Boost protection circuit and electronic equipment

Abstract

The utility model provides a boost protection circuit and electronic equipment, and belongs to the technical field of electronics. The circuit comprises a short-circuit protection unit, an inductor, a switch unit and a boost control unit, the first end of the short-circuit protection unit is used for being connected with the positive electrode of the energy storage device so as to input a first working voltage, the first end of the short-circuit protection unit is further connected with the first end of the inductor, the first end of the switch unit and the second end of the switch unit, and the second end of the short-circuit protection unit is connected with the third end of the switch unit; the second end of the inductor is connected with the external device and the first end of the boost control unit. The fourth end of the switch unit is connected with the second end of the boost control unit; and the switch unit is used for being switched on or switched off under the action of the short-circuit protection unit and supplying power to the boost control unit under the condition that the switch unit is switched on. Based on the circuit which is simple in design and low in cost, the effect of improving the practicability and reliability of boost protection can be achieved.

Description

Technical Field

[0001] This application relates to the field of electronic technology, and more specifically, to a boost protection circuit and electronic device. Background Technology

[0002] With the widespread use of electronic devices, various non-isolated boost circuits have emerged. These non-isolated boost circuits typically include an inductor and a synchronization diode between the input and output circuits. Therefore, in the event of a short circuit at the output of a non-isolated circuit, there is no component isolation between the input and output circuits, posing a risk of circuit damage.

[0003] In related technologies, typical non-isolated boost converter circuits usually add a resettable fuse at the input for short-circuit protection. Specifically, when a short circuit occurs in the boost converter circuit, the current in the circuit increases, causing the resettable fuse to trip. When the short circuit is cleared, the current in the circuit decreases, and the resettable fuse turns back on. Alternatively, short-circuit protection can also be achieved by incorporating a corresponding BUCK chip in the non-isolated boost converter circuit.

[0004] However, in related technologies, the solution using a self-resetting fuse will continuously switch between the conducting and disconnecting states when the short circuit is not cleared. The solution using a BUCK chip has a more complex circuit design and higher cost. Utility Model Content

[0005] The purpose of this application is to provide a boost protection circuit and electronic device that can improve the practicality and reliability of boost protection based on a simple and low-cost circuit design.

[0006] The embodiments of this application are implemented as follows:

[0007] A first aspect of this application provides a boost protection circuit, the circuit comprising: a short-circuit protection unit, an inductor, a switching unit, and a boost control unit.

[0008] The first terminal of the short-circuit protection unit is used to connect to the positive terminal of the energy storage device to input a first operating voltage. The first terminal of the short-circuit protection unit is also connected to the first terminal of the inductor, the first terminal of the switching unit, and the second terminal of the switching unit. The second terminal of the short-circuit protection unit is connected to the third terminal of the switching unit. The short-circuit protection unit is used to turn off when the circuit is short-circuited to cut off the power loop that outputs the first operating voltage to the external device. The short-circuit protection unit turns on or off based on the output voltage of the circuit.

[0009] The second end of the inductor is connected to the first end of the external device and the boost control unit, respectively.

[0010] The fourth terminal of the switching unit is connected to the second terminal of the boost control unit; the switching unit is used to turn on or off under the action of the short-circuit protection unit, and to supply power to the boost control unit when the switching unit is on; the boost control unit is used to control the inductor to store energy or to discharge to the external device.

[0011] Optionally, the short-circuit protection unit includes: a disconnecting switch and a switching module;

[0012] The first terminal of the disconnect switch is connected to the first terminal of the inductor, the second terminal of the disconnect switch is connected to the first terminal of the switch module, the third terminal of the disconnect switch is used to input the electrical energy output by the inductor, and the fourth terminal of the disconnect switch is connected to the second terminal of the switch module; the disconnect switch is used to convert the first operating voltage into a second operating voltage and output the second operating voltage to the switch module.

[0013] The third terminal of the switch module is connected to the third terminal of the switch unit, and the fourth terminal of the switch module is used to connect to the negative terminal of the energy storage device; the switch module is used to turn off when the circuit is short-circuited to cut off the power loop.

[0014] Optionally, the switching module includes at least: a first diode, a second diode, a first resistor, a second resistor, a third resistor, a fourth resistor, and a first switching transistor;

[0015] The first end of the first resistor is connected to the second end of the disconnecting switch, and the second end of the first resistor is connected to the first terminal of the first switching transistor, the first end of the second resistor, and the negative terminal of the first diode.

[0016] The second terminal of the first switching transistor is connected to the second terminal of the second resistor, the cathode of the first diode, and the first terminal of the third resistor, respectively. The third terminal of the first switching transistor is connected to the second terminal of the third resistor, the third terminal of the switching unit, and the first terminal of the fourth resistor, respectively.

