Dual power supply circuit and electronic equipment

Abstract

The present application relates to the technical field of power supply circuits, and discloses a dual-power supply circuit and electronic equipment, the circuit comprising a first power supply module, a second power supply module, a voltage comparison module and a conduction control module; the two input ends of the voltage comparison module are respectively connected to the first power supply module and the second power supply module, for comparing the received first input voltage and the second input voltage, and outputting corresponding level signals; the conduction control module, one end of which is connected to the voltage comparison module, and the other two ends of which are respectively connected to the first power supply module and the second power supply module; the conduction control module controls the first power supply module to conduct when receiving a level signal of the first state; the conduction control module controls the second power supply module to conduct when receiving a level signal of the second state. Through this circuit, power can be supplied through one of the two power supply circuits, and when one power supply fails, it can automatically switch to the other power supply for power supply.

Description

Technical Field

[0001] The present application relates to the technical field of power supply circuits, and in particular to a dual power supply circuit and electronic equipment. Background Art

[0002] For industrial loads, the reliability and stability of their power supply are relatively high. Therefore, in the prior art, in order to avoid affecting the operation of the load when there is only one power supply and the power supply fails, the industrial downstream loads usually use dual power supplies, and can switch to another power supply when one power supply fails. However, the prior art usually uses two diodes in parallel or a diode and two PMOS tubes in series in parallel to achieve dual power supply. Since the diode has a voltage drop problem, the circuit will have losses on the diode. In addition, when the two voltages are similar, the power supply paths of the two power supplies are often turned on, which leads to unreliable and unstable power supply to the downstream loads. Utility Model Content

[0003] In view of this, an embodiment of the present application provides a dual power supply circuit and an electronic device, which can realize power supply through one of the two power supply circuits, and when one power supply fails, it can automatically switch to the other power supply for power supply.

[0004] In a first aspect, an embodiment of the present application provides a dual power supply circuit, including: a first power supply module, a second power supply module, a voltage comparison module and a conduction control module;

[0005] One input end of the voltage comparison module is connected to the first power supply module, and the other input end is connected to the second power supply module. The voltage comparison module is used to compare the received first input voltage of the first power supply module and the second input voltage of the second power supply module, and output a corresponding level signal according to the comparison result;

[0006] The input end of the conduction control module is connected to the voltage comparison module, one output end is connected to the first power supply module, and the other output end is connected to the second power supply module; the conduction control module is used to control the first power supply module to be turned on and the second power supply module to be turned off when receiving the level signal of the first state; the conduction control module is used to control the second power supply module to be turned on and the second power supply module to be turned off when receiving the level signal of the second state; wherein the turned-on power supply module is used to power the load.

[0007] In some embodiments, a DC voltage regulator module is also included;

[0008] The DC voltage stabilizing module is used to receive the input voltage of the first power supply module or the second power supply module, and output a stable voltage as a reference voltage of the voltage comparison module.

[0009] In some embodiments, the voltage comparison module includes a voltage comparator;

[0010] The non-phase input terminal of the voltage comparator is connected to the positive electrode of the output terminal of the first power supply of the first power supply module;

[0011] The inverting input terminal of the voltage comparator is connected to the positive electrode of the output terminal of the second power supply of the second power supply module;

[0012] The output end of the voltage comparator is connected to the input end of the conduction control module.

[0013] In some embodiments, the conduction control module includes a first conduction control unit and a second conduction control unit;

[0014] The first conduction control unit is used to turn on the first power supply module when receiving the level signal of the first state; wherein the level signal of the first state is the reference voltage;

[0015] The second conduction control unit is used to turn on the second power supply module when receiving the level signal of the second state.

[0016] In some embodiments, the first conduction control unit includes a first transistor; the base of the first transistor is connected to the output end of the voltage comparison module; the collector of the first transistor is connected to the first power supply module;

[0017] The second conduction control unit includes a second triode and a third triode; the base of the second triode is connected to the output end of the voltage comparison module; the collector of the second triode is connected to the base of the third triode; and the collector of the third triode is connected to the second power supply module.

