Wide input buck-boost switching power converter and control method

Abstract

The application discloses a wide input buck-boost switching power supply converter and a control method. The converter comprises an error amplification module, a current sampling circuit, a comparator array, a conduction time generator, an off time generator, a dynamic mode selection circuit, a logic control circuit, a zero-crossing detection circuit and a four-way power switch tube module. The conduction time generator and the off time generator with adaptive constant conduction and off are introduced to optimize the efficiency and performance of the converter. The conduction time and the off time are accurately adjusted to realize smooth transition between different working modes, improve the stability and efficiency of the converter, and accurately adjust the output voltage in a wide input voltage range, thereby achieving excellent input adaptability. In the buck mode, adaptive constant conduction time control is adopted, and in the boost mode, adaptive constant off time control is adopted, so that the system maintains optimal dynamic response and stability under different conversion conditions.

Description

Technical Field

[0001] This invention belongs to the field of power converters in power management circuits, specifically relating to a wide-input buck-boost switching power converter and its control method. Background Technology

[0002] With the widespread adoption of portable electronic devices, especially smartphones, tablets, and wearable devices, the demands on power management systems are increasing. Ensuring a stable output voltage, particularly under conditions of significant input voltage fluctuations, has become a critical design challenge. Buck-Boost converters, capable of providing stable output voltages under varying input voltage conditions, have found widespread application in these situations. However, existing buck-boost converters still have shortcomings in efficiency, mode switching, and noise suppression, especially exhibiting low efficiency under light load conditions. Furthermore, switching between different operating modes (such as Buck mode, Boost mode, and buck-boost mode) can generate significant voltage fluctuations and electromagnetic interference (EMI).

[0003] Most existing buck-boost converters employ constant on-time (COT) control or peak current mode control strategies, which can provide relatively stable output voltage under certain conditions. However, these traditional methods are prone to instability in efficiency, voltage fluctuations, and high electromagnetic interference (EMI) when the load varies significantly. During mode switching in buck-boost converters, especially from Buck mode to Boost mode, output voltage fluctuations or instability are easily caused by inductor current mismatch and feedback loop lag. These fluctuations not only affect the normal operation of the device but may also interfere with surrounding electronic equipment, leading to EMI problems. Furthermore, light-load efficiency is a major challenge for traditional Buck-Boost converters. Under light-load conditions, many traditional control methods fail to effectively switch to low-frequency operating states, resulting in excessive switching losses and a significant drop in efficiency. Although some existing designs attempt to improve this by adjusting control strategies, they often struggle to achieve ideal efficiency across a wide load range, especially under low power requirements, where efficiency improvements are limited.

[0004] Existing Buck-Boost converters have the following drawbacks:

[0005] The control loop design is complex and difficult to standardize: In existing technologies, buck, boost, and buck-boost modes often require different types of control strategies. For example, peak current mode control in buck mode needs to address subharmonic instability issues when the duty cycle is greater than 50%, usually requiring additional slope compensation; while in boost mode, the system is affected by the right half-plane zeros, limiting dynamic performance. Currently, there is a lack of a unified control architecture applicable to all three operating modes, leading to complex control system design and difficulties in adjusting the compensation network.

[0006] The complexity of timing generation and the inadequacy of frequency stability are significant drawbacks: Most existing Buck-Boost solutions employ modulation methods based on fixed frequencies and clocks, which limit their transient response performance and loop design flexibility. While alternatives such as fixed off-time control have been applied in single Buck or Boost converters, the different off-time calculation methods between Buck and Boost modes make it difficult for existing technologies to achieve seamless adaptive off-time generation across all operating regions using a single circuit. Consequently, true quasi-constant switching frequency operation cannot be achieved across the entire operating range.

[0007] Optimizing performance and energy efficiency in the transition region is challenging: Existing Buck-Boost converters typically switch between three modes—buck, boost, and buck-boost transition regions—but the switching thresholds between these modes are difficult to determine precisely. Operating in the transition region where the input voltage is close to the output voltage is one of the core challenges in designing this type of converter. The size and detection mechanism of this region directly affect the smoothness of mode switching, the magnitude of output ripple, and the overall system efficiency. Existing technologies often lack the ability to adaptively optimize the size of the transition region, making it difficult to ensure smooth transitions between modes while simultaneously achieving low-load efficiency and steady-state performance.

[0008] In summary, existing Buck-Boost converters still have shortcomings in several aspects, especially in terms of large load variations, unstable mode switching, and electromagnetic interference. There is an urgent need to develop more efficient, stable, and smooth mode switching control strategies to meet the growing demand for efficient power management. Summary of the Invention

[0009] To address the aforementioned problems in the prior art, this invention provides a wide-input buck-boost switching power supply converter and its control method. The technical problem to be solved by this invention is achieved through the following technical solution:

[0010] In a first aspect, the present invention provides a wide-input buck-boost switching power supply converter, comprising:

[0011] The circuit includes an error amplifier module, a current sampling circuit, a comparator array, an on-time generator, an off-time generator, a dynamic mode selection circuit, a logic control circuit, a zero-crossing detection circuit, and a four-channel power switch module; among which,

[0012] The error amplification module uses a type II compensation network to obtain the output voltage signal through its own feedback resistor network, and then outputs the error voltage after comparing the output voltage signal with the reference voltage.

[0013] The current sampling circuit collects the corresponding current in the four power switching transistor modules in real time and generates the corresponding current detection signal.

[0014] The comparator triggers the corresponding on-time generator and off-time generator by comparing the current detection signal with the error voltage.

[0015] The on-time generator, triggered by the corresponding comparator, counts the on-time based on the input voltage and the output voltage, and outputs an on-time control signal.

[0016] The shutdown time generator, triggered by the corresponding comparator, counts the shutdown time based on the input voltage and the output voltage, and outputs a shutdown time control signal.

[0017] The dynamic mode selection circuit outputs a corresponding mode selection signal based on the relationship between the input voltage and the output voltage.

[0018] The logic control circuit generates drive signals corresponding to different modes based on the mode selection signal, the on-time control signal, and the off-time control signal. At the same time, it detects the zero-crossing point of the current in the load inductor in the four power switch modules through the zero-crossing detection circuit to determine whether the converter enters the light load mode. In the light load mode, a pause phase is introduced to enable the converter to perform pulse cross-cycle modulation in order to reduce the frequency and loss of the converter.

[0019] The four-channel power switching module outputs the corresponding conversion voltage according to the drive signal corresponding to different modes.

[0020] In one embodiment of the present invention, the error amplification module includes:

[0021] The system consists of a feedback resistor network, an error amplifier, and a Type II compensation network; among which,

[0022] The input terminal of the feedback resistor network is connected to the output voltage signal, and the output terminal is connected to the inverting input terminal of the error amplifier.

[0023] The non-inverting input terminal of the error amplifier is connected to a reference voltage, and the output terminal serves as the output terminal of the error amplification module.