[0017] The negative terminal of the second diode is connected to the fourth terminal of the disconnecting switch, and the positive terminal of the second diode is connected to the second terminal of the fourth resistor; the second diode is used to disconnect the circuit when it is short-circuited.

[0018] Optionally, the first switching transistor is an N-channel switching transistor; there are multiple third resistors, and the multiple third resistors are connected in parallel.

[0019] Optionally, the switching unit includes at least: a third diode, a fourth diode, and a second switching transistor;

[0020] The positive terminal of the third diode is connected to the first terminal of the short-circuit protection unit and the first terminal of the second switching transistor, respectively; the negative terminal of the third diode is connected to the second terminal of the short-circuit protection unit and the positive terminal of the fourth diode, respectively; and the negative terminal of the fourth diode is connected to the second terminal of the second switching transistor.

[0021] The third terminal of the second switching transistor is connected to the third terminal of the short-circuit protection unit, and the first terminal of the second switching transistor is grounded; the second switching transistor is used to output the working voltage to the boost control unit under the action of the short-circuit protection unit.

[0022] Optionally, the switching unit further includes: a fifth resistor, a sixth resistor, a first capacitor, and a second capacitor;

[0023] The fifth resistor and the sixth resistor are connected in series between the first terminal of the short-circuit protection unit and the positive terminal of the third diode;

[0024] The first capacitor is connected in parallel with the third diode, and the second capacitor is connected between the first terminal of the second switching transistor and the positive terminal of the third diode.

[0025] Optionally, the boost protection circuit further includes: an anti-backflow unit;

[0026] The first end of the anti-backflow unit is connected to the second end of the inductor and the first end of the boost control unit, respectively, and the second end of the anti-backflow unit is used to connect to the external device.

[0027] Optionally, the anti-backflow unit includes at least one fifth diode;

[0028] The positive terminal of each of the fifth diodes is connected to the second terminal of the inductor, and the negative terminal of each of the fifth diodes is used to connect to the external device.

[0029] Optionally, the boost protection circuit further includes: a filter unit;

[0030] The first end of the filter unit is connected to the third end of the switch unit, and the second end of the filter unit is connected to the first end of the inductor.

[0031] A second aspect of this application provides an electronic device, the electronic device comprising: any of the boost protection circuits described in the first aspect above.

[0032] The beneficial effects of the embodiments of this application include:

[0033] This application provides a boost protection circuit, which includes a short-circuit protection unit, an inductor, a switching unit, and a boost control unit. Specifically, the first terminal of the short-circuit protection unit is connected to the positive terminal of an energy storage device to receive a first operating voltage. The first terminal of the short-circuit protection unit is also connected to the first terminal of the inductor, the first terminal of the switching unit, and the second terminal of the switching unit. The second terminal of the short-circuit protection unit is connected to the third terminal of the switching unit. The second terminal of the inductor is connected to both the external device and the first terminal of the boost control unit. The fourth terminal of the switching unit is connected to the second terminal of the boost control unit.

[0034] The boost protection circuit can supply power to the boost control unit via the switching unit when there is no short circuit, allowing the boost control unit to control the charging and discharging of the inductor to achieve the purpose of boosting the voltage. Furthermore, in the event of a short circuit, the circuit can disconnect the power loop by causing the short-circuit protection unit to trip, preventing the current generated based on the first operating voltage and / or the inductor output voltage from forming a complete return path, thus achieving the purpose of short-circuit protection.

[0035] Furthermore, since the short-circuit protection unit is specifically designed to turn on or off based on the circuit's output voltage, if the circuit remains in a short-circuit state and the output voltage remains at a low level, the short-circuit protection unit will remain in the off state. This avoids the problem of the short-circuit protection unit switching back and forth between the on and off states when the short circuit has not been resolved.

[0036] In addition, since the circuit provided in this application embodiment only requires simple components to achieve the purpose of boosting voltage and short-circuit protection, the circuit also has the advantages of simple design and low cost.

[0037] In this way, the practicality and reliability of boost protection can be improved based on a simple and low-cost circuit design. Attached Figure Description

[0038] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of the structure of the first boost protection circuit provided in the embodiments of this application;

[0040] Figure 2 This is a schematic diagram of the structure of the second boost protection circuit provided in the embodiments of this application;

[0041] Figure 3 A schematic diagram of the structure of the third boost protection circuit provided in the embodiments of this application;

[0042] Figure 4 This is a schematic diagram of the structure of the fourth boost protection circuit provided in the embodiments of this application;

[0043] Figure 5 This is a schematic diagram of the structure of the fifth boost protection circuit provided in the embodiments of this application;

[0044] Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0046] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0047] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0048] In the description of this application, it should be noted that the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0049] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0050] In typical non-isolated boost converter circuits, a resettable fuse is usually added to the input terminal for short-circuit protection. Specifically, when a short circuit occurs in the boost converter circuit, the current increases, causing the resettable fuse to trip. When the short circuit is cleared, the current decreases, and the resettable fuse turns back on. Alternatively, short-circuit protection can also be achieved by incorporating a corresponding BUCK chip into the non-isolated boost converter circuit.

