CN104243175B

CN104243175B - Power backup circuit, POE system and method

Info

Publication number: CN104243175B
Application number: CN201310231092.XA
Authority: CN
Inventors: 王义丰
Original assignee: Hongfujin Precision Industry Shenzhen Co Ltd; Hon Hai Precision Industry Co Ltd
Current assignee: Hongfujin Precision Industry Shenzhen Co Ltd; Hon Hai Precision Industry Co Ltd
Priority date: 2013-06-11
Filing date: 2013-06-11
Publication date: 2017-07-28
Anticipated expiration: 2033-06-11
Also published as: CN104243175A

Abstract

A kind of power backup circuit, including port circuit for detecting, fixed circuit for detecting, voltage conversion circuit and control circuit.Multiple power supply signals correspondence that port circuit for detecting is used to be exported according to the multiple POE port exports multiple port signals in place.The predeterminated voltage that fixed circuit for detecting is used to be exported according to the terminal device exports the first control signal.Voltage conversion circuit is used to being converted to multiple power supply signals that the multiple POE port is exported into the driving voltage needed for the terminal device.Circuit is controlled to be used to enable signal according to first control signal and the multiple port signal output in place.The present invention also provides a kind of POE system and method.Above-mentioned power backup circuit, POE system and method are in parallel using the stand-by power supply as terminal device by multiple POE ports, realize and carry out stand-by power supply to the terminal device of different capacity grade, reduce the cost of stand-by power supply.

Description

Power backup circuit, POE system and method

Technical field

The present invention relates to power backup circuit, more particularly to a kind of power supply applied in POE system and method are standby Use circuit.

Background technology

POE（Power over Ethernet, PoE）Refer to not appoint in existing Ethernet wiring architecture In the case that what is changed, IP is being based on for some（Internet Protocol, IP）Terminal transmission data signal while, The technology of direct current supply can also be provided for this kind equipment.

Existing network interchanger is typically provided with stand-by power supply, as the PSU on the network switch（Power Supply Unit, PSU）During power-off, its normal work is maintained by stand-by power supply, so as to avoid because PSU is powered off suddenly and causes net Capsule information in network interchanger are lost in.But its design cost of the stand-by power supply on existing network interchanger is expensive, and can only Using on a single network switch.Therefore, design a kind of with low cost, big as one using flexible stand-by power supply Research topic.

The content of the invention

In view of this, a kind of power backup circuit need to be provided, it can be by the parallel connection of multiple POE ports to be used as end The stand-by power supply of end equipment.

In addition, also needing to provide a kind of POE system, it can be by the parallel connection of multiple POE ports to be used as end The stand-by power supply of end equipment.

In addition, also needing to provide a kind of POE method, it can be by the parallel connection of multiple POE ports to be used as end The stand-by power supply of end equipment.

The power backup circuit that embodiment of the present invention is provided, for the parallel connection of multiple POE ports to be driven into end End equipment.The power backup circuit includes port circuit for detecting, fixed circuit for detecting, voltage conversion circuit and control circuit. The port circuit for detecting is used to be electrically connected at the multiple POE port, for being supplied according to the multiple Ethernet The multiple port signals in place of multiple power supply signals correspondence output of electric port output.The fixed circuit for detecting is used for according to described The predeterminated voltage of terminal device output exports the first control signal.The voltage conversion circuit is the multiple for being electrically connected at POE port, multiple power supply signals for the multiple POE port to be exported are converted to the terminal and set Standby required driving voltage, to drive the terminal device.It is described control circuit be used for respectively from the fixed circuit for detecting with The port circuit for detecting receives first control signal and the multiple port signal in place, and according to the described first control Signal and the multiple port signal output in place enable signal to the voltage conversion circuit.Wherein, the voltage conversion electricity Road is additionally operable to according to whether receiving the enable signal to judge whether to voltage conversion.

Preferably, the predeterminated voltage is the corresponding voltage of the terminal device theoretical power (horse-power).

Preferably, the fixed circuit for detecting includes the first comparison circuit, the first isolation circuit.First comparison circuit Including multiple first comparing units, controlled for the predeterminated voltage according to the terminal device with multiple reference voltage outputs first Signal.Described first isolation circuit one end is electrically connected with first comparison circuit, and the other end is electrically connected at the port and detectd The common port of slowdown monitoring circuit and the control circuit, first isolation circuit includes multiple first isolated locations, for isolating The first comparison circuit and the port circuit for detecting are stated, so that multiple ports signal in place of port circuit for detecting output is passed Deliver to the control circuit.Wherein, the multiple first isolated location corresponds electrical with the multiple first comparing unit Connection.

Preferably, the power backup circuit also includes sample circuit, and the sample circuit is used to be electrically connected with the electricity Voltage conversion circuit, the electric current of the voltage conversion circuit is flowed through for gathering and the first sampled voltage is exported.

Preferably, the electric current of the sample circuit collection is in the electricity flowed through under full load condition for the terminal device Stream.

Preferably, the power backup circuit also includes the first dynamic sensing circuit, for being electrically connected with the sampling electricity Road, the control circuit and the multiple POE port, for the first sampling electricity exported according to the sample circuit Pressure the second control signal of output, the control circuit is additionally operable in place be believed according to second control signal and the multiple port Number output enable signal to control whether the voltage conversion circuit carries out voltage conversion, the multiple POE port is also Break-off is judged whether according to second control signal.

Preferably, the voltage conversion circuit is when receiving the enable signal, and the voltage conversion circuit carries out electricity Pressure conversion, to drive the terminal device, when not receiving the enable signal, the voltage conversion circuit break-off, The voltage conversion circuit output voltage is 0.

Preferably, first dynamic sensing circuit includes the temporary electricity of signal amplification unit, the second comparison circuit, signal Road, the second isolation circuit, on-off circuit.The signal amplification unit is used for the first sampled voltage for exporting the sample circuit Signal amplification is carried out, to obtain the second sampled voltage.Second comparison circuit includes multiple second comparing units, for basis Second sampled voltage and multiple control signals of reference voltage output second.It is temporary that the signal buffering circuit includes multiple signals Memory cell, for keeping in second control signal.Described second isolation circuit one end is electrically connected at the temporary electricity of the signal Road, the other end is electrically connected at the common port of the port circuit for detecting and the control circuit, the second isolation circuit bag Multiple second isolated locations are included, for isolating the signal buffering circuit and the port circuit for detecting, so that the port is detectd Multiple ports signal in place of slowdown monitoring circuit output is sent to the control circuit.The on-off circuit is described for being electrically connected at Signal buffering circuit, including multiple switch unit, for exporting multiple shutdown signals according to second control signal.Wherein, The multiple POE port judges whether break-off always according to the multiple shutdown signal, and the multiple second compares Unit, multiple signal temporary storage locations, multiple second isolated locations and multiple switch unit, which are corresponded, to be electrically connected with.

Preferably, the quantity of the multiple first comparing unit and the multiple second comparing unit than it is the multiple with Too the quantity of net supply port lacks one, and the multiple POE port exports multiple power supply signals of multiple power grades, Each reference voltage is the voltage of correspondence power grade.

Preferably, every one first comparing unit is used to comparing the predeterminated voltage of terminal device output and corresponding power etc. The reference voltage of level simultaneously exports comparative result signal, and first control signal is many of the multiple first comparing unit output Individual comparative result signal.

Preferably, the control circuit includes multiple and door, and the multiple and door is in the multiple POE port Output enables signal when the power of multiple power supply signals of output is not less than the theoretical power (horse-power) of the terminal device.

Preferably, every one second comparing unit is used for the reference electricity for comparing second sampled voltage and corresponding power grade Press and export comparative result signal, second control signal is multiple comparative results that the multiple second comparing unit is exported Signal.

Preferably, the multiple switch element is used for the multiple comparative results exported according to the multiple second comparing unit The multiple shutdown signals of signal output.

Preferably, work is suspended in each POE port when receiving the shutdown signal of correspondence switch element output Make, the voltage of the power supply signal of output is 0.

Preferably, the control circuit includes microcontroller.

