CN206640591U - A kind of simple compatible POE electric supply installations - Google Patents

Abstract

The utility model discloses a kind of simple compatible POE electric supply installations, including power supply terminal circuit and receiving end circuit, power and be attached between terminal circuit and receiving end circuit by network transformer and netting twine；Power supply terminal circuit includes the first circuit for detecting, power supply circuit, logic circuit and the second circuit for detecting；Receiving end circuit includes rectification circuit, detecting resistance and on-off circuit.The utility model forms circuit using better simply discrete device, it can accomplish that reliable recognition is powered without special chip, the power supply circuit of enough compatibility standard PSE or the PD equipment of and can simultaneously, so that in the case where keeping relatively low cost, while meet that PSE the and PD equipment of compatibility standard carries out supplying powered requirement.With the advantages of good reliability, flexibility is strong.

Description

A kind of simple compatible POE electric supply installations

Technical field

It the utility model is related to POE（POE）Technical field, specifically a kind of simple compatible POE power supply dresses Put.

Background technology

POE (Power Over Ethernet) refers to not appointing in existing Ethernet Cat.5 wirings architecture In the case that what is changed, for some IP-based terminals（Such as IP telephone machine, wireless local network connecting point AP, web camera Deng）While transmitting data-signal, moreover it is possible to which the technology of direct current supply is provided for this kind equipment.POE is also referred to as based on LAN Electric power system (POL, Power over LAN) or active Ethernet (Active Ethernet), be also called for short sometimes POE, this is the newest standards rule that data and electrical power are transmitted while utilizing existing standard Ethernet transmission cable Model, and maintain the compatibility with existing Ethernet system and user.Power supply identification process disclosure satisfy that IEEE 802.3af are marked Accurate or IEEE 802.3at standards.

Comparative maturity, a complete electric power system POE include power supply end equipment to traditional POE solutions（PSE, Power Sourcing Equipment）With receiving end equipment（PD, Power Device）Two parts, there is special chip energy Complete the functions such as effective identification between PSE device and PD equipment, classification, power supply.PSE device is for ethernet client equipment The equipment of power supply, while be also the manager of whole POE POEs process, and PD equipment is to receive the PSE loads of power supply. Traditional POE system is used in combination using PSE chips and PD chips more, electricity of the PSE device in port output very little Pressure, until it detects the receiving end equipment for a support IEEE 802.3af standard of cable terminations connection.When detecting After receiving end equipment PD, PSE device can be that PD equipment is classified, and assess the power attenuation needed for this PD equipment.Point Reliable and stable 48V direct current is provided PD equipment after class is complete.But some with scenes, for example privately owned be System, host A are powered by netting twine to slave B, but only for enabling host B to be powered by standard PSE device, or main frame energy It is enough that standard PD equipment is powered, if user according to traditional POE power supply modes, if using expensive PSE chips and PD chips, Cost is often much more, and form is complex.

Publication No. is CN103779972A, and publication date provides one kind for 2014-05-07 Chinese invention patent and simply may be used The POE device leaned on, the basic implementation method of the patent of invention are：The feature detection resistance of receiving end equipment passes through two The detection circuit of power supply end equipment is connected to ethernet line, when the detection electric circuit inspection of power supply end equipment is to the receiving end connected When the detecting resistance of equipment meets the requirements, that is, think to be connected to legitimate device, end equipment of then powering passes through except connection The two further pairs ethernet line of detecting resistance is powered to receiving end equipment.The patent is only identified using only resistance, into This is relatively low, but can not accomplish other compatible PSE or PD equipment.

Utility model content

The purpose of this utility model is to provide a kind of simple compatible POE electric supply installations, and it can keep relatively low cost Under, while meet that PSE the and PD equipment of compatibility standard carries out supplying powered requirement.