[0024] The input terminal of the type II compensation network is connected to the output terminal of the feedback resistor network, and the output terminal is connected to the output terminal of the error amplifier.

[0025] In one embodiment of the present invention, the current detection signal includes a valley current and a peak current; the comparator array triggers corresponding on-time generators and off-time generators by comparing the current detection signal with an error voltage, including:

[0026] The first comparator in the comparator array corresponds to the voltage V of the valley current. CS_BK With error voltage V EA Comparison, when V EA Greater than V CS_BK At that time, the first trigger signal CMP is output. BK This triggers the on-time generator;

[0027] The second comparator in the comparator array corresponds to the voltage V of the peak current. CS_BT With error voltage V EA Comparison, when V EA Less than V CS_BT At that time, the second trigger signal CMP is output. BT This triggers the shutdown time generator.

[0028] In one embodiment of the present invention, the on-time generator, triggered by a corresponding comparator, times the on-time based on the input voltage and the output voltage, and outputs an on-time control signal, including:

[0029] The conduction time generator, triggered by the first comparator, when the input voltage V... IN Greater than the output voltage V OUT At that time, the conduction time generation circuit in the conduction time generator is based on the input voltage V. IN Output voltage V OUT and the first trigger signal CMP BK Output conduction signal T ON_BK The RS flip-flop in the conduction time generator outputs the conduction time control signal PWM. BK .

[0030] In one embodiment of the present invention, the turn-off time generator, triggered by a corresponding comparator, times the turn-off time based on the input voltage and the output voltage, and outputs a turn-off time control signal, including:

[0031] The off-time generator, triggered by the second comparator, when the input voltage V... IN Less than the output voltage V OUT At that time, the turn-off time generation circuit in the turn-off time generator is based on the input voltage V. IN Output voltage VOUT Second trigger signal CMP BT Output off signal T OFF_BT The RS flip-flop in the turn-off time generator outputs the turn-off time control signal PWM. BT .

[0032] In one embodiment of the present invention, the dynamic mode selection circuit outputs a corresponding mode selection signal based on the relationship between the input voltage and the output voltage, including:

[0033] When the input voltage V IN Greater than the output voltage V OUT At that time, the dynamic mode selection circuit will output a high-level enable signal EN. BK Low-level enable signal EN BB and the low-level enable signal EN BT Output as the mode selection signal corresponding to Buck mode;

[0034] When the input voltage V IN Less than the output voltage V OUT At that time, the dynamic mode selection circuit will output a high-level enable signal EN. BT Low-level enable signal EN BB and the low-level enable signal EN BK Output as the mode selection signal corresponding to Boost mode;

[0035] When the input voltage V IN With output voltage V OUT When the difference is within a preset range, the dynamic mode selection circuit will send a high-level enable signal EN. BB Low-level enable signal EN BK and the low-level enable signal EN BT This output serves as the mode selection signal for the Buck-Boost mode.

[0036] In one embodiment of the present invention, the logic control circuit generates drive signals corresponding to different modes based on a mode selection signal, an on-time control signal, and an off-time control signal, including:

[0037] The logic control circuit outputs an adaptive constant on-time control signal as the driving signal corresponding to the Buck mode, based on the mode selection signal and the on-time control signal corresponding to the Buck mode.

[0038] Based on the mode selection signal and turn-off time control signal corresponding to the Boost mode, an adaptive constant turn-off time control signal is output as the driving signal corresponding to the Boost mode.

[0039] Based on the mode selection signal, on-time control signal, and off-time control signal corresponding to the Buck-Boost mode, a quasi-fixed frequency de-modulated signal is output as the driving signal corresponding to the Buck-Boost mode.

[0040] In one embodiment of the present invention, the four-channel power switch module outputs a corresponding conversion voltage according to the drive signal corresponding to different modes, including:

[0041] When the drive signal is the drive signal corresponding to Buck mode, the error voltage V EA The voltage V corresponding to the peak current is greater than the valley current. CS_BK At that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After the preset conduction time has elapsed, the conduction time generator controls its own switching transistor M to turn on. A Close, switch transistor M B and switching transistor M D When the circuit is turned on, the corresponding conversion voltage is output.

[0042] When the drive signal is the drive signal corresponding to Boost mode, the error voltage V EA The voltage V less than the peak current CS_BT At that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After a preset turn-off time, the turn-on and turn-off time generator controls its own switching transistor M. A Close, switch transistor M C When the circuit is turned on, the corresponding conversion voltage is output.

[0043] When the drive signal is the drive signal corresponding to Buck-Boost mode, the error voltage V EA The voltage V corresponding to the peak current is greater than the valley current. CS_BK At that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After the preset conduction time has elapsed, the conduction time generator controls its own switching transistor M to turn on. A On / off transistor M C On; when the error voltage V EA The voltage V less than the peak current CS_BT At that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After a preset turn-off time, the turn-on and turn-off time generator controls its own switching transistor M. A Close, switch transistor M B and switching transistor M DWhen the circuit is turned on, the corresponding conversion voltage is output.

[0044] In one embodiment of the present invention, the zero-crossing detection circuit detects the zero-crossing point of the current in the load inductor in the four-channel power switch module to determine whether the converter enters a light-load mode. In the light-load mode, a pause phase is introduced, enabling the converter to perform pulse cross-cycle modulation, including:

[0045] When the zero-crossing detection circuit detects that the load current of the load inductor in the four-channel power switch module is less than the preset zero-current detection threshold, the converter enters a light-load mode, activates the pause phase, and performs pulse cross-cycle modulation. The pause phase will be maintained until the error voltage V. EA The voltage V corresponding to the peak current is greater than the valley current. CS_BK Afterwards, the control converter resumes normal operation.

[0046] In a second aspect, the present invention provides a wide-input buck-boost switching power supply conversion control method, applied to the wide-input buck-boost switching power supply converter as described in the first aspect, the control method comprising:

[0047] The output voltage signal is obtained by using the feedback resistor network in the error amplifier module, and the error voltage is output after comparing the output voltage signal with the reference voltage.

[0048] The current sampling circuit is used to collect the inductor current in real time and generate the corresponding current detection signal.

[0049] A comparator is used to compare the current detection signal with the error voltage, triggering the corresponding on-time generation circuit and off-time generation circuit.

[0050] When triggered by the corresponding comparator, the on-time generator calculates the on-time based on the input and output voltages and outputs an on-time control signal.

[0051] When triggered by the corresponding comparator, the shutdown time generator calculates the shutdown time based on the input voltage and output voltage, and outputs a shutdown time control signal.

[0052] A dynamic mode selection circuit is used to output a corresponding mode selection signal based on the relationship between the input voltage and the output voltage.

[0053] Based on the mode selection signal, on-time control signal, and off-time control signal, the logic control circuit generates drive signals corresponding to different modes. At the same time, the zero-crossing detection circuit detects the zero-crossing point of the current in the load inductor in the four power switch modules to determine whether the converter enters the light load mode. In the light load mode, a pause phase is introduced to make the converter enter the pulse cross-cycle modulation mode to reduce the converter's frequency and loss.