Preferably, the power backup circuit also includes the second dynamic sensing circuit, and second dynamic sensing circuit is used In being electrically connected with the sample circuit and the micro-control unit, for the first sampled voltage exported according to the sample circuit The second control signal is exported, the micro-control unit is additionally operable in place believe according to second control signal and the multiple port Number output enable signal, to control whether the voltage conversion circuit carries out voltage conversion.

Preferably, the micro-control unit is also electrically connected at the multiple POE port, the microcontroller list Member is additionally operable to export the 3rd control signal according to second control signal, and the multiple POE port is always according to described 3rd control signal judges whether break-off.

Preferably, second dynamic sensing circuit includes signal amplification unit, analog-digital converter.The signal amplification is single Member, the first sampled voltage for the sample circuit to be exported carries out signal amplification, to obtain the second sampled voltage.The mould Number converter is used to export the second control signal according to second sampled voltage.

Embodiment of the present invention provides a kind of POE system, including multiple POE ports, terminal device And power backup circuit.The power backup circuit includes port circuit for detecting, fixed circuit for detecting, voltage conversion circuit and control Circuit processed.The port circuit for detecting is used to be electrically connected at the multiple POE port, for according to the multiple The multiple port signals in place of multiple power supply signals correspondence output of POE port output.The fixed circuit for detecting is used for The predeterminated voltage exported according to the terminal device exports the first control signal.The voltage conversion circuit is used to be electrically connected at The multiple POE port, multiple power supply signals for the multiple POE port to be exported are converted to institute The driving voltage needed for terminal device is stated, to drive the terminal device.The control circuit is used to detect from the fixation respectively Slowdown monitoring circuit receives first control signal and the multiple port signal in place with the port circuit for detecting, and according to described First control signal and the multiple port signal output in place enable signal to the voltage conversion circuit.Wherein, the electricity Voltage conversion circuit is additionally operable to according to whether receiving the enable signal to judge whether to voltage conversion.

A kind of POE method of embodiment of the present invention, for being incited somebody to action in the power backup circuit of POE system Multiple POE ports are in parallel with drives terminal equipment, and the power backup circuit, which includes port circuit for detecting, fixation, to be detectd Slowdown monitoring circuit, voltage conversion circuit and control circuit.The POE method comprises the following steps：The port circuit for detecting The multiple power supply signals correspondence exported according to the multiple POE port exports multiple port signals in place to the control Circuit processed；The fixed circuit for detecting exports the first control signal to the control electricity according to the predeterminated voltage of the terminal device Road；The control circuit enables signal to the electricity according to first control signal and the multiple port signal output in place Voltage conversion circuit；The voltage conversion circuit judges whether to voltage conversion according to whether receiving the enable signal.

Preferably, the power backup circuit also includes sample circuit and the first dynamic sensing circuit, wherein the control The step of circuit enables signal according to first control signal and the multiple port signal output in place includes：The control Circuit enables signal to the control circuit according to first control signal and the multiple port signal output in place, described The first sampled voltage that first dynamic sensing circuit is exported according to the sample circuit exports the second control signal, the control electricity Road enables signal to the control circuit always according to second control signal and the multiple port signal output in place.

Preferably, the control circuit is enabled according to first control signal and the multiple port signal output in place The step of signal, also includes：The multiple POE port judges whether to suspend work always according to second control signal Make.

Preferably, the control circuit includes micro-control unit, the control circuit according to first control signal and The step of the multiple port signal output in place enables signal to the voltage conversion circuit includes：The micro-control unit root Signal is enabled to the voltage conversion circuit according to first control signal and the multiple port signal output in place.

Preferably, the power backup circuit also includes sample circuit and the second dynamic sensing circuit, the microcontroller list The step of member enables signal according to first control signal and the multiple port signal output in place includes：The microcontroller Unit enables signal, the second dynamic detection electricity according to first control signal and the multiple port signal output in place The first sampled voltage that road is exported according to the sample circuit exports the second control signal, and the micro-control unit is always according to described Second control signal and the multiple port signal output in place enable signal.

Preferably, the micro-control unit makes according to first control signal and the multiple port signal output in place Can also it include the step of signal：The micro-control unit exports the 3rd control signal always according to second control signal, described Multiple POE ports judge whether break-off always according to the 3rd control signal.

Preferably, the voltage conversion circuit judges whether to voltage conversion according to whether receiving the enable signal Step includes：The voltage conversion circuit is when receiving the enable signal, and the voltage conversion circuit carries out voltage conversion, When not receiving the enable signal, the voltage conversion circuit break-off, the voltage conversion circuit output voltage is 0。

Above-mentioned power backup circuit, POE system and method are by the parallel connection of multiple POE ports to be used as end The stand-by power supply of end equipment, realizes and carries out stand-by power supply to the terminal device of different capacity grade, reduce stand-by power supply into This.

Brief description of the drawings

Fig. 1 is the schematic diagram of the embodiment of POE system one of the present invention.

Fig. 2 is the module map of power backup circuit first embodiment of the present invention.

Fig. 3 is the module map of power backup circuit second embodiment of the present invention.

Fig. 4 is the details module map of the embodiment of power backup circuit one in Fig. 3.

Fig. 5 is the physical circuit figure of the embodiment of power backup circuit one in Fig. 4.

Fig. 6 is the module map of the embodiment of power backup circuit the 3rd of the present invention.

Fig. 7 is the module map of the embodiment of power backup circuit the 4th of the present invention.

Fig. 8 is the details module map of the embodiment of power backup circuit one in Fig. 7.

Fig. 9 is the physical circuit figure of the embodiment of power backup circuit one in Fig. 8.

Figure 10 is the flow chart of the embodiment of POE method one of the present invention.

Figure 11 is the details flow chart of POE method in Figure 10.

Figure 12 is the flow chart of another embodiment of POE method of the present invention.

Figure 13 is the details flow chart of POE method in Figure 12.

Main element symbol description

POE port 10a, 10b, 10c, 10d

Power backup circuit 20,20a, 20b

Terminal device 30

Port circuit for detecting 200

Fixed circuit for detecting 202,202a, 202b

First comparison circuit 2022

First comparing unit 2022a, 2022b, 2022c

First isolation circuit 2024

First isolated location 2024a, 2024b, 2024c

Voltage conversion circuit 204

Control circuit 206

Sample circuit 208

First dynamic sensing circuit 210

Signal amplification unit 2100,2122

Second comparison circuit 2102

Second comparing unit 2102a, 2102b, 2102c

Signal buffering circuit 2104

Signal temporary storage location 2104a, 2104b, 2104c

Second isolation circuit 2106

Second isolated location 2106a, 2106b, 2106c

On-off circuit 2108

Switch element 2108a, 2108b, 2108c

Second dynamic sensing circuit 212

Micro-control unit U1

Analog-digital converter U2

Sampling resistor Rs

Reference voltage Vref 1, Vref2, Vref3

First comparator C11, C12, C13

First diode D11, D12, D13

With door AN1, AN2, AN3

Amplifier A1

Second comparator C21, C22, C23

OR gate OR1, OR2, OR3

Second diode D21, D22, D23

Electronic switch Q1, Q2, Q3

Following embodiment will further illustrate the present invention with reference to above-mentioned accompanying drawing.

Embodiment

Fig. 1 is the schematic diagram of the embodiment of POE system one of the present invention.In the present embodiment, POE System includes multiple POE port 10a, 10b, 10c, 10d（In the present embodiment, only exemplified by four, but not It is limited with four, fewer of more than four POE ports can be included）, power backup circuit 20 and terminal device 30, Realization is connected in parallel with drives terminal equipment 30 using multiple POE port 10a, 10b, 10c, 10d.In this embodiment party In formula, POE port 10a, 10b, 10c, 10d side can be correspondingly connected to end equipment of powering by many RJ45 wiring （Power Sourcing Equipment, PSE）Port, opposite side can be connected in parallel to power backup circuit 20.At other Embodiment in, POE port 10a, 10b, 10c, 10d can be also integrated into PSE, i.e., be directly the power supply on PSE Port, also or, POE port 10a, 10b, 10c, 10d and power backup circuit 20 may also be arranged on terminal device 30 In.