To achieve these goals, the utility model adopts the following technical scheme that：

A kind of simple compatible POE electric supply installations, including power supply terminal circuit and receiving end circuit, power supply terminal circuit with by electricity It is attached between terminal circuit by network transformer and netting twine；

Power supply terminal circuit includes the first circuit for detecting, power supply circuit, logic circuit and the second circuit for detecting；Logic circuit bag Include logic or circuit；The input of power supply circuit is connected to power input by the current sampling resistor of the second circuit for detecting, The output end of power supply circuit connects the sampling input of the first circuit for detecting and the centre cap input of network transformer respectively, The output end of first circuit for detecting and the output end of the second circuit for detecting are respectively connecting to the respective input of logic or circuit, patrol Volume or circuit output end connection power supply circuit control terminal；

Receiving end circuit includes rectification circuit, detecting resistance and on-off circuit；The input connection network of rectification circuit becomes The centre cap output end of depressor, the output end of rectification circuit connect the sampling input and on-off circuit of detecting resistance respectively Input, detect the control terminal of the sampled output connecting valve circuit of resistance；The sampling input of first circuit for detecting passes through Netting twine is connected with detecting the sampling input of resistance；The output end of on-off circuit is the output end of receiving end circuit.

The logic circuit also includes delay circuit, the delay circuit be connected to the output end of the logic or circuit with Between the control terminal of the power supply circuit.

The logic or circuit use OR gate, or use two diodes in parallel in the same direction, and this two diodes Anode is the respective input of the logic or circuit, and the negative electrodes of this two diodes collectively forms the logic or circuit Output end.

Amplifier U1 of second circuit for detecting by current sampling resistor R4 and with certain multiplication factor is formed, and electric current is adopted Sample resistance R4 both ends are respectively connecting to amplifier U1 respective input, and amplifier U1 output end is connected to the corresponding of logic or circuit Input.

After such scheme, a kind of simple compatible POE electric supply installations of the present utility model, because standard POE powers Power supply process be PSE end equipments by detecting the specific electrical resistance in PD equipment（It is exactly to detect resistance in the present apparatus）To identify Satisfactory PD equipment, hierarchical identification is carried out to PD equipment by specific detecting voltage again after identification, if PD is to this point Level identification does not respond especially（Such as keep detecting resistance）Classification 0 will be so considered by PSE device, can normally be supplied Electricity, in the present apparatus, PD parts utilize this characteristic, and the resistance of detecting resistance is remained in reconnaissance phase PD parts, because This can be with the PSE device of compatibility standard, so as to be powered by standard PSE device.And due to there is this detecting in the PD equipment of standard Resistance, therefore the PSE parts of the present apparatus can be by detecting the resistance, so as to as standard PSE device, to standard PD It is powered, so as to which compatible POE standards can be realized, you can powered or standard PD equipment is powered by standard PSE device.Together When, in the utility model, in original first circuit for detecting（Resistance detecting circuit）On the basis of increase by the second circuit for detecting（Electric current Detect circuit）, after the first circuit for detecting detects legitimate device and successfully powers, make use of the second circuit for detecting combination logic Or the function of circuit so that after resistance failure is detected caused by being powered to legal power receiving equipment, power supply is continued.So as to Solving existing discrete power supply technique detection cable and power cable on circuit needs separated contradiction, it is only necessary to two pairs of netting twines （A pair of netting twines are feeder ear positive pole, and a pair of netting twines are feeder ear negative pole, while play the function of detection and the function of power supply）Just Detection and power supply of the power supply end equipment to receiving end equipment can be realized.The utility model uses better simply discrete device structure Into circuit, it can accomplish that reliable recognition is powered without special chip, while the power supply of enough compatibility standard PSE or the PD equipment of and can Circuit, so that in the case where keeping relatively low cost, while meet that PSE the and PD equipment of compatibility standard carries out supplying powered requirement.Tool There is the advantages of good reliability, flexibility is strong.

Brief description of the drawings

Fig. 1 is schematic block circuit diagram of the present utility model；

Fig. 2 is the circuit theory diagrams of power supply terminal circuit in Fig. 1；

Fig. 3 is the circuit theory diagrams of receiving end circuit in Fig. 1.

