Overcurrent protection circuit and electronic device

Abstract

The application discloses an overcurrent protection circuit, and belongs to the technical field of circuits.The overcurrent protection circuit comprises a charging IC, a switch control circuit and a first transistor; a first electrode of the first transistor is connected with the switch control circuit; second electrodes of the first transistor are connected with a first end of a battery and a first end of the charging IC respectively; and a third electrode of the first transistor is connected with a second end of the charging IC; the switch control circuit is used for controlling the first transistor to be turned on when a discharge current of the battery is greater than a first current threshold, so that the first transistor is shunted in parallel with the charging IC, and the first transistor is controlled to be turned off when the discharge current of the battery is less than the first current threshold.

Description

Technical Field

[0001] This application belongs to the field of circuit technology, specifically relating to an overcurrent protection circuit and electronic device. Background Technology

[0002] Charging ICs are an essential component in various terminals. They primarily provide power path management functions, including managing charging and discharging logic, switching between charging and discharging states, managing charging and discharging current, and executing safety protection mechanisms.

[0003] As terminal functions increase and performance improves, system power consumption inevitably increases, especially transient power consumption. The overcurrent capacity of the charging IC is limited, and it can easily exceed the overcurrent threshold, triggering overcurrent protection and causing the system to shut down.

[0004] To improve the overcurrent level inside the charging IC, the charging IC needs to be redesigned, for example, by giving the MOSFETs inside the charging IC a larger area and giving the charging IC a larger heat dissipation pad. However, redesigning the charging IC is time-consuming, labor-intensive, and increases costs. Summary of the Invention

[0005] The purpose of this application is to provide an overcurrent protection circuit and electronic device that can solve the problems in the related art where the overcurrent protection capability of the charging IC is limited, the system is prone to power failure and shutdown, and redesigning the charging IC is time-consuming, labor-intensive, and increases costs.

[0006] In a first aspect, embodiments of this application provide an overcurrent protection circuit, which includes: a charging IC, a switch control circuit, and a first transistor;

[0007] The first terminal of the first transistor is connected to the switch control circuit, the second terminal of the first transistor is connected to the first terminal of the battery and the first terminal of the charging IC, and the third terminal of the first transistor is connected to the second terminal of the charging IC.

[0008] The switch control circuit is used to control the first transistor to turn on when the battery discharge current is greater than a first current threshold, so that the first transistor is connected in parallel with the charging IC to shunt current, and to control the first transistor to turn off when the battery discharge current is less than the first current threshold.

[0009] Secondly, embodiments of this application provide an electronic device that includes the overcurrent protection circuit described in the first aspect.

[0010] In this embodiment, the second terminal of the first transistor is connected to the first terminal of the battery and the first terminal of the charging IC, respectively, and the third terminal of the first transistor is connected to the second terminal of the charging IC, thereby realizing the parallel connection of the first transistor and the charging IC. The first terminal of the first transistor is connected to the switch control circuit. Thus, the switch control circuit can control the first transistor to conduct when the battery discharge current is greater than the first current threshold, so that the first transistor and the charging IC are connected in parallel to shunt current, and to disconnect when the battery discharge current is less than the first current threshold. This increases the discharge capacity while maintaining the original structure and function of the charging IC, and solves the problem of overcurrent protection of the charging IC when the power consumption is high. Moreover, the hardware logic of the overcurrent protection circuit itself can realize the above control logic without software intervention, which can meet the requirements of transient power consumption shunt and has high reliability. Attached Figure Description

[0011] Figure 1 One of the schematic diagrams of an overcurrent protection circuit provided in an embodiment of this application;

[0012] Figure 2 One of the schematic diagrams illustrating the transmission characteristics of an inverting comparator provided in an embodiment of this application;

[0013] Figure 3 A second schematic diagram illustrating the transmission characteristics of an inverting comparator provided in an embodiment of this application;

[0014] Figure 4 This is a second schematic diagram of an overcurrent protection circuit provided in an embodiment of this application. Detailed Implementation

[0015] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0016] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0017] The overcurrent protection circuit and electronic equipment provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0018] In related technologies, a controlled MOSFET is integrated within the charging IC between the battery output terminal and the system power supply terminal. All current from the system power supply terminal must pass through this MOSFET. This MOSFET can be in different states according to different needs, realizing the function of power path management. As terminal functions increase and performance improves, system power consumption will inevitably increase, especially transient power consumption. However, the overcurrent capability of the MOSFET inside the charging IC is limited, and it is easy to exceed the overcurrent threshold of the MOSFET, triggering overcurrent protection and causing the system to shut down.