Fig. 2 is the module map of the embodiments of power backup circuit 20a mono- of the present invention.In the present embodiment, power backup Circuit 20a includes port circuit for detecting 200, fixed circuit for detecting 202, voltage conversion circuit 204, control circuit 206.Port is detectd Slowdown monitoring circuit 200 is electrically connected at multiple POE port 10a, 10b, 10c, 10d, according to multiple POE ports The multiple port signals in place of multiple power supply signals correspondence output of 10a, 10b, 10c, 10d output extremely control circuit 206.Fixation is detectd The predeterminated voltage that slowdown monitoring circuit 202 is exported according to terminal device 30 exports the first control signal to control circuit 206.Voltage conversion electricity Road 204 is electrically connected at multiple POE port 10a, 10b, 10c, 10d, by multiple POE port 10a, 10b, Multiple power supply signals of 10c, 10d output are converted to the driving voltage needed for terminal device 30, with drives terminal equipment 30.Control Circuit 206 is electrically connected at port circuit for detecting 200, fixed circuit for detecting 202 and voltage conversion circuit 204, respectively from fixation Circuit for detecting 202 receives the first control signal and multiple ports signal in place with control circuit 206, and according to the first control signal And multiple port signal outputs in place enable signal to voltage conversion circuit 204.Wherein, voltage conversion circuit 204 is always according to being The no enable signal that receives judges whether to voltage conversion.In the present embodiment, voltage conversion circuit 204 makes receiving During energy signal, voltage conversion circuit 204 carries out voltage conversion, with drives terminal equipment 30, when not receiving enable signal, electricity The break-off of voltage conversion circuit 204, the output voltage of voltage conversion circuit 204 is 0.

As the further improvement of an embodiment of the present invention, power backup circuit 20a also includes sample circuit 208 and the One dynamic sensing circuit 210, as shown in figure 3, being the module map of another embodiments of power backup circuit 20a of the present invention.At this In embodiment, sample circuit 208 is electrically connected with voltage conversion circuit 204, and the electricity of voltage conversion circuit 204 is flowed through for gathering Flow and export the first sampled voltage.First dynamic sensing circuit 210 is electrically connected with sample circuit 208, controls circuit 206 and multiple POE port 10a, 10b, 10c, 10d, the control of the first sampled voltage output second exported according to sample circuit 208 are believed Number, multiple ports signal output in place that control circuit 206 is exported always according to the second control signal and port circuit for detecting 200 makes Whether energy signal, voltage conversion is carried out with control voltage change-over circuit 204.In the present embodiment, voltage conversion circuit 204 exists When receiving enable signal, voltage conversion circuit 204 carries out voltage conversion, and with drives terminal equipment 30, enable is not being received During signal, the break-off of voltage conversion circuit 204, the output voltage of voltage conversion circuit 204 is 0.Multiple POE ports 10a, 10b, 10c, 10d judge whether break-off always according to the second control signal.

It should be noted that because terminal device 30 is powered by voltage conversion circuit 204, so sample circuit 208, which can both be electrically connected to voltage conversion circuit 204, can be electrically connected to terminal device 30 to carry out current sample, also to enter Row current sample.

Flowed down it should be noted that the electric current that sample circuit 208 is gathered is preferably terminal device 30 in full load condition The electric current of warp, so that when multiple POE port 10a, 10b, 10c, 10d are further run according to terminal device 30 Required peak power is come the number of POE port 10a, 10b, 10c, 10d needed for determining.So as to realize that power supply is standby The power supply signal provided with circuit 20a is closer to the actual demand under the working condition of terminal device 30.

Fig. 4 is the details module map of the embodiments of power backup circuit 20a mono- in Fig. 3.In the present embodiment, fixation is detectd Slowdown monitoring circuit 202 includes the first comparison circuit 2022, the first isolation circuit 2024.The one end of first isolation circuit 2024 is electrically connected at First comparison circuit 2022, the other end is electrically connected at the common port of port circuit for detecting 200 and control circuit 206.First ratio Compared with circuit 2022 include multiple first comparing unit 2022a, 2022b, 2022c, every one first comparing unit 2022a, 2022b, 2022c exports multiple comparative results according to the predeterminated voltage of terminal device 30 with multiple reference voltage Vrefs 1, Vref2, Vref3 Signal.In other words, the first control signal that fixed circuit for detecting 202 is exported is multiple first comparing unit 2022a, 2022b, Multiple comparative result signals of 2022c outputs.First isolation circuit 2024 include multiple first isolated location 2024a, 2024b, 2024c, for isolating the first comparison circuit 2022 and port circuit for detecting 200, so that the output of port circuit for detecting 200 is multiple Port signal in place is sent to control circuit 206.

It should be noted that in the present embodiment only by taking four POE ports 10a, 10b, 10c, 10d as an example, First control signal of the exportable 4 kinds of power grades of three first comparing units 2022a, 2022b, 2022c, therefore, corresponding One comparing unit 2022a, 2022b, 2022c is three, and corresponding reference voltage Vref 1, Vref2, Vref3 are also three, the One isolated location 2024a, 2024b, 2024c and first comparing unit 2022a, 2022b, 2022c, which is corresponded, to be electrically connected with, therefore First isolated location 2024a, 2024b, 2024c is also three.For N (N=1,2,3,4 ...) individual POE port 10a, 10b, 10c, 10d, corresponding first comparing unit 2022a, 2022b, 2022c number are that (N-1) is individual.In other words, first is relatively more single First 2022a, 2022b, 2022c, first isolated location 2024a, 2024b, 2024c quantity than POE port 10a, 10b, 10c, 10d quantity few one.

In the present embodiment, the first dynamic sensing circuit 210 includes signal amplification unit 2100, the second comparison circuit 2102nd, signal buffering circuit 2104, the second isolation circuit 2106, on-off circuit 2108.Signal amplification unit 2100 will sample electric The first sampled voltage that road 208 is exported is amplified, to obtain the second sampled voltage.Second comparison circuit 2102 includes multiple the Two comparing unit 2102a, 2102b, 2102c, the second sampled voltage exported according to signal amplification unit 2100 and multiple references Voltage Vref1, Vref2, Vref3 export multiple comparative result signals.In other words, the of the first dynamic sensing circuit 210 output Two control signals are multiple comparative result signals that multiple second comparing unit 2102a, 2102b, 2102c are exported.Signal is kept in Circuit 2104 includes multiple signal temporary storage location 2104a, 2104b, 2104c, for keeping in the output of the second comparison circuit 2102 Second control signal.Second isolation circuit 2106 is electrically connected at signal buffering circuit 2104 and port circuit for detecting 200 and control The common port of circuit 206 processed, including multiple second isolated location 2106a, 2106b, 2106c, for isolation signals buffering circuit 2104 with port circuit for detecting 200 so that port circuit for detecting 200 export multiple ports signal in place be sent to control circuit 206.On-off circuit 2108 is electrically connected at signal buffering circuit 2104, including multiple switch unit 2108a, 2108b, 2108c, The second control signal kept according to signal temporary storage location exports multiple shutdown signals.Multiple POE port 10a, 10b, 10c, 10d judge whether break-off always according to multiple switch unit 2108a, 2108b, 2108c multiple shutdown signals exported, When multiple POE port 10a, 10b, 10c, 10d are receiving correspondence switch element 2108a, 2108b, 2108c output Shutdown signal when, break-off, POE port 10a, 10b, 10c, 10d output power supply signal voltage be 0.