[0054] Based on the drive signals corresponding to different modes, the four power switching transistor modules are controlled to output the corresponding conversion voltages.

[0055] The beneficial effects of this invention are:

[0056] The solution provided by this invention optimizes the efficiency and performance of the converter by introducing adaptive constant on-time and off-time generators. By precisely adjusting the on-time and off-time of the switches, a smooth transition between different operating modes is achieved, thereby improving the stability and efficiency of the converter. Within a wide input voltage range, it can efficiently and stably achieve precise adjustment of the output voltage, exhibiting excellent input adaptability. Adaptive constant on-time control is used in buck mode, and adaptive constant off-time control is used in boost mode, ensuring that the system maintains optimized dynamic response and stability under different conversion conditions.

[0057] Furthermore, in the buck-boost mode, the pseudo-fixed frequency reduction modulation mechanism improves system efficiency and effectively suppresses electromagnetic interference while ensuring output regulation accuracy. By introducing a light-load control strategy that combines hybrid pulse frequency modulation and pulse cross-cycle modulation, and enabling the pause working phase under light-load conditions, the conversion efficiency of the system under light-load conditions is significantly improved. Attached Figure Description

[0058] Figure 1 This is a schematic diagram of a wide-input buck-boost switching power supply converter provided in an embodiment of the present invention;

[0059] Figure 2 This is a schematic diagram of a wide-input buck-boost switching power supply converter provided in an embodiment of the present invention;

[0060] Figure 3 This is a schematic diagram illustrating the state and operating mode of a wide-input buck-boost switching power supply converter provided in an embodiment of the present invention;

[0061] Figure 4 This is a schematic diagram of the operating waveforms of a wide input buck-boost switching power supply converter under different input voltages, provided in an embodiment of the present invention.

[0062] Figure 5 A schematic diagram of the on / off time generation circuit of a wide input buck-boost switching power supply converter provided in an embodiment of the present invention;

[0063] Figure 6 This is a schematic diagram of the control logic of a logic control circuit in a wide-input buck-boost switching power converter provided in an embodiment of the present invention;

[0064] Figures 7a-7cTiming diagrams of a wide-input buck-boost switching power supply converter in different modes provided in embodiments of the present invention;

[0065] Figure 8 A schematic diagram of the dynamic mode selection circuit for a wide input buck-boost switching power supply converter provided in an embodiment of the present invention;

[0066] Figure 9 This is a schematic diagram illustrating the steps of a wide-input buck-boost switching power supply conversion control method provided in an embodiment of the present invention. Detailed Implementation

[0067] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0068] This invention provides a wide-input buck-boost switching power supply converter and its control method.

[0069] Below, we will first introduce a wide-input buck-boost switching power supply converter provided in the embodiments of the present invention.

[0070] The present invention provides a wide input buck-boost switching power supply converter, such as... Figure 1 As shown, it may include:

[0071] The circuit includes an error amplifier module, a current sampling circuit, a comparator array, an on-time generator, an off-time generator, a dynamic mode selection circuit, a logic control circuit, a zero-crossing detection circuit, and a four-channel power switch module; among which,

[0072] The error amplification module uses a type II compensation network to obtain the output voltage signal through its own feedback resistor network. After comparing the output voltage signal with the reference voltage, it outputs the error voltage.

[0073] The current sampling circuit collects the corresponding current in the four power switching transistor modules in real time and generates the corresponding current detection signal.

[0074] The comparator, by comparing the current detection signal with the error voltage, triggers the corresponding on-time generator and off-time generator;

[0075] The on-time generator, triggered by the corresponding comparator, counts the on-time based on the input voltage and output voltage, and outputs an on-time control signal.

[0076] The turn-off time generator, triggered by the corresponding comparator, counts the turn-off time based on the input voltage and output voltage, and outputs a turn-off time control signal.

[0077] The dynamic mode selection circuit outputs a corresponding mode selection signal based on the relationship between the input voltage and the output voltage.

[0078] The logic control circuit generates drive signals corresponding to different modes based on the mode selection signal, the on-time control signal, and the off-time control signal. At the same time, the zero-crossing detection circuit detects the zero-crossing point of the current in the load inductor in the four power switching transistor modules to determine whether the converter enters the light load mode. In the light load mode, a pause phase is introduced to make the converter enter the pulse cross-cycle modulation mode to reduce the converter's frequency and loss.

[0079] The four-channel power switching module outputs the corresponding conversion voltage according to the drive signal corresponding to different modes.

[0080] The converter proposed in this embodiment employs adaptive constant on-time control in buck mode, adaptive constant off-time control in boost mode, and a quasi-fixed frequency reduction modulation mechanism in buck-boost mode. Simultaneously, a zero-crossing detection circuit introduces a pause phase under light load conditions, achieving efficient power conversion over a wide input voltage range. By meticulously controlling the converter's operating modes, efficient and stable power output is ensured under various operating conditions.

[0081] This invention proposes a wide-input buck-boost switching power supply converter to address the shortcomings of traditional Buck-Boost converters in terms of efficiency, stability, and electromagnetic interference (EMI). This technical solution introduces Type II compensation, which modifies the error voltage output by the error amplifier to match the voltage V corresponding to the valley current. CS_BK The voltage V corresponding to the peak current CS_BT By comparing and precisely adjusting the on-time and off-time generators, a smooth transition between different operating modes is achieved, improving efficiency and effectively reducing voltage fluctuations and electromagnetic interference (EMI). This converter employs hybrid current-mode constant on / off time (MCCOT) control to effectively regulate a stable output voltage and adapt to a wide input voltage range. In buck mode, adaptive constant on-time control is used; in boost mode, adaptive constant off-time control is used; and in buck-boost mode, pseudo-fixed frequency modulation is employed to ensure stable output regulation and high efficiency while minimizing EMI. To further improve efficiency under light load conditions, a pause phase is introduced and combined with pulse frequency modulation (PFM), significantly improving efficiency under light load.

[0082] To facilitate understanding, the following will combine... Figure 2The diagram shown illustrates the structure of a wide-input buck-boost switching power supply converter, and introduces each module of the converter.

[0083] Error amplification module, such as Figure 2 As shown, it may include:

[0084] The system consists of a feedback resistor network, an error amplifier, and a Type II compensation network; among which,

[0085] The input of the feedback resistor network is connected to the output voltage signal, and the output is connected to the inverting input of the error amplifier.

[0086] The non-inverting input of the error amplifier is connected to a reference voltage, and its output is used as the output of the error amplification module.

[0087] The input of the type II compensation network is connected to the output of the feedback resistor network, and the output is connected to the output of the error amplifier.

