Transient enhancement multiphase Buck converter and control method thereof

Abstract

The invention relates to a transient enhanced multi-phase Buck converter and a control method thereof, and the method comprises the steps: continuously monitoring and outputting a voltage reduction signal through a capacitance current sampling module, calculating a to-be-judged voltage signal, and outputting a high-level judgment signal when the to-be-judged voltage signal is greater than a reference voltage VTH1; after receiving the signal, the phase control module forcibly outputs logic control signals which are all high levels to the self-adaptive conduction time generation module; the multi-phase current conversion module synchronously conducts all single-phase Buck conversion circuits in the multi-phase current conversion module accordingly, so that the single-phase Buck conversion circuits simultaneously work to output the maximum current, and severe fluctuation of the output voltage is rapidly inhibited; and when the full-phase forced working mode is maintained until the voltage signal to be judged corresponding to the new voltage reduction signal is smaller than the reference voltage VTH2 again, the transient is relieved, and the system is automatically switched back to the conventional minimum current phase interleaving control mode. According to the scheme, the problem of response lag of a traditional multi-phase Buck under extreme load transient can be effectively solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of switching power supply control, and in particular relates to a transient enhanced multi-phase Buck converter and a control method thereof. Background Art

[0002] Multiphase Buck converters, with their high efficiency, high power density, and excellent ripple suppression, have become a mainstream core power architecture in modern high-performance computing, communications equipment, and data centers. Their core advantage lies in their ability to distribute the total load current across multiple interleaved parallel power stages (each called a "phase"), significantly reducing input and output capacitor current stress and system ripple while improving overall efficiency.

[0003] In multi-phase Buck converter applications, fast transient response is key to ensuring power system stability. Traditional solutions typically rely on the bandwidth of the feedback loop to adjust the current distribution between phases. However, when the load current suddenly changes, the output voltage may still fluctuate significantly due to the limited loop response speed. Existing technologies often use dynamic phase expansion or peak current control to improve transient performance, but these methods still rely on loop regulation and have difficulty achieving precise coordination of multi-phase currents in a very short time. In addition, conventional current balancing strategies are usually based on steady-state optimization and cannot quickly determine the optimal current distribution method during transient processes, resulting in limited dynamic performance. Therefore, there is an urgent need for a multi-phase control strategy that can quickly respond to sudden load changes and is not constrained by loop bandwidth. Once a transient condition is detected, the enhancement mechanism is immediately activated, thereby significantly shortening the adjustment time and optimizing dynamic performance. Summary of the Invention

[0004] To address the above-mentioned problems in the prior art, the present invention provides a transient enhanced multi-phase Buck converter and a control method thereof. The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0005] In the first aspect, the present invention provides a transient enhanced multi-phase Buck converter, comprising: an adaptive on-time generation module, a multi-phase current conversion module, a current comparison module, a phase control module, a capacitor current sampling module and a main circuit; wherein: the capacitor current sampling module is used to collect the current time-staggered and superimposed step-down signal output by the multi-phase current conversion module in real time, and use the step-down signal to calculate the voltage signal to be judged, and generate a corresponding judgment signal based on the judgment result of whether the voltage signal to be judged is greater than a first threshold voltage, wherein when the voltage signal to be judged is greater than the first threshold voltage, the judgment signal is a high level; the current comparison module is used to obtain N current values ​​corresponding to the N output terminals of the multi-phase current conversion module, and compare the N current values ​​to obtain a comparison result, And the comparison result is sent to the phase control module, and the comparison result is used to reflect the minimum current value among the current N current values, and the channel position where the minimum current value is located; the phase control module is used to generate corresponding multiple logic control signals based on the judgment signal, the comparison result and the voltage signal sent by the main circuit; wherein, when the judgment signal is high, the corresponding logic control signals are all high-level signals; the adaptive conduction time generation module is used to respond to the multiple logic control signals and control the multi-phase current conversion module to generate a new step-down signal, wherein, when the logic control signals are all high-level signals, all single-phase Buck conversion circuits in the multi-phase current conversion module are turned on until the voltage signal to be judged corresponding to the new step-down signal is less than the second threshold voltage.