[0019] To improve the overcurrent level of the MOSFETs inside the charging IC, the charging IC needs to be redesigned, for example, by giving the MOSFETs a larger area and the charging IC a larger heat dissipation pad. However, redesigning the charging IC is time-consuming, labor-intensive, and increases costs.

[0020] Therefore, one embodiment of this application provides an overcurrent protection circuit that can be applied to an electronic device including a battery. The overcurrent protection circuit includes a charging IC, a switching control circuit, and a first transistor. The first terminal of the first transistor is connected to the switching control circuit, the second terminal of the first transistor is connected to both the first terminal of the battery and the first terminal of the charging IC, and the third terminal of the first transistor is connected to the second terminal of the charging IC. That is, the first transistor and the charging IC are connected in parallel. Since the switching control circuit is connected to the first terminal of the first transistor, it can be used to control the first transistor to conduct when the battery discharge current is greater than a first current threshold, so that the first transistor and the charging IC are connected in parallel to shunt current. Conversely, it can control the first transistor to disconnect when the battery discharge current is less than the first current threshold, so that power is supplied to the system load solely through the charging IC.

[0021] In some embodiments of this application, the switch control circuit is also used to control the first transistor to disconnect when the battery is in a charging state, so as not to affect the normal charging control logic of the charging IC.

[0022] In some embodiments of this application, the first electrode of the first transistor is the gate, the second electrode is the source, and the third electrode is the drain. The state of the first transistor, i.e., on or off, can be controlled by controlling the output voltage of the end of the control circuit connected to the first electrode of the first transistor, thereby realizing whether the first transistor needs to shunt current.

[0023] In some embodiments of this application, the charging IC has a second transistor inside, which can specifically be a MOSFET. The current output from the second terminal of the charging IC needs to pass through this MOSFET. In this case, the MOSFET inside the charging IC can be considered to be connected in parallel with the first transistor outside the charging IC.

[0024] In some embodiments of this application, the second terminal of the charging IC is connected to the switch control circuit, and the first terminal of the battery is also connected to the switch control circuit. Thus, the switch control circuit can control the output voltage of the terminal connected to the first electrode of the first transistor by setting electronic devices such as comparators, thereby controlling the state of the first transistor.

[0025] In some other embodiments of this application, the first transistor can be a MOS transistor, such as a PMOS transistor or a NOMS transistor, which can be connected by a substrate grounding method to avoid the situation where the first terminal of the battery and the second terminal of the charging IC are connected due to the body diode.

[0026] Therefore, in this embodiment, the switch control circuit can control the first transistor to conduct when the battery discharge current is greater than the first current threshold, so that the first transistor is connected in parallel with the charging IC to shunt current, and to disconnect when the battery discharge current is less than the first current threshold. This increases the discharge capacity while maintaining the original structure and function of the charging IC, and solves the problem of overcurrent protection of the charging IC when the power consumption is high. Moreover, the hardware logic of the overcurrent protection circuit itself can implement the above control logic without software intervention, which can meet the requirements of transient power consumption shunt and has high reliability.

[0027] In some embodiments of this application, the switch control circuit includes a comparator. The power supply terminal of the comparator is connected to the second terminal of the charging IC, and the ground terminal of the comparator is grounded. That is, the comparator is powered by the charging IC. The first terminal of the battery is connected to the input terminal of the comparator via a resistor, and the output terminal of the comparator is connected to the first terminal of the first transistor. The voltage at the output terminal of the comparator is either the voltage at the second terminal of the charging IC or zero. In other words, the comparator compares the voltages at the two input terminals to output two different voltage values, namely the voltage at the second terminal of the charging IC or zero, thereby controlling the first transistor to be turned on or off.