[0088] Specifically, the feedback resistor network may include resistors R1 and R2, wherein the first end of resistor R1 serves as the input terminal of the feedback resistor network, and the second end is connected to the first end of resistor R2 as the output terminal of the feedback resistor network; the second end of resistor R2 is grounded. The Type II compensation network may include a capacitor structure and an RC structure connected in parallel. The capacitor structure includes a first capacitor, and the RC structure includes a resistor and a second capacitor connected in series; the first end of the first capacitor serves as the input terminal of the Type II compensation network, and the second end serves as the output terminal of the Type II compensation network.

[0089] The error amplification module uses a type II compensation network to obtain the output voltage signal through its own feedback resistor network. After comparing the output voltage signal with the reference voltage, it outputs the error voltage.

[0090] The current sampling circuit acquires the inductor current in real time and generates a corresponding current detection signal. The current detection signal can include valley current and peak current.

[0091] The comparator triggers the corresponding on-time generation circuit and off-time generation circuit by comparing the current detection signal with the error voltage.

[0092] The comparator array triggers corresponding on-time and off-time generators by comparing the current detection signal with the error voltage. This process can include:

[0093] The first comparator in the comparator array corresponds to the voltage V of the valley current. CS_BK With error voltage V EA When comparing, when V EA Greater than V CS_BK At that time, the first trigger signal CMP is output. BK This triggers the on-time generator;

[0094] The second comparator in the comparator array corresponds to the voltage V of the peak current. CS_BT With error voltage V EA Comparison, when V EA Less than V CS_BT At that time, the second trigger signal CMP is output. BT This triggers the shutdown time generator.

[0095] The on-time generator may include an on-time generation circuit and a first RS flip-flop; wherein, the on-time generation circuit is connected to the input voltage V. IN Output voltage V OUT First trigger signal CMP BK and the on-time control signal PWM BK The output terminal outputs a conduction signal T. ON_BK The R terminal of the first RS flip-flop is connected to the on signal T. ON_BK The S-terminal receives the first trigger signal CMP. BK The Q-terminal outputs a PWM (Power-On Control Signal) for conduction time. BK , The end is suspended in the air.

[0096] The on-time generator, triggered by a corresponding comparator, times the on-time based on the input and output voltages, and outputs an on-time control signal, which may include:

[0097] The on-time generator, triggered by the first comparator, when the input voltage V... IN Greater than the output voltage V OUT At that time, the conduction time generation circuit in the conduction time generator is based on the input voltage V. IN Output voltage V OUT and the first trigger signal CMP BK Output conduction signal T ON_BK The RS flip-flop in the conduction time generator outputs the conduction time control signal PWM. BK .

[0098] By controlling the on-time signal PWM BK Feedback is sent to the conduction time generation circuit, causing T in the conduction time generation circuit to... ON The timer generates the correct timing.

[0099] The turn-off time generator may include a turn-off time generation circuit and a second RS flip-flop; wherein, the turn-off time generation circuit is connected to the input voltage V. IN Output voltage V OUT Second trigger signal CMP BT and the off-time control signal PWM BTThe output terminal outputs a turn-off signal T. OFF_BT The R terminal of the second RS flip-flop is connected to the turn-off signal T. OFF_BT The S-terminal receives the second trigger signal CMP. BT The Q-terminal outputs the PWM (Power Width Modulation) signal for off-time control. BT , The end is suspended in the air.

[0100] The turn-off time generator, triggered by a corresponding comparator, times the turn-off time based on the input and output voltages and outputs a turn-off time control signal, which may include:

[0101] The turn-off time generator, triggered by the second comparator, when the input voltage V... IN Less than the output voltage V OUT At that time, the turn-off time generation circuit in the turn-off time generator is based on the input voltage V. IN Output voltage V OUT Second trigger signal CMP BT Output off signal T OFF_BT The RS flip-flop in the turn-off time generator outputs the turn-off time control signal PWM. BT .

[0102] By controlling the off-time signal PWM BT Feedback is sent to the turn-off time generation circuit, causing T in the turn-off time generation circuit to... OFF The timer generates the correct timing.

[0103] The dynamic mode selection circuit outputs a corresponding mode selection signal based on the relationship between the input voltage and the output voltage, and may include:

[0104] When the input voltage V IN Greater than the output voltage V OUT At this time, the dynamic mode selection circuit will activate the high-level enable signal EN. BK Low-level enable signal EN BB and the low-level enable signal EN BT Output as the mode selection signal corresponding to Buck mode;

[0105] When the input voltage V IN Less than the output voltage V OUT At this time, the dynamic mode selection circuit will activate the high-level enable signal EN. BT Low-level enable signal EN BB and the low-level enable signal EN BK Output as the mode selection signal corresponding to Boost mode;

[0106] When the input voltage V IN With output voltage V OUTWhen the difference is within a preset range, the dynamic mode selection circuit will send a high-level enable signal EN. BB Low-level enable signal EN BK and the low-level enable signal EN BT This output serves as the mode selection signal for the Buck-Boost mode.

[0107] The logic control circuit generates drive signals corresponding to different modes based on the mode selection signal, the on-time control signal, and the off-time control signal. At the same time, the zero-crossing detection circuit detects the zero-crossing point of the current in the load inductor in the four power switching transistor modules to determine whether the converter enters the light load mode. In the light load mode, a pause phase is introduced to make the converter enter the pulse cross-cycle modulation mode to reduce the converter's frequency and loss.

[0108] The logic control circuit, based on the mode selection signal, the on-time control signal, and the off-time control signal, generates drive signals corresponding to different modes, which may include:

[0109] The logic control circuit outputs an adaptive constant on-time control signal as the drive signal corresponding to the Buck mode, based on the mode selection signal and the on-time control signal corresponding to the Buck mode.

[0110] Based on the mode selection signal and turn-off time control signal corresponding to the Boost mode, an adaptive constant turn-off time control signal is output as the driving signal corresponding to the Boost mode.

[0111] Based on the mode selection signal, on-time control signal, and off-time control signal corresponding to the Buck-Boost mode, a quasi-fixed frequency de-modulated signal is output as the driving signal corresponding to the Buck-Boost mode.

[0112] Four-channel power switching transistor module, such as Figure 2 As shown, it may include:

[0113] Switching transistor M A Switching transistor M B Switching transistor M C Switching transistor M D Switch SW1, Switch SW2, Voltage source, Load inductor L, Output capacitor C OUT and output resistance R OUT ;in,

[0114] Switching transistor M A The source is connected to the first terminal of switch SW1, the gate is connected to the first output terminal of the logic control circuit, and the drain is connected to the first terminal of the voltage source and the low dropout linear regulator LDO in the external circuit, respectively.

[0115] Switching transistor M B The source is grounded, the gate is connected to the second output terminal of the logic control circuit, and the drain is connected to the second terminal of switch SW1.

[0116] Switching transistor M C The source is grounded, the gate is connected to the third output terminal of the logic control circuit, and the drain is connected to the second terminal of switch SW2.

[0117] Switching transistor M D The source and output capacitor C OUT The first terminal is connected, the gate is connected to the fourth output terminal of the logic control circuit, and the drain is connected to the third terminal of switch SW2.

