 1; and FIG. 3 is a diagram of a POH-enabled circuit according to an embodiment of the present invention. A circuit block diagram of the display device of the HDMI port; and FIG. 4 is a circuit diagram of the POH switch circuit and the POH correction circuit shown in FIG. 3.

Claims (3)

A display device includes: a High Definition Multimedia Interface (HDMI) port that supports a Power on HDMI (POH) function; a power supply that receives an external AC power source, and A standby power source is output in the standby mode, and the standby power source and a working power source are output in a boot mode; a microcontroller is powered by the standby power source, and the software is reset by triggering a voltage climbing action when the standby power source is established. A POH switch circuit, including a P-channel metal-oxide-semiconductor half-effect transistor, an N-channel metal-oxide-semiconductor half-effect transistor, and a parasitic diode, wherein the source of the P-channel metal-oxide semi-effect transistor is coupled In the standby power supply, the gate of the P-channel metal-oxide-semiconductor half-field-effect transistor is used to receive a hot-plug detection signal related to a hot-plug detection pin of the HDMI port. The drain of the crystal is coupled to the source of the N-channel MOSFET, and the drain and gate of the N-channel MOSFET are coupled to a power pin of the HDMI port and the working power respectively. Source, the anode and cathode of the parasitic diode are respectively coupled to the drain and source of the P-channel metal-oxide-semiconductor field-effect transistor; and a POH correction circuit including a zener diode, a first resistor, a A second resistor, a diode, a capacitor, a PNP bipolar transistor, a third resistor, an NPN bipolar transistor, and a fourth resistor, wherein the cathode of the Zener diode is coupled Connected to the working power source, the anode of the Zener diode is coupled to the first end of the first resistor, the first end of the second resistor is coupled to the anode of the diode, and the cathode of the diode is coupled The first end of the capacitor and the emitter of the PNP bipolar transistor, the second end of the first resistor and the second end of the capacitor are coupled to ground, and the base and collector of the PNP bipolar transistor are respectively The second end of the second resistor is coupled to the first end of the third resistor. The second end of the third resistor is coupled to the base of the NPN bipolar transistor. The collector is coupled to the first end of the fourth resistor and the gate of the N-channel metal-oxide-semiconductor field-effect transistor, and the NPN bipolar Radio crystal coupled to the ground, the fourth resistor and a second terminal coupled to the power supply. The display device according to item 1 of the scope of patent application, wherein the microcontroller is coupled to the hot-plug detection pin, and the microcontroller determines whether to output according to the voltage level of the hot-plug detection pin The hot-plug detection signal. The display device according to item 1 of the scope of patent application, wherein the display device comprises a television or a computer monitor.