[0018] In some embodiments, the first power supply module includes a first MOS tube; the drain of the first MOS tube is connected to the positive electrode of the output terminal of the first power supply; the gate of the first MOS tube is connected to the collector of the first transistor; the source of the first MOS tube is used to connect to the load;

[0019] The second power supply module includes a second MOS tube; the drain of the second MOS tube is connected to the positive electrode of the output end of the second power supply; the gate of the second MOS tube is connected to the collector of the third transistor; and the source of the second MOS tube is connected to the load.

[0020] In some embodiments, the DC voltage stabilization module includes a fourth transistor and a Zener diode;

[0021] The base of the fourth transistor is connected to the cathode of the Zener diode;

[0022] The output end of the first power supply module and the output end of the second power supply module are connected to the collector of the fourth transistor; and the output end of the first power supply module and the output end of the second power supply module are also connected to the connection line between the fourth transistor and the Zener diode.

[0023] In some embodiments, the conduction control module further includes a first voltage-dividing resistor and a second voltage-dividing resistor;

[0024] The first voltage-dividing resistor and the second voltage-dividing resistor are connected in series;

[0025] One end of the first voltage-dividing resistor is connected to the collector of the first transistor; one end of the second voltage-dividing resistor is connected to the connection line between the source of the first MOS tube and the load;

[0026] The gate of the first MOS tube is connected to a connection line between the first voltage-dividing resistor and the second voltage-dividing resistor.

[0027] In some embodiments, the conduction control module further includes a third voltage-dividing resistor and a fourth voltage-dividing resistor;

[0028] The third voltage-dividing resistor and the fourth voltage-dividing resistor are connected in series;

[0029] One end of the third voltage-dividing resistor is connected to the collector of the third transistor; one end of the fourth voltage-dividing resistor is connected to the connection line between the source of the second MOS tube and the load;

[0030] The gate of the second MOS tube is connected to a connection line between the third voltage-dividing resistor and the fourth voltage-dividing resistor.

[0031] In a second aspect, an embodiment of the present application provides an electronic device, comprising the above-mentioned dual power supply circuit.

[0032] The embodiments of the present application have the following beneficial effects: the present application compares the received first input voltage of the first power supply module and the second input voltage of the second power supply module through a voltage comparison module, and outputs a corresponding level signal according to the comparison result, and then the conduction control module controls the conduction of the first power supply module or the conduction of the second control module according to the state of the received level signal, thereby realizing power supply through one of the two power supply circuits, and when one power supply fails, it can automatically switch to the other power supply for power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 A connection diagram of a dual power supply circuit according to an embodiment of the present application is shown;

[0035] Figure 2 A circuit diagram of a dual power supply circuit according to an embodiment of the present application is shown.

[0036] Description of main component symbols:

[0037] 100 - first power supply module; 200 - second power supply module; 300 - voltage comparison module; 400 - conduction control module; 500 - direct current voltage stabilization module; 600 - load. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0039] The components of the embodiments of the present application generally described and shown in the drawings herein may be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0040] Hereinafter, the terms "including", "having" and their cognates that can be used in various embodiments of the present application are intended only to indicate specific features, numbers, steps, operations, elements, components or a combination of the foregoing items, and should not be understood as first excluding the existence of one or more other features, numbers, steps, operations, elements, components or a combination of the foregoing items or increasing the possibility of one or more features, numbers, steps, operations, elements, components or a combination of the foregoing items. In addition, the terms "first", "second", "third" and the like are only used to distinguish descriptions and cannot be understood as indicating or implying relative importance.

[0041] Unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meanings as those generally understood by those skilled in the art to which the various embodiments of the present application belong. The terms (such as those defined in generally used dictionaries) will be interpreted as having the same meanings as the contextual meanings in the relevant technical field and will not be interpreted as having idealized meanings or overly formal meanings unless clearly defined in the various embodiments of the present application.

