Protection circuit and electronic equipment

Abstract

The invention provides a protection circuit and electronic equipment, the circuit comprises a first charging control unit, a second charging control unit and an energy storage unit, the first charging control unit is configured to respond to a first control signal and gate a path between a first voltage source and the second charging control unit; the second charging control unit is coupled with the energy storage unit and is provided with a charging branch and a power supply branch, and when the second control signal is in the first state, the charging branch is gated, and the power supply branch is disconnected; when the second control signal is in a second state, the power supply branch is gated, and the charging branch is disconnected; the energy storage unit is configured to execute energy storage operation based on the first voltage source when the charging branch is gated; and when the power supply branch is gated, performing power supply operation. By adopting the technical scheme, the suppression effect of the surge current can be improved, and the service life of the electronic equipment is further prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of circuits, and particularly to a protection circuit and an electronic device. Background Art

[0002] In recent years, with the rapid development of product technologies, there are more and more power supply scenarios such as consumer, medical, and lighting power supplies. The power supply circuits are used in different directions and different products, and these technologies provide higher efficiency. On this basis, it is increasingly necessary to improve the stability of the circuit.

[0003] In some application scenarios, when the circuit is in the initial power-on state, a large inrush current will be generated, reducing the service life of the circuit. Summary of the Invention

[0004] In view of this, the present invention provides a protection circuit and an electronic device to improve the suppression effect of inrush current and thus increase the service life of the electronic device.

[0005] The present invention provides a protection circuit, including: a first charging control unit, a second charging control unit, and an energy storage unit, wherein:

[0006] The first charging control unit is respectively coupled to the second charging control unit and a first voltage source, and is configured to select a path between the first voltage source and the second charging control unit in response to a first control signal;

[0007] The second charging control unit is coupled to the energy storage unit and has a charging branch and a power supply branch. Wherein, when the second control signal is in a first state, the charging branch is selected and the power supply branch is disconnected; and when the second control signal is in a second state, the power supply branch is selected and the charging branch is disconnected;

[0008] The energy storage unit is configured to perform an energy storage operation based on the first voltage source to generate a second voltage source when the charging branch is selected; and perform a power supply operation through the second voltage source when the power supply branch is selected.

[0009] Optionally, the first charging control unit includes: a first biasing module and a first gating module, wherein:

[0010] The first biasing module is coupled to the first voltage source and the first gating module, and is configured to provide a first bias voltage to the first gating module based on the first voltage source when the first control signal is in a second state;

[0011] The first gating module is configured to be in a gated state in response to the first bias voltage and the first voltage source.

[0012] Optionally, the first charging control unit satisfies at least one or more of the following:

[0013] The first biasing module includes: a first biasing resistor, a second biasing resistor, and a first gating transistor. Wherein, a first end of the first biasing resistor is coupled to the first voltage source, and a second end of the first biasing resistor is respectively coupled to a first end of the second biasing resistor and a control end of the first gating module; a second end of the second biasing resistor is coupled to a first end of the first gating transistor; a control end of the first gating transistor is adapted to receive the first control signal, and a second end of the first gating transistor is grounded;

[0014] The first gating module includes: a second gating transistor. A control end of the second gating transistor is coupled to the first biasing module, a first end of the second gating transistor is coupled to the first voltage source, and a second end of the second gating transistor is coupled to the second charging control unit.

[0015] Optionally, at an initial moment, the first control signal and the second control signal have the first state, and after a preset moment when the first control signal has the second state, both the first control signal and the second control signal have the second state;

[0016] Wherein: the preset moment is determined based on the first voltage source and the energy storage unit.

[0017] Optionally, an equivalent resistance of the charging branch is greater than an equivalent resistance of the power supply branch, and when the power supply branch is gated, the charging branch is in a short - circuit state to disconnect the charging branch.

[0018] Optionally, the second charging control unit satisfies at least one or more of the following:

[0019] The power supply branch includes: a second biasing module and a second gating module. Wherein: the second biasing module is respectively coupled to the first charging control unit, the second gating module, and the charging branch, and is configured to provide a second biasing voltage to the second gating module based on the first voltage source when the second control signal is in the second state; the second gating module is configured to be in a gated state in response to the second biasing voltage and the first voltage source;

[0020] The charging branch includes a charging resistor. A first end of the charging resistor is respectively coupled to the first charging control unit and the power supply branch, and a second end of the charging resistor is respectively coupled to the power supply branch and the energy storage unit.