[0028] Please refer to Figure 1 , Figure 1 This is one of the schematic diagrams of an overcurrent protection circuit provided in an embodiment of this application. For example... Figure 1As shown, the overcurrent protection circuit in this embodiment includes a charging IC 1, a switch control circuit 2, and a first transistor Q1. The switch control circuit includes a comparator 21. The power supply terminal of the comparator 21 is connected to the second terminal of the charging IC 1, the ground terminal of the comparator 21 is grounded, the input terminal of the comparator 21 is connected to the first terminal of the battery via a resistor, and the output terminal of the comparator 21 is connected to the first terminal of the first transistor Q1. Thus, by comparing the voltage at the first terminal of the battery with the reference voltage of the comparator, the comparator 21 can output a corresponding voltage value to control the first transistor Q1 to turn on or off. In some embodiments, exemplarily, comparator 21 is an inverting comparator, the first transistor Q1 is a PMOS transistor, the charging IC 1 internally has a second transistor Q4, which is specifically a MOS transistor, and the switch control circuit 2 further includes a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4. The first input terminal of the inverting comparator is connected to the first terminals of the first resistor R1 and the second resistor R2, respectively. The second terminal of the first resistor R1 is connected to the output terminal of the inverting comparator. The first terminal of the second resistor R2 is connected to the second terminal of the charging IC 1. The second input terminal of the inverting comparator is connected to the first terminals of the third resistor R3 and the fourth resistor R4, respectively. The second terminal of the third resistor R3 is connected to the first terminal of the battery, and the second terminal of the fourth resistor R4 is grounded. Thus, by comparing the voltages at the first and second input terminals through the inverting comparator, different voltage values ​​are output at the output terminal, ultimately controlling the first transistor Q1 to be in different states, i.e., on or off.

[0029] The working principle of the above overcurrent protection circuit is explained in detail below.

[0030] In this embodiment, the inverting comparator, the first resistor R1, and the second resistor R2 constitute an inverting positive feedback hysteresis comparator circuit. Due to the positive feedback, the inverting comparator operates in a saturated output state, that is, the voltage Vo at the output terminal of the inverting comparator is 0V or Vo = VPH. The voltage at the first terminal of the charging IC 1 is Vbat, the voltage at the second terminal of the charging IC 1 is VPH, the first terminal of the inverting comparator is the "+" input terminal, and the second terminal of the inverting comparator is the "-" input terminal.

[0031] Since the second input terminal of the inverting comparator is directly connected to the first terminal of the battery through the voltage divider formed by the third resistor R3 and the fourth resistor R4, the voltage at the second input terminal of the inverting comparator is: Vn = A * Vbat, where,

[0032] Based on the virtual open circuit principle and the superposition principle of comparators, the voltage at the first input terminal of the inverting comparator is:

[0033]

[0034] Since the output voltage of the inverting comparator is Vo = 0V or Vo = VPH, the inverting comparator has two threshold voltages, namely:

[0035] Lower threshold voltage

[0036] Upper threshold voltage

[0037] in,

[0038] Therefore, the inverting comparator has two operating states.

[0039] Status 1:

[0040] When Vn is less than VT-, regardless of whether the current threshold voltage is VT- or VT+, the output voltage Vo of the inverting comparator must be VPH. At this time, the actual threshold is the upper threshold voltage VT+.

[0041] Therefore, as Vn gradually increases, the inverting comparator will not flip when it reaches VT-. Only when Vn gradually increases to VT+ does the inverting comparator flip, and the output voltage Vo becomes 0V. Simultaneously, the actual threshold also jumps from VT+ to VT-. Its transfer characteristics are as follows: Figure 2 As shown, Figure 2 This is one of the schematic diagrams illustrating the transmission characteristics of an inverting comparator provided in an embodiment of this application.