[0042] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0043] The prior art usually adopts two diodes in parallel or one diode and two PMOS tubes in series in parallel to realize dual power supply. Since the diode has a voltage drop problem, the circuit will have losses on the diode. In addition, when the two voltages are similar, the power supply paths of the two power supplies are often turned on, which leads to unreliable and unstable power supply to the subsequent load.

[0044] Based on this, the present application proposes a dual-power supply circuit and electronic device to achieve stability and reliability in powering the subsequent load, avoid the impact of reverse power connection on the load, and prevent current backflow from one power supply to another.

[0045] The dual power supply circuit is first described below in conjunction with some specific embodiments.

[0046] Figure 1 A connection diagram of a dual power supply circuit of an embodiment of the present application is shown. Exemplarily, the dual power supply circuit includes: a first power supply module 100 , a second power supply module 200 , a voltage comparison module 300 and a conduction control module 400 .

[0047] In this embodiment, one input end of the voltage comparison module 300 is connected to the first power supply module 100, and the other input end is connected to the second power supply module 200. The voltage comparison module 300 is used to receive a first input voltage input by the first power supply module 100 and a second input voltage input by the second power supply module 200, compare the first input voltage and the second input voltage, and then output a corresponding level signal according to the comparison result.

[0048] The level signal includes a level signal in a first state and a level signal in a second state.

[0049] In this embodiment, the input end of the conduction control module 400 is connected to the voltage comparison module 300, one output end is connected to the first power supply module 100, and the other output end is connected to the second power supply module 200; when the conduction control module 400 receives a level signal of the first state, it controls the first power supply module 100 to be turned on and the second power supply module 200 to be turned off, so as to supply power to the subsequent-stage load 600 through the first power supply module 100; when the conduction control module 400 receives a level signal of the second state, it controls the second power supply module 200 to be turned on and the first power supply module 100 to be turned off, so as to supply power to the subsequent-stage load 600 through the second power supply module 200.

[0050] It can be understood that the description of "first" and "second" in the first state level signal and the second state level signal is only to distinguish the different level signals generated by the voltage comparison module 300 in different situations. In actual use, the user can also set the second state level signal to turn on the first power supply module 100 and turn off the second power supply module 200; and set the first state level signal to turn on the second power supply module 200 and turn off the first power supply module 100, which is not limited here.

[0051] In some embodiments, the dual power supply circuit further includes a DC voltage regulator module 500. The DC voltage regulator module 500 is connected to the first power supply module 100 and the second power supply module 200, and is used to receive an input voltage from the first power supply module 100 or the second power supply module 200, and output a stable voltage to the voltage comparison module 300, and use the stable voltage as a reference voltage for the voltage comparison module 300.

[0052] Figure 2 A circuit diagram of a dual power supply circuit according to an embodiment of the present application is shown.

[0053] like Figure 2As shown, the voltage comparison module 300 includes a voltage comparator U; the positive input terminal of the voltage comparator U is connected to the positive pole of the output terminal of the first power supply DC1 of the first power supply module 100, and is used to receive the voltage of the positive pole of the output terminal of the first power supply DC1; the negative input terminal of the voltage comparator U is connected to the positive pole of the output terminal of the second power supply DC2 of the second power supply module 200, and is used to receive the voltage of the positive pole of the output terminal of the second power supply DC2; the output terminal of the voltage comparator U is connected to the conduction control module 400. The voltage comparator U is used to compare the received voltage of the positive pole of the output terminal of the first power supply DC1 with the voltage of the positive pole of the output terminal of the second power supply DC2. If the voltage of the positive pole of the output terminal of the first power supply DC1 is greater than the voltage of the positive pole of the output terminal of the second power supply DC2, the output terminal of the voltage comparator U outputs a high level; if the voltage of the positive pole of the output terminal of the first power supply DC1 is less than the voltage of the positive pole of the output terminal of the second power supply DC2, the output terminal of the voltage comparator U outputs a low level. Since the reference voltage of the voltage comparator U in this embodiment is the stable voltage of the DC voltage regulator module 500, and the DC voltage regulator module 500 is connected to the positive phase of the comparator, the high level output by the output end of the voltage comparator U is the reference voltage.

