CN213817805U

CN213817805U - POE power supply indicating device and Ethernet power supply system

Info

Publication number: CN213817805U
Application number: CN202022681409.8U
Authority: CN
Inventors: 葛振杰
Original assignee: Zhejiang Dahua Technology Co Ltd
Current assignee: Zhejiang Dahua Technology Co Ltd
Priority date: 2020-11-18
Filing date: 2020-11-18
Publication date: 2021-07-27
Anticipated expiration: 2030-11-18

Abstract

The application relates to a POE power supply indicating device and ethernet power supply system, wherein this POE power supply indicating device includes: the PSE power supply comprises a PSE controller, a first power supply, a switch module and a power supply indicating unit, wherein the first power supply is electrically connected with an Out terminal of the PSE controller and used for supplying power to external PD equipment connected with the PSE controller; the switch module is respectively electrically connected with an Out end, a Gate end and a grounding end of the PSE controller and is used for controlling the Out end of the PSE controller to be communicated with a Sense end according to a first control signal output by the PSE controller; the power supply indicating unit comprises a second power supply, a control unit and a light emitting unit, wherein the control unit is respectively electrically connected with a Gate end of the PSE controller, the second power supply and the light emitting unit and is used for controlling the second power supply to be communicated with the light emitting unit according to a first control signal output by the PSE controller. Through the method and the device, the problem of low reliability of the POE power supply system in the related technology is solved, and the technical effect of improving the reliability of the POE power supply system is achieved.

Description

POE power supply indicating device and Ethernet power supply system

Technical Field

The embodiment of the application relates to the technical field of power supplies, in particular to a POE power supply indicating device and an Ethernet power supply system.

Background

Power Over Ethernet (POE) is also called POE Power Over, and is a technology that can transmit Power and data to devices through twisted pair lines in Ethernet. A complete POE Power supply system includes a Power Sourcing Equipment (PSE) and a Powered Device (PD).

The POE power supply can supply power to equipment such as a network telephone, a wireless base station, a camera, a concentrator and a computer, and the electronic equipment which can obtain power supply by virtue of the Ethernet can be used without an extra power socket, so that the time and the cost for configuring a power line can be saved, and the cost of the whole equipment system is relatively reduced. With the increasing application of the POE power supply technology in various technical fields, how to more reliably realize the external indication of the POE power supply system becomes a problem to be solved.

At present, a POE power supply system indicates whether power supply of the POE power supply system is normal and whether network communication is normal through an external indicator lamp. The external indicator lamp has multiple control modes of lighting and turning off, and POE power supply indication in the related technology is usually that a voltage stabilizing diode is arranged at an Out end of a PSE chip, and a light emitting diode indicates whether the power supply of a POE power supply system is normal or not; or adding an MCU controller to read the state of the PSE chip, and indicating whether the power supply of the POE power supply system is normal or not through the light emitting diode according to the read state of the PSE chip. However, in the technical scheme of arranging the voltage stabilizing diode at the Out terminal of the PSE chip, due to leakage current, the detection function of the Out terminal of the PSE chip to the PD device access may fail, and the POE power supply system cannot normally supply power; the technical scheme that the MCU controller is added to read the state of the PSE chip increases the cost of the POE power supply system, the control circuit becomes complex, the reliability of the POE power supply system is reduced, and the maintenance and operation of the POE power supply system are not facilitated.

At present, no effective solution is provided for the problem of low reliability of a POE power supply system in the related art.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a POE power supply indicating device to solve the problem that POE power supply system's reliability is low among the correlation technique at least.

In a first aspect, an embodiment of the present application provides a POE power supply indicating device, where the POE power supply indicating device includes a PSE controller, a first power supply, a switch module, and a power supply indicating unit, where the first power supply is electrically connected to an Out terminal of the PSE controller, and is used to supply power to an external PD device connected to the PSE controller; the switch module is respectively electrically connected with an Out end, a Gate end and a grounding end of the PSE controller and is used for controlling the Out end of the PSE controller to be communicated with a Sense end according to a first control signal output by the PSE controller when the external PD equipment is powered on; the power supply indicating unit comprises a second power supply, a control unit and a light-emitting unit, wherein the control unit is respectively electrically connected with a Gate end of the PSE controller, the second power supply and the light-emitting unit and is used for controlling the second power supply to be communicated with the light-emitting unit according to a first control signal output by the PSE controller; the grounding end is electrically connected with the Sense end of the PSE controller and the light-emitting unit respectively.

