Control method of switching power supply system, switching power supply system and device

Abstract

The application discloses a control method of a switching power supply system, the switching power supply system and a device, and belongs to the technical field of switching power supplies. The control method of the switching power supply system comprises the following steps: detecting an input voltage, an output voltage, a current flowing through a first main switch tube and a current flowing through a fourth main switch tube of the switching power supply system; in response to a multiple relationship between the input voltage and the output voltage and the current flowing through a target main switch tube satisfying a preset starting condition, increasing a gate voltage of a target auxiliary switch tube connected in parallel with the target main switch tube, so that the target auxiliary switch tube works in a linear region; and in response to a decreasing slope of the current flowing through the target main switch tube being greater than a first slope threshold, decreasing a slope of the increase of the gate voltage of the target auxiliary switch tube until the target auxiliary switch tube is completely opened. The control method of the switching power supply system disclosed by the application realizes the power conversion effect of high efficiency, low heat generation and high reliability under large current.

Description

Technical Field

[0001] This application belongs to the field of switching power supply technology, and in particular relates to a control method, switching power supply system and device for a switching power supply system. Background Technology

[0002] Four-transistor buck-boost switching power supply circuits are widely used in consumer electronics products because they can achieve boost, buck, and buck-boost operating modes. Currently, to improve the efficiency of this circuit, methods such as optimizing the switching transistor overlap timing, introducing a shoot-through mode, or directly reducing the on-resistance of the switching transistors are commonly used. However, under high voltage and high current conditions, conventional timing optimization yields minimal results; increasing the chip area to reduce on-resistance significantly increases chip cost and package size, making it difficult to achieve a balance between cost and performance. Furthermore, the sudden turn-on of parallel switching transistors under high current can easily induce current oscillations, leading to decreased system stability. Therefore, how to ensure efficient and stable operation of the system under high voltage and high current without significantly increasing costs has become a critical technical problem that urgently needs to be solved. Summary of the Invention

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a control method, a switching power supply system, and a device for a switching power supply system, achieving high efficiency, low heat generation, and high reliability power conversion under high current, and ensuring the overall efficiency performance of the system across the entire load range.

[0004] In a first aspect, this application provides a control method for a switching power supply system, the switching power supply system including a first main switch transistor, a fourth main switch transistor, a first auxiliary switch transistor connected in parallel across the first main switch transistor, and a second auxiliary switch transistor connected in parallel across the fourth main switch transistor; the method includes: The input voltage, output voltage, current flowing through the first main switch transistor, and current flowing through the fourth main switch transistor of the switching power supply system are detected. In response to the multiple relationship between the input voltage and the output voltage, and the fact that the current flowing through the target main switch meets the preset turn-on condition, the gate voltage of the target auxiliary switch connected in parallel with the target main switch is increased, so that the target auxiliary switch operates in the linear region, thereby increasing the current flowing through the target auxiliary switch and decreasing the current flowing through the target main switch. In response to the current flowing through the target main switch decreasing at a rate greater than a first rate threshold, the gate voltage of the target auxiliary switch is controlled to decrease at a rate until the target auxiliary switch is fully turned on.

[0005] According to the control method of the switching power supply system provided in the embodiments of this application, the sudden change process of current is transformed into a slope transition with a fixed slope through the controlled turn-on of the linear region and the slope feedback adjustment of the closed loop. Without significantly increasing the chip area and peripheral circuits, it effectively solves the problems of difficulty in improving efficiency under high current conditions and easy oscillation when parallel turn-on, and achieves high efficiency, low heat generation and high reliability power conversion effect under high current. Moreover, since the parallel auxiliary tube is only triggered to turn on under the high current condition of the main tube and does not participate in the operation under light or medium load, it further ensures the overall efficiency performance of the system across the entire load range.

[0006] One embodiment of the control method for a switching power supply system of this application, wherein when the switching power supply system is in a charging state, the preset start-up conditions include: The input voltage is greater than the output voltage by a first multiple, and the current flowing through the fourth main switch is greater than the first current threshold; the target main switch is the fourth main switch, and the target auxiliary switch is the second auxiliary switch; The input voltage is less than the second multiple of the output voltage, and the current flowing through the first main switch is greater than the second current threshold; the target main switch is the first main switch, the target auxiliary switch is the first auxiliary switch, and the second multiple is less than the first multiple.

[0007] One embodiment of the control method for a switching power supply system of this application includes, when the switching power supply system is in a discharging state, the preset start-up conditions include: The output voltage is greater than the input voltage by a first multiple, and the current flowing through the first main switch is greater than the third current threshold; the target main switch is the first main switch, and the target auxiliary switch is the first auxiliary switch; The output voltage is less than the second multiple of the input voltage, and the current flowing through the fourth main switch is greater than the fourth current threshold; the target main switch is the fourth main switch, the target auxiliary switch is the second auxiliary switch, and the second multiple is less than the first multiple.

[0008] A control method for a switching power supply system according to an embodiment of this application, determining that the rate of decrease of the current flowing through the target main switch is greater than a first rate threshold, includes: The current flowing through the target main switch is converted into a first voltage signal, and a ramp voltage signal with a fixed slope is generated. When the first voltage signal is less than the ramp voltage signal, it is determined that the rate of decrease of the current flowing through the target main switch is greater than the first slope threshold.

[0009] Secondly, this application provides a switching power supply system, comprising: The main switch module includes a first main switch, a second main switch, a third main switch, and a fourth main switch. The auxiliary switching module includes a first auxiliary switching transistor connected in parallel across the first main switching transistor and a second auxiliary switching transistor connected in parallel across the fourth main switching transistor. The current detection circuit module includes a first current detection circuit and a second current detection circuit, which are used to detect the current of the first main switch and the current of the fourth main switch, respectively. A mode control circuit, connected to the current detection circuit module, is used to generate a first enable signal and a second enable signal based on the input voltage, the output voltage, the current of the first main switch and the current of the fourth main switch. An auxiliary drive circuit, connected to the mode control circuit and the current detection circuit module, includes a third drive circuit and a fourth drive circuit. The third drive circuit is used to drive the first auxiliary switch in response to the first enable signal, and the fourth drive circuit is used to drive the second auxiliary switch in response to the second enable signal. The third driving circuit and the fourth driving circuit respectively include a current slope judgment circuit and a charge pump circuit; The current slope judgment circuit is used to detect the current reduction slope of the corresponding target main switch, and outputs a feedback control signal when the current reduction slope is greater than a first slope threshold; the charge pump circuit is used to control the rise rate of the gate voltage of the corresponding target auxiliary switch according to the feedback control signal.