[0051] However, in related technologies, the solution using a self-resetting fuse will continuously switch between the conducting and disconnecting states when the short circuit is not cleared. The solution using a BUCK chip has a more complex circuit design and higher cost.

[0052] To address this, this application provides a boost protection circuit, which includes a short-circuit protection unit, an inductor, a switching unit, and a boost control unit. Specifically, the first terminal of the short-circuit protection unit is connected to the positive terminal of the energy storage device to receive a first operating voltage. The first terminal of the short-circuit protection unit is also connected to the first terminal of the inductor, the first terminal of the switching unit, and the second terminal of the switching unit. The second terminal of the short-circuit protection unit is connected to the third terminal of the switching unit. The second terminal of the inductor is connected to the external device and the first terminal of the boost control unit. The fourth terminal of the switching unit is connected to the second terminal of the boost control unit. This design, based on a simple and low-cost circuit, improves the practicality and reliability of boost protection.

[0053] This application uses a boost protection circuit applied in electronic devices to protect non-isolated boost modules as an example for illustration. However, it does not imply that this application's embodiments can only be applied to electronic devices for short-circuit protection of non-isolated boost modules.

[0054] The boost protection circuit provided in the embodiments of this application will be explained in detail below.

[0055] Figure 1 A schematic diagram of a boost protection circuit provided in this application. See also... Figure 1 This application provides a boost protection circuit 100, which includes a short-circuit protection unit 101, an inductor L, a switching unit 102, and a boost control unit 103.

[0056] The first end of the short-circuit protection unit 101 is used to connect to the positive terminal of the energy storage device to input the first working voltage. The first end of the short-circuit protection unit 101 is also connected to the first end of the inductor L, the first end of the switching unit 102, and the second end of the switching unit 102. The second end of the short-circuit protection unit 101 is connected to the third end of the switching unit 102.

[0057] The second end of the inductor L is connected to the first end of the external device and the boost control unit 103, respectively.

[0058] The fourth terminal of the switching unit 102 is connected to the second terminal of the boost control unit 103.

[0059] The short-circuit protection unit 101 is used to turn off when the circuit is short-circuited, thereby cutting off the power circuit that outputs the first operating voltage to the external device.

[0060] The switching unit 102 is used to turn on or off under the action of the short-circuit protection unit 101, and to supply power to the boost control unit 103 when the switching unit 102 is on.

[0061] The boost control unit 103 is used to control the inductor L to store energy or to discharge to the external device.

[0062] Optionally, the first operating voltage may refer to the voltage output from a lithium battery or other possible energy storage device to the circuit 100 and the external device, and the first operating voltage may power the components in the circuit 100 and / or the external device.

[0063] Generally, the external device can be any possible electrical load, such as a display device or output device in an electronic device. This application does not limit this.

[0064] And this power circuit can refer to... Figure 1 The first operating voltage input at the IN+ terminal flows through the inductor L, is output from the OUT+ terminal to the positive terminal of the external device, then flows from the negative terminal of the external device to the short-circuit protection unit 101, and finally returns to the IN- terminal via the current return path.

[0065] Furthermore, from Figure 1 As can be seen, the third terminal of the short-circuit protection unit 101 is also connected to the IN- terminal. In this embodiment, the IN+ terminal and the IN- terminal can refer to the positive and negative terminals of the energy storage device, respectively.

[0066] Optionally, the short-circuit protection unit 101 can be specifically used to turn on when the circuit 100 is not short-circuited, so that the power loop can form a path, thereby allowing the energy storage device to supply power to external devices through the circuit 100. Furthermore, the short-circuit protection unit 101 can also be used to turn off when the circuit 100 is short-circuited, so that the power loop is disconnected, thereby preventing the energy storage device from supplying power to external devices through the circuit 100. In this way, it can be ensured that the short-circuit protection unit 101 remains continuously off when the circuit 100 is short-circuited, thus achieving the short-circuit protection function.

[0067] Specifically, the short-circuit protection unit 101 can be turned on or off based on the output voltage of the circuit 100. Normally, when the circuit 100 is not short-circuited, the output voltage is high, and the short-circuit protection unit 101 can remain in the on state. When the circuit 100 is short-circuited, the output voltage decreases, and the short-circuit protection unit 101 can remain in the off state.

[0068] In this embodiment, a short circuit in circuit 100 can refer to the output terminal of circuit 100 (i.e., Figure 1 If the OUT+ terminal shown is short-circuited, the voltage of OUT+ will become very low, or even drop to 0.