In some embodiments, the control unit includes a first switch tube, the first switch tube includes a first control terminal, a first input terminal and a first output terminal, the first control terminal is electrically connected to the Gate terminal, the first input terminal is electrically connected to the second power supply, and the first output terminal is electrically connected to the ground terminal by connecting the light emitting units in series; the first switching tube is used for controlling the second power supply to be communicated with the light-emitting unit according to a first control signal output by the PSE controller when the external PD equipment is powered on.

In some embodiments, the power supply indicating unit further includes: the power supply indicating device comprises a first resistor and a second resistor, wherein a first control end of the power supply indicating unit is connected with the first resistor in series and the Gate end is electrically connected with the first control end of the power supply indicating unit, and a first input end of the power supply indicating unit is connected with the second resistor in series and the second resistor is electrically connected with the second power supply.

In some of these embodiments, the first switch tube comprises an N-channel MOS field effect transistor.

In some embodiments, the switch module includes a second switch tube and a third resistor, the second switch tube includes a second control terminal, a second input terminal and a second output terminal, the second control terminal of the second switch tube is electrically connected to the Gate terminal by connecting the third resistor in series, the second input terminal of the second switch tube is electrically connected to the Out terminal and an external PD device, and the second output terminal of the second switch tube is electrically connected to the first power supply; the second switching tube is used for being switched on or switched off according to a preset voltage value output by the Gate end, so that the Out end of the PSE controller is communicated with or switched off from the Sense end.

In some embodiments, the switch module further includes a fourth resistor, wherein the second output terminal of the second switch tube and the Sense terminal of the PSE controller are electrically connected to the ground terminal by connecting the fourth resistor in series.

In some embodiments, the second switch tube comprises an N-channel MOS field effect transistor.

In some of these embodiments, the light emitting unit comprises a light emitting diode.

In some embodiments, the POE power supply indication apparatus further includes a fifth resistor, wherein the Out terminal of the PSE controller is electrically connected to the first port of the external PD device through the fifth resistor.

In some of these embodiments, the PSE controller further includes an RJ45 interface for connecting with the external PD device, the RJ45 interface further including a first port electrically connected to a first power source and a second port electrically connected to the Out terminal.

In a second aspect, an embodiment of the present application provides a power over ethernet system, including the POE power supply indication device as described in the first aspect.

Compare in correlation technique, the POE power supply indicating device that this application embodiment provided has solved the problem that POE power supply system's reliability is low among the correlation technique, has realized improving the technological effect to POE power supply system reliability.

The details of one or more embodiments of the application are set forth in the accompanying drawings and the description below to provide a more thorough understanding of other features, objects, and advantages of the embodiments of the application.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the embodiments of the application and are not intended to limit the embodiments of the application in any way. In the drawings:

fig. 1 is a block diagram illustrating a POE power supply indication apparatus according to an embodiment of the present application;

fig. 2 is a topology diagram of a POE power supply indication device according to an embodiment of the present application;

fig. 3 is a block diagram of a power over ethernet system according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application more clearly understood, the embodiments of the present application are described and illustrated below with reference to the accompanying drawings and the embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of the application and are not intended to limit the embodiments of the application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments provided in the present application without any creative effort belong to the protection scope of the embodiments of the present application.

It should be apparent that the drawings in the following description are only examples or embodiments of the present application, and it is obvious for a person skilled in the art that the embodiments of the present application can be applied to other similar scenarios according to the drawings without inventive effort. Moreover, it should be further appreciated that such a development effort might be complex and tedious, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, and it should be understood that the present disclosure is not limited to the particular embodiments described herein.

Reference in the embodiments of the present application to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the embodiments of the present application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one of ordinary skill in the art that the embodiments described in the embodiments of this application can be combined with other embodiments without conflict.