[0010] According to the switching power supply system provided in the embodiments of this application, the integrated current detection circuit, mode control circuit, and auxiliary drive circuit including current slope judgment circuit and charge pump circuit can realize dynamic detection and shunt control of the main power supply current without the need for input voltage sampling pin. The current slope judgment circuit monitors the reduction slope of the target main power supply current in real time, and accurately adjusts the gate voltage rise rate of the charge pump output through feedback signal when the limit is exceeded, fundamentally avoiding current oscillation caused by hard turn-on of the auxiliary tube. With the precise matching of the mode control circuit under buck-boost and charge-discharge conditions, the system can accurately trigger the parallel steady state of the main switch and the auxiliary switch, and achieve a significant reduction in conduction loss with a simplified peripheral circuit, thereby significantly improving the energy conversion efficiency over a wide current and voltage range while ensuring system stability.

[0011] One embodiment of the switching power supply system of this application, One end of the first auxiliary switch is connected to the input voltage terminal, and the other end is connected to the first switch node; One end of the second auxiliary switch is connected to the output voltage terminal, and the other end is connected to the second switch node; The current detection circuit module includes: The first sampling switch and the second sampling switch have their drains connected to the input voltage terminal, their sources connected to the first switching node, and their gates used to receive drive signals. The first resistor is connected between the input voltage terminal and one input terminal of the error amplifier; The second resistor is connected between the input voltage terminal and the other input terminal of the error amplifier; An adjustment switch is provided, the gate of which is connected to the output of the error amplifier, and the drain of which is connected to the common node of the second resistor and another input of the error amplifier. The first capacitor has one end connected to the source of the regulating switch tube via a first switch, and the other end grounded. The first switch is connected in parallel with the first capacitor.

[0012] In one embodiment of the switching power supply system of this application, the current slope determination circuit includes: A current source, wherein the power supply terminal of the current source is connected to the input voltage terminal; The second capacitor is charged by the current source through the second switch to generate a second voltage signal that varies with a fixed slope on the second capacitor. The second switch operates synchronously with the first switch and the target auxiliary switch. A comparator, one input of which is used to receive the second voltage signal, and the other input of which is used to receive the first voltage signal, and the output of which is connected to the charge pump circuit; when the first voltage signal is less than the second voltage signal, the comparator outputs the feedback control signal.

[0013] Thirdly, this application provides a control device for a switching power supply system, the switching power supply system including a first main switch transistor, a fourth main switch transistor, a first auxiliary switch transistor connected in parallel across the first main switch transistor, and a second auxiliary switch transistor connected in parallel across the fourth main switch transistor; the device includes: The first processing module is used to detect the input voltage, output voltage, current flowing through the first main switch transistor, and current flowing through the fourth main switch transistor of the switching power supply system. The second processing module is used to respond to the multiple relationship between the input voltage and the output voltage, and the fact that the current flowing through the target main switch meets the preset turn-on conditions, to control the gate voltage of the target auxiliary switch connected in parallel with the target main switch to increase, so that the target auxiliary switch operates in the linear region, thereby increasing the current flowing through the target auxiliary switch and decreasing the current flowing through the target main switch. The third processing module is used to control the rate of increase of the gate voltage of the target auxiliary switch to decrease in response to the current decrease slope of the target main switch being greater than a first slope threshold, until the target auxiliary switch is fully turned on.

[0014] According to the control device of the switching power supply system provided in the embodiments of this application, the sudden change process of current is transformed into a slope transition with a fixed slope through the controlled opening of the linear region and the slope feedback adjustment of the closed loop. Without significantly increasing the chip area and peripheral circuits, it effectively solves the problems of difficulty in improving efficiency under high current conditions and easy oscillation when parallel opening is activated, and achieves high efficiency, low heat generation and high reliability power conversion effect under high current. Moreover, since the parallel auxiliary tube is only triggered to open under the high current condition of the main tube and does not participate in the operation under light or medium load, it further ensures the overall efficiency performance of the system across the entire load range.

[0015] Fourthly, this application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the control method of the switching power supply system as described in the first aspect above.

[0016] Fifthly, this application provides a chip including a processor and a communication interface, the communication interface being coupled to the processor, the processor being used to run programs or instructions to implement the control method of the switching power supply system as described in the first aspect.

[0017] The above-described one or more technical solutions in the embodiments of this application have at least one of the following technical effects: By controlling the turn-on of the linear region and adjusting the slope feedback in the closed loop, the sudden change in current is transformed into a gradual transition with a fixed slope. Without significantly increasing the chip area and peripheral circuitry, this effectively solves the problems of difficulty in improving efficiency under high current conditions and easy oscillation when the parallel tube is turned on. This achieves high efficiency, low heat generation, and high reliability power conversion under high current conditions. Furthermore, since the parallel auxiliary tube is only triggered to turn on under high current conditions in the main tube and does not participate in operation under light or medium loads, the overall efficiency performance of the system is further guaranteed across the entire load range.

[0018] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0019] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of a four-switch buck-boost switching power converter. Figure 2 This is one of the structural schematic diagrams of the switching power supply system provided in the embodiments of this application; Figure 3 This is one of the flowcharts illustrating the control method of the switching power supply system provided in the embodiments of this application; Figure 4 This is a second schematic flowchart of the control method for the switching power supply system provided in the embodiments of this application; Figure 5 This is one of the schematic diagrams of current change in the control method of the switching power supply system provided in the embodiments of this application; Figure 6 This is the second schematic diagram of current change in the control method of the switching power supply system provided in the embodiments of this application; Figure 7 This is a second schematic diagram of the switching power supply system provided in the embodiments of this application; Figure 8 This is the third schematic diagram of the switching power supply system provided in the embodiments of this application; Figure 9 This is the fourth schematic diagram of the switching power supply system provided in the embodiments of this application; Figure 10 This is the fifth schematic diagram of the switching power supply system provided in the embodiments of this application; Figure 11 This is the third flowchart illustrating the control method of the switching power supply system provided in the embodiments of this application; Figure 12 This is a schematic diagram of the structure of the control device of the switching power supply system provided in the embodiments of this application; Figure 13 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application.

