Summary of the invention
The present invention provides a kind of anti-reverse connection circuit of direct current power supply with self-test interlocking anti-interference function, at least to solveIn the related technology based on the anti-reverse connection circuit of direct current power supply of controllable switch unit due to voltage fluctuation the low problem of reliability.
The embodiment of the invention provides a kind of anti-reverse connection circuit of direct current power supply, comprising: direct-flow input end, DC output end,Controllable switch unit, the first partial pressure unit, isolated location, Switching Power Supply and the second partial pressure unit, wherein the first partial pressure unit connectsIt connects between direct-flow input end and common end, and draws the first partial pressure end；The input terminal of Switching Power Supply is connect with direct-flow input end；Second partial pressure unit is connected between the output end of Switching Power Supply and common end, and draws the second partial pressure end；Controllable switch unitControl terminal and first point of press bond, the first switch end of controllable switch unit connect with DC output end, controllable switch listThe second switch end of member is connect with common end；One end of isolated location and the control terminal of controllable switch unit connect, isolated locationThe other end and second point of press bond, isolated location be used for be isolated first partial pressure end and second divide end on voltage signal.
Optionally, Switching Power Supply is used to be converted to the DC input voitage of direct-flow input end the electricity of predetermined voltage classPressure, and realize voltage stabilizing function.
Optionally, the first partial pressure unit includes: first resistor R1, second resistance R2, wherein one end of first resistor R1 connectsDirect-flow input end is connect, the other end of first resistor R1 is first point of press bond；One end of second resistance R2 and the first partial pressure endConnection, the other end of second resistance R2 are connect with common end.
Optionally, circuit further include: one end of 3rd resistor R3,3rd resistor R3 and the control terminal of controllable switch unit connectIt connects, the other end of 3rd resistor R3 and first point of press bond.
Optionally, the first partial pressure unit further include: first capacitor C1, one end of first capacitor C1 connect with the first partial pressure endIt connects, the other end of first capacitor C1 is connect with common end.
Optionally, the first partial pressure unit further include: zener diode D1, the cathode of zener diode D1 and the first partial pressure endThe anode of connection, zener diode D1 is connect with common end.
Optionally, isolated location includes: diode D2, and the cathode of diode D2 and the control terminal of controllable switch unit connectIt connects, anode and the second point of press bond of diode D2.
Optionally, circuit further include: the 4th resistance R4 and the second capacitor C2, wherein one end of the 4th resistance R4 and controllableThe first switch end of switch unit connects, and the other end of the 4th resistance R4 is connect with a pole plate of the second capacitor C2, the second electricityThe second switch end of another pole plate and controllable switch unit for holding C2 connects.
Optionally, controllable switch unit is insulating gate type field effect tube Q1, wherein the control terminal of controllable switch unit is exhaustedThe grid of edge grid-type field-effect tube Q1, the first switch end of controllable switch unit are the source electrode of insulating gate type field effect tube Q1, canThe second switch end for controlling switch unit is the drain electrode of insulating gate type field effect tube Q1.
Optionally, the second partial pressure unit includes: the 5th resistance R5, triode Q2, the 6th resistance R6, wherein the 5th resistanceOne end of R5 is connect with the emitter of triode Q2, and the other end of the 5th resistance R5 is connect with common end；The one of 6th resistance R6End is connect with the output end of Switching Power Supply, and the other end of the 6th resistance R6 is connect with the base stage of triode Q2；The collection of triode Q2Electrode and the output end of Switching Power Supply connect；The transmitting of triode Q2 extremely second divides end.
Optionally, the second partial pressure unit includes: the 5th resistance R5, triode Q2, control chip, wherein the 5th resistance R5One end connect with the emitter of triode Q2, the other end of the 5th resistance R5 is connect with common end；Chip is controlled by switch electricitySource power supply, the control terminal for controlling chip are connect with the base stage of triode Q2；The collector of triode Q2 and the output of Switching Power SupplyEnd connection；The transmitting of triode Q2 extremely second divides end.
Optionally, the second partial pressure unit a further include: pole plate of third capacitor C3, third capacitor C3 and common end connectIt connects, another pole plate of third capacitor is connect with the emitter of triode Q2.
The anti-reverse connection circuit of direct current power supply with self-test interlocking anti-interference function provided through the embodiment of the present invention, passes throughThe circuit, in DC power supply reversal connection, because DC output end is equal with the potential of common end, the first partial pressure unit and the second partial pressureUnit both ends do not have potential difference, and the first partial pressure end and second divide on end all without voltage signal, and controllable switch unit can not be ledLogical, the positive input signal loaded on DC output end can not access in circuit loop, and the load accessed in circuit can not workMake；When DC power supply just connects, if the voltage signal at the first partial pressure end divided from direct-flow input end, and it is electric from switchThe voltage signal at the second partial pressure end that the output end in source divides, any of the two voltage signals, which can reach, controllably to be openedThe cut-in voltage for closing unit can be realized as the conducting of controllable switch unit.Solves the DC power supply based on controllable switch unitReverse-connection preventing circuit low problem of reliability due to voltage fluctuation, improves the reliability of anti-reverse connection circuit of direct current power supply.