[0006] Preferably, the multi-phase current conversion module includes N parallel single-phase Buck conversion circuits; the input end of each single-phase Buck conversion circuit is connected to the input end of the multi-phase current conversion module, the input end of the multi-phase current conversion module is connected to the external power supply VIN, the first output end of each single-phase Buck conversion circuit is connected to the output end of the multi-phase current conversion module, the second output end of each single-phase Buck conversion circuit is connected to the first to N input ends of the current comparison module, and the output end of the multi-phase current conversion module outputs the step-down signal; the input end of the capacitor current sampling module is connected to the output end of the multi-phase current conversion module, the first output end is connected to the first input end of the phase control module, and the second output end is connected to the first input end of the main circuit; the second input end of the main circuit is connected to the voltage division signal V FBThe first to Nth input terminals of the current comparison module are respectively connected to the second output terminals of each single-phase BUCK module, and the first to Nth output terminals are respectively connected to the second to N+1th input terminals of the phase control module; the output terminal of the main circuit is connected to the N+2th input terminal of the phase control module; the first to Nth output terminals of the phase control module are respectively connected to the first to Nth input terminals of the adaptive on-time generation module; the first to Nth output terminals of the adaptive on-time generation module are respectively connected to the control terminal of a single-phase Buck conversion circuit in the multi-phase current conversion module.

[0007] Preferably, the first threshold voltage is a reference voltage V TH1 , the second threshold voltage is the reference voltage V TH2 , the reference voltage V TH1 is greater than the reference voltage V TH2 The first input terminal of the capacitor current sampler is connected to the output terminal of the multi-phase current conversion module, and the second input terminal is connected to the common mode voltage V CM , the output end is connected to the first input end of the transient detector and the first input end of the reverse amplifier respectively; the second input end of the transient detector is connected to the reference voltage V TH1 , the third input terminal is connected to the reference voltage V TH2 , the output end is connected to the first input end of the phase control module; the second input end of the reverse amplifier is connected to the common mode voltage V CM , the output end is connected to the second end of the first adder; the capacitor current sampler is used to obtain the buck signal and calculate the voltage signal to be judged V according to the buck signal CCS The transient detector is used to determine the voltage signal V CCS Is it greater than the reference voltage V TH1 If so, output a high level state judgment signal, if it is less than the reference voltage V TH2 , outputs a judgment signal of a low level state; the reverse amplifier is used to output a judgment signal of a low level state based on the common mode voltage V CM , the voltage signal to be judged V CCS Perform reverse amplification processing to obtain a reverse amplified signal.

[0008] Preferably, the capacitor current sampler includes: a capacitor C1, a resistor R1, a resistor R SEN and a transimpedance amplifier EA1; wherein one end of the capacitor C1 is connected to the first output end of the N phase current channels, and the other end is connected to one end of the resistor R1; the other end of the resistor R1 is respectively connected to the negative electrode of the transimpedance amplifier EA1 and the resistor R SENThe positive electrode of the transimpedance amplifier EA1 is connected to the common mode voltage V CM The output end of the transimpedance amplifier EA1 and the resistor R SEN The other end serves as the output end of the capacitor current sampler.

[0009] Preferably, the reverse amplifier comprises: a resistor R A , resistor R B and operational amplifier EA2; the resistor R A One end is connected to the output end of the capacitor current sampler, and the other end is connected to the negative electrode of the operational amplifier EA2 and the resistor R B One end of the resistor R B The other end is connected to the output end of the operational amplifier EA2, and the positive electrode of the operational amplifier EA2 is connected to the common mode voltage V CM , the output end of the operational amplifier EA2 is connected to the first input end of the first adder.