[0020] Figure label: M1, First main switch; M2, Second main switch; M3, Third main switch; M4, Fourth main switch; M5, First auxiliary switch; M6, Second auxiliary switch; VBUS, Input voltage terminal; SW1, First switching node; SW2, Second switching node; VBAT, Output voltage terminal; L, Inductor; M1_N, First sampling switch; M1_1, Second sampling switch; EA, Error amplifier; R1, First resistor; R2, Second resistor; MP, Adjustment switch; Cs, First capacitor; I1, Current source; Cslope, Second capacitor; S1, First switch; S2, Second switch; COMP, Comparator; 110. First current detection circuit; 120. Second current detection circuit; 130. Mode control circuit; 140. Third drive circuit; 150. Fourth drive circuit; 160. First drive circuit; 170. Second drive circuit; 180. Current slope judgment circuit; 190. Charge pump circuit; Detailed Implementation 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.

[0021] 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.

[0022] The control method, control device, electronic device, and readable storage medium of the switching power supply system provided in this application will be described in detail below with reference to the accompanying drawings and through specific embodiments and application scenarios.

[0023] The control method of the switching power supply system can be applied to the terminal, and can be executed by the hardware or software in the terminal.

[0024] The control method for a switching power supply system provided in this application embodiment can be executed by an electronic device or a functional module or entity in an electronic device that can implement the control method for the switching power supply system. The electronic devices mentioned in this application embodiment include, but are not limited to, mobile phones, tablets, computers, cameras, and wearable devices. The control method for a switching power supply system provided in this application embodiment will be described below using an electronic device as the execution subject as an example.

[0025] It should be noted that the switching power supply system of this application is based on, for example... Figure 1 The illustrated four-switch buck-boost converter topology includes an input voltage terminal VBUS, an output voltage terminal VBAT, and an energy storage inductor L connected between the first switching node SW1 and the second switching node SW2. The first main switch M1 is connected between VBUS and SW1, the second main switch M2 is connected between SW1 and ground, the third main switch M3 is connected between SW2 and ground, and the fourth main switch M4 is connected between VBAT and SW2. Figure 2 The control architecture of this application is illustrated. Based on the main topology, a first auxiliary switch M5 connected in parallel across the first main switch M1 and a second auxiliary switch M6 connected in parallel across the fourth main switch M4 are added to cope with active current shunting under high current conditions.

[0026] like Figure 11 As shown, the control method of the switching power supply system includes steps S1, S2 and S3.

[0027] The switching power supply system includes a first main switch transistor, a fourth main switch transistor, a first auxiliary switch transistor connected in parallel across the first main switch transistor, and a second auxiliary switch transistor connected in parallel across the fourth main switch transistor.

[0028] Step S1: Detect the input voltage, output voltage, current flowing through the first main switch transistor, and current flowing through the fourth main switch transistor of the switching power supply system; In this step, the input voltage of the switching power supply system is the voltage introduced from the input terminal of the switching power supply system, which is usually connected to an external power supply or adapter.

[0029] The output voltage is the voltage at the system output terminal, which is usually connected to a battery load.

[0030] Step S2: In response to the multiple relationship between the input voltage and the output voltage, and the fact that the current flowing through the target main switch meets the preset turn-on condition, the gate voltage of the target auxiliary switch connected in parallel with the target main switch is increased, so that the target auxiliary switch operates in the linear region, thereby increasing the current flowing through the target auxiliary switch and decreasing the current flowing through the target main switch. In this step, the preset start-up conditions are different when the switching power supply system is in different states (charging state / discharging state). The corresponding preset start-up conditions can be determined based on the current state of the switching power supply system, and it can be judged whether each parameter meets the preset start-up conditions.

[0031] The linear region is the region in which the gate voltage of a metal-oxide-semiconductor field-effect transistor (MOSFET) is greater than the turn-on threshold voltage. It is a transitional operating range before it has entered the fully saturated conduction region.

[0032] Based on the physical characteristics of a MOSFET, the current flowing through the switching transistor in the linear region... With gate voltage They exhibit an approximately linear relationship and satisfy the formula ,in For process parameters, This is the threshold voltage.

[0033] Step S3: In response to the decrease in the slope of the current flowing through the target main switch being greater than the first slope threshold, the increase in the gate voltage of the target auxiliary switch is controlled to decrease until the target auxiliary switch is fully turned on.

[0034] In this step, the first slope threshold is used to limit the main current from being drawn away too quickly, which could cause voltage spikes or electromagnetic oscillations.

[0035] like Figure 2 As shown, the system monitors the input voltage VBUS, output voltage VBAT, current I_M1 flowing through the first main switch M1, and current I_M4 flowing through the fourth main switch M4 in real time.

[0036] The mode control circuit can dynamically determine the target main switch and its parallel target auxiliary switch based on the ratio of VBUS to VBAT and whether the current flowing through the target main switch meets the preset turn-on conditions, and control the target auxiliary switch to turn on.

[0037] After the target transistor is identified, the system controls the gate voltage of the target auxiliary switch, which is connected in parallel with the target main switch, to increase slowly. At this point, the target auxiliary switch will first enter the linear region. According to the linear region formula, the current flowing through the target auxiliary switch will gradually increase as the gate voltage slowly rises, while the current originally flowing through the target main switch will decrease steadily accordingly.

[0038] During this current shunting process, the current slope judgment circuit monitors the rate of decrease of the target main switch current in real time. When the current decrease slope is detected to be greater than the first slope threshold, it indicates that the current shunting speed is too fast. The system will immediately output a feedback control signal to reduce the rate of rise of the charge pump output voltage, thereby slowing down the turn-on process of the target auxiliary switch until the target auxiliary switch is fully turned on.

[0039] like Figure 6 The current waveform shown demonstrates a smooth current shunting process during the control circuit's turn-on, where the current changes gradually, avoiding issues such as... Figure 5 The diagram shows the current surge caused by rapid changes in current during the uncontrolled circuit turn-on process.

[0040] In this application, by responding to the multiple relationship between the input voltage and the output voltage, and by ensuring that the current flowing through the target main switch meets the preset turn-on conditions, a specific main switch (M1 or M4) currently in an overload state can be accurately located under high current conditions, and the corresponding auxiliary switch (M5 or M6) connected in parallel with it can be turned on immediately. This eliminates the need to increase the chip area of ​​the main switch to reduce the on-resistance; instead, it effectively reduces the on-resistance by dynamically introducing an auxiliary current shunt path. Without significantly increasing chip cost and package size, this effectively solves the problem of severe heat generation and a sharp drop in efficiency of a single main switch under high current conditions.

[0041] This application addresses the potential drawback of related technologies where sudden switching of the auxiliary transistor can easily cause current oscillations and reduce system stability by employing dynamic linear region control. By controlling the gate voltage of the target auxiliary transistor to increase slowly, it is made to operate in the linear region initially, thereby gradually increasing the current flowing through the auxiliary transistor and gradually decreasing the current of the main switch.