[0069] Optionally, the switching unit 102 may include a corresponding switch to realize the function of turning on or off.

[0070] For example, when the first operating voltage is input to the short-circuit protection unit 101, the short-circuit protection unit 101 can output a corresponding turn-on signal to the switching unit 102 to turn on the switching unit 102; however, when the first operating voltage is not input to the short-circuit protection unit 101, the short-circuit protection unit 101 will not output a turn-on signal to the switching unit 102, and the switching unit 102 will remain off.

[0071] Optionally, the boost control unit 103 can be any device or component that enables the circuit 100 to perform the boost function. Generally, it is only necessary to ensure that the boost control unit 103 can enable the inductor L to alternately enter the charging state and the discharging state. This application embodiment does not limit this.

[0072] In this embodiment, the boost control unit 103 may include a boost control chip and a corresponding switching transistor. Specifically, the boost control chip may output a pulse width modulation (PWM) signal to the switching transistor to control the switching transistor to continuously turn on and off, thereby causing the inductor L to switch back and forth between charging and discharging states.

[0073] It is worth noting that, in one possible approach, when the switching transistor in the boost control unit 103 is turned on, current can flow through the inductor L, and the inductor L begins to store energy. At this time, the right side of the inductor L is conductive, and the current generated based on the first operating voltage flows back to the ground terminal through the inductor L, where the inductor L stores energy. When the switching transistor in the boost control unit 103 is turned off, the inductor L begins to discharge. Since the current flowing through the inductor L cannot change abruptly, that is, the discharge process of the inductor L is slow. The first operating voltage and the voltage generated by the inductor L are superimposed before power is supplied to the external device. In this way, the output voltage of the inductor L will be higher than the input voltage of the inductor L, thus enabling the boost function based on the inductor L.

[0074] Optionally, the circuit 100 may also include a diode and an output capacitor for energy storage and discharge in conjunction with the inductor L, or a corresponding diode and output capacitor may be provided in an external device to cooperate with the inductor L to achieve voltage boosting. This application does not limit this aspect.

[0075] It should be understood that, in order to better illustrate the circuit 100 provided in the embodiments of this application, the working principle of the circuit 100 will be explained and described below:

[0076] In the sleep state where the first operating voltage is not input, the short-circuit protection unit 101 will not output a conduction signal to the switching unit 102, the switching unit 102 remains off, and the boost control unit 103 does not operate. At the same time, the inductor L does not store energy, and there is no voltage output at the OUT+ terminal.

[0077] When the first operating voltage is input, the short-circuit protection unit 101 powers on and outputs a conduction signal to the switching unit 102, causing the switching unit 102 to conduct. The switching unit 102 then outputs the first operating voltage to the boost control unit 103. Since this first operating voltage is also output to the inductor L, the inductor L can begin charging and discharging after the boost control unit 103 powers on. Simultaneously, the short-circuit protection unit 101 also powers on upon receiving the first operating voltage. If no short circuit occurs in the circuit 100, the short-circuit protection unit 101 will maintain the power loop conduction. At this time, the circuit 100 can be in a stable and normal boost state.

[0078] If a short circuit occurs in circuit 100, the short-circuit protection unit 101 will disconnect the power loop, preventing the current generated based on the first operating voltage and / or the voltage output from inductor L from forming a complete current return path. Thus, circuit 100 will no longer output power to external devices, achieving the short-circuit protection function. It is worth noting that, in the absence of a short circuit, circuit 100 can supply power to the boost control unit 103 via the switching unit 102, allowing the boost control unit 103 to control the charging and discharging of inductor L to achieve the purpose of boosting the voltage. Furthermore, in the event of a short circuit, circuit 100 can disconnect the power loop by opening the short-circuit protection unit 101, preventing the current generated based on the first operating voltage and / or the voltage output from inductor L from forming a complete current return path, thereby achieving the purpose of short-circuit protection.

[0079] In this embodiment, a short-circuit protection unit 101, an inductor L, a switching unit 102, and a boost control unit 103 are provided in the boost protection circuit 100. Specifically, the first terminal of the short-circuit protection unit 101 is connected to the positive terminal of the energy storage device to input a first operating voltage. The first terminal of the short-circuit protection unit 101 is also connected to the first terminal of the inductor L, the first terminal of the switching unit 102, and the second terminal of the switching unit 102. The second terminal of the short-circuit protection unit 101 is connected to the third terminal of the switching unit 102. The second terminal of the inductor L is connected to the external device and the first terminal of the boost control unit 103. The fourth terminal of the switching unit 102 is connected to the second terminal of the boost control unit 103.