[0021] Optionally, the power supply branch satisfies at least one or more of the following:

[0022] The second biasing module includes: a third biasing resistor, a fourth biasing resistor, and a third gating transistor. Wherein, the first end of the third biasing resistor is respectively coupled to the first charging control unit and the charging branch, and the second end of the third biasing resistor is respectively coupled to the first end of the fourth biasing resistor and the control end of the second gating module; the second end of the fourth biasing resistor is coupled to the first end of the third gating transistor; the control end of the third gating transistor is adapted to receive the second control signal, and the second end of the third gating transistor is grounded;

[0023] The second gating module includes: a fourth gating transistor. The control end of the fourth gating transistor is coupled to the second biasing module. The first end of the fourth gating transistor is respectively coupled to the first charging control unit, the charging branch, and the second biasing module. The second end of the fourth gating transistor is respectively coupled to the energy storage unit and the charging branch.

[0024] Optionally, the protection circuit further satisfies at least one or more of the following:

[0025] A first filter capacitor, disposed at the input end of the first charging control unit and coupled to the first voltage source;

[0026] A second filter capacitor, disposed at the output end of the second charging control unit;

[0027] A first current limiting resistor, the first end of the first current limiting resistor is adapted to receive the first control signal, and the second end of the first current limiting resistor is coupled to the first charging control unit;

[0028] A second current limiting resistor, the first end of the second current limiting resistor is adapted to receive the second control signal, and the second end of the second current limiting resistor is coupled to the second charging control unit;

[0029] A voltage conversion unit, coupled to the output end of the second charging control unit, configured to convert the amplitude of the second voltage source to obtain a power supply voltage.

[0030] Optionally, the voltage conversion unit includes: a voltage conversion chip, a feedback module, and a bootstrap capacitor and an energy storage inductor disposed at the output end of the voltage conversion chip;

[0031] Wherein, the input terminal and the enable terminal of the voltage conversion chip are coupled to the output terminal of the second charging control unit. The output terminal of the voltage conversion chip is respectively coupled to the energy storage inductor and the feedback module, and is coupled to the bootstrap terminal of the voltage conversion chip through the bootstrap capacitor. The feedback terminal of the voltage conversion chip is coupled to the feedback node of the feedback module;

[0032] The feedback module includes a first feedback resistor and a second feedback resistor. Wherein, the first end of the first feedback resistor is coupled to the output terminal of the voltage conversion chip. The second end of the first feedback resistor is respectively coupled to the first end of the second feedback resistor and is connected to the feedback terminal of the voltage conversion chip. The second end of the second feedback resistor is grounded.

[0033] Correspondingly, the present invention further provides an electronic device, including: the protection circuit described in any one of the foregoing items.

[0034] Compared with the prior art, the technical solution of the embodiment of the invention has the following advantages:

[0035] The protection circuit provided by the embodiment of the invention can switch the state of the protection circuit by flexibly switching the state (such as the level state) of the first control signal and / or the second control signal, so that when the second control signal is in the first state, the energy storage unit is charged by the first voltage source; and when the first control signal and the second control signal are in the second state, the power supply operation is performed. In other words, after the charging is completed, the power supply process is carried out, so that the inrush current in the power-on state can be effectively suppressed, and thus the service life of the electronic device is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0037] Figure 1 FIG. shows a schematic structural diagram of a protection circuit in an embodiment of the present invention;

[0038] Figure 2 FIG. shows a specific structural diagram of a protection circuit in an embodiment of the present invention;

[0039] Figure 3 FIG. shows a schematic structural diagram of a voltage conversion unit in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] As described in the background art, when the circuit is in the initial power-on state, a large inrush current will be generated, reducing the service life of the circuit.

[0041] To solve the above technical problems, the present invention provides a protection circuit. By flexibly switching the states (such as voltage levels) of the first control signal and / or the second control signal, the state of the protection circuit can be switched, such that when the second control signal is in the first state, the energy storage unit performs an energy storage operation through the first voltage source; and when the first control signal and the second control signal are in the second state, a power supply operation is performed. In other words, after charging is completed, a power supply process is carried out, thereby effectively suppressing the inrush current in the power-on state and further improving the service life of the electronic device.

[0042] To enable those skilled in the art to better understand and implement the present disclosure, the following refers to the accompanying drawings, and the specific solutions, principles, advantages, and effects of the present disclosure are described in detail through specific embodiments.