It should be noted that in the present embodiment only by taking four POE ports 10a, 10b, 10c, 10d as an example, By the first dynamic sensing circuit 210 export the second control signal realize to multiple POE port 10a, 10b, 10c, Peak power required when further being run according to terminal device 30 10d come the POE port 10a needed for determining, 10b, 10c, 10d number.And in order to ensure terminal device 30, at least need to make a POE port 10a be in work shape State.Therefore, exemplified by four POE ports 10a, 10b, 10c, 10d, it can at most close three POE ports 10b、10c、10d.Therefore, corresponding second comparing unit 2102a, 2102b, 2102c are three, corresponding reference voltage Vref 1, Vref2, Vref3 also be three, signal temporary storage location 2104a, 2104b, 2104c, the second isolated location 2106a, 2106b, 2106c, switch element 2108a, 2108b, 2108c are corresponded with second comparing unit 2102a, 2102b, 2102c electrically to be connected Connect, therefore signal temporary storage location 2104a, 2104b, 2104c, the second isolated location 2106a, 2106b, 2106c, switch element 2108a, 2108b, 2108c are three.For N (N=1,2,3,4 ...) individual POE port 10a, 10b, 10c, 10d, Corresponding second comparing unit 2102a, 2102b, 2102c number is that (N-1) is individual.In other words, the second comparing unit 2102a, 2102b, 2102c, signal temporary storage location 2104a, 2104b, 2104c, the second isolated location 2106a, 2106b, 2106c, switch Quantity few one of unit 2108a, 2108b, 2108c quantity than POE port 10a, 10b, 10c, 10d.

Fig. 5 is the physical circuit figure of the embodiments of power backup circuit 20a mono- in Fig. 4.Power backup circuit 20a includes end Mouth circuit for detecting 200, fixed circuit for detecting 202a, voltage conversion circuit 204, control circuit 206, sample circuit 208 and first Dynamic sensing circuit 210.In the present embodiment, only by taking four POE ports 10a, 10b, 10c, 10d as an example.Port Circuit for detecting 200 includes the first sense terminal, the second sense terminal, the 3rd sense terminal, the 4th sense terminal, the first signal output part, the Binary signal output end, the 3rd signal output part, the 4th signal output part, the first sense terminal, the second sense terminal, the 3rd sense terminal, 4th sense terminal is used for correspondence and detects POE port 10a, 10b, 10c, 10d, and the first signal output part, secondary signal are defeated Going out end, the 3rd signal output part, the 4th signal output part is used for correspondence output POE port 10a, 10b, 10c, 10d Port signal in place.There is power supply signal output when the sense terminal of port circuit for detecting 200 first detects POE port 10a When, i.e., when too net supply port 10a can be powered, the first signal output part of port circuit for detecting 200 export with Too net supply port 10a port signal in place, is detected also such as similarly for other POE ports 10b, 10c, 10d This.Port circuit for detecting 200 is that prior art realizes whether POE port 10a, 10b, 10c, 10d can have been carried out The detection module of power supply, so being no longer described in detail.

In the present embodiment, fixed circuit for detecting 202a includes multiple first comparing unit 2022a, 2022b, 2022c And multiple first isolated location 2024a, 2024b, 2024c.In the present embodiment, multiple first comparing unit 2022a, 2022b, 2022c are multiple first comparator C11, C12, C13, and multiple first isolated location 2024a, 2024b, 2024c are many Individual first diode D11, D12, D13.First comparator C11 includes positive input, reverse input end and output end.First ratio Positive input compared with device C11 receives reference voltage Vref 1, and first comparator C11 reverse input end is electrically connected at terminal Equipment 30, the predeterminated voltage that receiving terminal apparatus 30 is exported, first comparator C11 output end is electrically connected at the first diode D11 positive pole, the first diode D11 negative pole is electrically connected at the common port of port circuit for detecting 200 and control circuit 206. First comparator C12 includes positive input, reverse input end and output end.First comparator C12 positive input is received Reference voltage Vref 2, first comparator C12 reverse input end is electrically connected at terminal device 30 and first comparator C11's Common port, the predeterminated voltage that receiving terminal apparatus 30 is exported, first comparator C12 output end is electrically connected at the first diode D12 positive pole, the first diode D12 negative pole is electrically connected at the common port of port circuit for detecting 200 and control circuit 206. First comparator C13 includes positive input, reverse input end and output end.First comparator C13 positive input is received Reference voltage Vref 3, first comparator C13 reverse input end is electrically connected at terminal device 30 and first comparator C11's Common port, the predeterminated voltage that receiving terminal apparatus 30 is exported, first comparator C13 output end is electrically connected at the first diode D13 positive pole, the first diode D13 negative pole is electrically connected at the common port of port circuit for detecting 200 and control circuit 206. The present invention other embodiment in, first comparing unit 2022a, 2022b, 2022c be alternatively other realize voltage ratio compared with Element or module, first isolated location 2024a, 2024b, 2024c be alternatively the element or module that other realize signal isolation, So being no longer described in detail.

It should be noted that the predeterminated voltage that terminal device 30 is exported is the corresponding voltage of the theoretical power (horse-power) of terminal device 30. The theoretical power (horse-power) of terminal device 30 is the sign power sum of all parts included.In other words, terminal device 30 is exported Voltage signal corresponding to the power sum for all elements that predeterminated voltage is included by terminal device 30.In present embodiment In, reference voltage Vref 3 is more than reference voltage Vref 2 and reference voltage Vref 2 is more than reference voltage Vref 1, first comparator The predeterminated voltage and reference voltage Vref 1, Vref2, Vref3 that C11, C12, C13 are exported according to terminal device 30 are compared simultaneously Comparative result signal is exported, so as to realize the predeterminated voltage output first that fixed circuit for detecting 202a is exported according to terminal device 30 Control signal.

It should be noted that in the present embodiment, because only using four POE port 10a, 10b, 10c, 10d as Example, each POE port 10a, 10b, 10c, 10d meet IEEE802.3 standards, each POE port 10a, 10b, 10c, 10d can provide 25W maximum output, therefore, four POE ports 10a, 10b, 10c, 10d can provide 100W Maximum output, according to exportable four power grades of POE port 10a, 10b, 10c, 10d quantity power supply believe Number, i.e. 0~25W, 25~50W, 50~75W, 75~100W, tetra- power grades.Therefore, in the present embodiment, terminal device 30 Theoretical power (horse-power) preferably need be less than or equal to 100W.For example, 0<（The theoretical power (horse-power) of terminal device 30）≤ 25W, terminal The predeterminated voltage that equipment 30 is exported is the voltage signal less than 1.25V, in 25W<（The theoretical power (horse-power) of terminal device 30）≤ 50W, The predeterminated voltage that terminal device 30 is exported is the voltage signal less than 2.5V and more than or equal to 1.25V, in 50W<（Terminal device 30 theoretical power (horse-power)）≤ 75W, the predeterminated voltage that terminal device 30 is exported is the voltage less than 3.75V and more than or equal to 2.5V Signal, in 75W<（The theoretical power (horse-power) of terminal device 30）≤ 100W, the predeterminated voltage that terminal device 30 is exported is less than 5V and greatly In or equal to 3.75V voltage signal.The theoretical power (horse-power) of terminal device 30 is bigger, and the predeterminated voltage that it is exported is bigger.

It should be noted that in the present embodiment, each reference voltage Vref 1, Vref2, Vref3 are correspondence power etc. The voltage of level.Therefore, reference voltage Vref 1 is 1.25V, and reference voltage Vref 2 is 2.5V, and reference voltage Vref 3 is 3.75V.Cause Present embodiment is only by taking four POE ports 10a, 10b, 10c, 10d as an example, therefore the theoretical power (horse-power) of terminal device 30 is excellent Choosing need to be less than or equal to 100W.If the theoretical power (horse-power) of terminal device 30 is more than 100W, equally can be by the theoretical work(of terminal device 30 Rate is divided into a grade by 25W, and correspondence increases a first comparator C13, one first diode D13 and a reference voltage Vref3, will not be described in detail herein.

In the present embodiment, voltage conversion circuit 204 be electrically connected at multiple POE port 10a, 10b, Multiple POE port 10a, 10b, 10c, 10d multiple power supply signals exported are converted to terminal device 30 by 10c, 10d Required driving voltage, with drives terminal equipment 30.In the present embodiment, voltage conversion circuit is that prior art is realized to many Individual power supply signal carries out the voltage conversion module of voltage conversion, will not be described in detail herein.