[0010] Preferably, the transient detector comprises: a comparator CMP1, a comparator CMP2 and an RS trigger; the negative electrode of the comparator CMP1 is connected to the reference voltage V TH1 , the positive electrode is connected to the output end of the capacitor current sampler, and the output end is connected to the reset end of the RS trigger; the positive electrode of the comparator CMP2 is connected to the reference voltage V TH2 , the negative electrode is connected to the output end of the capacitor current sampler, and the output end is connected to the set end of the RS trigger; the output end of the RS trigger is connected to the second input end of the phase control module.

[0011] Preferably, the main circuit includes: an error amplifier, a comparator, a first adder, a second adder and a sawtooth wave generator; wherein: the input end of the error amplifier and the first end of the first adder are both connected to the voltage-divided signal V FB The output end of the error amplifier is connected to the first end of the second adder, the output end of the sawtooth wave generator is connected to the second end of the second adder; the second end of the first adder is connected to the second output end of the capacitor current sampling module; the output end of the first adder is connected to the positive electrode of the comparator, the output end of the second adder is connected to the negative electrode of the comparator, and the output end of the comparator is respectively connected to the input end of the sawtooth wave generator and the N+2th input end of the phase control module.

[0012] Preferably, the external load includes: a feedback resistor R FB1 , feedback resistor R FB2 , load capacitance CL and load resistance RL; wherein, the feedback resistor RFB1 One end of the load capacitor CL and one end of the load resistor RL are all connected to the output end of the multi-phase current conversion module; the feedback resistor R FB1 The other end of the feedback resistor R FB2 The feedback resistor R FB2 The other end of the load capacitor CL and the other end of the load resistor RL are grounded.

[0013] Preferably, it is characterized in that the voltage signal to be judged V CCS The calculation expression satisfies:

[0014] V CCS =V CM -i SEN R SEN ;

[0015] Among them, V CM is the common-mode voltage, R SEN is the resistor connected across the transimpedance amplifier EA1, i SEN is the current flowing through the resistor R SEN of current.

[0016] In a second aspect, the present invention further provides a control method for a transient enhanced multi-phase Buck converter, which is used to control the transient enhanced multi-phase Buck converter described in the first aspect above; the control method comprises: real-time acquisition of the current temporally interleaved step-down signal output by the multi-phase current conversion module, and calculation of the voltage signal to be judged using the step-down signal, and generating a corresponding judgment signal based on the judgment result of whether the voltage signal to be judged is greater than a first threshold voltage, wherein when the voltage signal to be judged is greater than the first threshold voltage, the judgment signal is a high level; obtaining N current values ​​corresponding to the N output terminals of the multi-phase current conversion module, and comparing the N current values ​​to obtain a comparison result, and The comparison result is sent to the phase control module, and the comparison result is used to reflect the minimum current value among the current N current values, as well as the channel position where the minimum current value is located; based on the judgment signal, the comparison result and the voltage signal sent by the main circuit, a corresponding plurality of logic control signals are generated; wherein, when the judgment signal is at a high level, the corresponding logic control signals are all high-level signals; in response to the plurality of logic control signals, the multi-phase current conversion module is controlled to generate a new step-down signal, wherein, when the logic control signals are all high-level signals, all single-phase Buck conversion circuits in the multi-phase current conversion module are turned on until the voltage signal to be judged corresponding to the new step-down signal is less than the second threshold voltage.