Unless otherwise defined, technical or scientific terms referred to in the embodiments of the present application shall have the ordinary meaning as understood by those having ordinary skill in the art to which the embodiments of the present application belong. Reference to "a," "an," "the," and similar terms in the embodiments of the application are not intended to be limiting, but may refer to the singular or the plural. Reference to the terms "comprise," "include," "have" and any variations thereof in the embodiments of the present application, are intended to cover non-exclusive inclusions; for example, a process, method, system, article, or apparatus that comprises a list of steps or modules (elements) is not limited to the listed steps or elements, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. Reference to "connected," "coupled," and the like in connection with embodiments of the present application is not intended to be limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The embodiments of the present application refer to "a plurality" or "a plurality". "and/or" describes an association relationship of associated objects, meaning that three relationships may exist, for example, "A and/or B" may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. Reference to the terms "first," "second," "third," and the like in the embodiments of the application are merely used to distinguish similar objects and do not denote a particular ordering for the objects.

The embodiment provides a POE power supply indicating device. Fig. 1 is a schematic structural diagram of a POE power supply indication device according to an embodiment of the present application, and as shown in fig. 1, the POE power supply indication device includes: the PSE controller comprises a PSE controller 10, a first power supply +48V, a switch module 20 and a power supply indicating unit 30, wherein the first power supply +48V is electrically connected with an Out terminal 101 of the PSE controller 10 and is used for supplying power to external PD equipment connected to the PSE controller 10; the PSE controller 10 includes an Out terminal 101 (corresponding to an output port of the PSE controller 10), a Gate terminal 102 (corresponding to a power supply control port of the PSE controller 10), and a Sense terminal 103 (corresponding to a sampling signal monitoring interface port of the PSE controller 10), the switch module 20 is electrically connected to the Out terminal 101 and the Gate terminal 102 of the PSE controller 10, respectively, and a ground terminal GND, and is configured to control the Out terminal 101 of the PSE controller 10 to communicate with the Sense terminal 103 according to a first control signal output by the PSE controller 10 when the external PD device is powered on; the power supply indicating unit 30 comprises a second power supply +3.3V, a control unit M1 and a light emitting unit D1, wherein the control unit is electrically connected with a Gate terminal 102 of the PSE controller, the second power supply +3.3V and the light emitting unit D1, respectively, and is used for controlling the second unit +3.3V to be electrically connected with a ground terminal GND according to a first control signal output by the PSE controller 10 when the external PD device is powered on; the ground GND is electrically connected to the Sense terminal 103 of the PSE controller 10 and the light emitting unit D1, respectively.

In some embodiments, the control unit M1 includes a first switch tube M1, the first switch tube M1 includes a first control terminal 301, a first input terminal 302 and a first output terminal 303, the first control terminal 301 is electrically connected to the Gate terminal 102, the first input terminal 302 is electrically connected to the +3.3V of the second power supply, and the first output terminal 303 is electrically connected to the ground terminal GND through the series light emitting unit D1; the first switch tube M1 is used for controlling the second power supply +3.3V to communicate with the light-emitting unit D1 according to a first control signal output by the PSE controller 10 when the external PD device is powered on.

In this embodiment, when the PSE controller 10 supplies power to the external PD device, the voltage value of the output voltage at the Gate terminal 102 of the PSE controller 10 is a preset voltage value, at this time, the switch module 20 controls the second port of the RJ45 interface 40 to be electrically connected to the ground terminal GND, so as to control the external PD device to be electrically connected to the ground terminal GND through the RJ45 interface 40, where the voltage for supplying power to the external PD device is equal to the output voltage of +48V of the first power supply; when the external PD device is removed, the current value in the connection branch between the RJ45 interface 40 and the Sense terminal 103 of the PSE controller 10 is 0, the voltage value of the output voltage at the Gate terminal 102 of the PSE controller 10 is 0, the switching module 20 controls the second port of the RJ45 interface 40 to be electrically disconnected from the ground GND, and the PSE controller 10 stops supplying power to the external PD device.

The first control signal may be a high level signal output by the Gate terminal 102, when the PSE controller 10 supplies power to the external PD device, a voltage value of an output voltage of the Gate terminal 102 of the PSE controller 10 is a preset voltage value, at this time, a voltage of the first control terminal 301 of the first switching tube M1 is higher than a voltage of the first input terminal 302, the first switching tube M1 is turned on, the first output terminal 303 is electrically connected with the ground terminal GND through the series connection light emitting unit D1, the second power supply +3.3V supplies power to the light emitting unit D1, at this time, the light emitting unit D1 lights, and it indicates that the current POE supplies power normally. When the external PD device is removed, the PSE controller 10 stops supplying power to the external PD device, the voltage value of the output voltage at the Gate terminal 102 of the PSE controller 10 is 0, at this time, the first switching tube M1 is turned off, and the +3.3V power supply stops supplying power to the light-emitting unit D1, indicating that the current POE is not supplied with power.