In the present embodiment, control circuit 206 is multiple and door AN1, AN2, AN3.In the present embodiment, because only with Exemplified by four POE ports 10a, 10b, 10c, 10d, therefore it is three with door AN1, AN2, AN3.Include first with door AN1 Input, the second input and output end, the first of port circuit for detecting 200 is electrically connected at door AN1 first input end Signal output part, the first diode D11 negative pole and port circuit for detecting 200 is electrically connected at door AN1 the second input Secondary signal output end.Include first input end, the second input and output end, the first input end with door AN2 with door AN2 It is electrically connected at the first diode D12 negative pole and the 3rd signal output part of port circuit for detecting 200, second with door AN2 Input is electrically connected at the first diode D13 negative pole and the 4th signal output part of port circuit for detecting 200.With door AN3 Including first input end, the second input and output end, the output with door AN1 is electrically connected at door AN3 first input end End, is electrically connected at the output end with door AN2 with door AN3 the second input, voltage is electrically connected at door AN3 output end Change-over circuit 204.It is multiple with door AN1, AN2, AN3 multiple POE port 10a, 10b, 10c, 10d export it is multiple The power of power supply signal be not less than terminal device 30 theoretical power (horse-power) when output enable signal, voltage conversion circuit 204 always according to Enable signal and judge whether to voltage conversion.Voltage conversion circuit 204 is when receiving enable signal, voltage conversion circuit 204 carry out voltage conversion, when not receiving enable signal, the break-off of voltage conversion circuit 204, voltage conversion circuit 204 Output voltage is 0.In the other embodiment of the present invention, control circuit 206 or other realization detectings are in multiple Ethernets The power of multiple power supply signals of supply port 10a, 10b, 10c, 10d output is not less than defeated during the theoretical power (horse-power) of terminal device 30 Go out to enable the chip or module of signal, such as single-chip microcomputer, PLD.

For example, it is assumed that the theoretical power (horse-power) of terminal device 30 be 60W, because each POE port 10a, 10b, 10c, 10d can provide maximum 25W output, therefore, it needs three POE ports 10a, 10b, 10c to be powered.Eventually The predeterminated voltage for the output that end equipment 30 is exported should be one and be less than 3.75V and the voltage signal more than 2.5V, because of reference voltage Vref1 is 1.25V, and reference voltage Vref 2 is 2.5V, and reference voltage Vref 3 is 3.75V, therefore first comparator C11, C12 is defeated Go out low level, first comparator C13 is output as high level.Now, it is assumed that the first sense terminal of port circuit for detecting 200, second When sense terminal, the 3rd sense terminal detect POE port 10a, 10b, 10c and can be powered, port detecting The first signal output part, secondary signal output end, the 3rd signal output part of circuit 200 are output as high level, because of the one or two The buffer action of pole pipe D11, D12, first input end, the second input with door AN1 are high level, and first with door AN2 Input is also high level.Even if port circuit for detecting does not detect POE port, 10d can be powered, because Be electrically connected at first comparator C13 output end by the first diode D13 with door AN2 the second input, thus with door AN2 The second input be similarly high level.Also it is high level with door AN3 outputs so that exporting high level with door AN1, AN2, When voltage conversion circuit 204 is detected with door AN3 output ends as high level, voltage conversion circuit 204 carries out voltage conversion, with right Terminal device 30 is powered.It can be powered when port circuit for detecting 200 only detects only two Ethernets 10a, 10b When or what is more be less than two when, because port circuit for detecting 200 the 3rd signal output part be low level and first comparator C12 Output end is low level, therefore, be low level with door AN2 first input end, its output end is also low level so that with door AN3 output ends are low level, when voltage conversion circuit 204 is detected with door AN3 output ends as low level, are turned without voltage Change, the output voltage of voltage conversion circuit 204 is 0.So as to realize control circuit 206 port circuit for detecting 200 detected with The peak power output sum for the port that can be powered in net supply port 10a, 10b, 10c, 10d very much is not less than eventually During the theoretical power (horse-power) of end equipment 30, the control output of circuit 206 enables signal, and voltage conversion circuit 204 just proceeds by voltage and turned Change.So as to realize the maximum output for the port that can be powered in POE port 10a, 10b, 10c, 10d When power sum is not less than the theoretical power (horse-power) of terminal device 30, power backup circuit 20a just starts working, it is to avoid due to Ethernet Overload phenomenon occurs for supply port 10a, 10b, 10c, 10d power supply capacity deficiency, causes the infringement to terminal device 30.

It should be noted that in the present embodiment, because assuming that the theoretical power (horse-power) of terminal device 30 is 60W, therefore port is detectd Too net supply port 10a, 10b, 10c, 10d that slowdown monitoring circuit 200 detects three or more than three can have been supplied When electric, control circuit 206, which is exported, enables signal, voltage conversion is carried out with control voltage change-over circuit 204, with to terminal device 30 are powered.Similarly, for the terminal device that theoretical power (horse-power) is 80W, port circuit for detecting 200 need to detect four or four When too net supply port 10a, 10b, 10c, 10d more than individual can be powered, control circuit 206 just exports enable Signal, voltage conversion circuit 204 just carries out voltage conversion, will not be described in detail herein.

In the present embodiment, sample circuit 208 includes sampling resistor Rs, and sampling resistor Rs one end is electrically connected at voltage Change-over circuit 204, other end ground connection.Realize that collection flows through electric current and the output of voltage conversion circuit 204 by sampling resistor Rs First sampled voltage.In the present embodiment, the first sampled voltage is voltage signal, and sampling resistor Rs is preferably precision resistance, First sampled voltage=sample rate current（Flow through the electric current of voltage conversion circuit 204）* sampling resistor Rs resistance, sampling resistor Rs resistance can be set according to actual needs.In other embodiments of the present invention, sample circuit 208 can also be Current transformer, or the sample circuit of other prior arts realize the sampling of electric current.