Embodiment

A kind of simple compatible POE electric supply installations of the present utility model, as shown in Figure 1, Figure 2 and Figure 3, including feeder ear electricity Road and receiving end circuit, power and be attached between terminal circuit and receiving end circuit by network transformer and a pair of netting twines.

Terminal circuit of powering includes the first circuit for detecting 1, power supply circuit 2, the circuit for detecting 4 of logic circuit 3 and second；Wherein, Logic circuit 3 includes logic or circuit 31.The current sampling resistor R4 that the input of power supply circuit 2 passes through the second circuit for detecting 4 Power input is connected to, the output end of power supply circuit 2 connects the sampling input and network transformation of the first circuit for detecting 1 respectively The output end of the centre cap input of device, the output end of the first circuit for detecting 1 and the second circuit for detecting 4 is respectively connecting to logic The control terminal of the output end connection power supply circuit 2 of the respective input of logic or circuit 31 in circuit 3, logic or circuit 31.

Receiving end circuit includes rectification circuit 5, detecting resistance 6 and on-off circuit 7；The input connection net of rectification circuit 5 The centre cap output end of network transformer, the output end of rectification circuit 5 connect the sampling input and switch of detecting resistance 6 respectively The input of circuit 7, detect the control terminal of the sampled output connecting valve circuit 7 of resistance 6；The sampling of first circuit for detecting 1 Input is connected by a pair of netting twines with detecting the sampling input of resistance 6（Another pair netting twine is earth-return, and affirmative also has company Connect each module, including the first circuit for detecting 1）；The output end VOUT of on-off circuit 7 is the output end of receiving end circuit.

Further, logic circuit 3 also includes delay circuit 32, and the delay circuit 32 is connected to the logic or circuit Between 31 output end and the control terminal of the power supply circuit 2.

Power supply circuit 2 is made up of PMOS Q3, resistance R10, resistance R11, NPN triode Q4.Resistance R10 and resistance R11 Series connection, one end that resistance R10 is not connected with resistance R11 connects PMOS Q3 S poles respectively（Source electrode）And current sampling resistor R4 one end, current sampling resistor R4 other end connection power input POWER_IN, PMOS Q3 D poles（Drain electrode）To supply The power output end POWER_OUT of circuit 2, and PMOS Q3 G poles（Grid）It is connected to resistance R10 and resistance R11 public affairs End altogether；The other end connection NPN triode Q4 of resistance R11 colelctor electrode, NPN triode Q4 emitter stage connect signal ground, The output end of NPN triode Q4 base stage connection delay circuit 32.When NPN triode Q4 base stage input low level, NPN tri- Pole pipe Q4 stoppings, now series resistance R10 and R11 do not flow through electric current, resistance R10 both end voltages are 0, i.e. PMOS Q3 Grid and source electrode between voltage be 0, PMOS Q3 is remained turned-off, the not supplying power for outside of power supply circuit 2；When NPN triode Q4's During base stage input high level, triode Q4 saturation conductions, power supply POWER_IN (ignoring sampling resistor R4) passes through series resistance R10 After R11 partial pressures, certain voltage is obtained between PMOS Q3 grid and source electrode（More than cut-in voltage）, PMOS Q3 beats Open supply access, the supplying power for outside of power supply circuit 2.In above-mentioned, in the form of the composition of power supply circuit 2, include but are not limited to by PMOS Q3 is formed, and PMOS Q3 can be replaced with to the DC-DC with enabled pin and formed.

Second circuit for detecting 4 is made up of amplifier U1 and current sampling resistor R4, current sampling resistor R4 both ends difference Amplifier U1 respective input is connected to, amplifier U1 output end is connected to an input of logic or circuit 31.Electric current is adopted The voltage at sample resistance R4 both ends is V4, and amplifier U1 is the amplifier with certain multiplication factor.When power supply circuit 2 is to receiving end equipment During power supply, sampling resistor R4 can flow through certain electric current, and certain voltage V4 is produced at both ends.Voltage V4 passes through amplifier U1's Amplification, produce high level and be input in logic or circuit 31；When sampling resistor R4 electric current is close to 0 or equal to 0, voltage V4 passes through After amplifier U1 amplifications, produce low level and be input in logic or circuit 31.