[0054] In a specific implementation, a first current limiting resistor R1 is arranged between the positive pole of the output terminal of the first power supply DC1 and the voltage comparator U; a second current limiting resistor R2 is arranged between the positive pole of the output terminal of the second power supply DC2 and the voltage comparator U. The first current limiting resistor R1 and the second current limiting resistor can avoid the problem of damage to the voltage comparator U due to excessive current.

[0055] In a specific implementation, this embodiment also includes a first resistor R3 and a second resistor R4; one end of the first resistor R3 is connected to the connection line between the first current limiting resistor R1 and the positive phase input terminal of the voltage comparator U, and the other end of the first resistor R3 is grounded; one end of the second resistor R4 is connected to the connection line between the second current limiting resistor R2 and the positive phase input terminal of the voltage comparator U, and the other end of the second resistor R4 is grounded; the setting of the first resistor R3 and the second resistor R4 can make the voltage comparator U input determined at a fixed value, thereby avoiding false triggering of the comparator in a high impedance state.

[0056] In a specific implementation, this embodiment further includes a positive feedback resistor R5, one end of which is connected to the output end of the voltage comparator U, and the other end is connected to the connection line between the first current limiting resistor R1 and the positive phase input end of the voltage comparator U.

[0057] In a specific implementation, this embodiment also includes a first pull-up resistor R6; one end of the first pull-up resistor R6 is connected to the connection line between the voltage comparator U and the conduction control module 400, and the other end is connected to the reference voltage, so that the output of the voltage comparator U can be made high by default, thereby avoiding false triggering of the comparator in the high-impedance state.

[0058] In this embodiment, the conduction control module 400 includes a first conduction control unit and a second conduction control unit; one end of the first conduction control unit is connected to the output end of the voltage comparator U, and the other end is connected to the first power supply module 100, and is used to turn on the first power supply module 100 when receiving a level signal of a first state output by the voltage comparator U; wherein the first level signal is a reference voltage; one end of the second conduction control unit is connected to the output end of the voltage comparator U, and the other end is connected to the second power supply module 200, and is used to turn on the second power supply module 200 when receiving a level signal of a second state.

[0059] Specifically, the first conduction control unit includes a first transistor Q1; the base of the first transistor Q1 is connected to the output end of the voltage comparison module 300; and the collector of the first transistor Q1 is connected to the first power supply module 100. The second conduction control unit includes a second transistor Q2 and a third transistor Q3; the base of the second transistor Q2 is connected to the output end of the voltage comparison module 300; the collector of the second transistor Q2 is connected to the base of the third transistor Q3; and the collector of the third transistor Q3 is connected to the second power supply module 200.

[0060] In one embodiment, the first power supply module 100 includes a first MOS transistor Q4; the drain of the first MOS transistor Q4 is connected to the positive electrode of the output terminal of the first power supply DC1; the gate of the first MOS transistor Q4 is connected to the collector of the first transistor Q1; the source of the first MOS transistor Q4 is connected to the DC voltage regulator module 500 and the load 600. The second power supply module 200 includes a second MOS transistor Q5; the drain of the second MOS transistor Q5 is connected to the positive electrode of the output terminal of the second power supply DC2; the gate of the second MOS transistor Q5 is connected to the collector of the third transistor Q3; the source of the second MOS transistor Q5 is connected to the DC voltage regulator module 500 and the load 600.