Specific embodiment
The feature and exemplary embodiment of various aspects of the invention is described more fully below, in order to make mesh of the invention, technical solution and advantage be more clearly understood, with reference to the accompanying drawings and embodiments, the present invention is further retouched in detailIt states.It should be understood that described herein, the specific embodiments are only for explaining the present invention, is not intended to limit the present invention.For abilityFor field technique personnel, the present invention can be implemented in the case where not needing some details in these details.It is right belowThe description of embodiment is used for the purpose of better understanding the present invention to provide by showing example of the invention.
It should be noted that, in this document, relational terms such as first and second and the like are used merely to a realityBody or operation are distinguished with another entity or operation, are deposited without necessarily requiring or implying between these entities or operationIn any actual relationship or order or sequence.Moreover, the terms "include", "comprise" or its any other variant are intended toNon-exclusive inclusion, so that the process, method, article or equipment including a series of elements is not only wanted including thoseElement, but also including other elements that are not explicitly listed, or further include for this process, method, article or equipmentIntrinsic element.In the absence of more restrictions, the element limited by sentence " including ... ", it is not excluded that includingThere is also other identical elements in the process, method, article or equipment of the element.
A kind of anti-reverse connection circuit of direct current power supply with self-test interlocking anti-interference function, Fig. 3 are provided in the present embodimentIt is the topology diagram of the anti-reverse connection circuit of direct current power supply according to an embodiment of the present invention with self-test interlocking anti-interference function, such asShown in Fig. 3, which includes: direct-flow input end 10, DC output end 20, controllable switch unit 30,One partial pressure unit 40, isolated location 50, Switching Power Supply 60 and the second partial pressure unit 70, wherein the first partial pressure unit 40 is connected toBetween direct-flow input end 10 and common end, and draw the first partial pressure end；The input terminal and direct-flow input end 10 of Switching Power Supply 60 connectIt connects；Second partial pressure unit 70 is connected between the output end and common end of Switching Power Supply 60, and draws the second partial pressure end；Controllably openThe control terminal and first point of press bond of unit 30 are closed, the first switch end of controllable switch unit 30 and DC output end 20 connectIt connects, the second switch end of controllable switch unit 30 is connect with common end；One end of isolated location 50 and controllable switch unit 30Control terminal connection, the other end of isolated location 50 and second point of press bond, isolated location 50 for be isolated the first partial pressure end withVoltage signal on second partial pressure end.
By foregoing circuit, in DC power supply reversal connection, because DC output end is equal with the potential of common end, the first partial pressureUnit and the second partial pressure unit both ends do not have potential difference, and the first partial pressure end and second divide on end all without voltage signal, controllablySwitch unit can not be connected, and the positive input signal loaded on DC output end can not access in circuit loop, connect in circuitThe load entered can not work；When DC power supply just connects, as long as the voltage at the first partial pressure end divided from direct-flow input endSignal, and the voltage signal at the second partial pressure end that output end from Switching Power Supply divides, it is any in the two voltage signalsA cut-in voltage that can reach controllable switch unit can be realized as the conducting of controllable switch unit.It solves and is based on controllably openingThe anti-reverse connection circuit of direct current power supply of pass unit low problem of reliability due to voltage fluctuation, improves anti-reverse connection circuit of direct current power supplyReliability.
It should be noted that according to circuit topological structure figure provided in this embodiment, in conjunction with anti-reverse connection circuit of direct current power supplyConcrete application scene, with general circuit design theoretical knowledge, so that it may determine the tool of each component in the present embodimentBody type selecting and parameter, therefore the specific type selecting and parameter of each component are no longer enumerated in the present embodiment.
Optionally, Switching Power Supply 60 is used to the DC input voitage of direct-flow input end 10 being converted to predetermined voltage classVoltage, and realize voltage stabilizing function.Switching Power Supply 60 with voltage stabilizing function can guarantee the steady of voltage signal on the second partial pressure endIt is fixed, further increase the reliability of the anti-reverse connection circuit of direct current power supply of the present embodiment.
Fig. 4 is the excellent of the anti-reverse connection circuit of direct current power supply according to an embodiment of the present invention with self-test interlocking anti-interference functionSelect topology diagram.It is described and illustrates below in conjunction with anti-reverse connection circuit of direct current power supply of the Fig. 4 to the present embodiment.