[0042] State Two:

[0043] As Vn decreases, since the actual threshold is VT-, the inverting comparator does not flip when Vn falls past VT+, and still outputs 0V. Only when Vn is less than VT- does the inverting comparator flip, and the output voltage Vo becomes VPH. Simultaneously, the actual threshold of the inverting comparator also changes from VT- to VT+. Its transfer characteristics are as follows: Figure 3 As shown, Figure 3 This is a second schematic diagram illustrating the transmission characteristics of an inverting comparator provided in an embodiment of this application.

[0044] In some embodiments of this application, when the battery discharge current is greater than a first current threshold, the voltage at the output of the inverting comparator is zero to control the first transistor to turn on.

[0045] When the battery discharge current is less than the second current threshold, the voltage at the output of the inverting comparator is equal to the voltage at the second terminal of the charging IC 1, thereby controlling the first transistor to turn off.

[0046] The first current threshold is greater than the second current threshold.

[0047] In some other embodiments of the present application, the resistance values of the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4 are determined according to the set first current threshold and second current threshold.

[0048] In this embodiment, the principle of hysteresis comparison is adopted. When the discharge current of the battery is greater than the first current threshold, the PMOS transistor (i.e., the first transistor Q1) is controlled to conduct, thereby achieving shunt and avoiding the problem of overcurrent protection of the charging IC 1. When the discharge current of the battery gradually decreases from being greater than the first current threshold to being less than the second current threshold, the PMOS transistor (i.e., the first transistor Q1) is controlled to disconnect, so that the shunt through the PMOS transistor (i.e., the first transistor Ql) is no longer carried out. That is, when the current gradually decreases from being greater than the first current threshold to being less than the first current threshold, the original state of the PMOS transistor is not changed, that is, it remains conducting until it decreases to less than the second current threshold and then the PMOS transistor (i.e., the first transistor Q1) is disconnected. Thus, the discharge current is allowed to fluctuate within a certain range, that is, the load is allowed to fluctuate within a certain range, avoiding the problem of frequent jumping of the first transistor Q1 due to load current fluctuations. The first current threshold and the second current threshold can be adjusted by the resistance values of the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4.

[0049] In this embodiment, the battery has two states, namely the charging state and the discharging state. The following will be elaborated in detail respectively.

[0050] During charging:

[0051] Since the current direction is from VPH to Vbat and passes through the second transistor Q4 inside the charging IC 1, the voltage Vbat at the first end of the battery is less than the voltage VPH at the second end of the charging IC 1. In this case, there is: Vn = A * Vbat < Vbat < VT +, and this equation always holds, so the voltage Vo at the output end of the inverting comparator is always VPH. At this time, Vgs of the first transistor Q1 (PMOS transistor) ≥ 0, and the conduction condition Vgs < Vth (Vth is negative) of the first transistor Q1 cannot be satisfied, and the first transistor Q1 is in the off state. At this time, the first transistor Q1 does not function in the charging state. Thus, it will not affect the normal charging control logic.

[0052] During discharging:

[0053] [[ID=第十九]]It is divided into the small - current discharge situation and the large - current discharge situation. The greater the discharge current, the greater Vbat is than VPH. Since the on - resistance of the second transistor Q4 inside the charging IC 1 is known and represented by R, and the current flowing through the second transistor Q4 inside the charging IC 1 is represented by I. Then there is: Vbat - VPH = I * R.

[0054] When discharging at a large current (i.e., when the discharge current is greater than the first current threshold), when Vn is greater than VT+, that is, A*Vbat > VPH, the output voltage Vo of the inverting comparator is 0V. At this time, the first transistor Q1 conducts, thereby achieving shunting for the charging IC 1.

[0055] When the discharge current decreases and becomes a small current discharge (i.e., when the discharge current is less than the second current threshold), when Vn is less than VT-, that is, A*Vbat < B*VPH, the output voltage Vo of the inverting comparator is VPH. At this time, the first transistor Q1 is turned off, and thus no longer shunts the charging IC 1.

[0056] When the discharge current increases again, that is, when the discharge current is greater than the first current threshold again, causing Vn to increase to be greater than VT+, the first transistor Q1 conducts again, and works in such a cycle.