[0061] It can be understood that when the voltage of the first power supply is greater than the voltage of the second power supply DC2, the voltage received by the positive input terminal of the voltage comparator U is greater than the voltage received by the inverting input terminal, and the voltage difference between the positive input terminal voltage and the inverting input terminal voltage of the voltage comparator U is positive, and the voltage comparator U outputs a high level. At this time, the base voltage of the first transistor Q1 is a high level, and the first transistor Q1 is turned on. Since the gate of the first MOS transistor Q4 is connected to the collector of the first transistor Q1, the gate voltage of the first MOS transistor Q4 is switched from a high level to a low level, thereby making the gate voltage of the first transistor Q1 less than the source voltage, and the first MOS transistor Q4 is turned on. At this time, the load 600 is powered by the first power supply DC1. At the same time, since the base of the second triode Q2 is connected to the output end of the voltage comparator U, the base voltage of the second triode Q2 is at a high level, the second triode Q2 is turned on, the collector voltage of the second triode Q2 is at a low level, and since the collector of the second triode Q2 is connected to the base of the third triode Q3, the base voltage of the third triode Q3 is at a low level, and the third triode Q3 is turned off. At this time, the gate voltage and the source voltage of the second MOS tube Q5 are equal, and the second MOS tube Q5 is in a cut-off state, so the second power supply DC2 cannot supply power to the subsequent load 600.

[0062] When the voltage of the first power supply is less than the voltage of the second power supply DC2, the voltage received by the positive input terminal of the voltage comparator U is less than the voltage received by the inverting input terminal, and the voltage difference between the positive input terminal voltage and the inverting input terminal voltage of the voltage comparator U is negative, and the voltage comparator U outputs a low level. At this time, the base voltage of the first transistor Q1 is a low level, the first transistor Q1 is turned off, the gate voltage of the first MOS tube Q4 is equal to the drain voltage, and the first MOS tube Q4 is turned off, so the first power supply DC1 cannot supply power to the subsequent load 600. At the same time, since the base of the second transistor Q2 is connected to the output end of the voltage comparator U, the base voltage of the second transistor Q2 is low, the second transistor Q2 is cut off, the base of the third transistor Q3 is high, the third transistor Q3 is turned on, and the collector of the third transistor Q3 is low, so that the gate voltage of the second MOS transistor Q5 is less than the source voltage, the second MOS transistor Q5 is turned on, and the load 600 is powered by the second power supply DC2. Through the above-mentioned first power supply module 100, second power supply module 200, voltage comparison module 300 and conduction control module 400, it can be realized that when both power supply modules are normal, the load 600 is powered by a power supply that provides a higher voltage.

[0063] Combination Figure 2 The circuit structure shown below gives an example of how to implement power supply circuit switching when a power supply fails.

[0064] Specifically, when the post-stage load 600 is powered by the first power supply DC1, the voltage received by the positive input terminal of the voltage comparator U is greater than the voltage received by the inverting input terminal of the voltage comparator U. If the first power supply DC1 fails and loses power, the voltage received by the positive input terminal of the voltage comparator U becomes less than the voltage received by the inverting input terminal of the voltage comparator U. Then, the voltage difference between the positive and inverting inputs of the voltage comparator U switches from a positive value to a negative value, thereby switching the high level of the voltage comparison output to a low level, and the base voltage of the first transistor Q1 switches from a high level to a low level. Then, the first transistor Q1 switches from an on state to an off state, the first transistor Q1 is turned off, the gate voltage of the first MOS tube Q4 is equal to the source voltage, and then the first MOS tube Q4 switches from an on state to an off state, and the power supply path of the first power supply DC1 is cut off. At this time, since the high level of the voltage comparison output is switched to a low level, the base voltage of the second transistor Q2 is a low level, the second transistor is cut off, and the base voltage of the third transistor Q3 is switched from a low level to a high level, so the third transistor Q3 is switched from a cut-off state to a conducting state. At this time, the gate voltage of the second MOS transistor Q5 is less than the source voltage, and the second MOS transistor Q5 is turned on, and the subsequent load 600 can be powered by the second power supply DC2.