Optionally, partial pressure unit is by the way of multiple electric resistance partial pressures, such as the first partial pressure unit 40 includes: first resistorR1, second resistance R2, wherein one end of first resistor R1 connects direct-flow input end 10, and the other end of first resistor R1 is firstDivide press bond；One end of second resistance R2 and first point of press bond, the other end of second resistance R2 are connect with common end.
Optionally, circuit further include: one end of 3rd resistor R3,3rd resistor R3 and the control terminal of controllable switch unit 30Connection, the other end of 3rd resistor R3 and first point of press bond.3rd resistor R3 is controllable for limiting the first partial pressure end flow directionThe electric current of the control terminal of switch unit.
Optionally, the first partial pressure unit 40 further include: first capacitor C1, one end of first capacitor C1 connect with the first partial pressure endIt connects, the other end of first capacitor C1 is connect with common end.First capacitor C1 is for filtering.
Optionally, the first partial pressure unit 40 further include: zener diode D1, the cathode of zener diode D1 and the first partial pressureThe anode of end connection, zener diode D1 is connect with common end.Zener diode D1 is for stablizing the both ends second resistance R2Voltage, the voltage at the both ends second resistance R2 are the voltage at the first partial pressure end.
Optionally, isolated location 50 includes: diode D2, the cathode of diode D2 and the control terminal of controllable switch unit 30Connection, anode and the second point of press bond of diode D2.
Optionally, circuit further include: the 4th resistance R4 and the second capacitor C2, wherein one end of the 4th resistance R4 and controllableThe first switch end of switch unit 30 connects, and the other end of the 4th resistance R4 is connect with a pole plate of the second capacitor C2, and secondAnother pole plate of capacitor C2 is connect with the second switch end of controllable switch unit 30.4th resistance R4 and the second capacitor C2 is constitutedSoft starting circuit；Second capacitor C2 also acts as the effect of filtering.
Controllable switch unit 30 includes but is not limited to: triode, insulating gate type field effect tube, relay etc..In this implementationIn example, in order to reduce loss of the controllable switch unit 30 to power supply, optionally, controllable switch unit 30 is insulated-gate type field effectPipe Q1, wherein the control terminal of controllable switch unit 30 is the grid of insulating gate type field effect tube Q1, the of controllable switch unit 30One switch terminals are the source electrode of insulating gate type field effect tube Q1, and the second switch end of controllable switch unit 30 is insulated-gate type field effectThe drain electrode of pipe Q1.
With reference to Fig. 5, the second partial pressure unit can also be by the way of multiple electric resistance partial pressures.Due to the output electricity of Switching Power SupplyIt presses more stable, therefore using one there is the triode of fixed conduction voltage drop can ensure the second partial pressure to substitute divider resistanceThe voltage class of the voltage signal at end keeps stablizing.For this purpose, in the present embodiment, the second partial pressure unit 70 includes: the 5th resistanceR5, triode Q2, the 6th resistance R6, wherein one end of the 5th resistance R5 is connect with the emitter of triode Q2, the 5th resistance R5The other end connect with common end；One end of 6th resistance R6 is connect with the output end of Switching Power Supply 60, and the 6th resistance R6's is anotherOne end is connect with the base stage of triode Q2；The collector of triode Q2 is connect with the output end of Switching Power Supply 60；Triode Q2'sThe extremely second partial pressure of transmitting end.
With reference to Fig. 4, the base voltage signal of triode Q2 can also directly be generated by control chip, and the control chip is preferredThe MCU of equipment where reverse-connection preventing circuit.Optionally, the second partial pressure unit 70 includes: the 5th resistance R5, triode Q2, controlChip MCU, wherein one end of the 5th resistance R5 is connect with the emitter of triode Q2, the other end of the 5th resistance R5 with it is publicEnd connection；Control chip MCU is powered by Switching Power Supply 60, and the control terminal of control chip MCU is connect with the base stage of triode Q2；ThreeThe collector of pole pipe Q2 is connect with the output end of Switching Power Supply 60；The transmitting of triode Q2 extremely second divides end.
Optionally, the second partial pressure unit 70 a further include: pole plate of third capacitor C3, third capacitor C3 and common end connectIt connects, another pole plate of third capacitor is connect with the emitter of triode Q2.Third capacitor C3 is for filtering.
Fig. 6 is the work of the anti-reverse connection circuit of direct current power supply according to an embodiment of the present invention with self-test interlocking anti-interference functionMake flow chart, is illustrated below in conjunction with the course of work of the Fig. 4 and Fig. 6 to the present embodiment.