[0080] The boost protection circuit 100 can supply power to the boost control unit 103 via the switching unit 102 when there is no short circuit, so that the boost control unit 103 controls the charging and discharging of the inductor L to achieve the purpose of boosting the voltage. Furthermore, in the event of a short circuit, the circuit 100 can disconnect the short-circuit protection unit 101 to cut off the power loop, preventing the current generated based on the first operating voltage and / or the output voltage of the inductor L from forming a complete return path, thus achieving the purpose of short-circuit protection.

[0081] Furthermore, since the short-circuit protection unit 101 is specifically turned on or off based on the output voltage of the circuit 100, if the circuit 100 remains in a short-circuit state and its output voltage remains at a low level, the short-circuit protection unit 101 will remain in an open state. This avoids the problem of the short-circuit protection unit 101 switching back and forth between the on and off states when the circuit 100 is not de-circuited.

[0082] In addition, since the circuit 100 provided in this application embodiment only needs to use simple components to achieve the purpose of boosting voltage and short-circuit protection, the circuit 100 also has the advantages of simple design and low cost.

[0083] In this way, the practicality and reliability of boost protection can be improved based on a simple and low-cost circuit design.

[0084] In one possible implementation, see [link to relevant documentation]. Figure 2 The short-circuit protection unit 101 includes: disconnecting switch U1 and switch module 1011.

[0085] The first terminal of the disconnecting switch U1 is connected to the first terminal of the inductor L, the second terminal of the disconnecting switch U1 is connected to the first terminal of the switch module 1011, the third terminal of the disconnecting switch U1 is used to input the electrical energy output by the inductor L, and the fourth terminal of the disconnecting switch U1 is connected to the second terminal of the switch module 1011.

[0086] The third terminal of the switch module 1011 is connected to the third terminal of the switch unit 102, and the fourth terminal of the switch module 1011 is used to connect to the negative terminal of the energy storage device.

[0087] Optionally, the disconnecting switch U1 can be any possible isolation device, such as optocoupler isolation, electromagnetic isolation, digital isolation, etc.

[0088] In this embodiment, the isolating switch U1 is used to convert the first operating voltage into a second operating voltage and output the second operating voltage to the switch module 1011.

[0089] Generally, the second operating voltage can be the same as or different from the first operating voltage, and this application embodiment does not limit this. Moreover, although the second operating voltage is generated based on the first operating voltage, the second operating voltage and the first operating voltage are electrically isolated from each other, which can improve the anti-interference capability of the short-circuit protection unit 101.

[0090] Optionally, the third terminal of the switch module 1011 may also be grounded. The switch module 1011 is used to turn off when the circuit is short-circuited, thereby cutting off the power loop. Specifically, the switch module 1011 can be turned on or off based on the output voltage of the circuit 100.

[0091] For example, since the output terminal (OUT+) of circuit 100 is connected to the primary side of disconnecting switch U1, the voltage of OUT+ is relatively large when circuit 100 is not short-circuited. The voltage difference between OUT+ and the third terminal of switch module 1011 is relatively large. At this time, the primary side of disconnecting switch U1 (between the third and fourth terminals of disconnecting switch U1) will form a loop, so that the secondary side of disconnecting switch U1 (between the first and second terminals of disconnecting switch U1) is turned on and outputs the second operating voltage to switch module 1011. Under this condition, switch module 1011 can remain on.

[0092] When circuit 100 is short-circuited, the voltage of OUT+ is small, and the voltage difference between OUT+ and the third terminal of switch module 1011 is small. At this time, the loop of the primary side of disconnect switch U1 (between the third and fourth terminals of disconnect switch U1) is turned off, so that the secondary side of disconnect switch U1 (between the first and second terminals of disconnect switch U1) is turned off and stops outputting the second working voltage to switch module 1011. Under this condition, switch module 1011 can be switched to the open state.

[0093] It is worth noting that this ensures that the short-circuit protection unit 101 remains in the open state when circuit 100 remains in a short-circuit state. This avoids the problem of the short-circuit protection unit 101 switching back and forth between the on and off states when circuit 100 is not released from the short-circuit state. Thus, the practicality and reliability of circuit 100 are improved.

[0094] In one possible implementation, see [link to relevant documentation]. Figure 2 The switching module 1011 includes at least: a first diode D1, a second diode D2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, and a first switching transistor Q1;

[0095] The first end of the first resistor R1 is connected to the second end of the disconnecting switch U1, and the second end of the first resistor R1 is connected to the first terminal of the first switching transistor Q1, the first end of the second resistor R2, and the negative terminal of the first diode D1.

[0096] The second terminal of the first switching transistor Q1 is connected to the second terminal of the second resistor R2, the negative terminal of the first diode D1, and the first terminal of the third resistor R3, respectively. The third terminal of the first switching transistor Q1 is connected to the second terminal of the third resistor R3, the third terminal of the switching unit 102, and the first terminal of the fourth resistor R4, respectively.