[0017] Compared with the prior art, the present invention has the following beneficial effects: in response to the inherent response bottleneck problem of traditional multi-phase Buck converters when facing sudden, high-slope load transient changes, the present invention provides a transient-enhanced multi-phase Buck converter and its control method. The transient-enhanced multi-phase Buck converter calculates the voltage signal to be judged that represents the dynamic load capacitance in real time through a capacitor current sampling module and compares it with a preset threshold, which can sensitively and accurately detect severe load transients; when it is detected that the voltage signal to be judged exceeds the threshold range, the phase control module is forced to output a full high-level logic control signal, triggering the adaptive conduction time generation module to synchronously turn on all single-phase Buck conversion circuits, instantly releasing the system's maximum current capacity to quickly compensate for the load mutation energy; after the system recovers stability, it automatically switches back to the conventional high-efficiency control mode based on the minimum current phase preferential conduction. This design maintains the inherent low ripple and high-efficiency steady-state advantages of the multi-phase Buck system while effectively solving the transient voltage fluctuation problem caused by response lag and decision deviation in the traditional solution, significantly improving the dynamic response speed and output voltage stability of the converter under extreme load jumps. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 1 is a circuit connection diagram of a transient enhanced multi-phase Buck converter provided by an embodiment of the present invention;

[0019] Figure 2 This is an example diagram of signal waveform changes at the current comparison module and the phase control module using two single-phase Buck conversion circuits as examples provided by an embodiment of the present invention;

[0020] Figure 3 1 is a circuit connection diagram of a capacitor current sampling module provided in an embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of the waveform changes of the positive and negative terminals and the output terminal of the main circuit comparator provided by an embodiment of the present invention;

[0022] Figure 5 Is the capacitor current I output by the current conversion module in the single-phase Buck converter c , inductor current I L and load current I load Schematic diagram of the relationship waveform change;

[0023] Figure 6 This is an example diagram of changes in inductor current and output voltage after a single-phase Buck converter according to an embodiment of the present invention performs transient enhancement;

[0024] Figure 7 1 is a simulation diagram of a transient enhanced multi-phase Buck converter provided by an embodiment of the present invention;

[0025] Figure 8 4 is another simulation schematic diagram of the transient enhanced multi-phase Buck converter provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below with reference to specific examples, but the embodiments of the present invention are not limited thereto.

[0027] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0028] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

[0029] Although the present invention is described herein in conjunction with various embodiments, in the process of implementing the claimed invention, those skilled in the art can understand and implement other variations of the disclosed embodiments by reviewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude multiple situations. A single processor or other unit can implement several functions listed in the claims. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0030] A transient enhanced multi-phase Buck converter and a control method thereof provided by the present invention are now described in detail with reference to the accompanying drawings. Figure 1 FIG1 is a circuit connection diagram of a transient enhanced multi-phase Buck converter provided by an embodiment of the present invention. In a possible application scenario, the transient enhanced multi-phase Buck converter provided by the present invention can be integrated into a circuit chip.

[0031] The transient enhanced multi-phase Buck converter includes: an adaptive on-time generation module, a multi-phase current conversion module, a current comparison module, a phase control module, a capacitor current sampling module and a main circuit; wherein: the capacitor current sampling module is used to collect the current time-staggered and superimposed step-down signals output by the multi-phase current conversion module in real time, and use the step-down signals to calculate the voltage signal to be judged, and generate a corresponding judgment signal based on the judgment result of whether the voltage signal to be judged falls within a preset threshold range; the current comparison module is used to obtain N current values ​​corresponding to the N output terminals of the multi-phase current conversion module, compare the N current values, obtain a comparison result, and send the comparison result to the phase control module. The comparison result is used to reflect the minimum current value among the current N current values, as well as the channel position where the minimum current value is located; the phase control module is used to generate corresponding multiple logic control signals based on the judgment signal, the comparison result and the voltage signal sent by the main circuit; wherein, when the judgment signal is high, the corresponding logic control signals are all high-level signals; the adaptive on-time generation module is used to respond to multiple logic control signals and control the multi-phase current conversion module to generate a new step-down signal, wherein, when all the logic control signals are high-level signals, all single-phase Buck conversion circuits in the multi-phase current conversion module are turned on until the voltage signal to be judged corresponding to the new step-down signal falls into the preset threshold range.