[0042] In this application, in response to the decreasing slope of the current flowing through the target main switch being greater than a first slope threshold, the increasing slope of the gate voltage of the target auxiliary switch is actively controlled to decrease until the auxiliary switch is fully turned on. This negative feedback regulation ensures that the current switching during the auxiliary switch turn-on process always follows a smooth transition with a fixed slope, avoiding electromagnetic interference (EMI) and voltage spikes caused by sudden current changes.

[0043] According to the control method of the switching power supply system provided in the embodiments of this application, the sudden change process of current is transformed into a slope transition with a fixed slope through the controlled turn-on of the linear region and the slope feedback adjustment of the closed loop. Without significantly increasing the chip area and peripheral circuits, it effectively solves the problems of difficulty in improving efficiency under high current conditions and easy oscillation when parallel turn-on, and achieves high efficiency, low heat generation and high reliability power conversion effect under high current. Moreover, since the parallel auxiliary tube is only triggered to turn on under the high current condition of the main tube and does not participate in the operation under light or medium load, it further ensures the overall efficiency performance of the system across the entire load range.

[0044] In some embodiments, when the switching power supply system is in a charging state, the preset start-up conditions include: The input voltage is greater than the first multiple of the output voltage, and the current flowing through the fourth main switch is greater than the first current threshold; the target main switch is the fourth main switch, and the target auxiliary switch is the second auxiliary switch; The input voltage is less than the second multiple of the output voltage, and the current flowing through the first main switch is greater than the second current threshold; the target main switch is the first main switch, the target auxiliary switch is the first auxiliary switch, and the second multiple is less than the first multiple.

[0045] In some embodiments, when the switching power supply system is in a discharging state, the preset start-up conditions include: The output voltage is greater than the input voltage by a first multiple, and the current flowing through the first main switch is greater than the third current threshold; the target main switch is the first main switch, and the target auxiliary switch is the first auxiliary switch; The output voltage is less than the second multiple of the input voltage, and the current flowing through the fourth main switch is greater than the fourth current threshold; the target main switch is the fourth main switch, the target auxiliary switch is the second auxiliary switch, and the second multiple is less than the first multiple.

[0046] In this embodiment, the charging state refers to the process by which the system supplies power from the input voltage terminal VBUS to the output voltage terminal VBAT.

[0047] The discharge state refers to the process by which the system feeds back energy from the output voltage terminal VBAT to the input voltage terminal VBUS.

[0048] The first and second multiples can be set to 1.1 times and 0.9 times respectively to define the working boundaries of buck and boost voltage, or they can be other values, which will not be elaborated here.

[0049] The first current threshold and the fourth current threshold are current judgment thresholds for different operating modes and different target mains, respectively, to avoid accidental current shunting under light load.

[0050] like Figure 3As shown, when the system is in charging mode, if VBUS is detected to be greater than 1.1 times VBAT, the system is in buck mode. In this mode, the target main switch is the fourth main switch M4. When the current flowing through M4 exceeds the first current threshold, the second auxiliary switch M6 is turned on to shunt the current. If VBUS is less than 0.9 times VBAT, the system is in boost mode. In this mode, the target main switch is the first main switch M1. When the current flowing through M1 exceeds the second current threshold, the first auxiliary switch M5 is turned on.

[0051] like Figure 4 As shown, when the system is in a discharging state, the decision logic is symmetrical to that in a charging state. If the output voltage VBAT is greater than 1.1 times the input voltage VBUS, the target main switch is M1 and the target auxiliary switch is M5; if VBAT is less than 0.9 times VBUS, the target main switch is M4 and the target auxiliary switch is M6.

[0052] According to the control method of the switching power supply system provided in the embodiments of this application, by using independent judgment logic in both charging and discharging states, combined with specific voltage multiples and current thresholds, the buck-boost power supply can accurately and intelligently identify the heavy-load main tube and accurately activate the parallel auxiliary tube in both bidirectional energy flow, ensuring shunt protection under all operating conditions.

[0053] In some embodiments, determining that the rate of decrease in the current flowing through the target main switch is greater than a first slope threshold may include: The current flowing through the target main switch is converted into a first voltage signal, and a ramp voltage signal with a fixed slope is generated. When the first voltage signal is less than the ramp voltage signal, it is determined that the rate of decrease of the current flowing through the target main switch is greater than the first slope threshold.

[0054] In this embodiment, the first voltage signal Vs is the voltage value stored on the first capacitor Cs after the current sensing circuit converts the real-time current of the main switch transistor into a proportional value, representing the magnitude of the real-time current of the main switch transistor.

[0055] The slope voltage signal Vslope is a voltage reference signal that grows linearly with time, generated by charging a capacitor with a constant current source.

[0056] like Figure 8 As shown, the current sensing circuit proportionally converts the current flowing through the target main switch and charges the first capacitor Cs, thereby forming the first voltage signal Vs. The current source I1 charges the second capacitor Cslope through the second switch S2. Due to the constant current charging characteristic, a second voltage signal Vslope is generated across the second capacitor Cslope, rising at a fixed slope.

[0057] The first voltage signal Vs and the second voltage signal Vslope are respectively input to two input terminals of the comparator COMP. For example, Vslope may be connected to the non-inverting input terminal of the comparator, and Vs may be connected to the inverting input terminal of the comparator.

[0058] When the current of the main switching transistor is drawn away too fast during the current sharing process, the first voltage signal Vs drops sharply. When the falling speed of Vs exceeds the rising speed of Vslope with a fixed slope, that is, Vs < Vslope, the state of the comparator COMP flips and outputs a feedback control signal, which directly acts on the charge pump circuit to reduce the rising rate of the gate voltage of the auxiliary transistor.

[0059] The embodiments of the present application further provide a switching power supply system.

[0060] As shown in Figure 2 the figure, the switching power supply system includes: a main switching transistor module, an auxiliary switching transistor module, a current detection circuit module, a mode control circuit 130, and an auxiliary drive circuit.

[0061] In this embodiment, the main switching transistor module includes a first main switching transistor M1, a second main switching transistor M2, a third main switching transistor M3, and a fourth main switching transistor M4.

[0062] The auxiliary switching transistor module includes a first auxiliary switching transistor M5 connected in parallel across the first main switching transistor M1, and a second auxiliary switching transistor M6 connected in parallel across the fourth main switching transistor M4.

[0063] The current detection circuit module includes a first current detection circuit 110 and a second current detection circuit 120, which are respectively configured to detect the current of the first main switching transistor M1 and the current of the fourth main switching transistor M4.