First circuit for detecting 1 includes window comparator, resistance R9, resistance R12, the resistance of two amplifier U2A and U2B compositions R15, resistance R6 and resistance R8.Resistance R9, resistance R12 and resistance R15 are sequentially connected in series between power end and ground, there is provided window The reference voltage V1 and V2 of comparator, wherein resistance R9 and resistance R12 common port provide V2 reference voltages, resistance R12 and Resistance R15 common port provides V1 reference voltages.Resistance R9 and resistance R12 common port is connected to the same mutually defeated of amplifier U2A Enter end, resistance R12 and resistance R15 common port is connected to amplifier U2B inverting input, amplifier U2A inverting input and Amplifier U2B in-phase input end is commonly connected to the power output end of power supply circuit 2（PMOS Q3 drain electrode）, the window compares The output end of device is connected to another input of logic or circuit 31.Amplifier U2A inverting input and amplifier U2B same phase Input is the sampling input of the window comparator, and the sampling input terminal voltage is V3, works as V1<V3<During V2, comparator U2A and U2B outputs are high level, work as V3>V2 or V3<When V1, the one of output of amplifier U2A and U2B is low electricity Flat, another is high level.Because two amplifiers are all open-drain outputs, output is by common pull-up resistor R8 short circuits one Rise, constitute the logical relation with door, therefore work as V3>V2 or V3<During V1, another amplifier of amplifier output high level is defeated Go out low level, by with logical relation, window comparator can export low level, work as V1<V3<During V2, two amplifiers export High level, window comparator can export high level.The resistance R1 and resistance R2 is the detecting resistance 6 in receiving end circuit, is supplied Electric terminal circuit is connected by a pair of netting twines with the detecting resistance 6 of receiving end circuit（Another pair netting twine is earth-return）, resistance R1 with Resistance R2 is in series, the sampling input of resistance R1 other end connection window comparator, resistance R2 other end ground connection.Power supply Terminal circuit sets detecting 6 due resistance of resistance in receiving end circuit by resistance R9, resistance R12, resistance R15 and resistance R6 Be worth scope, only when the resistance of the detecting resistance 6 falls in due scope, can just be powered terminal circuit be identified as it is legal by electricity End equipment.In Fig. 2, VCC is connected by resistance R6 with resistance R1, resistance R2, and V3 is obtained in resistance R6 and resistance R1 common port Voltage.When detecting the resistance of resistance 6 in set scope, obtained V3 voltages meet V1<V3<V2；When detecting resistance 6 Resistance is not in set scope, obtained V3 voltages V3>V2 or V3<V1.When feeder ear electric circuit inspection to legitimate device When, described window comparator exports high level to logic or circuit 31.When power supply end equipment can't detect legal receiving end During equipment, window comparator exports low level to logic or circuit 31.

In logic circuit 3, logic or circuit 31 can use OR gate, can also using two diodes in the same direction in parallel come Complete the function of logic sum gate.When using two diodes, the anode of this two diodes is logic or the phase of circuit 31 Input is answered, the negative electrode of this two diodes collectively forms logic or the output end of circuit 31.Delay circuit 32, or perhaps letter Easy monostable flipflop circuit, can be made up of simple RC components or can realize the circuit of monostable trigger function, should Effective high level that circuit can enable logic or circuit 31 export is kept for a period of time, it is ensured that the first circuit for detecting 1 and the The linking stabilization function of two circuit for detecting 4.When logic or circuit 31 have an input（Input A or input B）For height Level, then the output end F of logic or circuit 31 is high level, and delay circuit also exports high level, so that NPN triode Q4 Saturation conduction, PMOS Q3 open supplying channels, i.e. feeder ear is powered to receiving end equipment；When logic or the input of circuit 31 （Input A or input B）Be for low level when, logic or circuit 31 output be low level so that NPN triode Q4 Stopping, PMOS Q3 close supplying channels, and power supply end equipment is not powered to receiving end equipment.