[0032] Here, the multi-phase current conversion module includes N parallel single-phase Buck conversion circuits; the input end of each single-phase Buck conversion circuit is connected to the input end of the multi-phase current conversion module, the input end of the multi-phase current conversion module is connected to the external power supply VIN, the first output end of each single-phase Buck conversion circuit is connected to the output end of the multi-phase current conversion module, the second output end of each single-phase Buck conversion circuit is connected to the input section of the current comparison module, and the output end of the multi-phase current conversion module outputs a step-down signal; the input end of the capacitor current sampling module is connected to the output end of the multi-phase current conversion module, the first output end is connected to the first input end of the phase control module, and the second output end is connected to the first input end of the main circuit; the second input end of the main circuit is connected to the voltage division signal V FB The first to Nth input terminals of the current comparison module are respectively connected to the second output terminals of each single-phase buck circuit, and the first to Nth output terminals are respectively connected to the second to N+1th input terminals of the phase control module; the output terminal of the main circuit is connected to the N+2th input terminal of the phase control module; the first to Nth output terminals of the phase control module are respectively connected to the first to Nth input terminals of the adaptive on-time generation module; the first to Nth output terminals of the adaptive on-time generation module are respectively connected to the control terminal of a single-phase buck conversion circuit in the multi-phase current conversion module.

[0033] For example, the adaptive on-time generation module includes multiple adaptive on-time generators. For a multi-phase Buck converter, it is necessary to constantly detect the relative magnitude of the multi-phase currents to determine which phase to turn on. That is, the phase control module outputs a logic control signal Vctrl to the phase with the smallest current among the multi-phases. This circuit converts the current value I output by each single-phase Buck conversion circuit into L1 , I L2 ...I LN The current comparison module obtains the phase with the smallest current at this time and then transmits it to the phase control module. For example, if I L2 The current comparison module outputs D2 = 1, and the outputs D1, D3, ..., DN corresponding to the other single-phase Buck conversion circuits are all 0. Then, the phase control module outputs a high-level signal to the control module for generating I L2 The adaptive on-time generator of the single-phase Buck conversion circuit is configured, and the logic control signals received by the other adaptive on-time generators are all low level. Figure 2 This is an example diagram of the signal waveform changes at the current comparison module and the phase control module using two single-phase Buck conversion circuits as an example provided by the embodiment of the present invention. Figure 2 As shown, where V _det is the output result of the current comparison module, V _det When it is high, it means I L1 >I L2 , otherwise it represents I L1 L2 . V _det When it is high, Vctrl2 is high, V _det When it is low, Vctrl1 is high.

[0034] Here, the external load includes: feedback resistor R FB1 , feedback resistor R FB2 , load capacitance CL and load resistance RL; where the feedback resistor R FB1 One end of the load capacitor CL and one end of the load resistor RL are connected to the output end of the multi-phase current conversion module; the feedback resistor R FB1 The other end of the feedback resistor R FB2 One end of the first adder, the second input end of the first adder and the input end of the error amplifier are connected; the feedback resistor R FB2 The other end of , the other end of the load capacitor CL and the other end of the load resistor RL are grounded.

[0035] Figure 3 Schematic diagram of the circuit connection of the capacitor current sampling module provided by an embodiment of the present invention. Figure 4 Schematic diagram of the changes in the positive and negative terminals and output terminals of the main circuit comparator provided by the embodiment of the present invention.​ Figure 3 As shown, the threshold voltage is the reference voltage V TH1 The capacitor current sampling module includes: a capacitor current sampler, a transient detector and an inverting amplifier; the first input terminal of the capacitor current sampler is connected to the output terminal of the multi-phase current conversion module, and the second input terminal is connected to the common mode voltage V CM The output end is connected to the first input end of the transient detector and the first input end of the inverting amplifier respectively; the second input end of the transient detector is connected to the reference voltage V TH1 , the third input terminal is connected to the reference voltage V TH2 The output terminal is connected to the first input terminal of the phase control module, and the reference voltage V TH1 Greater than the reference voltage V TH2 ; The second input of the inverting amplifier is connected to the common mode voltage V CM , the output end is connected to the second end of the first adder; the capacitor current sampler is used to obtain the buck signal and calculate the voltage signal to be judged V according to the buck signal CCS ; Transient detector, used to determine the voltage signal to be determined V CCS Is it greater than the reference voltage V TH1 If yes, output high level judgment signal, if it is less than the reference voltage V TH2 , outputs a low-level state judgment signal; the reverse amplifier is used based on the common-mode voltage V CM , the voltage signal to be judged V CCS Perform reverse amplification processing to obtain a reverse amplified signal.