[0043] See Figure 1 and Figure 2 , wherein, Figure 1 is a schematic structural diagram of a protection circuit in an embodiment of the present invention, Figure 2 is a specific structural diagram of a protection circuit in an embodiment of the present invention. As shown in Figure 1 and Figure 2 , the protection circuit 100 may include: a first charging control unit 110, a second charging control unit 120, and an energy storage unit 130, wherein:

[0044] The first charging control unit 110 is respectively coupled to the second charging control unit 120 and the first voltage source U1, and is configured to, in response to the first control signal S1, select and connect the path between the first voltage source U1 and the second charging control unit 120;

[0045] The second charging control unit 120 is coupled to the energy storage unit 130 and has a charging branch 122 and a power supply branch 124. Wherein, when the second control signal S2 is in the first state, the charging branch 122 is selected and connected, and the power supply branch 124 is disconnected; and when the second control signal S2 is in the second state, the power supply branch 124 is selected and connected, and the charging branch 122 is disconnected;

[0046] The energy storage unit 130 is configured to, when the charging branch 122 is selected and connected, perform an energy storage operation based on the first voltage source U1 to generate a second voltage source U2; and when the power supply branch 124 is selected and connected, perform a power supply operation through the second voltage source U2.

[0047] In some embodiments, the amplitude of the second voltage source U2 is the same as that of the first voltage source U1; or it can be considered that when the power supply branch 124 is selected, the subsequent-stage circuit is powered by the first voltage source U1.

[0048] Combined with Figure 1 , briefly describe the working principle of the protection circuit 100 in this solution:

[0049] At the initial moment, both the first control signal S1 and the second control signal S2 are in the first state (for example, corresponding to the low level "0"), and the protection circuit 100 is ineffective.

[0050] When the first control signal S1 has the second state (for example, corresponding to the high level "1"), the first charging control unit 110 is selected, and then the first voltage source U1 can supply power to the second charging control unit 120.

[0051] At the same time, the second control signal S2 is still in the first state, so that the charging branch 122 can be selected, thereby forming a path between the first voltage source U1 - the first charging control unit 110 - the charging branch 122 - the energy storage unit 130. Thus, the energy storage unit 130 can perform energy storage operations, so that a second voltage source U2 is generated on the branch where the energy storage unit 130 is located.

[0052] After a period of time, for example, after the energy storage operation of the energy storage unit 130 is completed, at this time the second control signal S2 is also in the second state. Thus, under the action of the first voltage source U1 and the second control signal S2, the power supply branch 124 is selected, so that a path between the first voltage source U1 - the first charging control unit 110 - the power supply branch 124 - the energy storage unit 130 can be formed, and thus power supply operations can be performed.

[0053] That is: by flexibly switching the states (such as the level states) of the first control signal and / or the second control signal, the power supply process can be carried out after charging is completed, thereby effectively suppressing the inrush current in the power-on state, and further improving the service life of the electronic device. In this embodiment, at the initial moment, the first control signal S1 and the second control signal S2 have the first state. That is: the first charging control unit 110 is in the off state and no energy storage operation is performed.

[0054] At the power-on moment, the first control signal S1 switches to the second state, while the second control signal S2 remains in the first state.

[0055] After a preset moment when the first control signal S1 has the second state, both the first control signal S1 and the second control signal S2 have the second state, thereby forming a charging channel. That is: after charging is completed, the power supply branch 124 is opened.

[0056] In this embodiment, the preset time is determined based on the first voltage source U1 and the energy storage unit 130.

[0057] More specifically, the energy storage unit 130 is generally an energy storage capacitor (for example, Figure 2 the schematically shown first energy storage capacitor C1 and second energy storage capacitor C2), and the first voltage source U1 is a fixed value, so that the time required for the energy storage unit 130 to complete energy storage can be determined. Further, after this time, the second control signal S2 has a second state.

[0058] Thus, by switching the states of the first control signal and the second control signal, the effect of suppressing the surge current is achieved.

[0059] It should be noted that the state switching process of the first control signal and the second control signal can be implemented by a control module (such as a CPU), or can be implemented by other means, and the present invention does not make any restrictions thereon.