In this embodiment, the PSE controller 10 may be a device designed and manufactured according to the POE standard, and configured to detect, classify and power Pd devices in the ethernet according to the POE standard.

In some of these embodiments, the PSE controller 10 further includes an RJ45 interface 40 for connecting with external PD devices, and the RJ45 interface 40 further includes a first port and a second port, wherein the first port is electrically connected with the first power supply +48V, and the second port is electrically connected with the Out terminal 101.

In this embodiment, the first port may be a positive power port, the second port may be a negative power port, when there is an external PD device connected to the RJ45 interface 40, the voltage value of the output voltage at the Gate terminal 102 of the PSE controller 10 is a preset voltage value, at this time, the switch module 20 controls the negative power port of the RJ45 interface 40 to be electrically connected to the ground terminal GND, so as to control the external PD device to be electrically connected to the ground terminal GND through the RJ45 interface 40, at this time, the power supply loop of the external PD device is turned on, and the POE power supply system completes power supply to the external PD device.

In the case that an external PD device is connected to the RJ45 interface 40, the PSE controller 10 may detect, classify and power the external PD device connected through the RJ45 interface 40 according to the POE standard, wherein when the PSE controller 10 detects and classifies the external PD device, the PSE controller 10 may detect and classify the external PD device by changing the output voltage of the Out terminal 101 of the PSE controller 10, thereby changing the voltage across the external PD device.

In the above embodiment, the first switch tube M1 may control the second power supply +3.3V to communicate with the light emitting unit D1 according to the first control signal output by the PSE controller 10 when the external PD device is powered on.

In this embodiment, the +48V output voltage of the first power supply may be +48V, and the preset voltage value may be + 9V.

Fig. 2 is a topology diagram of a POE power supply indication device according to an embodiment of the present application, as shown in fig. 2, in some embodiments, the power supply indication unit 30 further includes: a first resistor R1 and a second resistor R2, wherein the first control terminal 301 of the power indication unit 30 is electrically connected to the Gate terminal 102 through a series first resistor R1, and the first input terminal 302 of the power indication unit 30 is electrically connected to the +3.3V of the second power source through a series second resistor R2.

In this embodiment, both the first resistor R1 and the second resistor R2 can function as a current limiter.

As shown in fig. 2, in some embodiments, the switch module 20 includes a second switch tube M2 and a third resistor R3, the second switch tube M2 includes a second control terminal, a second input terminal and a second output terminal, the second control terminal of the second switch tube M2 is electrically connected to the Gate terminal 102 through the series-connected third resistor R3, the second input terminal of the second switch tube M2 is electrically connected to the Out terminal 101 and the external PD device, and the second output terminal of the second switch tube M2 is electrically connected to the ground terminal GND; the second switching tube M2 is used for switching on or off according to a preset voltage value output by the Gate terminal 102, so that the Out terminal 101 of the PSE controller 10 is connected or disconnected with the Sense terminal 103.

In the present embodiment, when detecting and classifying the external PD device, the voltage value of the output voltage of the Gate terminal 102 of the PSE controller 10 is 0; when the PSE controller 10 supplies power to the external PD device, the voltage value of the output voltage at the Gate terminal 102 of the PSE controller 10 is a preset voltage value, at this time, the voltage at the second control terminal of the second switching tube M2 is greater than the voltage at the second input terminal, the second switching tube M2 is turned on and controls the second port of the RJ45 interface 40 to be electrically connected with the ground terminal GND, thereby controlling the external PD device to be electrically connected with the ground terminal GND through the RJ45 interface 40, at this time, the power supply loop of the external PD device is turned on, and the POE power supply system finishes supplying power to the external PD device.

When the external PD device is removed, the current value in the connection branch between the RJ45 interface 40 and the Sense terminal 103 of the PSE controller 10 is 0, the voltage value of the output voltage at the Gate terminal 102 of the PSE controller 10 is 0, at this time, the second switching tube M2 is turned off, and the electrical connection between the second port of the RJ45 interface 40 and the ground terminal GND is disconnected, so that the electrical connection between the external PD device and the ground terminal GND through the RJ45 interface 40 is controlled to be disconnected, at this time, the power supply loop of the external PD device is disconnected, and the power supply is stopped.