[0097] The cathode of the second diode D2 is connected to the fourth terminal of the disconnecting switch U1, and the anode of the second diode D2 is connected to the second terminal of the fourth resistor R4. Furthermore, the second terminal of the fourth resistor R4 can also be grounded.

[0098] Optionally, the second diode D2 is used to disconnect the circuit when it is short-circuited.

[0099] The first switching transistor Q1 is an N-channel switching transistor, such as an NMOS transistor or an N-channel IGBT.

[0100] Optionally, the second diode D2 can be a steady-state diode.

[0101] Specifically, the first diode D1 and the second diode D2 can be used as clamping diodes to ensure that the first switching transistor Q1 can be turned on and off normally. The first resistor R1, the second resistor R2, and the third resistor R3 can be used as voltage divider resistors, and the fourth resistor R4 can be used as a current limiting resistor.

[0102] In one possible approach, there can be one third resistor R3. Alternatively, there can be multiple third resistors R3 connected in parallel.

[0103] It is worth noting that since the third terminal of the isolating switch U1 is connected to OUT+, when circuit 100 is not short-circuited, the voltage difference between the third and fourth terminals of the isolating switch U1 is greater than the voltage regulation value of the second diode D2. A loop can be formed between the third and fourth terminals of the isolating switch U1, so that the isolating switch U2 outputs the second working voltage to the first resistor R1.

[0104] Furthermore, due to the voltage division effect of the first resistor R1, the second resistor R2, and the third resistor R3, the first switch Q1 can be turned on, thus enabling the power circuit to conduct.

[0105] Meanwhile, the second operating voltage can be transmitted to the switching unit 102 via the first resistor R1, the second resistor R2, and the third resistor R3, thereby enabling the switching unit 102 to conduct and supply power to the boost control unit 103 to achieve the boost function.

[0106] When circuit 100 is short-circuited, the voltage difference between the third and fourth terminals of isolating switch U1 is less than the voltage regulation value of the second diode D2. No current flows through the third and fourth terminals of isolating switch U1, so isolating switch U2 will not output the second operating voltage to the first resistor R1. At this time, the power circuit of circuit 100 is turned off, and switching unit 102 is disconnected and does not supply power to boost control unit 103. Circuit 100 enters a short-circuit protection sleep state.

[0107] In one possible implementation, see [link to relevant documentation]. Figure 3 The switching unit 102 includes at least: a third diode D3, a fourth diode D4, and a second switching transistor Q2.

[0108] The positive terminal of the third diode D3 is connected to the first terminal of the short-circuit protection unit 101 and the first terminal of the second switch Q2, respectively. The negative terminal of the third diode D3 is connected to the second terminal of the short-circuit protection unit 101 and the positive terminal of the fourth diode D4, respectively. The negative terminal of the fourth diode D4 is connected to the second terminal of the second switch Q2.

[0109] The third terminal of the second switch Q2 is connected to the third terminal of the short-circuit protection unit 101, and the first terminal of the second switch Q2 is grounded.

[0110] In this embodiment, the third diode D3 can be used as a clamping diode, and the fourth diode D4 can be used to limit the direction of current flowing to the second terminal of the second switch Q2 based on its own unidirectional conduction characteristics.

[0111] Optionally, the second switch Q2 is used to output the operating voltage to the boost control unit 103 under the action of the short-circuit protection unit 101.

[0112] Optionally, the second switching transistor Q2 can be an NPN transistor.

[0113] It is worth noting that when the short-circuit protection unit 101 has the first operating voltage input and the circuit 100 is not short-circuited, the second operating voltage output by the isolating switch U1 in the short-circuit protection unit 101 is transmitted to the third diode D2 through the first resistor R1, the second resistor R2, and the third resistor R3. The third diode D2 conducts, thereby turning on the second switch Q2, so that the first operating voltage is output to the boost control unit 103 through the first and third terminals of the second switch Q2. When the short-circuit protection unit 101 has the first operating voltage input and the circuit 100 is short-circuited, the isolating switch U1 in the short-circuit protection unit 101 does not output the second operating voltage, so the second switch Q2 remains off, and the boost control unit 103 does not work at this time.

[0114] In one possible implementation, see [link to relevant documentation]. Figure 3 The switching unit 102 also includes: a fifth resistor R5, a sixth resistor R6, a first capacitor C1, and a second capacitor C2.

[0115] The fifth resistor R5 and the sixth resistor R6 are connected in series between the first terminal of the short-circuit protection unit 101 and the positive terminal of the third diode D3.

[0116] The first capacitor C1 is connected in parallel with the third diode D3, and the second capacitor C2 is connected between the first terminal of the second switch Q2 and the positive terminal of the third diode D3.