[0060] In this embodiment, in combination with Figure 1 , referring to Figure 2 , the first charging control unit 110 may include: a first bias module 112 and a first gating module 114, wherein:

[0061] The first bias module 112 is coupled to the first voltage source U1 and the first gating module 114, and is configured to provide a first bias voltage to the first gating module 114 based on the first voltage source U1 when the first control signal S1 is in a second state;

[0062] The first gating module 114 is configured to be in a gated state in response to the first bias voltage and the first voltage source U1.

[0063] Specifically, the first bias module 112 may obtain a first bias voltage based on the first voltage source U1 (for example, by dividing the voltage of the first voltage source U1 to obtain the first bias voltage). When the first control signal S1 is in the second state, the first voltage source U1 can act, so that the first gating module 114 is gated, and further the first charging control unit 110 is gated, and the energy storage operation can be performed.

[0064] And since the first gating module 114 is gated when the first control signal S1 is in the second state, the charging time can be controlled.

[0065] In this embodiment, the first charging control unit 110 may satisfy at least one or more of the following:

[0066] The first bias module 112 includes: a first bias resistor R11, a second bias resistor R12, and a first gating transistor Q1. Among them, a first end of the first bias resistor R11 is coupled to the first voltage source U1, and a second end of the first bias resistor R11 is respectively coupled to a first end of the second bias resistor R22 and a control end of the first gating module 114; a second end of the second bias resistor R2 is coupled to a first end of the first gating transistor Q1; a control end of the first gating transistor Q1 is adapted to input the first control signal S1, and a second end of the first gating transistor Q1 is grounded.

[0067] In other words, the first bias module 112 may include a voltage dividing branch composed of the first bias resistor R11 and the second bias resistor R12, thereby providing a first bias voltage for the control end of the first gating module 114. In this way, when the first control signal S1 at the control end of the first gating transistor Q1 is in the second state, the first bias voltage can be provided to the first gating module 114.

[0068] The first gating module 114 may include: a second gating transistor Q2. A control end of the second gating transistor Q2 is coupled to the first bias module 112, a first end of the second gating transistor Q2 is coupled to the first voltage source U1, and a second end of the second gating transistor Q2 is coupled to the second charging control unit 120.

[0069] Specifically, when receiving the first bias voltage, the second gating transistor Q2 is gated, so that the first voltage source U1 can act on the second charging control unit 120.

[0070] It should be noted that Figure 2 shows 8 pins of the second gating transistor Q2. Among them, pin 4 is used as the control end, pins 1, 2, and 3 are used as the first end, and pins 5, 6, 7, and 8 are used as the second end.

[0071] As described above, when the charging branch 122 is gated, a charging operation is performed, and when the power supply branch 124 is gated, a normal power supply operation is carried out.

[0072] Based on this, in this embodiment, the equivalent resistance of the charging branch 122 is greater than the equivalent resistance of the power supply branch 124, and when the power supply branch 124 is gated, the charging branch 122 is made in a short - circuit state to disconnect the charging branch 122.

[0073] In other words, after the charging is completed, the power supply branch 124 is gated, while the charging branch 122 is in a short-circuit state, and the equivalent resistance of the charging branch 122 is greater than that of the power supply branch 124. Therefore, after the power supply branch 124 is turned on, there is basically no additional loss, achieving low-power supply.

[0074] In this embodiment, the second charging control unit 120 can satisfy at least one or more of the following:

[0075] The charging branch 122 includes a charging resistor R21. The first end of the charging resistor R21 is respectively coupled to the first charging control unit 110 and the power supply branch 124, and the second end of the charging resistor R21 is respectively coupled to the power supply branch 124 and the energy storage unit 130.

[0076] In this embodiment, the charging resistor R21 can be adjusted according to different usage scenarios to limit the current through the charging resistor R21 and reduce the inrush current.

[0077] The power supply branch 124 may include: a second bias module 1242 and a second gating module 1244, where: the second bias module 1242 is respectively coupled to the first charging control unit 110, the second gating module 1244, and the charging branch 122, and is configured to provide a second bias voltage to the second gating module 1244 based on the first voltage source U1 when the second control signal S2 is in the second state; the second gating module 1244 is configured to be in a gated state in response to the second bias voltage and the first voltage source U1.

[0078] Specifically, the second bias module 1242 can obtain a second bias voltage based on the first voltage source U1 (for example, by dividing the voltage of the second voltage source U1 to obtain the second bias voltage). When the second control signal S1 is in the second state, the first voltage source U1 can act, so that the second gating module 1244 is gated, and then the second charging control unit 120 is gated, and the power supply operation can be performed.