In this embodiment, the first switch transistor M1 and the second switch transistor M2 may be both N-channel MOS field effect transistors, and others, and the light emitting unit D1 may be a light emitting diode D1.

In other embodiments, the first switch tube M1 and/or the second switch tube M2 may also be N-channel junction field response tubes, and the light emitting unit D1 may also be other light emitting elements.

As shown in fig. 2, in some embodiments, the switch module 20 further includes a fourth resistor R4, and the second output terminal of the second switch tube M2 and the Sense terminal 103 of the PSE controller 10 are electrically connected to the ground GND through the series connection of the fourth resistor R4.

In this embodiment, the fourth resistor may function as a current limiter.

As shown in fig. 2, in some embodiments, the POE power indication apparatus further includes a fifth resistor R5, wherein the Out terminal 101 of the PSE controller 10 is electrically connected to the first port of the external PD device through the fifth resistor R5.

With the above embodiment, the first switching tube M1 controls the second power supply +3.3V to communicate with the light-emitting unit D1 according to the first control signal output by the PSE controller 10 when the external PD device is powered on, and controls the second power supply +3.3V to communicate with the light-emitting unit D1 when the PSE controller 10 is powered on the external PD device, so that the light-emitting unit D1 lights; under the condition that outside PD equipment removed, control second power +3.3V and the disconnection of luminescence unit D1, luminescence unit D1 is not bright to whether normally carry out outside instruction to POE power supply system's power supply, compare with the correlation technique, simplified control circuit, the cost is lower, has solved the problem that POE power supply system's reliability is low among the correlation technique, has realized improving the technological effect to POE power supply system reliability.

Fig. 3 is a block diagram of a power over ethernet system according to an embodiment of the present application, and as shown in fig. 3, the power over ethernet system includes a POE power indication device as in the above embodiment, for a system/device embodiment, since it is substantially similar to the above embodiment, the description is relatively simple, and for relevant points, refer to the partial description of the above embodiment.

The working principle of the POE power supply indicating device for indicating the POE power supply is as follows:

in case of detecting and classifying the external PD device, the POE controller sends a first control signal to the first switching tube M1.

In this embodiment, the first control signal may be a preset voltage value output by the Gate terminal 102 of the PSE controller 10, where the preset voltage value may be + 9V; when the PSE controller 10 supplies power to the external PD device, the voltage value of the output voltage of the Gate terminal 102 of the PSE controller 10 is a preset voltage value, at this time, the voltage of the first control terminal 301 of the first switching tube M1 is higher than the voltage of the first input terminal 302, the first switching tube M1 is turned on, the first output terminal 303 is electrically connected with the ground terminal GND through the series connection light-emitting unit D1, the second power supply +3.3V is supplied power to the light-emitting unit D1, at this time, the light-emitting unit D1 lights, and it indicates that the current POE is normally supplied power.

In case the external PD device is removed, the POE controller sends a second control signal to the first switching tube M1.

In this embodiment, the second control signal may be a 0 voltage value output by the Gate terminal 102 of the PSE controller 10. When the external PD device is removed, the PSE controller 10 stops supplying power to the external PD device, the voltage value of the output voltage at the Gate terminal 102 of the PSE controller 10 is 0, at this time, the first switching tube M1 is turned off, and the +3.3V power supply stops supplying power to the light-emitting unit D1, indicating that the current POE is not supplied with power.

The first switching tube M1 controls the second power supply +3.3V to be communicated with the light-emitting unit D1 according to a first control signal output by the PSE controller 10 when the external PD device is powered on, and controls the second power supply +3.3V to be communicated with the light-emitting unit D1 when the PSE controller 10 is powered on the external PD device, so that the light-emitting unit D1 lights; according to the second control signal that PSE controller 10 exported when external PD equipment switched on the power supply, control second power +3.3V and luminescence unit D1's disconnection, when removing external PD equipment, control second power +3.3V and luminescence unit D1's disconnection, thereby luminescence unit D1 stops shining, compare with the correlation technique, control circuit has been simplified, the cost is lower, the problem of POE power supply system's reliability is low among the correlation technique has been solved, the technological effect of improvement to POE power supply system reliability has been realized.