[0065] Similarly, when the subsequent load 600 is powered by the second power supply DC2, the voltage received by the positive input terminal of the voltage comparator U is less than the voltage received by the negative input terminal of the voltage comparator U. If the second power supply DC2 fails and loses power, the voltage received by the positive input terminal of the voltage comparator U becomes greater than the voltage received by the negative input terminal of the voltage comparator U, and the voltage difference between the positive and negative inputs of the voltage comparator U switches from a negative value to a positive value, thereby switching the low level of the voltage comparison output to a high level, and the base voltage of the first transistor Q1 switches from a low level to a high level, and the first transistor Q1 switches from a cut-off state to a conducting state, the first transistor Q1 is turned on, the gate voltage of the first MOS tube Q4 is less than the source voltage, and then the first MOS tube Q4 switches from a cut-off state to a conducting state, and the power supply path of the first power supply DC1 is turned on. At this time, the load 600 is powered by the first power supply DC1. At this time, since the low level of the voltage comparison output is switched to a high level, the base voltage of the second transistor Q2 is a high level, the second transistor is turned on, the base voltage of the third transistor Q3 is switched from a high level to a low level, and the third transistor Q3 is switched from a conducting state to a cut-off state. At this time, the gate voltage of the second MOS transistor Q5 is equal to the source voltage, the second MOS transistor Q5 is cut off, and the power supply path of the second power supply DC2 is cut off. The dual power supply circuit in this embodiment can also prevent the power supply from being reversed. Specifically, when the power supply is reversed, the first MOS transistor Q4 or the second MOS transistor Q5 connected in series to the positive pole of the power supply output terminal is in a cut-off state. At this time, the current has no loop in the circuit, so the power supply cannot supply power to the load 600. The situation where the load 600 is damaged when the power supply is reversed is avoided, and the function of preventing reverse connection is realized.

[0066] The dual power supply circuit in this embodiment can also prevent the current from flowing back from one power supply to the other power supply. Specifically, when the load 600 is powered by the first power supply DC1, since the second MOS tube on the positive electrode of the output end of the second power supply DC2 is in the off state, the current from the first power supply module 100 to the second power supply module 200 is prevented from flowing back. Similarly, when the load 600 is powered by the second power supply DC2, since the first MOS tube on the positive electrode of the output end of the first power supply DC1 is in the off state, the current from the second power supply module 200 to the first power supply module 100 is prevented from flowing back. At the same time, due to the low conduction voltage drop and low loss characteristics of MOS, the problem of high loss when the power supply adopts a diode to realize the anti-reverse connection function is solved.

[0067] In this embodiment, the first MOS transistor Q4 and the second MOS transistor Q5 are both PMOS transistors.

[0068] In some embodiments, the dual power supply circuit further includes a fifth current limiting resistor R11, a sixth current limiting resistor R12, and a seventh current limiting resistor R13. The fifth current limiting resistor R11 is connected between the voltage comparator U and the second triode Q2; the sixth current limiting resistor R12 is connected between the voltage comparator U and the first diode D2; the seventh current limiting resistor R13 is connected between the second triode Q2 and the third triode Q3, and is used to prevent excessive current from damaging the first triode Q1, the second triode Q2, or the third triode Q3.

[0069] In some embodiments, the DC voltage stabilizing module 500 includes a fourth transistor Q6 and a Zener diode D1; the base of the fourth transistor Q6 is connected to the negative electrode of the Zener diode; the output end of the first power supply module 100 and the output end of the second power supply module 200 are connected to the collector of the fourth transistor Q6; and the output end of the first power supply module 100 and the output end of the second power supply module 200 are connected to the connecting line between the fourth transistor Q6 and the Zener diode D1.

[0070] It can be understood that the function of the DC voltage stabilizing module 500 is to stabilize the input voltage of the first power supply DC1 and the second power supply with energy source, and output a stable DCIN voltage value, using DCIN as the reference voltage of the voltage comparator U. When the power is input, the current flows to the DC voltage stabilizing module 500 through the first MOS tube Q4 connected in series to the positive electrode of the power supply or the body diode on the MOS tube. When the base voltage of the fourth transistor Q6 is less than the Zener voltage Ud of the Zener diode D1, the Zener diode D1 is turned off, the fourth transistor Q6 is turned on, and the DC voltage stabilizing module 500 outputs DCIN to boost the voltage; when the base voltage of the fourth transistor Q6 is greater than the Zener voltage Ud of the Zener diode D1, the Zener diode D1 is turned on, the fourth transistor Q6 is turned off, and the DC voltage stabilizing module 500 outputs DCIN to reduce the voltage. When the on-off of the first MOS tube Q4 or the second MOS tube Q5 is balanced, the voltage stabilizing circuit stably outputs the DCIN voltage value Ud.