[0064] The mode control circuit 130 is connected to the current detection circuit module, and is configured to generate a first enable signal EN1 and a second enable signal EN2 according to an input voltage, an output voltage, the current of the first main switching transistor M1, and the current of the fourth main switching transistor M4.

[0065] The auxiliary drive circuit is connected to the mode control circuit 130 and the current detection circuit module, and includes a third drive circuit 140 and a fourth drive circuit 150. The third drive circuit 140 is configured to drive the first auxiliary switching transistor M5 in response to the first enable signal EN1, and the fourth drive circuit 150 is configured to drive the second auxiliary switching transistor M6 in response to the second enable signal EN2.

[0066] The third drive circuit 140 and the fourth drive circuit 150 each include a current slope judgment circuit 180 and a charge pump circuit 190.

[0067] The current slope judgment circuit 180 is used to detect the current reduction slope of the corresponding target main switch, and outputs a feedback control signal when the current reduction slope is greater than the first slope threshold; the charge pump circuit 190 is used to control the rise rate of the gate voltage DRV_HS1 or DRV_HS2 of the corresponding target auxiliary switch according to the feedback control signal.

[0068] The charge pump circuit 190 integrated within the auxiliary drive circuits (third drive circuit 140 and fourth drive circuit 150) may, in some embodiments, include an oscillator, a switched capacitor network, and a level shifting module.

[0069] During the turn-on process of the target auxiliary switch, the internal oscillator of the charge pump circuit 190 generates a clock signal of a fixed frequency, driving the capacitor network to continuously pump up the charge, and forming a slowly rising gate drive voltage at the output terminal DRV_HS1 or DRV_HS2. The feedback control signal DRV_HS1_CTRL (or DRV_HS2_CTRL) is directly coupled to the frequency control terminal of the internal oscillator of the charge pump or the bias control terminal of the charging current.

[0070] When the feedback signal is valid (i.e., the slope of the main current change is detected to exceed the limit), this feedback signal, through internal logic, reduces the oscillator's clock frequency or decreases the charging current of the internal switch of the charge pump. The reduced clock frequency or charging current leads to a decrease in the amount of charge accumulated in the internal capacitor of the charge pump per unit time, thus slowing down the rate (i.e., the slope) of voltage increase at the output terminal DRV_HS1 (or DRV_HS2). This closed-loop slope control mechanism continues until the target auxiliary switch is fully turned on and enters a steady state. At this point, the feedback signal is released, and the charge pump resumes its normal rise rate. When the target auxiliary switch is fully turned on, it enters the saturation region, and its on-resistance drops to a minimum. At this time, the target auxiliary switch and the target main switch operate in parallel, and the equivalent on-resistance is the parallel value of the two, thereby achieving low-loss conduction under high current.

[0071] In this application, the aforementioned switching power supply system integrates signal sampling, logic decision-making, current shunt driving, and closed-loop feedback into a single unit. This switching power supply system eliminates the need for additional pins for sampling the input voltage, and avoids reliance on complex external multipliers or compensation circuits. It achieves accurate detection and dynamic current shunt of the main power supply overcurrent state solely through its internally integrated current detection module, mode control circuit 130, and auxiliary drive circuit. This results in significant advantages such as simple peripheral circuitry, high integration, and low system cost.

[0072] The switching power supply system of this application embodiment incorporates a current slope judgment circuit 180 and a charge pump circuit 190 within its auxiliary drive circuit. The current slope judgment circuit 180 monitors the dynamic decrease of the current in the corresponding target main switch in real time, and directly outputs a feedback signal to the charge pump circuit 190 when the current reduction slope exceeds the limit. The charge pump circuit 190 then precisely controls the rise rate of the gate voltage of the target auxiliary switch based on this signal. This hardware-level closed-loop negative feedback mechanism strictly locks the turn-on process of the auxiliary switch into a controlled state, fundamentally avoiding current surges and electromagnetic oscillations caused by the instantaneous hard turn-on of the auxiliary switch, thus ensuring the system's operational stability under high current conditions.

[0073] This application employs independent third drive circuit 140 and fourth drive circuit 150 to control the first auxiliary switch M5 and the second auxiliary switch M6 respectively. Whether in charging or discharging state, and in boost or buck mode, the system can perform rapid and accurate current shunting based on the enable signals EN1 and EN2 output by the mode control circuit 130. This ensures comprehensive current shunting protection during bidirectional energy flow in both boost and buck modes, and significantly reduces the equivalent on-resistance of the main switch by dynamically sharing the current. Thus, with minimal hardware area, conduction losses are greatly reduced, achieving high-efficiency energy conversion under wide voltage and high current conditions.

[0074] According to the switching power supply system provided in the embodiments of this application, the integrated current detection circuit, mode control circuit 130, and auxiliary drive circuit including current slope judgment circuit 180 and charge pump circuit 190 can realize dynamic detection and shunt control of the main power supply current without the need for an input voltage sampling pin. The current slope judgment circuit 180 monitors the reduction slope of the target main power supply current in real time, and precisely controls the rise rate of the gate voltage output by the charge pump through feedback signal when the limit is exceeded, fundamentally avoiding the current oscillation caused by the hard turn-on of the auxiliary tube. With the precise matching of the mode control circuit 130 under buck-boost and charge-discharge conditions, the system can accurately trigger the parallel steady state of the main switch and the auxiliary switch, and achieve a significant reduction in conduction loss with a simplified peripheral circuit, thereby significantly improving the energy conversion efficiency over a wide current and voltage range while ensuring system stability.

[0075] Continue to refer to Figure 2 In some embodiments, the first main switch M1 is connected between the input voltage terminal VBUS and the first switch node SW1; The second main switch transistor M2 is connected between the first switch node SW1 and the ground terminal; The third main switch transistor M3 is connected between the second switch node SW2 and the ground terminal; The fourth main switch transistor M4 is connected between the output voltage terminal VBAT and the second switch node SW2; An inductor L is connected between the first switch node SW1 and the second switch node SW2; One end of the first auxiliary switch M5 is connected to the input voltage terminal VBUS, and the other end is connected to the first switch node SW1; One end of the second auxiliary switch M6 is connected to the output voltage terminal VBAT, and the other end is connected to the second switch node SW2.

[0076] In some embodiments, the switching power supply system may further include a main drive circuit.