[0118] The second terminal of the voltage source is grounded;

[0119] The first terminal of the load inductor L is connected to the third terminal of switch SW1, and the second terminal is connected to the first terminal of switch SW2.

[0120] Output capacitor C OUT The first terminal and the output resistor R OUT The first end is connected, and the second end is grounded;

[0121] Output resistance R OUT The first terminal serves as the output terminal of the four-channel power switching module, while the second terminal is grounded.

[0122] The external circuitry may include a low-dropout linear regulator (LDO) and a bandgap reference circuit (BGR) connected in series; wherein the bandgap reference circuit (BGR) provides a stable reference voltage V to the converter based on the voltage AVDD output by the LDO. REF .

[0123] The four-channel power switching module outputs corresponding conversion voltages based on the drive signals for different modes, which may include:

[0124] When the drive signal is the drive signal corresponding to Buck mode, the error voltage V EA The voltage V corresponding to the peak current is greater than the valley current. CS_BK At that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After the preset conduction time has elapsed, the conduction time generator controls its own switching transistor M to turn on. A Close, switch transistor M B and switching transistor M D When the circuit is turned on, the corresponding conversion voltage is output.

[0125] When the drive signal is the drive signal corresponding to Boost mode, the error voltage V EA The voltage V less than the peak current CS_BTAt that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After a preset turn-off time, the turn-on and turn-off time generator controls its own switching transistor M. A Close, switch transistor M C When the circuit is turned on, the corresponding conversion voltage is output.

[0126] When the drive signal is the drive signal corresponding to Buck-Boost mode, the error voltage V EA The voltage V corresponding to the peak current is greater than the valley current. CS_BK At that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After the preset conduction time has elapsed, the conduction time generator controls its own switching transistor M to turn on. A On / off transistor M C On; when the error voltage V EA The voltage V less than the peak current CS_BT At that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After a preset turn-off time, the turn-on and turn-off time generator controls its own switching transistor M. A Close, switch transistor M B and switching transistor M D When the circuit is turned on, the corresponding conversion voltage is output.

[0127] The zero-crossing detection circuit detects the zero-crossing point of the current in the load inductor of the four power switching transistor module to determine whether the converter enters light-load mode. In light-load mode, a pause phase is introduced, enabling the converter to perform pulse cross-cycle modulation. This process may include:

[0128] When the zero-crossing detection circuit detects that the load current of the load inductor in the four-channel power switching module is less than the preset zero-current detection threshold, the converter enters a light-load mode, activating the pause phase. The converter performs pulse cross-cycle modulation, and the pause phase will be maintained until the error voltage V. EA The voltage V corresponding to the peak current is greater than the valley current. CS_BK Afterwards, the control converter resumes normal operation.

[0129] Understandably, this invention employs a wide-input buck-boost switching power supply converter based on hybrid current-mode constant on / off time (MCCOT) control to address the shortcomings of traditional converters in terms of efficiency, stability, and electromagnetic interference (EMI). This converter introduces a Type II compensation network to compare the error voltage output from the error amplification module with the comparison current detection signal, precisely adjusting the operation of the on-time generator and the off-time generator to achieve a smooth transition between different operating modes. This converter not only improves operating efficiency but also effectively reduces voltage fluctuations and EMI.

[0130] This invention, through meticulous control of the converter's operating mode, ensures efficient and stable power output under various operating conditions. During operation, when the error voltage V output by the error amplifier... EA The voltage V corresponding to the peak current is greater than the valley current. CS_BK At that time, control M A and M D The switch is turned on, thus initiating the conduction phase of the buck mode, which can be called the buck phase (AD), and simultaneously activating the T in the conduction time generator. ON Timer. After the timer has been running for a certain period of time, M... D Switch off, M C The switching on, entering the boost mode, is called the boost phase (AC). When the error voltage V... EA The voltage V less than the peak current CS_BT At that time, M C Switch off, M D The switch is turned back on, the converter enters the boost shutdown phase, and the T in the shutdown time generator is activated. OFF Timer. At this point, after the timer restarts, M... A Switch off, M B The switch is turned on, entering the step-down shutdown phase. This cycle will occur at V. EA Reaching V again CS_BK This process continues to repeat to ensure that the converter can adjust the output in real time according to the load and input conditions.

[0131] The converter proposed in this embodiment of the invention also introduces a pause phase—section BC—to further optimize the converter's operation. When the load current I... L Less than zero current detection threshold I ZCD At that time, the system will automatically activate the pause phase, which will remain until V. EA Greater than V again CS_BK At this point, the converter resumes normal operation, ensuring that it remains stable even under conditions of significant load changes or momentary low load.

[0132] A schematic diagram of a wide-input buck-boost switching power supply converter provided in this embodiment of the invention is shown below. Figure 2 As shown, it can be seen from Figure 2 As can be seen, this converter employs dual feedback loop control. The outer voltage loop ensures the DC accuracy of the output voltage, while the inner current loop improves the converter's transient response performance. All control circuits and power switches are integrated within the chip to reduce reliance on external components and optimize system integration.

[0133] The loop module is the core of the converter's control system, primarily responsible for the precise regulation of current and voltage. This loop module may include: a current sampling circuit for sampling the current signal and providing accurate current feedback; an error amplification module for amplifying the error signal between the feedback output voltage signal and the reference voltage for subsequent adjustments; a comparator array responsible for adjusting the on and off times of the power switches to control voltage and current stability; and on-time and off-time generators that achieve dynamic control by adjusting the on and off times of the switching transistors to ensure stable output voltage.

[0134] This loop module adaptively adjusts the on / off time of the corresponding power switches to maintain the preset output voltage and improve transient response speed. The mode selection module is responsible for adjusting the input voltage V. IN With output voltage V OUT The module uses the difference in current to determine and select the correct operating mode. It also dynamically manages the operating status of each module through output signals, thereby reducing the static power consumption of the control circuit and improving the converter's efficiency. The Zero Current Detector (ZCD) circuit detects the zero-crossing point of the current to determine whether to enter light load mode. When the load current is low, the converter automatically enters pulse frequency modulation (PFM) after detection by the zero-crossing circuit, thereby reducing the switching frequency, minimizing switching losses, and achieving high efficiency. By dynamically switching the modulation method, the converter can reduce the switching frequency under light load conditions, achieving higher efficiency.

[0135] The schematic diagram of the state and working mode of the converter provided in the embodiments of the present invention is as follows: Figure 3 As shown, when the error voltage V output by the error amplifier... EA Above the voltage drop comparison threshold V CS_BK At that time, the switching transistor M A With M D When the circuit is turned on, the system enters the buck enable phase (AD), and the on-time timer T is started simultaneously. ON After the timer expires, the switching transistor M... D Turn-off, switching transistor M CWhen V is turned on, the system switches to the boost enable phase (AC). EA Below the boost comparison threshold V CS_BT At that time, the switching transistor M C Turn off and switch M D When the circuit is turned on, the system enters the boost shutdown phase and simultaneously starts the shutdown timer T. OFF After the timer is reset, the switching transistor M... A Turn-off, switching transistor M B When the circuit is turned on, the system enters the buck shutdown phase. This cycle occurs at V... EA Reaching V again CS_BK This process is repeated. If the load current I... L Below zero current detection threshold I ZCD The system will enter a pause phase (BC) until V. EA Higher than V CS_BK Then it resumes its normal working cycle.