Rectification circuit 5 ensure that either PSE1 with respect to PSE2 for just using the rectifier bridge D4 being made up of four diodes Voltage or negative voltage, after rectifier bridge D4, rectifier bridge D4 the 2nd pin can be positive voltage with respect to the 4th pin.Reason is The netting twine of connection power supply end equipment and receiving end equipment there may exist crossover network cables, therefore rectifier bridge D4 ensure that and either mark Accurate PSE device or the power supply end equipment of oneself, it can be powered with correct polarity for receiving end equipment.It is if privately owned System, there are the power supply polarity and netting twine of determination, can be without using rectification circuit 5.

Detecting resistance 6 is in series by resistance R1 and resistance R2, and resistance R1 and resistance R2 common port is connected to switch The control terminal of circuit 7, resistance R1 other end connection rectifier bridge D4 the 2nd pin, resistance R2 other end connection rectifier bridge D4 The 4th pin.Resistance R16 and resistance R17 is connected with certain ratio so that when terminal circuit of powering is not powered, VCC voltages warp Crossing resistance R6, resistance R1, resistance R2 partial pressure, the voltage at resistance R1 both ends can not meet the condition for opening on-off circuit 7, from And make receiving end design impedance holding resistance R1 and resistance R2 series value；And when terminal circuit of powering is powered, input power POWER_IN enters receiving end circuit by power supply circuit 2, can by the resistance R1 and resistance R2 of receiving end circuit partial pressure So that R1 both end voltages meet the condition that on-off circuit 7 is opened, so as to successfully be powered for receiving end equipment application circuit.

On-off circuit 7 is made up of PMOS Q5, PMOS Q5 source electrode connection rectifier bridge D4 the 2nd pin, PMOS Q5 Drain electrode be on-off circuit 7 output end（For load supplying）, PMOS Q5 grid（The control terminal of on-off circuit 7）Connection Resistance R1 and resistance R2 common port.When resistance R1 both end voltages meet certain value, PMOS Q5 can be opened as load electricity Road powers so that after sampling resistor R4 flows through a certain amount of electric current in power supply terminal circuit, the second circuit for detecting 4 output high level. The form of on-off circuit 7 is not limited only to PMOS Q5 form, such as the EN of DC-DC power source chip can also be utilized to enable pin and be connected on R1 and R2 common port.Following purpose can be realized：When first circuit for detecting 1 works, under VCC voltages, by resistance After R6, resistance R1, resistance R2 series connection partial pressure, receiving end circuit keeps not powering to the load.Only in power input POWER_IN voltage, by resistance R1 and resistance R2 partial pressures, can make receiving end after power supply circuit 2 accesses receiving end Circuit is opened and powered to the load.

Operation principle of the present utility model is as follows：

Before not accessing receiving end equipment, because power supply circuit 2 is opened a way, the electric current for flowing through current sampling resistor R4 is unsatisfactory for setting Definite value, therefore the second circuit for detecting 4 exports low level to logic or circuit 31；The now output end POWER_OUT of power supply circuit 2 Impedance for infinity, be unsatisfactory for due value range, therefore the first circuit for detecting 1 exports low level to logic or circuit 31. At this time the input A and input B of logic or circuit 31 are low level, therefore the output of logic or circuit 3 is low electricity It is flat, make NPN triode Q4 stoppings, PMOS Q3 closes supplying channels.Before i.e. non-access device, the He of the first circuit for detecting 1 The output of second circuit for detecting 4 is low level, and logic or circuit 3 export low level.NPN triode Q4 keeps stopping, PMOS Q3 remains turned-off supplying channels.

After accessing illegal receiving end equipment, that is, detect the scope that resistance 6 is unsatisfactory for requiring.Because of detecing for illegal receiving end equipment Measuring resistance 6 is unsatisfactory for desired scope, therefore the first circuit for detecting 1 continues to keep low level output.And PMOS Q3 is being accessed Before power receiving equipment and after access power receiving equipment, never opened, so the second circuit for detecting 4 also continues to keep low level defeated Go out, therefore logic or circuit 31 continue to output low level, NPN triode Q4 keeps stopping, and PMOS Q3 remains turned-off confession Electric channel, i.e. illegality equipment can not be powered all the time.