[0077] In this embodiment, such as Figure 2 As shown, the main drive circuit includes a first drive circuit 160 and a second drive circuit 170. The first drive circuit 160 is used to drive the first main switch M1 and the second main switch M2, and the second drive circuit 170 is used to drive the third main switch M3 and the fourth main switch M4.

[0078] like Figure 9 This example illustrates the circuit state when the main and auxiliary switches reach a parallel steady state in buck mode. Taking forward charging as an example, the system is in buck mode when the input voltage VBUS is greater than 1.1 times the output voltage VBAT. In this mode, the first drive circuit 160 in the main drive circuit controls the first main switch M1 and the second main switch M2 to alternately switch to complete energy transfer; the second drive circuit 170 controls the third main switch M3 to turn off and controls the fourth main switch M4 to remain normally open; the fourth drive circuit 150 in the auxiliary drive circuit controls the second auxiliary switch M6 to remain normally open. The fourth main switch M4 and the second auxiliary switch M6 form a parallel conduction path. The equivalent on-resistance after the two switches are connected in parallel is significantly reduced. Under the condition of sharing the same large current, the conduction loss P=I^2×R is greatly reduced, thereby improving the high-current conversion efficiency of the system in buck mode.

[0079] like Figure 10This example illustrates the circuit state when the main and auxiliary switches reach a parallel steady state in boost mode. Taking forward charging as an example, the system is in boost mode when the input voltage VBUS is less than 0.9 times the output voltage VBAT. In this mode, the first drive circuit 160 in the main drive circuit controls the first main switch M1 to remain normally open and controls the second main switch M2 to be turned off; the second drive circuit 170 controls the third and fourth main switches M3 and M4 to alternately switch to complete the boost transmission; the third drive circuit 140 in the auxiliary drive circuit controls the first auxiliary switch M5 to remain normally open. The first main switch M1 and the first auxiliary switch M5 form a parallel conduction path. This parallel structure effectively reduces the equivalent on-resistance in boost mode and significantly reduces power loss when large currents flow, thereby improving the system's operating efficiency in boost mode.

[0080] The first current detection circuit 110 and the second current detection circuit 120 have the same structure, which will be discussed below. Figure 8 The structures of the first current detection circuit 110 and the second current detection circuit 120 will be described.

[0081] like Figure 8 As shown, in some embodiments, the current detection circuit module includes: The drains of the first sampling switch M1_N and the second sampling switch M1_1 are both connected to the input voltage terminal VBUS, the sources of the first sampling switch M1_N and the second sampling switch M1_1 are both connected to the first switching node SW1, and the gates of the first sampling switch M1_N and the second sampling switch M1_1 are both used to receive the drive signal. Error amplifier EA; The first resistor R1 is connected between the input voltage terminal VBUS and one input terminal of the error amplifier EA; The second resistor R2 is connected between the input voltage terminal VBUS and the other input terminal of the error amplifier EA; Adjust the switching transistor MP, adjust the gate of the switching transistor MP to the output terminal of the error amplifier EA, and adjust the drain of the switching transistor MP to the common node of the second resistor R2 and the other input terminal of the error amplifier EA. The first capacitor Cs has one end connected to the source of the regulating switch MP through the first switch S1, and the other end grounded. The first switch S1 is connected in parallel with the first capacitor Cs.

[0082] The third drive circuit 140 and the fourth drive circuit 150 have the same structure, which will be discussed below. Figure 7 and Figure 8 The structures of the third drive circuit 140 and the fourth drive circuit 150 are described.

[0083] like Figure 7 A schematic block diagram illustrating the internal structure of the third drive circuit 140 and the fourth drive circuit 150 is provided. The auxiliary drive circuit includes a current detection circuit, a current slope determination circuit 180, and a charge pump circuit 190 connected in sequence. The current detection circuit transmits the detected current signal I_M1 of the target main switch to the current slope determination circuit 180. The current slope determination circuit 180 outputs a feedback control signal DRV_HS1_CTRL (or DRV_HS2_CTRL) based on the slope of the current signal change. This feedback control signal directly acts on the control terminal of the charge pump circuit 190 to control the rise rate of the output voltage DRV_HS1 or DRV_HS2 of the charge pump circuit 190. Through the internal closed-loop feedback loop, the system can precisely achieve controlled linear ramp-up of the gate voltage of the target auxiliary switch at the hardware level.

[0084] Continue to refer to Figure 8 In some embodiments, the current slope determination circuit 180 includes: Current source I1, the power supply terminal of current source I1 is connected to the input voltage terminal VBUS; The second capacitor Cslope is charged by the current source I1 through the second switch S2 to generate a second voltage signal on the second capacitor Cslope that varies with a fixed slope. The second switch S2 operates synchronously with the first switch S1 and the target auxiliary switch tube; The comparator COMP has one input terminal for receiving a second voltage signal and the other input terminal for receiving a first voltage signal. The output terminal of the comparator COMP is connected to the charge pump circuit 190. When the first voltage signal is less than the second voltage signal, the comparator COMP outputs a feedback control signal.

[0085] In this embodiment, the current detection circuit replicates the main switch current through an N:1 current mirror, combined with the formula I=(I_M1) R1) / (N R2) enables current mapping. The replicated current flows through the first capacitor Cs to generate the first voltage signal Vs.

[0086] The reference ramp signal can be generated by charging the second capacitor Cslope with a constant current source I1.

[0087] The first switch S1 and the second switch S2 can be implemented using synchronous MOSFETs, whose gate control signals are from the same source as the drive signal of the target auxiliary switch. When the target auxiliary switch is turned on, S1 and S2 are simultaneously turned off, and the capacitor begins to charge and discharge; when the target auxiliary switch is turned off, S1 and S2 are simultaneously turned on, quickly discharging the residual charge in the capacitor. This ensures that the sampling voltage Vs and the ramp voltage Vslope are both at zero potential before the next shunt operation begins, avoiding comparator misjudgment caused by residual charge in the capacitor.

[0088] In some embodiments, the first switch S1 is opened when the target auxiliary switch is turned on and closed when the target auxiliary switch is turned off to reset the first capacitor Cs.

[0089] In this embodiment, the first capacitor Cs is the energy storage element that generates the first voltage signal Vs. The first switch S1 is connected in parallel across the first capacitor Cs, serving as a forced discharge mechanism. When the target auxiliary switch begins to conduct controlled shunt, the first switch S1 is in the open state, allowing the replicated current from the current sensing circuit to be injected into the first capacitor Cs. This ensures that the voltage across Cs reflects the current real-time current of the target main switch, thereby generating the correct first voltage signal Vs. When the target auxiliary switch completes shunt and turns off, the first switch S1 closes. After the first switch S1 closes, the two ends of the first capacitor Cs are short-circuited, and the charge stored on Cs is instantly discharged to zero, achieving a reset. This reset operation ensures that the residual charge on the first capacitor Cs is completely cleared before the next shunt operation begins, guaranteeing that the next sampling to generate the first voltage signal Vs will strictly start from zero potential. This avoids reference drift and comparator misjudgment caused by residual capacitor charge, ensuring the accuracy of shunt control.