[0136] The waveform diagrams of the converter operating under different input voltages provided in this embodiment of the invention are as follows: Figure 4 As shown, it highlights the seamless switching process between buck mode (BK), buck-boost mode (BB), and boost mode (BT). The trapezoidal current waveform design proposed in this embodiment of the invention keeps the average inductor current similar in different operating modes, thereby effectively suppressing inductor current spikes that occur during mode transitions and reducing output voltage fluctuations.

[0137] In buck-boost mode, the voltage conversion ratio can be expressed by the following formula:

[0138] ;

[0139] in, and They represent the switching transistors M and M respectively. A On-time T ON_A and switching transistor M C On-time T ON_C With switching period T S The ratio of . This relationship shows that the boost / buck mode can provide both boost and buck functions simultaneously.

[0140] The relationship between load current, output current, and average inductor current in buck, boost, and buck-boost modes is given by the following expression:

[0141] ;

[0142] ;

[0143] ;

[0144] Combination Figure 4 As shown in the waveforms and the above formula analysis, in buck-boost mode, due to the doubling of the switching cycle and the switching transistor M... C Operating at minimum conduction time T ON_C_MIN The resulting duty cycle ensures that the average inductor current closely matches the current in buck mode. Furthermore, under the same conversion ratio, a longer cycle length T... S This results in a lower average current in this mode compared to the boost mode.

[0145] Furthermore, the four-stage T adopted by the system S The structure (in sequence, AC, AD, BD, AD phases) is matched with the switching transistor M. B Minimum conduction time T ON_B_MIN (In this embodiment, it can be set to 100ns), which can ensure that the deviation of the average inductor current during the mode switching process is controlled within a very small range, thereby achieving seamless switching between various working modes.

[0146] A schematic diagram of the on / off time generation circuit of the converter provided in this embodiment of the invention is shown below. Figure 5 As shown, in boost mode, the operational amplifier (OPA) and comparator (COMP) receive the input signal K1V respectively. OUT and K2V IN This generates the off-time (TOFF); in buck mode, its input signal switches to K1V. IN and K2V OUT Used to generate conduction time (T) ON ).

[0147] The buck mode uses constant on-time control, and its expression is:

[0148] ;

[0149] The resulting buck mode switching cycle is:

[0150] ;

[0151] The boost mode uses constant off-time control, and its expression is:

[0152] ;

[0153] The resulting boost mode switching cycle is:

[0154] ;

[0155] Where K1 and K2 are the input voltages V IN and output voltage VOUT The proportionality coefficient. This adaptive constant on / off time scheme can maintain a constant switching frequency determined only by K1, K2, resistor R and capacitor C, thereby significantly reducing the electromagnetic interference (EMI) effect at different conversion ratios.

[0156] For the buck-boost mode, according to the volt-second balance principle, we can obtain:

[0157] ;

[0158] when When, it is simplified to:

[0159] ;

[0160] Therefore, we can conclude that:

[0161] ;

[0162] It can be seen that T ON_C With V IN / V OUT The ratio decreases as V increases. IN ≈V OUT At that time, the switching frequency F in buck-boost mode SW It is about half the voltage of either the buck or boost mode.

[0163] The control logic diagram of the logic control circuit in the converter provided in this embodiment of the invention is as follows: Figure 6 As shown, the control logic includes a falling-edge sampling circuit, an RS flip-flop, and basic logic gates. CS_BK and V CS_BT Signal and V EA CMP generated after comparison BK and CMP BT Pulse, used to trigger T ON / T OFF The generator then produces T. ON_BK and T OFF_BT These signals are processed by the control logic to generate the enable signal EN. TON and EN TOFF Ultimately, through T ON_BK T OFF_BT EN TON and EN TOFF The combination of these factors generates the gate drive signal T for the power switch. ON_A and T ON_D .

[0164] Timing diagrams of the converter in different modes, such as Figures 7a-7c As shown, where Figure 7a This is the timing diagram of the signal corresponding to Boost mode. When M...C The tube performs peak current sampling, V CS_BT Greater than V EA At that time, CMP BT Generate a pulse, thereby triggering T OFF The timer's duration is in segments A and D. After the timer finishes, segments A and C are activated. To prevent accidental activation, T... ON_BK CMP BK At this time, all are controlled by EN. BT Signal shielding is 0 for all values. At this time, M A Pipe is always open, M B Guan Changguan, M C With M D The tubes alternately conduct. Figure 7b This is the timing diagram for the signals corresponding to Buck mode. When M... B The tube performs valley current sampling, V CS_BK Less than V EA At that time, CMP BK Generate a pulse, thereby triggering T ON The timer has an AD segment for the duration of the countdown. After the countdown ends, the BD segment begins. To prevent accidental activation, T... ON_BT CMP BT At this time, all are controlled by EN. BK Signal shielding is 0 for all values. At this time, M D Pipe is always open, M C Guan Changguan, M A With M B The tubes alternately conduct. Figure 7c This is the timing diagram of the signal corresponding to Buck-Boost mode, V CS_BK and V CS_BT Signal and V EA CMP generated after comparison BK and CMP BT Pulse, used to trigger T ON / T OFF The generator then produces T. ON_BK and T OFF_BT These signals are processed by the control logic to generate the enable signal EN. TON and EN TOFF Ultimately, through T ON_BK T OFF_BT EN TON and EN TOFF The combination of these factors generates the gate drive signal T for the power switch. ON_A T ON_B T ON_C T ON_D At this time, M A -M D The tubes are alternately switched on.

[0165] Compared to traditional mode selection schemes based on fixed hysteresis comparators, the dynamic mode selection circuit proposed in this embodiment of the invention significantly improves the stability and adaptability of the buck-boost converter during mode switching by introducing duty cycle detection and an adjustable hysteresis window. Its circuit structure is as follows: Figure 8 shown. EN BK EN BB and EN BT The signals serve as indicators for the three operating modes: buck, buck-boost, and boost, and also participate in enabling the control module to reduce system power consumption and prevent false triggering. The specific workflow is as follows:

[0166] When the input voltage V IN When the input voltage starts to rise from a low level, the converter initially operates in boost mode; when V IN >A2V OUT At that time, the system switches to buck-boost mode; as V IN Continue to rise, when V IN B2V OUT When V is high, the system enters buck mode. Conversely, when V is high... IN When the voltage starts to drop from a high input voltage, at V IN <B2V OUT The system switches to buck-boost mode; as V IN Further reduction, when V IN <A1V OUT When the voltage reaches a certain level, the system enters boost mode. In this embodiment of the invention, A1=0.8, A2=0.85, B1=1.2, and B2=1.3 are set. This design enables the system to accurately determine the switching conditions between boost / buck / boost mode and buck / buck / boost mode.