Compared with the prior art, the embodiment of the application has the following advantages:

(1) this application embodiment controls second power and luminescence unit intercommunication through first control signal that first switch tube exported when the PSE controller switches on the power supply at external PD equipment, when the PSE controller supplies power to external PD equipment, controls second power and luminescence unit intercommunication to luminescence unit shines, compares with the correlation technique, has simplified control circuit, and the cost is lower.

(2) The embodiment of this application controls POE power supply system's external instruction function through first switch tube, need not add the MCU controller again in POE power supply system and control it, the POE power supply system who has avoided the numerous and diverse result of control circuit maintains and the difficult problem of maintenance, POE power supply system's reliability has been improved, the problem that POE power supply system's reliability is low among the correlation technique has been solved, the technological effect of improvement to POE power supply system reliability has been realized.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express a few embodiments of the present application, and the description thereof is specific and detailed, but not construed as limiting the scope of the utility model. It should be noted that, for those skilled in the art, variations and modifications can be made without departing from the concept of the embodiments of the present application, and these embodiments are within the scope of the present application. Therefore, the protection scope of the embodiments of the present application shall be subject to the appended claims.

Claims

1. A POE power supply indicating device is characterized by comprising a PSE controller, a first power supply, a switch module and a power supply indicating unit, wherein,

the first power supply is electrically connected with an Out terminal of the PSE controller and used for supplying power to external PD equipment connected with the PSE controller;

the switch module is respectively electrically connected with an Out end, a Gate end and a grounding end of the PSE controller and is used for controlling the Out end of the PSE controller to be communicated with a Sense end according to a first control signal output by the PSE controller when the external PD equipment is powered on;

the power supply indicating unit includes a second power supply, a control unit, and a light emitting unit, wherein,

the control unit is respectively electrically connected with a Gate end of the PSE controller, the second power supply and the light-emitting unit and is used for controlling the second power supply to be communicated with the light-emitting unit according to a first control signal output by the PSE controller;

the grounding end is electrically connected with the Sense end of the PSE controller and the light-emitting unit respectively.

2. The POE power supply indicating device according to claim 1, wherein the control unit comprises a first switching tube, the first switching tube comprises a first control terminal, a first input terminal and a first output terminal, the first control terminal is electrically connected to the Gate terminal, the first input terminal is electrically connected to the second power supply, and the first output terminal is electrically connected to the ground terminal by connecting the light emitting unit in series;

the first switching tube is used for controlling the second power supply to be communicated with the light-emitting unit according to a first control signal output by the PSE controller when the external PD equipment is powered on.

3. The POE power supply indication device of claim 2, wherein the power supply indication unit further comprises: the power supply indicating device comprises a first resistor and a second resistor, wherein a first control end of the power supply indicating unit is connected with the first resistor in series and the Gate end is electrically connected with the first control end of the power supply indicating unit, and a first input end of the power supply indicating unit is connected with the second resistor in series and the second resistor is electrically connected with the second power supply.

4. The POE power supply indication device of claim 2, wherein the first switch transistor comprises an N-channel MOS field effect transistor.

5. The POE power supply indicating device of claim 1, wherein the switch module comprises a second switch tube and a third resistor, the second switch tube comprises a second control terminal, a second input terminal and a second output terminal, the second control terminal of the second switch tube is electrically connected to the Gate terminal by serially connecting the third resistor, the second input terminal of the second switch tube is electrically connected to the Out terminal and an external PD device, and the second output terminal of the second switch tube is electrically connected to the first power supply; the second switching tube is used for being switched on or switched off according to a preset voltage value output by the Gate end, so that the Out end of the PSE controller is communicated with or switched off from the Sense end.

6. The POE power supply indication device of claim 5, wherein the switch module further comprises a fourth resistor, wherein the second output terminal of the second switch tube and the Sense terminal of the PSE controller are electrically connected to the ground terminal by serially connecting the fourth resistor.

7. The POE power supply indication device of claim 5, wherein the second switch transistor comprises an N-channel MOS field effect transistor.

8. The POE power indication device of claim 1, further comprising a fifth resistor, wherein the Out terminal of the PSE controller is electrically connected to the first port of the external PD device via the fifth resistor.

9. The POE power indication device of claim 1, wherein the PSE controller further comprises an RJ45 interface for connecting with the external PD device, the RJ45 interface further comprising a first port and a second port, wherein the first port is electrically connected to the first power source and the second port is electrically connected to the Out terminal.

10. A power over ethernet system comprising the POE power indication device of any of claims 1 to 9.