[0117] Optionally, the fifth resistor R5 and the sixth resistor R6 can be used as current-limiting resistors, and the first capacitor C1 and the second capacitor C2 can be used for voltage regulation and filtering.

[0118] This improves the stability of the switching unit 102.

[0119] In one possible implementation, see [link to relevant documentation]. Figure 4 and Figure 5 The boost protection circuit 100 also includes an anti-backflow unit 104.

[0120] The first end of the anti-backflow unit 104 is connected to the second end of the inductor L and the first end of the boost control unit 103, respectively. The second end of the anti-backflow unit 104 is used to connect to the external device.

[0121] Optionally, the backflow prevention unit 104 can prevent the current output from external devices from flowing back into other components in the circuit 100, which could cause damage to other components.

[0122] In one possible implementation, the anti-backflow unit 104 includes at least one fifth diode.

[0123] The positive terminal of each fifth diode is connected to the second terminal of the inductor L, and the negative terminal of each fifth diode is used to connect to the external device.

[0124] For example, see continue. Figure 4 and Figure 5 The backflow prevention unit 104 may include two fifth diodes D5 connected in parallel. The specific connection relationship is shown in the figure, and will not be described in detail here.

[0125] For example, the anti-backflow unit 104 may also include a fifth diode D5, in which case the rated current of the fifth diode D5 can be relatively large.

[0126] For example, see [link to previous article] Figure 4 and Figure 5 The boost protection circuit 100 may also include a third capacitor C3. Figure 4 and Figure 5 The third capacitor C3 shown can be placed in the anti-backflow unit 104, but in actual applications, the third capacitor C3 can also be placed outside the anti-backflow unit 104 and connected to the second end of the anti-backflow unit 104. This application embodiment does not limit this.

[0127] It is worth noting that since each of the fifth diodes D5 has unidirectional conduction characteristics, each of the fifth diodes D5 can serve as an anti-backflow diode to prevent the electrical energy output from the external device from flowing back into the inductor L and the circuit 100. Additionally, the third capacitor C3 can also be used as the output capacitor of the circuit 100, and cooperate with each of the fifth diodes D5 to achieve the boost function of the inductor L; however, this embodiment does not limit this aspect.

[0128] In one possible implementation, the boost protection circuit 100 further includes a filter unit.

[0129] The first end of the filter unit is connected to the third end of the switch unit 102, and the second end of the filter unit is connected to the first end of the inductor L.

[0130] For example, see [link to previous article] Figure 4 and Figure 5 The filter unit includes capacitors Ca and Cb connected in parallel, and the first plate of capacitor Ca is connected to the first and second terminals of the switching unit 102 to input the first operating voltage.

[0131] This can improve the stability of circuit 100.

[0132] In one possible implementation, the boost control unit 103 may include at least a processing unit U2 and a third switching transistor Q3.

[0133] Additionally, the boost control unit 103 may also include resistors R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, and R19; capacitors C5, C6, C7, C8, C9, C10, C11, and C12; and diodes D7 and D8. Each capacitor can be used as a filter capacitor, and each resistor can be used as a voltage divider or current limiting resistor. Furthermore, the capacitors and resistors can form an RC network. Diodes D7 and D8 may have unidirectional conduction and / or clamping functions; however, this embodiment does not limit their functionality.

[0134] The specific connection relationships are as follows: Figure 5 The embodiments described herein will not be elaborated upon further.

[0135] The VCC terminal of processing unit U2 is connected to the fourth terminal of switching unit 102, so that switching unit 102 supplies power to processing unit U2. The output terminal of processing unit U2 is connected to the first terminal of third switching transistor Q3, so that processing unit U2 outputs a PWM signal to third switching transistor Q3 to control the third switching transistor Q3 to turn on and off.

[0136] Additionally, the VF terminal of processing unit U2 can also be connected to the output terminal OUT+ of circuit 100. After the output voltage of circuit 100 is divided by resistors R10, R11, and R12 and output to the VF terminal, processing unit U2 can adjust the duty cycle of the PWM signal output to the third switching transistor Q3 according to this output voltage, thereby changing the switching frequency of the third switching transistor Q3 and thus adjusting the boost capability of inductor L. In this way, the voltage level of the output voltage of circuit 100 can be adjusted through processing unit U2.

[0137] The following describes an electronic device including the boost protection circuit provided in this application. The specific implementation process and technical effects are described above and will not be repeated here.

[0138] Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. See also... Figure 6 The electronic device S includes at least the boost protection circuit 100 provided in any of the above embodiments.

[0139] The input terminal of the boost protection circuit 100 is connected to the energy storage device 200, and the output terminal of the boost protection circuit 100 is connected to the external device 300.

[0140] Optionally, the electronic device S may also include an energy storage device 200. The energy storage device 200 is used to provide the aforementioned first operating voltage to the boost protection circuit 100.