[0036] The capacitor current sampler includes: capacitor C1, resistor R1, resistor R SEN and transimpedance amplifier EA1; wherein one end of capacitor C1 is connected to the first output end of N phase current channels, and the other end is connected to one end of resistor R1; the other end of resistor R1 is respectively connected to the negative electrode of transimpedance amplifier EA1 and resistor R SEN The positive terminal of the transimpedance amplifier EA1 is connected to the common mode voltage V CM ; The output of the transimpedance amplifier EA1 and the resistor R SEN The other end serves as the output end of the capacitor current sampler.

[0037] Among them, the reverse amplifier includes: resistor R A , resistor R B and operational amplifier EA2; resistor R A One end is connected to the output end of the capacitor current sampler, and the other end is connected to the negative electrode of the operational amplifier EA2 and the resistor R B Connect one end of the resistor R B The other end is connected to the output of the operational amplifier EA2, and the positive terminal of the operational amplifier EA2 is connected to the common mode voltage VCM , the output end of the operational amplifier EA2 is connected to the first input end of the first adder.

[0038] The transient detector includes: comparator CMP1, comparator CMP2 and RS trigger; the negative electrode of comparator CMP1 is connected to the reference voltage V TH1 , the positive electrode is connected to the output of the capacitor current sampler, and the output is connected to the reset terminal of the RS trigger; the positive electrode of the comparator CMP2 is connected to the reference voltage V TH2 , the negative electrode is connected to the output end of the capacitor current sampler, and the output end is connected to the set end of the RS trigger; the output end of the RS trigger is connected to the second input end of the phase control module.

[0039] In a possible implementation, the voltage signal to be determined V CCS The calculation expression satisfies:

[0040] V CCS =V CM -i SEN R SEN ;

[0041] Among them, V CM is the common-mode voltage, R SEN is the resistor connected across the transimpedance amplifier EA1, i SEN is the current flowing through the resistor R SEN of current.

[0042] It should be noted that the adaptive on-time generation module, the multi-phase current conversion module, the current comparison module and the phase control module are all existing circuit modules. For the sake of brevity, the connection relationship between the modules will not be described in detail here.

[0043] It should be noted that when the load changes from light to heavy, the capacitor current I c It is directly related to the load current. Taking a single-phase Buck converter as an example, the relationship between the two is: I c =I L -I load ; Among them, I L Refers to the inductor current, I load Refers to the load current. Figure 5 Is the capacitor current I output by the current conversion module in the single-phase Buck converter c , inductor current I L and load current I load Schematic diagram of the relationship waveform change. Figure 5 As shown, when the load current I load When the capacitor current I output by the single-phase Buck converter changes cReacts immediately. Thanks to this behavior, fast load transients can be anticipated in the control.

[0044] The voltage signal V to be judged has been given in the previous CCS The calculation expression of, when the light load changes to heavy load, i SEN Changes will cause the voltage signal to be judged V CCS The amplitude is greater than the reference voltage V TH1 ,, by turning on the transient enhancement process until the voltage signal to be judged V CCS The amplitude is less than the reference voltage V TH2 After stopping transient enhancement. Taking the single-phase Buck converter as an example, Figure 6 : This is an example diagram of the changes in the inductor current and output voltage after the single-phase Buck converter provided by the embodiment of the present invention performs transient enhancement. Figure 6 As shown in (1) in the figure, when the load changes, the inductor current of the single-phase Buck converter quickly follows the load current change, as shown in Figure 6 As shown in (2) in Figure 2, the recovery time required by the single-phase Buck converter is shorter.