[0090] The control method for a switching power supply system provided in this application can be executed by a control device for the switching power supply system. This application uses the example of a control device executing the control method for a switching power supply system to illustrate the control device for the switching power supply system provided in this application.

[0091] This application also provides a control device for a switching power supply system.

[0092] like Figure 12 As shown, the switching power supply system includes a first main switch transistor, a fourth main switch transistor, a first auxiliary switch transistor connected in parallel across the first main switch transistor, and a second auxiliary switch transistor connected in parallel across the fourth main switch transistor; the control device of the switching power supply system includes a first processing module 1210, a second processing module 1220, and a third processing module 1230.

[0093] The first processing module 1210 is used to detect the input voltage, output voltage, current flowing through the first main switch transistor, and current flowing through the fourth main switch transistor of the switching power supply system. The second processing module 1220 is used to respond to the multiple relationship between the input voltage and the output voltage, and the current flowing through the target main switch meets the preset turn-on conditions, to control the gate voltage of the target auxiliary switch connected in parallel with the target main switch to increase, so that the target auxiliary switch operates in the linear region, thereby increasing the current flowing through the target auxiliary switch and decreasing the current flowing through the target main switch. The third processing module 1230 is used to control the rate of increase of the gate voltage of the target auxiliary switch to decrease in response to the rate of decrease of the current flowing through the target main switch being greater than the first rate threshold, until the target auxiliary switch is fully turned on.

[0094] According to the control device of the switching power supply system provided in the embodiments of this application, the sudden change process of current is transformed into a slope transition with a fixed slope through the controlled opening of the linear region and the slope feedback adjustment of the closed loop. Without significantly increasing the chip area and peripheral circuits, it effectively solves the problems of difficulty in improving efficiency under high current conditions and easy oscillation when parallel opening is activated, and achieves high efficiency, low heat generation and high reliability power conversion effect under high current. Moreover, since the parallel auxiliary tube is only triggered to open under the high current condition of the main tube and does not participate in the operation under light or medium load, it further ensures the overall efficiency performance of the system across the entire load range.

[0095] In some embodiments, the control device of the switching power supply system may further include a fourth processing module, configured to enable preset start-up conditions including: when the switching power supply system is in a charging state. The input voltage is greater than the first multiple of the output voltage, and the current flowing through the fourth main switch is greater than the first current threshold; the target main switch is the fourth main switch, and the target auxiliary switch is the second auxiliary switch; The input voltage is less than the second multiple of the output voltage, and the current flowing through the first main switch is greater than the second current threshold; the target main switch is the first main switch, the target auxiliary switch is the first auxiliary switch, and the second multiple is less than the first multiple.

[0096] In some embodiments, the control device of the switching power supply system may further include a fifth processing module, configured to enable preset start-up conditions including: when the switching power supply system is in a discharging state. The output voltage is greater than the input voltage by a first multiple, and the current flowing through the first main switch is greater than the third current threshold; the target main switch is the first main switch, and the target auxiliary switch is the first auxiliary switch; The output voltage is less than the second multiple of the input voltage, and the current flowing through the fourth main switch is greater than the fourth current threshold; the target main switch is the fourth main switch, the target auxiliary switch is the second auxiliary switch, and the second multiple is less than the first multiple.

[0097] In some embodiments, the third processing module 1230 can also be used for: The current flowing through the target main switch is converted into a first voltage signal, and a ramp voltage signal with a fixed slope is generated. When the first voltage signal is less than the ramp voltage signal, it is determined that the rate of decrease of the current flowing through the target main switch is greater than the first slope threshold.

[0098] The control device of the switching power supply system in this application embodiment can be an electronic device or a component in an electronic device, such as an integrated circuit or a chip. The electronic device can be a terminal or other devices 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. The embodiments of this application do not specifically limit it.

[0099] The control device of the switching power supply system in this application embodiment can be a device with an operating system. This operating system can be a Microsoft (Windows) operating system, an Android operating system, an iOS operating system, or other possible operating systems; this application embodiment does not specifically limit the specific operating system.

[0100] The control device for the switching power supply system provided in this application embodiment can achieve... Figures 1 to 11 The various processes implemented in the method implementation examples will not be described again here to avoid repetition.

[0101] In some embodiments, such as Figure 13As shown, this application embodiment also provides an electronic device 1300, including a processor 1301, a memory 1302, and a computer program stored in the memory 1302 and executable on the processor 1301. When the program is executed by the processor 1301, it implements the various processes of the control method embodiment of the switching power supply system described above and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0102] It should be noted that the electronic devices in the embodiments of this application include the mobile electronic devices and non-mobile electronic devices described above.

[0103] This application also provides a non-transitory computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the various processes of the control method embodiment of the above-described switching power supply system and achieves the same technical effect. To avoid repetition, it will not be described again here.

[0104] The processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0105] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the control method of the above-described switching power supply system.

[0106] The processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0107] This application embodiment also provides a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement the various processes of the control method embodiment of the above-described switching power supply system, and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0108] It should be understood that the chip mentioned in the embodiments of this application may also be referred to as a system-on-a-chip, system chip, chip system, or system-on-a-chip, etc.

[0109] 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.

[0110] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the related technology, can be embodied in the form of a computer software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0111] 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.

[0112] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0113] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A control method for a switching power supply system, characterized in that, The switching power supply system includes a first main switch transistor, a fourth main switch transistor, a first auxiliary switch transistor connected in parallel across the first main switch transistor, and a second auxiliary switch transistor connected in parallel across the fourth main switch transistor; the method includes: The input voltage, output voltage, current flowing through the first main switch transistor, and current flowing through the fourth main switch transistor of the switching power supply system are detected. In response to the multiple relationship between the input voltage and the output voltage, and the fact that the current flowing through the target main switch meets the preset turn-on condition, the gate voltage of the target auxiliary switch connected in parallel with the target main switch is increased, so that the target auxiliary switch operates in the linear region, thereby increasing the current flowing through the target auxiliary switch and decreasing the current flowing through the target main switch. In response to the current flowing through the target main switch decreasing at a rate greater than a first rate threshold, the gate voltage of the target auxiliary switch is controlled to decrease at a rate until the target auxiliary switch is fully turned on.