[0079] And since the second gating module 1244 is gated when the second control signal S2 is in the second state, and the power supply branch 122 is turned off, the power supply time can be controlled.

[0080] In this embodiment, the power supply branch 124 can satisfy at least one or more of the following:

[0081] The second bias module 1242 includes: a third bias resistor R22, a fourth bias resistor R23 and a third selection transistor Q3, wherein the first end of the third bias resistor R22 is coupled to the first charging control unit 110 and the charging branch 124 respectively, and the second end of the third bias resistor R22 is coupled to the first end of the fourth bias resistor R24 ​​and the control end of the second selection module 1244 respectively; the second end of the fourth bias resistor R24 ​​is coupled to the first end of the third selection transistor Q3; the control end of the third selection transistor Q3 is suitable for inputting the second control signal S2, and the second end of the third selection transistor Q3 is grounded.

[0082] In other words, the second bias module 1242 may include a voltage divider branch, which is composed of a third bias resistor R22 and a fourth bias resistor R23, thereby providing a second bias voltage for the control terminal of the second gating module 1244. In this way, when the second control signal S2 at the control terminal of the third gating transistor Q3 is in the second state, the second bias voltage can be provided to the second gating module 1244.

[0083] In this embodiment, the second selection module 1244 may include: a fourth selection transistor Q4, the control end of the fourth selection transistor Q4 is coupled to the second bias module 1242, the first end of the fourth selection transistor Q4 is respectively coupled to the first charging control unit 110, the charging branch 122 and the second bias module 1242, and the second end of the fourth selection transistor Q4 is respectively coupled to the energy storage unit 130 and the charging branch 122 (that is, the second selection module 1244 and the charging branch 122 are connected in parallel, and the two are turned on in time sharing).

[0084] Specifically, when receiving the second bias voltage, the fourth selection transistor Q4 is selected, so that the charging branch 122 is disconnected, and the first voltage source U1 can act on the subsequent circuit.

[0085] It should be pointed out that Figure 2 The diagram shows eight pins of the fourth selection transistor Q4, wherein pin 4 is used as a control terminal, pins 1, 2 and 3 are used as first terminals, and pins 5, 6, 7 and 8 are used as second terminals.

[0086] Moreover, the parallel connection scheme in this solution has lower power consumption and faster recovery time compared with the traditional NTC thermistor. Moreover, the fourth selection transistor Q4 can completely bypass the charging resistor R21 after being turned on, thereby reducing continuous loss.

[0087] In addition, this solution may be more flexible because the control circuit can precisely control the turn-on time. It combines the advantages of the charging resistor R21 and the fourth gating transistor Q4. There is a resistor to limit the inrush current, and the fourth gating transistor Q4 reduces the subsequent power consumption. This combination may simplify the design, reduce the need for a complex soft-start circuit, or achieve a balance between cost and reliability.

[0088] Moreover, the charging resistor R21 is easy to replace, while the fourth gating transistor Q4 provides an automatic switching function, which may be more convenient during maintenance or debugging. If the circuit board space is limited, using the combination of the charging resistor R21 and the fourth gating transistor Q4 may save more space than some other solutions.

[0089] Or, in terms of cost, if the combination of the charging resistor R21 and the fourth gating transistor Q4 is more economical than a dedicated soft-start chip or NTC.

[0090] In addition, active control + dynamic path switching is significantly superior to traditional passive solutions in terms of power consumption, response speed, and maintainability, while maintaining low cost and high compatibility.

[0091] In this embodiment, the energy storage unit 130 may include: a first energy storage capacitor C1 and a second energy storage capacitor C2. The first ends of the first energy storage capacitor C1 and the second energy storage capacitor C2 are both coupled to the output terminal of the second charging control unit 120, and the second ends of the first energy storage capacitor C1 and the second energy storage capacitor C2 are both grounded.

[0092] In some embodiments, the parameters of the first energy storage capacitor C1 and the second energy storage capacitor C2 are the same, so the charging completion times of the two are the same.

[0093] In some embodiments, the energy storage unit 130 may include only one of the first energy storage capacitor C1 and the second energy storage capacitor C2.

[0094] In this embodiment, to further improve the effect of the protection circuit in suppressing the inrush current, then refer to Figure 2 , the protection circuit 100 may further include:

[0095] First filter capacitors C3 and C4, disposed at the input terminal of the first charging control unit 110 and coupled to the first voltage source U1.