In the present embodiment, the bag signal amplification unit 2100 of the first dynamic sensing circuit 210, multiple second comparing units 2102a, 2102b, 2102c, multiple signal buffering circuit 2104a, 2104b, 2104c, multiple second isolated location 2106a, 2106b, 2106c and multiple switch unit 2108a, 2108b, 2108c.In the present embodiment, amplifying unit 2100 is amplification Device A1, multiple second comparing unit 2102a, 2102b, 2102c are multiple second comparator C21, C22, C23, and multiple signals are temporary Deposit circuit 2104a, 2104b, 2104c for multiple OR gate OR1, OR2, OR3, multiple second isolated location 2106a, 2106b, 2106c is multiple second diode D21, D22, D23, and multiple switch unit 2108a, 2108b, 2108c are multiple electronic switches Q1、Q2、Q3.Amplifier A1 includes positive input, reverse input end and output end, and amplifier A1 positive input electrically connects It is connected to sampling resistor Rs and voltage conversion circuit 204 common port, amplifier A1 reverse input end ground connection.Second comparator C21 includes positive input, reverse input end and output end, and the second comparator C21 positive input receives reference voltage Vref1, the second comparator C21 reverse input end are electrically connected at amplifier A1 output end, reception amplifier A1 outputs Second sampled voltage.Second comparator C222 includes positive input, reverse input end and output end.Second comparator C22's Positive input receives reference voltage Vref 2, and the second comparator C22 reverse input end is electrically connected at amplifier A1 output End, the second sampled voltage of reception amplifier A1 outputs.Second comparator C23 includes positive input, reverse input end and defeated Go out end.Second comparator C23 positive input receives reference voltage Vref 3, and the second comparator C23 reverse input end is electrical It is connected to amplifier A1 output end, the second sampled voltage of reception amplifier A1 outputs.OR gate OR1 include first input end, Second input and output end, OR gate OR1 first input end are electrically connected at the second comparator C21 output end, OR gate OR1 The second input be electrically connected at OR gate OR1 output end.OR gate OR1 output end is electrically connected at the second diode D21 Positive pole, the second diode D21 negative pole is electrically connected at the first diode D11 negative pole.OR gate OR2 includes the first input End, the second input and output end, OR gate OR2 first input end are electrically connected at the second comparator C22 output end, OR gate OR2 the second input is electrically connected at OR gate OR2 output end.OR gate OR2 output end is electrically connected at the second diode D22 positive pole, the second diode D22 negative pole is electrically connected at the first diode D12 negative pole.It is defeated that OR gate OR3 includes first Enter end, the second input and output end, OR gate OR3 first input end is electrically connected at the second comparator C23 output end, or Door OR3 the second input is electrically connected at OR gate OR3 output end.OR gate OR3 output end is electrically connected at the two or two pole Pipe D23 positive pole, the second diode D23 negative pole is electrically connected at the first diode D13 negative pole.Electronic switch Q1 includes the One end, the second end and the 3rd end, electronic switch Q1 first end are electrically connected at the public of OR gate OR1 and the second diode D21 End, electronic switch Q1 the second end is electrically connected at POE port 10b, electronic switch Q1 the 3rd end ground connection.Electronics Switching Q2 includes first end, the second end and the 3rd end, and electronic switch Q2 first end is electrically connected at OR gate OR2 and the two or two pole Pipe D22 common port, electronic switch Q2 the second end is electrically connected at POE port 10c, the 3rd of electronic switch Q2 the End ground connection.Electronic switch Q3 includes first end, the second end and the 3rd end, and electronic switch Q3 first end is electrically connected at OR gate OR3 and the second diode D23 common port, electronic switch Q3 the second end are electrically connected at POE port 10d, electronics Switch Q3 the 3rd end ground connection.When being powered by power backup circuit 20a to terminal device 30, control terminal equipment 30 is in Of short duration full load condition, the electric current that now voltage conversion circuit 204 is exported is maximum, that is, the electric current that sampling resistor Rs is collected is most Greatly, the first sampled voltage of its output is maximum.First dynamic sensing circuit 210 is according to sampling resistor Rs in terminal device 30 The first sampled voltage for being exported under full load condition exports the second control signal, thus control POE port 10a, 10b, Whether 10c, 10d need to close.So as to realize power supply signal that power backup circuit 20a provided closer to the work of terminal device 30 Make the actual demand under state.Avoid because the peak power when theoretical power (horse-power) of terminal device 30 is run with it has big difference, Cause unnecessary energy dissipation.

For example, it is assumed that the theoretical power (horse-power) of terminal device 30 is 60W, and obtains peak power during its operation for 40W.Because every One POE port 10a, 10b, 10c, 10d can provide maximum 25W output, therefore, original state, due to fixed detecting electricity First control signal of road 202a outputs, it needs three or more than three POE port 10a, 10b, 10c, 10d In that can be powered state, voltage conversion circuit is just started working.Now electronic switch Q1, Q2, Q3 the second end is High level.Lower state, fixed circuit for detecting 202a is exported without the first control signal, and control terminal equipment 30 is in of short duration full negative Lotus state, the first dynamic sensing circuit 210 obtains peak power for 40W when detecting its operation of terminal device 30, that is, amplifier A1 output the second sampled voltage for one be more than 1.25V and less than 2.5 voltage signal, because reference voltage Vref 1 be 1.25V, Reference voltage Vref 2 is that 2.5V, reference voltage Vref 3 are 3.75V, therefore the second comparator C21 output ends are low level, the second ratio It is high level compared with device C22, C23 output end.OR gate OR1 output ends are low level, and OR gate OR2, OR3 output end are high level, Even if now amplifier A1 is without exporting or changing, OR gate OR1 output ends are still low level, OR gate OR2, OR3 output end Still it is high level, is realized by OR gate OR1, OR2, OR3 and full bear is in terminal device 30 to second comparator C21, C22, C23 The second control signal exported under lotus state is kept in, when power backup circuit 204 restarts, OR gate OR1, OR2, OR3 output end voltages can just change.Because OR gate OR1 output ends are low level, OR gate OR2, OR3 output end are high level, When port circuit for detecting 200 detect POE port 10a, 10b be in can be powered state when, it is defeated with door AN1 Go out end just for high level, now, even if port circuit for detecting 200 detect that POE port 10c, 10d be not in can be with It is still high level with door AN2 output ends, so as to be output as high level with door AN3 when being powered state.So as to realize when the One dynamic sensing circuit 210 obtains peak power when detecting its operation of terminal device 30 and detected for 40W and port circuit for detecting There are two or more POE port 10a, 10b, 10c, 10d to be in the state that can be powered, control circuit 206 outputs enable signal, and voltage conversion circuit 204 is in normal operating conditions, carries out voltage conversion to enter terminal device 30 Row power supply.Because OR gate OR1, OR2, OR3 are kept in the second control signal, therefore high level is continuously with door AN3 outputs, controlled Circuit 206 processed will persistently export enable signal, and realization is persistently powered to terminal device 30.Because OR gate OR1 output ends are low Level, OR gate OR2, OR3 output end is high level, and electronic switch Q1 is not turned on, and electronic switch Q2, Q3 are both turned on, electronic switch Q2, Q3 the second end are changed into low level state from the high level of original state, are become by electronic switch Q2, Q3 the second terminal voltage Change to export shutdown signal, POE port 10c, 10d detect the shutdown signal pause work of electronic switch Q2, Q3 output Make, Non voltage output.Terminal device 30 is further detected by the first dynamic sensing circuit so as to which power backup circuit 20a is realized Required actual power demand, it is to avoid peak power when being run due to the theoretical power (horse-power) of terminal device 30 with it is had big difference, Cause unnecessary power wastage.

It should be noted that amplifier A1 can select according to actual needs its amplify multiple, electronic switch Q1, Q2, Q3 can be N-type metal oxide semiconductor field effect tube, or P-type mos FET or crystal Triode.In other embodiments of the present invention, signal amplification unit 2100 can also be realized for transistor to the One sampled voltage is amplified, or other amplifying devices.Signal temporary storage location 2104a, 2104b, 2104c can also For flip-flop or other can realize temporary device.Second comparing unit 2102a, 2102b, 2102c is alternatively other and realizes electricity Pressure ratio compared with element or module.Second isolated location 2104a, 2104b, 2104c is alternatively other elements for realizing signal isolation Or module.

It should be noted that because in the present embodiment only using four POE port 10a, 10b, 10c, 10d as Example, the control signal of power output second that can be reached when the first dynamic sensing circuit 210 is according to terminal device actual motion, too Net supply port 10a, 10b, 10c, 10d judges whether break-off according to the second control signal.In actual applications, terminal is set Standby 30 power is greater than 0W, therefore according to the second control signal, at most occur closing three too net supply port 10b, 10c, 10d situation.Therefore, in the present embodiment, electronic switch Q1, Q2, Q3 be three, equally, the second comparator C21, C22, C23, OR gate OR1, OR2, OR3, second diode D21, D22, D23 are three.And for the POE of more than four Port, one second comparator C23 of the first dynamic sensing circuit correspondence increase, OR gate OR3, the second diode D23 and electronic switch Q3, will not be described in detail herein.

Fig. 6 is the module map of the another embodiments of power backup circuit 20b of the present invention.In the present embodiment,

Power backup circuit 20b include port circuit for detecting 200, fixed circuit for detecting 202, voltage conversion circuit 204 and Micro-control unit U1.In the present embodiment, port circuit for detecting 200, fixed circuit for detecting 202 and voltage conversion circuit 204 It is similar to the port circuit for detecting 200 in Fig. 2, fixed circuit for detecting 202 and voltage conversion circuit 204, therefore be no longer described in detail.It is micro- Control unit U1 is electrically connected with port circuit for detecting 200, fixed circuit for detecting 202 and voltage conversion circuit 204, is detectd according to fixation Multiple ports signal output in place that the first control signal and port circuit for detecting 200 that slowdown monitoring circuit 202 is exported are exported enables letter Number.