After accessing legal receiving end equipment, that is, detect resistance 6 and meet required scope.Because the legitimate device of access is detectd Measuring resistance 6 is in the range of requiring, the first circuit for detecting 1 output high level.The input of one end of logic or circuit 31 is high level, Therefore its output be also high level so that NPN triode Q4 saturation conductions, PMOS Q3 opening supplying channels, i.e., feeder ear to Receiving end equipment is powered.While power supply, the V3 voltages become supply voltage, and V3 is unsatisfactory for V1<V3<V2, therefore first detects Slowdown monitoring circuit 1 exports low level, but the PMOS Q3 opened causes receiving end circuit to be met the voltage of requirement and unlatching On-off circuit 7, current sampling resistor R4 flow through certain electric current, and the second circuit for detecting 4 exports high level to logic or circuit 31, So that in the case of the first circuit for detecting is low level, due to the high level of the second circuit for detecting output, logic or circuit 31 are protected Hold high level output so that NPN triode Q4 still saturation conductions, PMOS Q3 stay open supplying channels, i.e., feeder ear to Legal receiving end equipment continued power.First circuit for detecting 1 and the second circuit for detecting 4 are when switching high level, in order to keep supplying The stabilization of electricity, adds delay circuit 32 in logic circuit 3（Simple single-shot trigger circuit）.Even if delay circuit 32 causes After first circuit for detecting 1 output high level becomes low level, logic circuit 3 can keep the regular hour to export high level, should Time is enough the high level for making the output of the second circuit for detecting 4 stable, so as to realize that logic circuit 3 is defeated when inserting legitimate device Go out stable high level, power supply circuit keeps stable power supply to legal power receiving equipment.

Claims (4)

1. a kind of simple compatible POE electric supply installations, including power supply terminal circuit and receiving end circuit, power terminal circuit and receiving end It is attached between circuit by network transformer and netting twine；It is characterized in that：

Power supply terminal circuit includes the first circuit for detecting, power supply circuit, logic circuit and the second circuit for detecting；Logic circuit includes patrolling Volume or circuit；The input of power supply circuit is connected to power input by the current sampling resistor of the second circuit for detecting, power supply The output end of circuit connect respectively the first circuit for detecting sampling input and network transformer centre cap input, first The output end of circuit for detecting and the output end of the second circuit for detecting are respectively connecting to the respective input of logic or circuit, logic or The control terminal of the output end connection power supply circuit of circuit；

Receiving end circuit includes rectification circuit, detecting resistance and on-off circuit；The input connection network transformer of rectification circuit Centre cap output end, the output end of rectification circuit connects the input of the sampling input and on-off circuit of detecting resistance respectively End, secondly output end is negative pole, detects the control terminal of the sampled output connecting valve circuit of resistance；First circuit for detecting Sampling input is connected by netting twine with detecting the sampling input of resistance；The output end of on-off circuit is receiving end circuit Output end.

A kind of 2. simple compatible POE electric supply installations according to claim 1, it is characterised in that：The logic circuit is also Including delay circuit, the delay circuit be connected to the output end of the logic or circuit and the power supply circuit control terminal it Between.

A kind of 3. simple compatible POE electric supply installations according to claim 1, it is characterised in that：The logic or circuit Using OR gate, or using two diodes in parallel in the same direction, and the anode of this two diodes is the logic or circuit Respective input, the negative electrode of this two diodes collectively forms the logic or the output end of circuit.

A kind of 4. simple compatible POE electric supply installations according to claim 1, it is characterised in that：The second detecting electricity Routing current sampling resistor R4 and the amplifier U1 compositions with certain multiplication factor, current sampling resistor R4 both ends are respectively connecting to Amplifier U1 respective input, amplifier U1 output end are connected to the respective input of logic or circuit.