2. The control method for the switching power supply system according to claim 1, characterized in that, When the switching power supply system is in a charging state, the preset activation conditions include: The input voltage is greater than the output voltage by a first multiple, and the current flowing through the fourth main switch is greater than the first current threshold; the target main switch is the fourth main switch, and the target auxiliary switch is the second auxiliary switch; The input voltage is less than the second multiple of the output voltage, and the current flowing through the first main switch is greater than the second current threshold; the target main switch is the first main switch, the target auxiliary switch is the first auxiliary switch, and the second multiple is less than the first multiple.

3. The control method for the switching power supply system according to claim 1, characterized in that, When the switching power supply system is in a discharging state, the preset activation conditions include: The output voltage is greater than the input voltage by a first multiple, and the current flowing through the first main switch is greater than the third current threshold; the target main switch is the first main switch, and the target auxiliary switch is the first auxiliary switch; The output voltage is less than the second multiple of the input voltage, and the current flowing through the fourth main switch is greater than the fourth current threshold; the target main switch is the fourth main switch, the target auxiliary switch is the second auxiliary switch, and the second multiple is less than the first multiple.

4. The control method for a switching power supply system according to any one of claims 1-3, characterized in that, Determining that the rate of decrease in the current flowing through the target main switch is greater than a first slope threshold includes: The current flowing through the target main switch is converted into a first voltage signal, and a ramp voltage signal with a fixed slope is generated. When the first voltage signal is less than the ramp voltage signal, it is determined that the rate of decrease of the current flowing through the target main switch is greater than the first slope threshold.

5. A switching power supply system, characterized in that, include: The main switch module includes a first main switch (M1), a second main switch (M2), a third main switch (M3), and a fourth main switch (M4). The auxiliary switching module includes a first auxiliary switching transistor (M5) connected in parallel across the first main switching transistor (M1) and a second auxiliary switching transistor (M6) connected in parallel across the fourth main switching transistor (M4). A current detection circuit module, connected to the first main switch (M1) and the fourth main switch (M4), includes a first current detection circuit (110) and a second current detection circuit (120). The first current detection circuit (110) is used to detect the current of the first main switch (M1), and the second current detection circuit (120) is used to detect the current of the fourth main switch (M4). The mode control circuit (130) is connected to the current detection circuit module and is used to generate a first enable signal and a second enable signal based on the input voltage, the output voltage, the current of the first main switch (M1) and the current of the fourth main switch (M4). An auxiliary drive circuit, connected to the mode control circuit and the current detection circuit module, includes a third drive circuit (140) and a fourth drive circuit (150). The third drive circuit (140) is used to drive the first auxiliary switch (M5) in response to the first enable signal, and the fourth drive circuit (150) is used to drive the second auxiliary switch (M6) in response to the second enable signal. The third driving circuit (140) and the fourth driving circuit (150) respectively include a current slope judgment circuit (180) and a charge pump circuit (190). The current slope judgment circuit (180) is used to detect the current reduction slope of the corresponding target main switch, and output a feedback control signal when the current reduction slope is greater than the first slope threshold; the charge pump circuit (190) is used to control the rise rate of the gate voltage of the corresponding target auxiliary switch according to the feedback control signal.

6. The switching power supply system according to claim 5, characterized in that, One end of the first auxiliary switch (M5) is connected to the input voltage terminal (VBUS), and the other end is connected to the first switching node (SW1). One end of the second auxiliary switch (M6) is connected to the output voltage terminal (VBAT), and the other end is connected to the second switching node (SW2). The current detection circuit module includes: The first sampling switch (M1_N) and the second sampling switch (M1_1) are connected to the input voltage terminal (VBUS), and their sources are connected to the first switching node (SW1). The gates of the first sampling switch (M1_N) and the second sampling switch (M1_1) are used to receive drive signals. The first resistor (R1) is connected between the input voltage terminal (VBUS) and one input terminal of the error amplifier (EA); The second resistor (R2) is connected between the input voltage terminal (VBUS) and the other input terminal of the error amplifier (EA); An adjustment switch (MP) is provided, the gate of which is connected to the output of the error amplifier (EA), and the drain of which is connected to the common node of the second resistor (R2) and another input of the error amplifier (EA). The first capacitor (Cs) has one end connected to the source of the regulating switch (MP) through the first switch (S1), and the other end grounded. The first switch (S1) is connected in parallel with the first capacitor (Cs).

7. The switching power supply system according to claim 6, characterized in that, The current slope determination circuit (180) includes: A current source (I1) is provided, with its power supply terminal connected to the input voltage terminal (VBUS). The second capacitor (Cslope) is charged by the current source (I1) through the second switch (S2) to generate a second voltage signal on the second capacitor (Cslope) that varies with a fixed slope; The second switch (S2) operates synchronously with the first switch (S1) and the target auxiliary switch tube; A comparator (COMP) is provided, with one input terminal for receiving the second voltage signal and the other input terminal for receiving the first voltage signal. The output terminal of the comparator (COMP) is connected to the charge pump circuit (190). When the first voltage signal is less than the second voltage signal, the comparator (COMP) outputs the feedback control signal.

8. A control device for a switching power supply system, characterized in that, The switching power supply system includes a first main switching transistor, a fourth main switching transistor, a first auxiliary switching transistor connected in parallel across the first main switching transistor, and a second auxiliary switching transistor connected in parallel across the fourth main switching transistor; the device includes: The first processing module is used to detect the input voltage, output voltage, current flowing through the first main switch transistor, and current flowing through the fourth main switch transistor of the switching power supply system. The second processing module is used to respond to the multiple relationship between the input voltage and the output voltage, and the fact that the current flowing through the target main switch meets the preset turn-on conditions, to control the gate voltage of the target auxiliary switch connected in parallel with the target main switch to increase, so that the target auxiliary switch operates in the linear region, thereby increasing the current flowing through the target auxiliary switch and decreasing the current flowing through the target main switch. The third processing module is used to control the rate of increase of the gate voltage of the target auxiliary switch to decrease in response to the current decrease slope of the target main switch being greater than a first slope threshold, until the target auxiliary switch is fully turned on.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the control method of the switching power supply system as described in any one of claims 1-4.

10. A chip, the chip comprising a processor and a communication interface, the communication interface being coupled to the processor, characterized in that, The processor is used to run programs or instructions, and when the processor executes the programs or instructions, it implements the control method of the switching power supply system as described in any one of claims 1-4.

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