[0057] Thus, by adjusting the resistance values of the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4, the values of A and B can be arbitrarily changed. It should be noted that the values of A and B are both less than 1.

[0058] The expected first current threshold to be set is represented by I2, and the second current threshold is represented by I1. Since the value ranges of VPH and Vbat are related to the battery voltage and are known, then:

[0059] When I = I2, Vbat - VPH = I2*R, and at the same time, it is necessary to satisfy A*Vbat > VPH. Therefore, 1 > A > VPH / (I2*R + VPH). According to the known value range of VPH, the value of A can be determined, and then the resistance values of the third resistor R3 and the fourth resistor R4 can be determined.

[0060] When I = I1, Vbat - VPH = I1*R, and at the same time, it is necessary to satisfy A*Vbat < B*VPH. Therefore, 1 > B > (A*I1*R) / VPH + A. According to the previously determined value ranges of A and VPH, the value of B can be determined, and then the resistance values of the first resistor R1 and the second resistor R2 can be determined.

[0061] Therefore, in this embodiment, by comparing the voltage difference between the first terminal of the battery and the second terminal of the charging IC 1 using comparator 21, the magnitude of the current discharge current can be determined based on the impedance of the second transistor Q4 inside the charging IC 1. This ensures that the switch control circuit 2 only drives the first transistor Q1 to shunt current when the discharge current gradually increases to a value greater than the first current threshold, thus avoiding the overcurrent protection problem of the charging IC 1 and not affecting the original logic of the charging IC 1. Furthermore, this embodiment employs the principle of hysteresis comparison. When the discharge current gradually decreases to a value less than the first current threshold, the original state of the first transistor remains unchanged. Only when the discharge current decreases to a value less than the second current threshold is the state of the first transistor changed, i.e., switched from the on state to the off state. This avoids the problem of frequent switching of the first transistor Q1 due to load current fluctuations. The first and second current thresholds can be adjusted using the resistance values ​​of the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4.

[0062] Please refer to Figure 4 , Figure 4 This is a second schematic diagram of an overcurrent protection circuit provided in an embodiment of this application. Figure 4 As shown, in this embodiment, the comparator 21 is an inverting comparator, the first transistor Q1 is a PMOS transistor, the charging IC 1 internally has a second transistor Q4, which is specifically a MOS transistor. The switch control circuit 2 also includes a fifth resistor R5, a sixth resistor R6, and a seventh resistor R7. The first input terminal of the inverting comparator is connected to the first terminal of the seventh resistor R7 and the first terminal of the charging IC 1, respectively. The second terminal of the seventh resistor R7 is connected to the first terminal of the battery and the first terminal of the fifth resistor R5, respectively. The second input terminal of the inverting comparator is connected to the second terminal of the fifth resistor R5 and the first terminal of the sixth resistor R6, respectively. The second terminal of the sixth resistor R6 is grounded. Thus, by comparing the voltages of the first and second input terminals through the inverting comparator, different voltage values ​​are output at the output terminal, ultimately controlling the first transistor Q1 to be in different states, i.e., on or off.

[0063] In some embodiments of this application, when the discharge current of the battery is greater than a first current threshold, the voltage at the output of the inverting comparator is zero, so as to control the first transistor to turn on.

[0064] When the discharge current of the battery is less than the first current threshold, the voltage at the output of the inverting comparator is equal to the voltage at the second terminal of the charging IC 1, thereby controlling the first transistor to turn off.

[0065] Optionally, the resistance values ​​of the fifth resistor R5 and the sixth resistor R6 are determined according to the set first current threshold.

[0066] In this embodiment, the comparator has only one threshold voltage, which corresponds to the first current threshold. As long as the discharge current of the battery is less than the first current threshold, the first transistor Q1 is controlled to be turned off, and there is no need for the first transistor Q1 to shunt. As long as the discharge current of the battery is greater than the first current threshold, the first transistor Q1 is controlled to be turned on, and shunting is achieved through the first transistor Q1.

[0067] The working principle of the overcurrent protection circuit described above will be introduced in detail below.