As a further improvement on the present invention, power backup circuit 20b also includes the dynamic detection of sample circuit 208 and second Circuit 212, as shown in fig. 7, being the module map of the another embodiments of power backup circuit 20b of the present invention.In the present embodiment, Sample circuit 208 is similar to the sample circuit 208 in Fig. 3, therefore is no longer described in detail.Second dynamic sensing circuit 212 is electrically connected with In sample circuit 208 and micro-control unit U1, the control of the first sampled voltage output second exported according to sample circuit 208 is believed Number.The second control signal and port circuit for detecting 200 that micro-control unit U1 is exported always according to the second dynamic sensing circuit 212 are defeated The multiple ports signal output in place gone out enables signal, and whether voltage conversion is carried out with control voltage change-over circuit 204.

As a further improvement on the present invention, micro-control unit U1 be also electrically connected at multiple POE port 10a, 10b, 10c, 10d, micro-control unit U1 are controlled always according to the second control signal output the 3rd that the second dynamic sensing circuit 212 is exported Signal processed, multiple POE port 10a, 10b, 10c, 10d judge whether break-off always according to the 3rd control signal.From And realize power supply signal that power backup circuit 20b provided closer to the actual demand under the working condition of terminal device 30.

Flowed down it should be noted that the electric current that sample circuit 208 is gathered is preferably terminal device 30 in full load condition The electric current of warp, so that when multiple POE port 10a, 10b, 10c, 10d are further run according to terminal device 30 Required peak power is come the number of POE port 10a, 10b, 10c, 10d needed for determining.So as to realize that power supply is standby The power supply signal provided with circuit 20b is closer to the actual demand under the working condition of terminal device 30.

Fig. 8 is the details module map of the embodiments of power backup circuit 20b mono- in Fig. 7.In the present embodiment, power supply is standby Essentially identical with circuit 20b and power backup circuit 20b in Fig. 7, difference is, the second dynamic sensing circuit 212 is wrapped Include signal amplification unit 2122 and analog-digital converter U2.Signal amplification unit 2122 and the phase of signal amplification unit 2100 in Fig. 4 Seemingly, therefore no longer it is described in detail.Analog-digital converter U2 is electrically connected at signal amplification unit 2122 and micro-control unit U1, according to signal The second sampled voltage that amplifying unit 2122 is exported exports the second control signal and is sent to micro-control unit U1.

Fig. 9 is the physical circuit figure of the embodiments of power backup circuit 20b mono- in Fig. 8.In the present embodiment, it is fixed Circuit for detecting 202b and fixation circuit for detecting 202a in Fig. 5 is essentially identical, and difference is, fixed circuit for detecting 202b is gone First diode D11, D12, D13 is fallen, first comparator C11, C12, C13 output end are electrically connected at micro-control unit U1.Fixed circuit for detecting 202b produces the first control signal by first comparator C11, C12, C13 and is sent to microcontroller list First U1, in other embodiments of the present invention, fixed circuit for detecting 202b can not also remove the first diode D11, D12, D13.The second sampled voltage that analog-digital converter U2 exports amplifier A1 carries out analog-to-digital conversion and exports the second control signal, with The maximum that can be reached when making the second sampled voltage that micro-control unit U1 is exported according to amplifier A1 run terminal device 30 Power carries out power grade identification and exports the 3rd control signal, to control POE port 10a, 10b, 10c, 10d to be It is no to be powered, unwanted POE port 10a, 10b, 10c, 10d are closed so as to realize.

Figure 10 is the flow chart in the embodiment of POE method one of the present invention.First, in step S1000, end Multiple power supply signals correspondence that mouth circuit for detecting 200 is exported according to multiple POE port 10a, 10b, 10c, 10d is exported Multiple port signals in place.In step S1002, fixed circuit for detecting 202 is according to the predeterminated voltage of terminal device 30 output the One control signal.In step S1004, the first control signal and end that control circuit 206 is exported according to fixed circuit for detecting 202 Multiple ports signal output in place that mouth circuit for detecting 200 is exported enables signal.In step S1006, voltage conversion circuit 204 According to whether the enable signal for receiving the control output of circuit 206 judges whether to voltage conversion, voltage conversion circuit 204 exists When receiving enable signal, voltage conversion is carried out, when not receiving enable signal, break-off.

Figure 11 is the details flow chart in the embodiment of POE method one in Figure 10.In present embodiment flow chart In step S1100, S1102, S1104, S1112 and Figure 10 in flow chart step S1000, S1002, S1004, S1006 One-to-one corresponding is similar, thus is no longer described in detail.In step S1106, the first dynamic sensing circuit 210 is defeated according to sample circuit 208 The first sampled voltage gone out exports the second control signal.In step S1108, control circuit 206 is always according to the first dynamic detection Multiple ports signal output in place that the second control signal and port circuit for detecting 200 that circuit 210 is exported are exported enables signal. In step S1110, multiple POE port 10a, 10b, 10c, 10d are exported according to the first dynamic sensing circuit 210 Second control signal judges whether break-off.

Figure 12 is the flow chart of another embodiment of POE method of the present invention.In present embodiment flow chart Step S1200, S1202, S1206 are similar to step S1000, S1002, S1006 one-to-one corresponding of the flow chart in Figure 10, thus No longer it is described in detail.In step S1204, the first control signal and end that micro-control unit U1 is exported according to fixed circuit for detecting 202 Multiple ports signal output in place that mouth circuit for detecting 200 is exported enables signal.

Figure 13 is the details flow chart of the embodiment of POE method one in Figure 12.In present embodiment flow chart Step S1300, S1302, S1314 it is similar to step S1000, S1002, S1006 one-to-one corresponding of the flow chart in Figure 10, because And be no longer described in detail.Step S1304 in flow chart is similar to the step S1204 of the flow chart in Figure 12, thus is no longer described in detail. In step S1306, the first sampled voltage output second that the second dynamic sensing circuit 212 is exported according to sample circuit 208 is controlled Signal.In step S1308, the second control signal that micro-control unit U1 is exported always according to the second dynamic sensing circuit 212 and Multiple ports signal output in place that port circuit for detecting 200 is exported enables signal.In step S1310, micro-control unit U1 The 3rd control signal is exported always according to the second control signal that the second dynamic sensing circuit 212 is exported.It is many in step S1312 The 3rd control signal that individual POE port 10a, 10b, 10c, 10d is exported according to micro-control unit U1 judges whether pause Work.

Claims

1. a kind of power backup circuit, for multiple POE ports are in parallel with drives terminal equipment, it is characterised in that The power backup circuit includes：

Port circuit for detecting, for being electrically connected at the multiple POE port, for according to the multiple Ethernet The multiple port signals in place of multiple power supply signals correspondence output of supply port output；

Fixed circuit for detecting, the predeterminated voltage for being exported according to the terminal device exports the first control signal, wherein, it is described Fixed circuit for detecting includes：First comparison circuit, including multiple first comparing units, for according to the default of the terminal device Voltage and multiple control signals of reference voltage output first；

Voltage conversion circuit, for being electrically connected at the multiple POE port, for the multiple Ethernet to be supplied Multiple power supply signals of electric port output are converted to the driving voltage needed for the terminal device, to drive the terminal device； And

Circuit is controlled, for receiving first control signal from the fixed circuit for detecting and the port circuit for detecting respectively With the multiple port signal in place, and enabled and believed according to first control signal and the multiple port signal output in place Number to the voltage conversion circuit；

Wherein, the voltage conversion circuit is additionally operable to judge whether to voltage turn according to whether receiving the enable signal Change.

2. power backup circuit as claimed in claim 1, it is characterised in that the predeterminated voltage is that the terminal device is theoretical The corresponding voltage of power.

3. power backup circuit as claimed in claim 2, it is characterised in that the fixed circuit for detecting also includes：

First isolation circuit, one end is electrically connected with first comparison circuit, and the other end is electrically connected at the port detecting electricity Road and the common port of the control circuit, first isolation circuit includes multiple first isolated locations, for isolating described the One comparison circuit and the port circuit for detecting, so that multiple ports signal in place of port circuit for detecting output is sent to The control circuit；

Wherein, the multiple first isolated location is corresponded with the multiple first comparing unit and is electrically connected with.