[0167] The converter proposed in this invention employs a hybrid current-mode constant on / off time control strategy, enabling efficient and stable precise regulation of the output voltage over a wide input voltage range, exhibiting excellent input adaptability. Adaptive constant on-time control is used in buck mode, and adaptive constant off-time control is used in boost mode, ensuring optimized dynamic response and stability under different conversion conditions. In buck-boost modes, a pseudo-fixed frequency modulation reduction mechanism is used to improve system efficiency while maintaining output regulation accuracy and effectively suppressing electromagnetic interference. By introducing a light-load control strategy combining hybrid pulse frequency modulation and pulse cross-cycle modulation, and activating a pause phase under light-load conditions, the conversion efficiency under light-load conditions is significantly improved. The control strategy adopted in this invention improves stability and transient response; the buck-boost mode reduces the switching frequency, increasing efficiency; pseudo-fixed switching frequency can be achieved in all three modes, improving EMI; the introduction of the BC stage reduces diode conduction losses and improves light-load efficiency.

[0168] Secondly, corresponding to the above-described converter embodiments, this invention also provides a wide-input buck-boost switching power supply conversion control method, such as... Figure 9 As shown, when applied to any of the wide-input buck-boost switching power converters described in the first aspect, the control method may include:

[0169] S1, the output voltage signal is obtained by using the feedback resistor network in the error amplifier module, and the output voltage signal is compared with the reference voltage to output the error voltage;

[0170] S2 utilizes a current sampling circuit to collect inductor current in real time and generate a corresponding current detection signal;

[0171] S3 uses a comparator to compare the current detection signal with the error voltage, triggering the corresponding on-time generation circuit and off-time generation circuit.

[0172] S4, the on-time generator, triggered by the corresponding comparator, counts the on-time based on the input voltage and output voltage, and outputs an on-time control signal;

[0173] S5, the turn-off time generator, triggered by the corresponding comparator, counts the turn-off time based on the input voltage and output voltage, and outputs a turn-off time control signal;

[0174] S6 utilizes a dynamic mode selection circuit to output a corresponding mode selection signal based on the relationship between the input voltage and the output voltage.

[0175] S7 generates drive signals corresponding to different modes through logic control circuits based on mode selection signal, on-time control signal and off-time control signal; at the same time, it detects the zero-crossing point of the current of the load inductor in the four power switch modules through zero-crossing detection circuit to determine whether the converter enters light load mode. In light load mode, a pause phase is introduced to make the converter enter pulse cross-cycle modulation mode to reduce the frequency and loss of the converter.

[0176] S8 controls the output conversion voltage of the four power switching transistor modules according to the drive signals corresponding to different modes.

[0177] Understandably, the detailed process of step S1 can be found in the description of the working principle of the error amplification module in the first aspect; the detailed process of step S2 can be found in the description of the working principle of the current sampling circuit in the first aspect; the detailed process of step S3 can be found in the description of the working principle of the comparator in the first aspect; the detailed process of step S4 can be found in the description of the working principle of the on-time generator in the first aspect; the detailed process of step S5 can be found in the description of the working principle of the off-time generator in the first aspect; the detailed process of step S6 can be found in the description of the working principle of the dynamic mode selection circuit in the first aspect; the detailed process of step S7 can be found in the description of the working principle of the logic control circuit in the first aspect; and the detailed process of step S8 can be found in the description of the working principle of the four-way power switch module in the first aspect. Further details will not be provided here.

[0178] The converter proposed in this invention optimizes its efficiency and performance by introducing adaptive constant on-time and off-time generators. By precisely adjusting the on-time and off-time of the switches, it achieves a smooth transition between different operating modes, thereby improving the converter's stability and efficiency. It can efficiently and stably achieve precise adjustment of the output voltage over a wide input voltage range, exhibiting excellent input adaptability. Adaptive constant on-time control is used in buck mode, and adaptive constant off-time control is used in boost mode, ensuring optimized dynamic response and stability under different conversion conditions. Furthermore, in buck-boost mode, a pseudo-fixed frequency reduction modulation mechanism is used to improve system efficiency while ensuring output regulation accuracy and effectively suppressing electromagnetic interference. By introducing a light-load control strategy combining hybrid pulse frequency modulation and pulse cross-cycle modulation, and activating a pause phase under light-load conditions, the conversion efficiency of the system under light-load conditions is significantly improved.

[0179] It should be noted that, in the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0180] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the method embodiments are basically similar to the converter embodiments, so the description is relatively simple; relevant parts can be referred to the description of the converter embodiments.

[0181] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A wide-input buck-boost switching power supply converter, characterized in that, include: The circuit includes an error amplifier module, a current sampling circuit, a comparator array, an on-time generator, an off-time generator, a dynamic mode selection circuit, a logic control circuit, a zero-crossing detection circuit, and a four-channel power switch module; among which, The error amplification module uses a type II compensation network to obtain the output voltage signal through its own feedback resistor network, and then outputs the error voltage after comparing the output voltage signal with the reference voltage. The current sampling circuit collects the corresponding current in the four power switching transistor modules in real time and generates the corresponding current detection signal. The comparator triggers the corresponding on-time generator and off-time generator by comparing the current detection signal with the error voltage. The on-time generator, triggered by the corresponding comparator, counts the on-time based on the input voltage and the output voltage, and outputs an on-time control signal. The shutdown time generator, triggered by the corresponding comparator, counts the shutdown time based on the input voltage and the output voltage, and outputs a shutdown time control signal. The dynamic mode selection circuit outputs a corresponding mode selection signal based on the relationship between the input voltage and the output voltage. The logic control circuit generates drive signals corresponding to different modes based on the mode selection signal, the on-time control signal, and the off-time control signal. At the same time, it detects the zero-crossing point of the current in the load inductor in the four power switch modules through the zero-crossing detection circuit to determine whether the converter enters the light load mode. In the light load mode, a pause phase is introduced to enable the converter to perform pulse cross-cycle modulation in order to reduce the frequency and loss of the converter. The four-channel power switching module outputs the corresponding conversion voltage according to the drive signal corresponding to different modes.

2. The wide input buck-boost switching power supply converter according to claim 1, characterized in that, The error amplification module includes: The system consists of a feedback resistor network, an error amplifier, and a Type II compensation network; among which, The input terminal of the feedback resistor network is connected to the output voltage signal, and the output terminal is connected to the inverting input terminal of the error amplifier. The non-inverting input terminal of the error amplifier is connected to a reference voltage, and the output terminal serves as the output terminal of the error amplification module. The input terminal of the type II compensation network is connected to the output terminal of the feedback resistor network, and the output terminal is connected to the output terminal of the error amplifier.