[0068] In this embodiment, in order to accurately set the first current threshold, a precision sampling resistor, that is, the seventh resistor R7, can be added. By detecting the voltage across the seventh resistor R7, the specific current I flowing through the seventh resistor R7 can be calculated.

[0069] Specifically, the inverting comparator operates in an open-loop state. The voltage Vo at the output terminal of the inverting comparator is Vo = 0V or Vo = VPH. Among them, the voltage at the first terminal of the battery is Vbat, and the voltage at the second terminal of the charging IC 1 is VPH. The first terminal of the inverting comparator is the \"+\" input terminal, and the second terminal of the inverting comparator is the \"-\" input terminal. It can be obtained that the voltage at the second input terminal of the inverting comparator is: The voltage at the first input terminal of the inverting comparator is: Vp = Vbat + I * R7, where I can be positive or negative, that is, the battery can be in a charging state or a discharging state.

[0070] During charging:

[0071] Since the current direction is from VPH to Vbat, that is, from the second terminal of the charging IC 1 through the second transistor Q4 inside the charging IC 1 to the first terminal of the charging IC 1, then Vp is greater than Vn. At this time, the voltage Vo at the output terminal of the inverting comparator is Vo = VPH, and the Vgs of the first transistor Q1 (PMOS transistor) is ≥ 0, which cannot meet the on-condition Vgs < Vth (Vth is negative) of the first transistor Q1, and the first transistor Q1 is in an off state. At this time, the first transistor Q1 does not work during charging, and thus, it does not affect the normal charging control logic.

[0072] During discharging:

[0073] At this time, it is divided into the small-current discharge situation and the large-current discharge situation.

[0074] When discharging with a small current, that is, when the discharge current is less than the first current threshold, Vp is still greater than Vn. At this time, the voltage Vo at the output terminal of the inverting comparator is Vo = VPH, and the first transistor Q1 is in an off state.

[0075] When discharging a large current, that is, when the discharge current is greater than the first current threshold and Vp < Vn, the voltage Vo at the output terminal of the inverting comparator is 0V. At this time, the first transistor Q1 is turned on, thereby achieving shunting for the charging IC 1. At this time, from Vp < Vn, we get: That is Since the value range of Vbat is related to the battery voltage and is known, by setting the resistance values of the fifth resistor R5 and the sixth resistor R6, the magnitude of the first current threshold can be set. In other words, as long as the magnitude of the first current threshold is set, the resistance values of the fifth resistor R5 and the sixth resistor R6 can be determined.

[0076] In some embodiments, optionally, the resistance value of the fifth resistor R5 can be set to 0 ohm. At this time, as long as the battery is in a discharge state, the first transistor Q1 will be driven to turn on to achieve shunting.

[0077] In summary, in the embodiments of the present application, the second pole of the first transistor is respectively connected to the first end of the battery and the first end of the charging IC, the third pole of the first transistor is connected to the second end of the charging IC, thereby achieving the parallel connection of the first transistor and the charging IC. The first pole of the first transistor is connected to the switch control circuit. Thus, the switch control circuit can control the first transistor to turn on when the discharge current of the battery is greater than the first current threshold, so that the first transistor is connected in parallel with the charging IC for shunting, and turn off when the discharge current of the battery is less than the first current threshold. Thus, on the basis of maintaining the original structure and function of the charging IC, the discharge capacity is increased, the problem of overcurrent protection of the charging IC caused by large-load power consumption is solved, and the above control logic can be realized by the hardware logic of the above overcurrent protection circuit itself without software participation, which can meet the requirements of transient power consumption shunting and has high reliability. In addition, since the overcurrent protection problem occurs in the battery discharge stage, the first transistor and the switch control circuit added outside the charging IC only intervene in the control in the discharge stage and do not affect the normal charging control logic.

[0078] Another embodiment of the present application also provides an electronic device, which includes the overcurrent protection circuit described in any of the above embodiments and can achieve the same technical effects. To avoid repetition, it will not be elaborated here.