[0141] The boost protection circuit 100 is used to output the boosted voltage to the external device 300.

[0142] In addition, the electronic device S may also include any other possible modules or units such as audio input devices, audio output devices, and display devices to achieve the corresponding functions.

[0143] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0144] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A boost protection circuit, characterized by, The circuit comprises a short-circuit protection unit, an inductor, a switch unit and a boost control unit; The first end of the short-circuit protection unit is connected to the positive pole of an energy storage device to input a first working voltage, and the first end of the short-circuit protection unit is also connected to the first end of the inductor, the first end of the switch unit and the second end of the switch unit respectively, and the second end of the short-circuit protection unit is connected to the third end of the switch unit; the short-circuit protection unit is used to be turned off when the circuit is short-circuited to cut off a power loop outputting the first working voltage to an external device, and the short-circuit protection unit is turned on or turned off based on the output voltage of the circuit; The second end of the inductor is connected to the external device and the first end of the boost control unit respectively; The fourth end of the switch unit is connected to the second end of the boost control unit; the switch unit is turned on or turned off under the action of the short-circuit protection unit, and supplies power to the boost control unit when the switch unit is turned on; the boost control unit is used to control the energy storage of the inductor or the discharge to the external device.

2. The boost protection circuit of claim 1, wherein, The short-circuit protection unit comprises an isolation switch and a switch module; The first end of the isolation switch is connected to the first end of the inductor, the second end of the isolation switch is connected to the first end of the switch module, the third end of the isolation switch is used to input the electrical energy output by the inductor, and the fourth end of the isolation switch is connected to the second end of the switch module; the isolation switch is used to convert the first working voltage into a second working voltage and output the second working voltage to the switch module; The third end of the switch module is connected to the third end of the switch unit, and the fourth end of the switch module is used to connect to the negative pole of an energy storage device; the switch module is turned off when the circuit is short-circuited to cut off the power loop.

3. The boost protection circuit of claim 2, wherein, The switch module comprises at least a first diode, a second diode, a first resistor, a second resistor, a third resistor, a fourth resistor and a first switch tube; The first end of the first resistor is connected to the second end of the isolation switch, and the second end of the first resistor is connected to the first pole of the first switch tube, the first end of the second resistor and the negative pole of the first diode respectively; The second pole of the first switch tube is connected to the second end of the second resistor, the negative pole of the first diode and the first end of the third resistor respectively, and the third pole of the first switch tube is connected to the second end of the third resistor, the third end of the switch unit and the first end of the fourth resistor respectively; The negative pole of the second diode is connected to the fourth end of the isolation switch, and the positive pole of the second diode is connected to the second end of the fourth resistor; the second diode is used to be disconnected when the circuit is short-circuited.

4. The boost protection circuit of claim 3, wherein, The first switch tube is an N-channel switch tube; the third resistor is a plurality of resistors connected in parallel.

5. The boost protection circuit of claim 1, wherein, The switch unit comprises at least a third diode, a fourth diode and a second switch tube; The anode of the third diode is connected with the first end of the short-circuit protection unit and the first electrode of the second switch tube respectively, the cathode of the third diode is connected with the second end of the short-circuit protection unit and the anode of the fourth diode respectively, and the cathode of the fourth diode is connected with the second electrode of the second switch tube. The third electrode of the second switch tube is connected with the third end of the short-circuit protection unit, and the first electrode of the second switch tube is grounded; the second switch tube is used for outputting the working voltage to the boost control unit under the action of the short-circuit protection unit.

6. The boost protection circuit of claim 5, wherein, The switch unit further comprises a fifth resistor, a sixth resistor, a first capacitor and a second capacitor. The fifth resistor and the sixth resistor are connected in series between the first end of the short-circuit protection unit and the anode of the third diode. The first capacitor is connected in parallel with the third diode, and the second capacitor is connected between the first electrode of the second switch tube and the anode of the third diode.

7. The boost protection circuit of claim 1, wherein, The boost protection circuit further comprises an anti-backflow unit. The first end of the anti-backflow unit is connected with the second end of the inductor and the first end of the boost control unit respectively, and the second end of the anti-backflow unit is used for connecting the external device.

8. The boost protection circuit of claim 7, wherein, The anti-backflow unit comprises at least one fifth diode. The anode of each fifth diode is connected with the second end of the inductor, and the cathode of each fifth diode is used for connecting the external device.

9. The crowbar circuit of any one of claims 1-8, wherein, The boost protection circuit further comprises a filter unit. The first end of the filter unit is connected with the third end of the switch unit, and the second end of the filter unit is connected with the first end of the inductor.

10. An electronic device, comprising: The boost protection circuit comprises: The boost protection circuit according to any one of claims 1 to 9.

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