[0096] By setting the first filter capacitors C3 and C4, the high-frequency noise in the first voltage source U1 can be removed.

[0097] A second filter capacitor C5, disposed at the output terminal of the second charging control unit 120.

[0098] By setting the second filter capacitor C4, the high-frequency noise in the second voltage source U2 can be removed.

[0099] A first current-limiting resistor R3, a first end of the first current-limiting resistor R3 is adapted to input the first control signal S1, and a second end of the first current-limiting resistor R3 is coupled to the first charging control unit 110.

[0100] By setting the first current-limiting resistor R3, a current-limiting effect can be achieved, and the operation safety of the first charging control unit 110 can be improved.

[0101] A second current-limiting resistor R4, a first end of the second current-limiting resistor R4 is adapted to input the second control signal S2, and a second end of the second current-limiting resistor Q4 is coupled to the second charging control unit 120.

[0102] By setting the second current-limiting resistor R4, a current-limiting effect can be achieved, and the operation safety of the second charging control unit 120 can be improved.

[0103] In addition, Figure 2 the input end of the protection circuit 100 is also shown (for example, Figure 2 the shown three-terminal device), and diodes D1 and D2 that are disposed between the input end of the protection circuit 100 and the first charging control unit 110 and are connected in parallel.

[0104] As described in the background art, this circuit can be used in different scenarios for power supply.

[0105] Based on this, then refer to Figure 1 and Figure 2 , refer to Figure 3 , wherein, Figure 3 is a schematic structural diagram of a voltage conversion unit in an embodiment of the present invention. The protection circuit 100 may further include: a voltage conversion unit 140, coupled to an output end of the second charging control unit 120, and configured to convert an amplitude of the second voltage source U2 to obtain a power supply voltage Vout.

[0106] In this embodiment, the voltage conversion unit 140 may include: a voltage conversion chip U1, a feedback module (not marked in the figure), and a bootstrap capacitor C63 and a storage inductor L2 disposed at an output end 3 of the voltage conversion chip U1.

[0107] Wherein, an input end 1 and an enable end 2 of the voltage conversion chip U1 are coupled to an output end of the second charging control unit 120, an output end 3 of the voltage conversion chip U1 is respectively coupled to the storage inductor L2 and the feedback module, and is coupled to a bootstrap end 7 of the voltage conversion chip through the bootstrap capacitor C63, and a feedback end 6 of the voltage conversion chip U1 is coupled to a feedback node of the feedback module.

[0108] The feedback module includes a first feedback resistor R61, a second feedback resistor R62, and a third feedback resistor R63. Among them, the first end of the first feedback resistor R61 is coupled to the output terminal 3 of the voltage conversion chip U1, and the second end of the first feedback resistor R61 is respectively coupled to the first end of the second feedback resistor R62 and connected to the feedback terminal 6 of the voltage conversion chip; the second end of the second feedback resistor R62 is coupled to the first end of the third feedback resistor R63, and the second end of the third feedback resistor R63 is grounded.

[0109] Specifically, in response to the electrical energy on the energy storage unit 130, the voltage conversion chip U1 can output a supply voltage Vout through the output terminal 3. During this process, the feedback module composed of the first feedback resistor R61, the second feedback resistor R62, and the third feedback resistor R63 can perform voltage sampling (wherein the connection node of the second feedback resistor R62 and the third feedback resistor R63 serves as the feedback node), so that the voltage output to the feedback terminal 6 is the voltage drop across the third feedback resistor R63.

[0110] Then, by comparing the voltage drop across the third feedback resistor R63 and the built-in reference voltage, the value of the supply voltage Vout is adjusted until the voltage drop across the third feedback resistor R63 is the same as the built-in reference voltage, achieving a stable output.

[0111] In this embodiment, then refer to Figure 3 , the voltage conversion unit 140 may include a first filtering branch composed of a first inductor L1, a third filtering capacitor C61, a fourth filtering capacitor C62, and a third current-limiting resistor R64. Among them, the first end of the first inductor L1 is coupled to the output terminal of the second charging control unit 120, and the second end of the first inductor L1 is respectively coupled to the first ends of the third filtering capacitor C61, the fourth filtering capacitor C62, and the third current-limiting resistor R64, and the input terminal 1 of the voltage conversion chip U1 is respectively coupled; the second ends of the third filtering capacitor C61 and the fourth filtering capacitor C62 are grounded; the second end of the third current-limiting resistor R64 is connected to the enable terminal 2 of the voltage conversion chip U1. And

[0112] The energy storage capacitor C64 is respectively coupled to the second end of the energy storage inductor L2 and the output terminal.