[0071] In some embodiments, the dual power supply circuit also includes an eighth current limiting resistor R14 and a ninth current limiting resistor R15; one end of the eighth current limiting resistor R14 is connected to the output terminal of the first power supply module 100 and the output terminal junction of the second power supply module 200, and the other end is connected to the collector of the fourth transistor Q6; one end of the ninth current limiting resistor R15 is connected to the output terminal of the first power supply module 100 and the output terminal junction of the second power supply module 200, and the other end is connected to the connecting line between the fourth transistor Q6 and the Zener diode D1.

[0072] In some embodiments, the dual power supply circuit further includes a first voltage-dividing resistor R7, a second voltage-dividing resistor R8, a third voltage-dividing resistor R9, and a fourth voltage-dividing resistor R10; the first voltage-dividing resistor R7 and the second voltage-dividing resistor R8 are connected in series; one end of the first voltage-dividing resistor R7 is connected to the collector of the second diode Q2; one end of the second voltage-dividing resistor R8 is connected to the connection line between the first MOS tube Q4 and the load 600; the gate of the first MOS tube Q4 is connected to the connection line between the first voltage-dividing resistor R7 and the second voltage-dividing resistor R8. The third voltage-dividing resistor R9 and the fourth voltage-dividing resistor R10 are connected in series; one end of the third voltage-dividing resistor R9 is connected to the collector of the third triode Q3; one end of the fourth voltage-dividing resistor R10 is connected to the connection line between the second MOS tube Q5 and the load 600; the gate of the second MOS tube Q5 is connected to the connection line between the third voltage-dividing resistor R9 and the fourth voltage-dividing resistor R10.

[0073] In some embodiments, the dual power supply circuit further includes a first diode D2 and a second diode D3, wherein the anode of the first diode D2 is connected to the emitter of the first transistor Q1, and the cathode of the first diode D2 is grounded; the anode of the second diode D3 is connected to the emitter of the third transistor Q3, and the cathode of the second diode D3 is grounded, thereby preventing the first power supply DC1 and the second power supply DC2 from backflowing.

[0074] In some embodiments, the dual power supply circuit further includes a first filter capacitor C1, a second filter capacitor C2, and a third filter capacitor C3. Among them, one end of the first filter capacitor C1 is connected to the DCID terminal and the other end is grounded, one end of the second filter capacitor C2 is connected to the transmitter of the fourth transistor Q6 and the other end is grounded, and one end of the third filter capacitor C3 is connected to the VDC interface and the other end is grounded, which is used to filter the output signal of the power supply.

[0075] The present application uses a voltage comparator U, a first conduction control unit and a second conduction control unit to realize dual power supply, and controls the subsequent load 600 to use a power supply with a higher voltage as the main power supply for the subsequent load 600, and when one power supply fails, it can automatically switch to the other power supply for power supply, thereby ensuring the stability and reliability of the power supply to the subsequent load 600.

[0076] The present application also provides an electronic device including the above-mentioned dual power supply circuit, wherein the electronic device may include a power supply for powering a subsequent load 600; the electronic device may also be a router, a switch, a gateway, etc.

[0077] The above are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be covered by the protection scope of the present application.