3. The wide input buck-boost switching power supply converter according to claim 1, characterized in that, The current detection signal includes valley current and peak current; the comparator array triggers the corresponding on-time generator and off-time generator by comparing the current detection signal with the error voltage, including: The first comparator in the comparator array corresponds to the voltage V of the valley current. CS_BK With error voltage V EA Comparison, when V EA Greater than V CS_BK At that time, the first trigger signal CMP is output. BK This triggers the on-time generator; The second comparator in the comparator array corresponds to the voltage V of the peak current. CS_BT With error voltage V EA When comparing, when V EA Less than V CS_BT At that time, the second trigger signal CMP is output. BT This triggers the shutdown time generator.

4. A wide-input buck-boost switching power supply converter according to claim 3, characterized in that, The conduction time generator, triggered by the corresponding comparator, times the conduction time based on the input voltage and output voltage, and outputs a conduction time control signal, including: The conduction time generator, triggered by the first comparator, when the input voltage V... IN Greater than the output voltage V OUT At that time, the conduction time generation circuit in the conduction time generator is based on the input voltage V. IN Output voltage V OUT and the first trigger signal CMP BK Output conduction signal T ON_BK The RS flip-flop in the conduction time generator outputs the conduction time control signal PWM. BK .

5. A wide-input buck-boost switching power supply converter according to claim 3, characterized in that, The turn-off time generator, triggered by a corresponding comparator, times the turn-off time based on the input voltage and output voltage, and outputs a turn-off time control signal, including: The off-time generator, triggered by the second comparator, when the input voltage V... IN Less than the output voltage V OUT At that time, the turn-off time generation circuit in the turn-off time generator is based on the input voltage V. IN Output voltage V OUT Second trigger signal CMP BT Output off signal T OFF_BT The RS flip-flop in the turn-off time generator outputs the turn-off time control signal PWM. BT .

6. A wide-input buck-boost switching power supply converter according to claim 1, characterized in that, The dynamic mode selection circuit outputs a corresponding mode selection signal based on the relationship between the input voltage and the output voltage, including: When the input voltage V IN Greater than the output voltage V OUT At that time, the dynamic mode selection circuit will output a high-level enable signal EN. BK Low-level enable signal EN BB and the low-level enable signal EN BT Output as the mode selection signal corresponding to Buck mode; When the input voltage V IN Less than the output voltage V OUT At that time, the dynamic mode selection circuit will output a high-level enable signal EN. BT Low-level enable signal EN BB and the low-level enable signal EN BK Output as the mode selection signal corresponding to Boost mode; When the input voltage V IN With output voltage V OUT When the difference is within a preset range, the dynamic mode selection circuit will send a high-level enable signal EN. BB Low-level enable signal EN BK and the low-level enable signal EN BT This output serves as the mode selection signal for the Buck-Boost mode.

7. A wide-input buck-boost switching power supply converter according to claim 6, characterized in that, The logic control circuit generates drive signals corresponding to different modes based on the mode selection signal, the on-time control signal, and the off-time control signal, including: The logic control circuit outputs an adaptive constant on-time control signal as the driving signal corresponding to the Buck mode, based on the mode selection signal and the on-time control signal corresponding to the Buck mode. Based on the mode selection signal and turn-off time control signal corresponding to the Boost mode, an adaptive constant turn-off time control signal is output as the driving signal corresponding to the Boost mode. Based on the mode selection signal, on-time control signal, and off-time control signal corresponding to the Buck-Boost mode, a quasi-fixed frequency de-modulated signal is output as the driving signal corresponding to the Buck-Boost mode.

8. A wide-input buck-boost switching power supply converter according to claim 7, characterized in that, The four-channel power switching module outputs corresponding conversion voltages based on the drive signals corresponding to different modes, including: When the drive signal is the drive signal corresponding to Buck mode, the error voltage V EA The voltage V corresponding to the peak current is greater than the valley current. CS_BK At that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After the preset conduction time has elapsed, the conduction time generator controls its own switching transistor M to turn on. A Close, switch transistor M B and switching transistor M D When the circuit is turned on, the corresponding conversion voltage is output. When the drive signal is the drive signal corresponding to Boost mode, the error voltage V EA The voltage V less than the peak current CS_BT At that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After a preset turn-off time, the turn-on and turn-off time generator controls its own switching transistor M. A Close, switch transistor M C When the circuit is turned on, the corresponding conversion voltage is output. When the drive signal is the drive signal corresponding to Buck-Boost mode, the error voltage V EA The voltage V corresponding to the peak current is greater than the valley current. CS_BK At that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After the preset conduction time has elapsed, the conduction time generator controls its own switching transistor M to turn on. A On / off transistor M C On; when the error voltage V EA The voltage V less than the peak current CS_BT At that time, the four-channel power switching module controls its own switching transistor M. A and switching transistor M D After a preset turn-off time, the turn-on and turn-off time generator controls its own switching transistor M. A Close, switch transistor M B and switching transistor M D When the circuit is turned on, the corresponding conversion voltage is output.

9. A wide-input buck-boost switching power supply converter according to claim 1, characterized in that, The zero-crossing detection circuit detects the zero-crossing point of the current in the load inductor of the four power switching transistor module to determine whether the converter enters light load mode. In light load mode, a pause phase is introduced, enabling the converter to perform pulse cross-cycle modulation, including: When the zero-crossing detection circuit detects that the load current of the load inductor in the four-channel power switch module is less than the preset zero-current detection threshold, the converter enters a light-load mode, activates the pause phase, and performs pulse cross-cycle modulation. The pause phase will be maintained until the error voltage V. EA The voltage V corresponding to the peak current is greater than the valley current. CS_BK Afterwards, the control converter resumes normal operation.

10. A wide-input buck-boost switching power supply conversion control method, characterized in that, The control method, applied to the wide input buck-boost switching power converter as described in any one of claims 1-9, comprises: The output voltage signal is obtained by using the feedback resistor network in the error amplifier module, and the error voltage is output after comparing the output voltage signal with the reference voltage. The current sampling circuit is used to collect the inductor current in real time and generate the corresponding current detection signal. A comparator is used to compare the current detection signal with the error voltage, triggering the corresponding on-time generation circuit and off-time generation circuit. When triggered by the corresponding comparator, the on-time generator calculates the on-time based on the input and output voltages and outputs an on-time control signal. When triggered by the corresponding comparator, the shutdown time generator calculates the shutdown time based on the input voltage and output voltage, and outputs a shutdown time control signal. A dynamic mode selection circuit is used to output a corresponding mode selection signal based on the relationship between the input voltage and the output voltage. Based on the mode selection signal, on-time control signal, and off-time control signal, the logic control circuit generates drive signals corresponding to different modes. At the same time, the zero-crossing detection circuit detects the zero-crossing point of the current in the load inductor in the four power switch modules to determine whether the converter enters the light load mode. In the light load mode, a pause phase is introduced to make the converter enter the pulse cross-cycle modulation mode to reduce the converter's frequency and loss. Based on the drive signals corresponding to different modes, the four power switching transistor modules are controlled to output the corresponding conversion voltages.

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