4. power backup circuit as claimed in claim 1, it is characterised in that also including sample circuit, for being electrically connected with Voltage conversion circuit is stated, the electric current of the voltage conversion circuit is flowed through for gathering and the first sampled voltage is exported.

5. power backup circuit as claimed in claim 4, it is characterised in that the electric current of the sample circuit collection is the end End equipment is in the electric current flowed through under full load condition.

6. power backup circuit as claimed in claim 4, it is characterised in that also including the first dynamic sensing circuit, for electricity Property the connection sample circuit, the control circuit and the multiple POE port, for according to the sample circuit First sampled voltage of output exports the second control signal, and the control circuit is additionally operable to according to second control signal and institute State multiple ports signal output in place and enable signal to control whether the voltage conversion circuit carries out voltage conversion, it is the multiple POE port judges whether break-off always according to second control signal.

7. the power backup circuit as described in claim 1 or 6, it is characterised in that the voltage conversion circuit is receiving When stating enable signal, the voltage conversion circuit carries out voltage conversion, to drive the terminal device, and described make is not being received During energy signal, the voltage conversion circuit break-off, the voltage conversion circuit output voltage is 0.

8. power backup circuit as claimed in claim 6, it is characterised in that first dynamic sensing circuit includes：

Signal amplification unit, the first sampled voltage for the sample circuit to be exported carries out signal amplification, to obtain second Sampled voltage；

Second comparison circuit, including multiple second comparing units, for according to second sampled voltage and multiple reference voltages Export the second control signal of second comparison circuit；

Signal buffering circuit, including multiple signal temporary storage locations, the second control signal for keeping in second comparison circuit；

Second isolation circuit, one end is electrically connected at the signal buffering circuit, and the other end is electrically connected at the port detecting The common port of circuit and the control circuit, second isolation circuit includes multiple second isolated locations, described for isolating Signal buffering circuit and the port circuit for detecting, so that the signal transmission in place of multiple ports of port circuit for detecting output To the control circuit；And

On-off circuit, for being electrically connected at the signal buffering circuit, including multiple switch unit, for according to described second Second control signal of comparison circuit exports multiple shutdown signals；

Wherein, the multiple POE port judges whether break-off always according to the multiple shutdown signal, described many Individual second comparing unit, multiple signal temporary storage locations, multiple second isolated locations and multiple switch unit, which are corresponded, electrically to be connected Connect.

9. power backup circuit as claimed in claim 8, it is characterised in that the multiple first comparing unit with it is the multiple The quantity of second comparing unit is than the quantity few one of the multiple POE port, the multiple POE port Multiple power supply signals of multiple power grades are exported, each reference voltage is the voltage of correspondence power grade.

10. power backup circuit as claimed in claim 9, it is characterised in that every one first comparing unit is used for relatively more described The reference voltage of predeterminated voltage and the corresponding power grade of terminal device output simultaneously exports comparative result signal, and described first controls Signal is multiple comparative result signals that the multiple first comparing unit is exported.

11. power backup circuit as claimed in claim 9, it is characterised in that the control circuit includes multiple and door, described The power of multiple multiple power supply signals exported with door in the multiple POE port is not less than the terminal device Output enables signal during theoretical power (horse-power).

12. power backup circuit as claimed in claim 9, it is characterised in that every one second comparing unit is used for relatively more described The reference voltage of second sampled voltage and corresponding power grade simultaneously exports comparative result signal, and the second of second comparison circuit Control signal is multiple comparative result signals that the multiple second comparing unit is exported.

13. power backup circuit as claimed in claim 12, it is characterised in that the multiple switch element is used for according to described Multiple multiple shutdown signals of comparative result signal output of multiple second comparing unit outputs.

14. power backup circuit as claimed in claim 13, it is characterised in that each POE port is being received pair During the shutdown signal of inductive switch unit output, break-off, the voltage of the power supply signal of output is 0.

15. power backup circuit as claimed in claim 4, it is characterised in that the control circuit includes microcontroller.

16. power backup circuit as claimed in claim 15, it is characterised in that also including the second dynamic sensing circuit, be used for The sample circuit and the micro-control unit are electrically connected with, the first sampled voltage for being exported according to the sample circuit is defeated Go out the second control signal, the micro-control unit is additionally operable to according to second control signal and the multiple port signal in place Output enables signal, to control whether the voltage conversion circuit carries out voltage conversion.

17. power backup circuit as claimed in claim 16, it is characterised in that the micro-control unit is also electrically connected at institute Multiple POE ports are stated, the micro-control unit is additionally operable to according to the control letter of second control signal output the 3rd Number, the multiple POE port judges whether break-off always according to the 3rd control signal.

18. power backup circuit as claimed in claim 16, it is characterised in that second dynamic sensing circuit includes：

Signal amplification unit, the first sampled voltage for the sample circuit to be exported carries out signal amplification, to obtain second Sampled voltage；And

Analog-digital converter, for exporting the second control signal according to second sampled voltage.

19. a kind of POE system, it is characterised in that including：

Multiple POE ports；

Terminal device；And

Power backup circuit as any one of claim 1-18.

20. a kind of POE method, in the power backup circuit of POE system by multiple POEs Port is in parallel with drives terminal equipment, and the power backup circuit includes port circuit for detecting, fixed circuit for detecting, voltage conversion Circuit and control circuit, it is characterised in that the POE method comprises the following steps：

Multiple power supply signals correspondence output that the port circuit for detecting is exported according to the multiple POE port is multiple Port signal in place is to the control circuit；

The fixed circuit for detecting is according to the predeterminated voltage of the terminal device and multiple control signals of reference voltage output first To the control circuit；

The control circuit enables signal to described according to first control signal and the multiple port signal output in place Voltage conversion circuit；And

The voltage conversion circuit judges whether to voltage conversion according to whether receiving the enable signal.

21. POE method as claimed in claim 20, it is characterised in that the power backup circuit also includes sampling Circuit and the first dynamic sensing circuit, wherein the control circuit is in place according to first control signal and the multiple port The step of signal output enables signal includes：The control circuit is in place according to first control signal and the multiple port Signal output enable signal to the control circuit, first dynamic sensing circuit exported according to the sample circuit first Sampled voltage exports the second control signal, and the control circuit is in place always according to second control signal and the multiple port Signal output enables signal to the control circuit.

22. POE method as claimed in claim 21, it is characterised in that the control circuit is according to the described first control The step of signal processed and the multiple port signal output in place enable signal also includes：The multiple POE port is also Break-off is judged whether according to second control signal.

23. POE method as claimed in claim 20, it is characterised in that the control circuit includes microcontroller list Member, the control circuit enables signal to the electricity according to first control signal and the multiple port signal output in place The step of voltage conversion circuit, includes：The micro-control unit is according to first control signal and the multiple port signal in place Output enable signal to the voltage conversion circuit.

24. POE method as claimed in claim 23, it is characterised in that the power backup circuit also includes sampling Circuit and the second dynamic sensing circuit, the micro-control unit are believed in place according to first control signal and the multiple port Number output enable signal the step of include：The micro-control unit is in place according to first control signal and the multiple port Signal output enables signal, and the first sampled voltage that second dynamic sensing circuit export according to the sample circuit exports the Two control signals, the micro-control unit is enabled always according to second control signal and the multiple port signal output in place Signal.

25. POE method as claimed in claim 24, it is characterised in that the micro-control unit is according to described first The step of control signal and the multiple port signal output in place enable signal also includes：The micro-control unit is always according to institute State the second control signal and export the 3rd control signal, the multiple POE port is sentenced always according to the 3rd control signal It is disconnected whether break-off.

26. POE method as claimed in claim 20, it is characterised in that the voltage conversion circuit is according to whether receive The step of judging whether to voltage conversion to the enable signal includes：The voltage conversion circuit is receiving the enable During signal, the voltage conversion circuit carries out voltage conversion, when not receiving the enable signal, the voltage conversion circuit Break-off, the voltage conversion circuit output voltage is 0.