Claims

1. A dual power supply circuit, characterized in that: include: A first power supply module, a second power supply module, a voltage comparison module and a conduction control module; One input end of the voltage comparison module is connected to the first power supply module, and the other input end is connected to the second power supply module. The voltage comparison module is used to compare the received first input voltage of the first power supply module and the second input voltage of the second power supply module, and output a corresponding level signal according to the comparison result; The conduction control module has an input end connected to the voltage comparison module, an output end connected to the first power supply module, and another output end connected to the second power supply module; The conduction control module is used to control the first power supply module to be turned on and the second power supply module to be turned off when receiving the level signal of the first state; the conduction control module is used to control the second power supply module to be turned on and the second power supply module to be turned off when receiving the level signal of the second state; wherein the turned-on power supply module is used to power the load.

2. The dual power supply circuit according to claim 1, characterized in that: It also includes a DC voltage regulator module; The DC voltage stabilizing module is used to receive the input voltage of the first power supply module or the second power supply module, and output a stable voltage as a reference voltage of the voltage comparison module.

3. The dual power supply circuit according to claim 1, characterized in that: The voltage comparison module includes a voltage comparator; The non-phase input terminal of the voltage comparator is connected to the positive electrode of the output terminal of the first power supply of the first power supply module; The inverting input terminal of the voltage comparator is connected to the positive electrode of the output terminal of the second power supply of the second power supply module; The output end of the voltage comparator is connected to the input end of the conduction control module.

4. The dual power supply circuit according to claim 2, characterized in that: The conduction control module includes a first conduction control unit and a second conduction control unit; The first conduction control unit is used to turn on the first power supply module when receiving the level signal of the first state; wherein the level signal of the first state is the reference voltage; The second conduction control unit is used to turn on the second power supply module when receiving the level signal of the second state.

5. The dual power supply circuit according to claim 4, characterized in that: The first conduction control unit includes a first transistor; the base of the first transistor is connected to the output end of the voltage comparison module; the collector of the first transistor is connected to the first power supply module; The second conduction control unit includes a second triode and a third triode; the base of the second triode is connected to the output end of the voltage comparison module; the collector of the second triode is connected to the base of the third triode; and the collector of the third triode is connected to the second power supply module.

6. The dual power supply circuit according to claim 5, characterized in that: The first power supply module includes a first MOS tube; the drain of the first MOS tube is connected to the positive electrode of the output terminal of the first power supply; the gate of the first MOS tube is connected to the collector of the first transistor; the source of the first MOS tube is used to connect to the load; The second power supply module includes a second MOS tube; the drain of the second MOS tube is connected to the positive electrode of the output end of the second power supply; the gate of the second MOS tube is connected to the collector of the third transistor; and the source of the second MOS tube is connected to the load.

7. The dual power supply circuit according to claim 2, characterized in that: The DC voltage stabilization module includes a fourth triode and a Zener diode; The base of the fourth transistor is connected to the cathode of the Zener diode; The output end of the first power supply module and the output end of the second power supply module are connected to the collector of the fourth transistor; and the output end of the first power supply module and the output end of the second power supply module are also connected to the connection line between the fourth transistor and the Zener diode.

8. The dual power supply circuit according to claim 6, characterized in that: The conduction control module further includes a first voltage-dividing resistor and a second voltage-dividing resistor; The first voltage-dividing resistor and the second voltage-dividing resistor are connected in series; One end of the first voltage-dividing resistor is connected to the collector of the first transistor; one end of the second voltage-dividing resistor is connected to the connection line between the source of the first MOS tube and the load; The gate of the first MOS tube is connected to a connection line between the first voltage-dividing resistor and the second voltage-dividing resistor.

9. The dual power supply circuit according to claim 6, characterized in that: The conduction control module further includes a third voltage-dividing resistor and a fourth voltage-dividing resistor; The third voltage-dividing resistor and the fourth voltage-dividing resistor are connected in series; One end of the third voltage-dividing resistor is connected to the collector of the third transistor; one end of the fourth voltage-dividing resistor is connected to the connection line between the source of the second MOS tube and the load; The gate of the second MOS tube is connected to a connection line between the third voltage-dividing resistor and the fourth voltage-dividing resistor.

10. An electronic device, characterized in that: It comprises a dual power supply circuit as described in any one of claims 1 to 9.

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