[0113] A second filtering branch composed of a fifth filtering capacitor C65, a sixth filtering capacitor C66, and a second inductor L3, wherein the first ends of the fifth filtering capacitor C65, the sixth filtering capacitor C66, and the second inductor L3 are respectively coupled and coupled to the second end of the energy storage inductor L2, the second ends of the fifth filtering capacitor C65 and the sixth filtering capacitor C66 are grounded and coupled to the ground terminal 4 of the voltage conversion chip U1; the second end of the second inductor L3 serves as the output terminal.

[0114] Correspondingly, it further includes: a diode D3 coupled between the ground terminal 4 of the voltage conversion chip U1 and the energy storage inductor L2.

[0115] In addition, it further includes a switching capacitor C69 connected to the switching node 8 of the voltage conversion chip U1.

[0116] A comparison resistor R64, a first comparison capacitor C67, and a second comparison capacitor C68 between the comparison terminal 5 of the voltage conversion chip U1 and the ground.

[0117] For the convenience of understanding and illustration, through Figures 1 to 3 , briefly describe the working mechanism of the protection circuit in this solution.

[0118] When the first control signal S1 is in the second state, the first gating transistor Q1 is turned on. Then, based on the first bias resistor R11 and the second bias resistor R12, a first bias voltage can be provided for the second gating transistor Q2, so that the second gating transistor Q2 is gated.

[0119] At this time, the second control signal S2 is in the first state, then the third gating transistor Q3 is in the off state, making the fourth gating transistor Q4 in the gated state. Thus, the charging resistor R21 is connected to the circuit, and in this way, the first voltage source U1 can charge the first energy storage capacitor C1 and the second energy storage capacitor C2.

[0120] After the charging is completed, make the second control signal S2 in the second state, then the third gating transistor Q3 is turned on. Then, based on the third bias resistor R22 and the fourth bias resistor R23, a second bias voltage can be provided for the fourth gating transistor Q4, so that the fourth gating transistor Q4 is gated, and the charging resistor R21 is short-circuited to achieve low-power supply.

[0121] More specifically, the electrical energy stored in the first energy storage capacitor C1 and the second energy storage capacitor C2 is input to the input terminal 1 of the voltage conversion chip U1. Then, the voltage conversion chip U1 can perform a voltage conversion operation, and during the conversion process, sample the supply voltage Vout, so that the voltage conversion chip U1 outputs a stable supply voltage Vout.

[0122] It can be understood that the above describes multiple embodiment solutions provided by the embodiments of the present disclosure. The various alternative ways introduced in each embodiment solution can be combined with each other and cross-referenced without conflict, so as to extend multiple possible embodiment solutions, and these can all be considered as the embodiment solutions disclosed and made public by the present disclosure.

[0123] The present invention also provides an electronic device, which may include: the protection circuit as described in any of the foregoing embodiments.

[0124] In some embodiments, the electronic device may include: a record player, a decoder, a network player, an adapter-powered device, etc.

[0125] Although the embodiments of the present disclosure are disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. A protection circuit, characterized in that, It includes: A first charging control unit, a second charging control unit, and an energy storage unit, where: The first charging control unit is respectively coupled to the second charging control unit and a first voltage source, and is configured to, in response to a first control signal, select a path between the first voltage source and the second charging control unit; The second charging control unit is coupled to the energy storage unit and has a charging branch and a power supply branch. Wherein, when the second control signal is in a first state, the charging branch is selected and the power supply branch is disconnected; and when the second control signal is in a second state, the power supply branch is selected and the charging branch is disconnected; The energy storage unit is configured to, when the charging branch is selected, perform an energy storage operation based on the first voltage source to generate a second voltage source; and when the power supply branch is selected, perform a power supply operation through the second voltage source.

2. The protection circuit according to claim 1, wherein The first charging control unit includes: a first biasing module and a first selection module, where: The first biasing module is coupled to the first voltage source and the first selection module, and is configured to, when the first control signal is in a second state, provide a first bias voltage to the first selection module based on the first voltage source; The first selection module is configured to be in a selected state in response to the first bias voltage and the first voltage source.