[0079] The electronic device in this application embodiment can be a terminal, or it can be any other device besides a terminal. For example, the electronic device can be a mobile phone, tablet computer, laptop computer, handheld computer, in-vehicle electronic device, mobile internet device (MID), augmented reality (AR) / virtual reality (VR) device, robot, wearable device, ultra-mobile personal computer (UMPC), netbook, or personal digital assistant (PDA), etc. It can also be a server, network attached storage (NAS), personal computer (PC), television (TV), ATM, or self-service machine, etc. This application embodiment does not make specific limitations.

[0080] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0081] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. An overcurrent protection circuit, characterized in that, include: Charging IC, switch control circuit, and first transistor; The first terminal of the first transistor is connected to the switch control circuit, the second terminal of the first transistor is connected to the first terminal of the battery and the first terminal of the charging IC, and the third terminal of the first transistor is connected to the second terminal of the charging IC. The switch control circuit is used to control the first transistor to turn on when the discharge current of the battery is greater than the first current threshold, so that the first transistor is connected in parallel with the charging IC to shunt current, and to control the first transistor to turn off when the discharge current of the battery is less than the first current threshold. The switch control circuit includes a comparator, the power supply terminal of which is connected to the second terminal of the charging IC, the ground terminal of which is grounded, the first terminal of the battery being connected to the input terminal of the comparator via a resistor, and the output terminal of the comparator being connected to the first terminal of the first transistor.

2. The overcurrent protection circuit according to claim 1, characterized in that, The comparator is an inverting comparator, the first transistor is a PMOS transistor, and the switch control circuit further includes a first resistor, a second resistor, a third resistor, and a fourth resistor. The first input terminal of the inverting comparator is connected to the first terminal of the first resistor and the first terminal of the second resistor, respectively. The second terminal of the first resistor is connected to the output terminal of the inverting comparator, the second terminal of the second resistor is connected to the second terminal of the charging IC, the second input terminal of the inverting comparator is connected to the first terminal of the third resistor and the first terminal of the fourth resistor, the second terminal of the third resistor is connected to the first terminal of the battery, and the second terminal of the fourth resistor is grounded.

3. The overcurrent protection circuit according to claim 2, characterized in that, When the discharge current of the battery is greater than the first current threshold, the voltage at the output of the inverting comparator is zero, thereby controlling the first transistor to turn on. When the discharge current of the battery is less than the second current threshold, the voltage at the output of the inverting comparator is equal to the voltage at the second terminal of the charging IC, thereby controlling the first transistor to turn off. Wherein, the first current threshold is greater than the second current threshold.

4. The overcurrent protection circuit according to claim 3, characterized in that, The resistance values ​​of the first resistor, the second resistor, the third resistor, and the fourth resistor are determined according to the set first current threshold and the second current threshold.

5. The overcurrent protection circuit according to claim 1, characterized in that, The comparator is an inverting comparator, the first transistor is a PMOS transistor, and the switch control circuit further includes a fifth resistor, a sixth resistor, and a seventh resistor. The first input terminal of the inverting comparator is connected to the first terminal of the seventh resistor and the first terminal of the charging IC, respectively. The second terminal of the seventh resistor is connected to the first terminal of the battery and the first terminal of the fifth resistor, respectively. The second input terminal of the inverting comparator is connected to the second terminal of the fifth resistor and the first terminal of the sixth resistor, respectively. The second terminal of the sixth resistor is grounded.

6. The overcurrent protection circuit according to claim 5, characterized in that, When the discharge current of the battery is greater than the first current threshold, the voltage at the output of the inverting comparator is zero, thereby controlling the first transistor to turn on. When the discharge current of the battery is less than the first current threshold, the voltage at the output of the inverting comparator is equal to the voltage at the second terminal of the charging IC, thereby controlling the first transistor to turn off.

7. The overcurrent protection circuit according to claim 5, characterized in that, The resistance values ​​of the fifth resistor and the sixth resistor are determined according to the set first current threshold.

8. The overcurrent protection circuit according to claim 1, characterized in that, The switch control circuit is also used to control the first transistor to disconnect when the battery is in a charging state.

9. An electronic device, characterized in that, Includes the overcurrent protection circuit as described in any one of claims 1-8.

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