In anti-reverse connection circuit of direct current power supply shown in Fig. 4:
If not increasing the interlocking signal generated by MCU, there is larger fluctuation in input supply voltage, but does not influence VCC electricityIn the case that pressure is stablized, Q1 conducting situation will receive the influence of input supply voltage fluctuation.In input voltage fluctuation to lower limit value,So that R1 resistance and R2 resistance is passed through electric resistance partial pressure, metal-oxide-semiconductor Q1 grid voltage is obtained on R2 less than cut-in voltage, Q1 will be extremely disconnectedIt opens, circuit power is cut off, and influences to work normally.
If increasing the interlocking signal generated by MCU, there is larger fluctuation in input supply voltage, but do not influence VCC voltageIn the case where stabilization, Q1 conducting situation not will receive the influence of input supply voltage fluctuation.In input voltage fluctuation to lower limit value,Even if obtaining metal-oxide-semiconductor Q1 grid voltage on R2 less than cut-in voltage, but MCU can produce under stabilized power supply VCC condition of power supplySignal is controlled, makes the conducting of Q2, voltage close to VCC will be generated after Q2 conducting on R5 resistance, interlocking signal is high level at this time.Interlocking signal controls the grid voltage of Q1 after D2, and Q1 is made to obtain cut-in voltage again, maintains Q1 conducting.Q1 conducting, circuitPower supply normal power supply does not influence to work normally.
Therefore, Q1 when anti-reverse connection circuit of direct current power supply provided in this embodiment can prevent external power supply from being interfered by surgeIt malfunctions and turns off.
It is resistance device with reference to Fig. 4, R1~R5；C1~C3 is capacitor element；D1 zener diode；D2 is two pole of switchPipe；Q1 is metal-oxide-semiconductor (G: grid, S: source electrode, D: drain electrode)；Q2 is triode；VCC is decompression transformation of the Vout Jing Guo Switching Power SupplyThe stabilized power supply converted with linear voltage stabilization block；MCU is the master chip of controller, can download control program；Load is load；VDC+ is the anode of DC supply input, and GND is the cathode of DC supply input.D1 is zener diode, and C1 is filter capacitor,For stablizing the voltage obtained on divider resistance R2.R3 is driving current-limiting resistance, for limiting by Q1 device G grid control letterNumber size of current.D2 is switching diode, for the voltage signal for the starting that interlocking signal and R2 divider resistance obtain to be isolated.R4 and C2 constitutes RC soft starting circuit, and the noise jamming of Q1 devices switch signal generation can be absorbed.
When wiring is correct, R1 resistance and R2 resistance pass through electric resistance partial pressure, obtain that opening for metal-oxide-semiconductor Q1 can be opened on R2Voltage is opened, so that Q1 is connected, power vd C+ reaches power supply GND forming circuit, normal power supply by Load load.
In the case where input supply voltage has larger fluctuation but does not influence VCC voltage stabilization, Q1 be connected situation not byThe influence of input supply voltage fluctuation, this process are called " circuit anti-interference ", power supply disturbance can be effectively prevent to lead to MOS switchMalfunction.
With reference to Fig. 6, the present embodiment so-called " circuit anti-interference " specifically refers to: MCU is in stabilized power supply VCC condition of power supplyUnder, it can produce control signal, make the conducting of Q2, voltage close to VCC will be generated after Q2 conducting on R5 resistance, C3 is used for R5Electric resistance partial pressure post filtering, interlocking signal is high level at this time.The present embodiment so-called " self-test interlocking " refers to: interlocking signal is (i.e.Voltage signal on second partial pressure end) the G grid voltage of control Q1 after D2, so that Q1 is obtained cut-in voltage again, maintains Q1Conducting；Control instruction is sent by MCU, Q1 is made to maintain conducting.
When wiring error, Q1 device G grid is unable to get cut-in voltage, is in close state always, power vd C+ withoutMethod reaches power supply GND forming circuit through overload Load, and no current in circuit can prevent circuit burnout and controller from bursting.
Anti-reverse connection circuit of direct current power supply provided by the above embodiment can be applied to various set using the electric appliance of DC power supplyIt is standby, such as DC power supply air-conditioning etc..
In conclusion through the above embodiments of the present invention and embodiment, can be realized it is following the utility model has the advantages that
1, it prevents air-conditioner set input power polarity connection from instead resulting in controller and burns and fry plate；
2, the power consumption of itself device of the anti-circnit NOT of power supply is reduced, it is low to improve circuit working efficiency；
3, the switching signal of controllable switch unit realizes interlocking, and switch caused by preventing external power supply from being interfered by surge missesMovement.
The foregoing is only a preferred embodiment of the present invention, is not intended to restrict the invention, for the skill of this fieldFor art personnel, the invention may be variously modified and varied.All within the spirits and principles of the present invention, made any to repairChange, equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.