3. The protection circuit according to claim 2, wherein The first charging control unit satisfies at least one or more of the following: The first biasing module includes: a first biasing resistor, a second biasing resistor, and a first selection transistor. Wherein, a first end of the first biasing resistor is coupled to the first voltage source, and a second end of the first biasing resistor is respectively coupled to a first end of the second biasing resistor and a control end of the first selection module; a second end of the second biasing resistor is coupled to a first end of the first selection transistor; a control end of the first selection transistor is adapted to input the first control signal, and a second end of the first selection transistor is grounded; The first selection module includes: a second selection transistor. A control end of the second selection transistor is coupled to the first biasing module, a first end of the second selection transistor is coupled to the first voltage source, and a second end of the second selection transistor is coupled to the second charging control unit.

4. The protection circuit according to claim 1, wherein At an initial moment, the first control signal and the second control signal are in the first state, and after a preset moment when the first control signal is in the second state, both the first control signal and the second control signal are in the second state; Wherein: The preset moment is determined based on the first voltage source and the energy storage unit.

5. The protection circuit according to claim 1, characterized in that, The equivalent resistance of the charging branch is greater than the equivalent resistance of the power supply branch, and when the power supply branch is selected, the charging branch is disconnected by short - circuiting the charging branch.

6. The protection circuit according to claim 1 or 5, characterized in that The second charging control unit satisfies at least one or more of the following: The power supply branch includes: a second bias module and a second gating module, where: the second bias module is respectively coupled to the first charging control unit, the second gating module, and the charging branch, and is configured to provide a second bias voltage to the second gating module based on the first voltage source when the second control signal is in a second state; the second gating module is configured to be in a gated state in response to the second bias voltage and the first voltage source; The charging branch includes a charging resistor, a first end of the charging resistor is respectively coupled to the first charging control unit and the power supply branch, and a second end of the charging resistor is respectively coupled to the power supply branch and the energy storage unit.

7. The protection circuit according to claim 6, wherein The power supply branch satisfies at least one or more of the following: The second bias module includes: a third bias resistor, a fourth bias resistor, and a third gating transistor, where a first end of the third bias resistor is respectively coupled to the first charging control unit and the charging branch, a second end of the third bias resistor is respectively coupled to a first end of the fourth bias resistor and a control end of the second gating module; a second end of the fourth bias resistor is coupled to a first end of the third gating transistor; a control end of the third gating transistor is adapted to input the second control signal, and a second end of the third gating transistor is grounded; The second gating module includes: a fourth gating transistor, a control end of the fourth gating transistor is coupled to the second bias module, a first end of the fourth gating transistor is respectively coupled to the first charging control unit, the charging branch, and the second bias module, and a second end of the fourth gating transistor is respectively coupled to the energy storage unit and the charging branch.

8. The protection circuit according to claim 1, characterized in that, It also satisfies at least one or more of the following: A first filter capacitor is provided at an input end of the first charging control unit and is coupled to the first voltage source; A second filter capacitor is provided at an output end of the second charging control unit; A first current limiting resistor, a first end of the first current limiting resistor is adapted to input the first control signal, and a second end of the first current limiting resistor is coupled to the first charging control unit; A second current limiting resistor, a first end of the second current limiting resistor is adapted to input the second control signal, and a second end of the second current limiting resistor is coupled to the second charging control unit; A voltage conversion unit is coupled to an output end of the second charging control unit and is configured to convert an amplitude of the second voltage source to obtain a supply voltage.

9. The protection circuit according to claim 8, characterized in that The voltage conversion unit includes: a voltage conversion chip, a feedback module, and a bootstrap capacitor and an energy storage inductor provided at an output end of the voltage conversion chip; Wherein, an input end and an enable end of the voltage conversion chip are coupled to an output end of the second charging control unit, an output end of the voltage conversion chip is respectively coupled to the energy storage inductor and the feedback module, and is coupled to a bootstrap end of the voltage conversion chip through the bootstrap capacitor, and a feedback end of the voltage conversion chip is coupled to a feedback node of the feedback module; The feedback module includes a first feedback resistor and a second feedback resistor. Among them, a first end of the first feedback resistor is coupled to an output end of the voltage conversion chip, a second end of the first feedback resistor is respectively coupled to a first end of the second feedback resistor and is connected to a feedback end of the voltage conversion chip; a second end of the second feedback resistor is grounded.

10. An electronic device, characterized in that, Comprising: The protection circuit according to any one of claims 1 to 9.

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