[0045] Corresponding to the above-mentioned transient enhanced multi-phase Buck converter, the present invention further provides a control method for the transient enhanced multi-phase Buck converter, which is used to control the transient enhanced multi-phase Buck converter. The control method includes: real-time acquisition of the current temporally interleaved and superimposed step-down signals output by the multi-phase current conversion module, calculating a voltage signal to be determined using the step-down signals, and generating a corresponding judgment signal based on a judgment result of whether the voltage signal to be determined is greater than a first threshold voltage, wherein the judgment signal is at a high level when the voltage signal to be determined is greater than the first threshold voltage; obtaining N current values ​​corresponding to N output terminals of the multi-phase current conversion module, comparing the N current values ​​to obtain a comparison result, and sending the comparison result to the phase control module, wherein the comparison result is used to reflect the minimum current value among the current N current values ​​and the channel position of the minimum current value; generating corresponding multiple logic control signals based on the judgment signal, the comparison result, and the voltage signal sent by the main circuit; wherein when the judgment signal is at a high level, the corresponding logic control signals are all high level signals; and controlling the multi-phase current conversion module to generate a new step-down signal in response to the multiple logic control signals, wherein when the logic control signals are all high level signals, turning on all single-phase Buck converter circuits in the multi-phase current conversion module until the voltage signal to be determined corresponding to the new step-down signal is less than a second threshold voltage.

[0046] For example, the capacitor current sampling module collects the step-down signal output by the multi-phase current conversion module in real time. Based on the collected step-down signal, the capacitor current sampling module performs calculations to obtain a voltage signal to be judged. The capacitor current sampling module determines whether the calculated voltage signal to be judged is greater than the reference voltage V TH1 If the voltage signal to be judged is less than the reference voltage V TH1 , indicating that the current load state is relatively stable or the fluctuation is within an acceptable range, and no special enhancement measures are required. If the voltage signal to be judged is greater than the reference voltage V TH1 Turning on transient enhancement means that the load has experienced a significant and rapid transient change (only for cases where the load increases dramatically), and the output voltage is at risk of rapid drop. TH1 It will output a high-level judgment signal to the phase control module. The adaptive conduction time generation module responds to these all-high-level logic control signals, and at the same time triggers all single-phase Buck conversion circuits in the multi-phase current conversion module to conduct. In this state, all power phases of the converter are synchronously activated, and the output current capacity is maximized instantly. In this state, the multi-phase current conversion module generates a new buck signal output. The capacitor current sampling module continuously collects this new buck signal, calculates the corresponding new voltage signal to be judged, and repeats the judgment. Once the calculated new voltage signal to be judged is less than V TH2 , indicating that the transient impact has been effectively suppressed and the output voltage has stabilized. At this point, the judgment signal output by the capacitor current sampling module changes from a high level to a low level. In response to the low-level judgment signal, the phase control module resumes its normal control logic (i.e., generating its own logic control signals based on the minimum current phase information output by the current comparison module and the main circuit voltage signal). The adaptive on-time generation module also correspondingly resumes its normal independent interleaved control of each phase, completing the transient enhancement process.

[0047] Based on the control method of the transient-enhanced multi-phase Buck converter provided by the present invention, an autonomous current-sharing strategy based on parallel comparison is designed in the current balancing mechanism. Each phase branch is equipped with a current detection and logic decision-making unit, and autonomous balancing of the phase current is achieved through the current minimum value election mechanism. This distributed architecture without a central controller ensures the equal operating status of each phase branch, effectively eliminates the risk of single-point failure, and greatly improves system reliability. The entire loop adopts an adaptive on-time control mode, which effectively improves the transient response performance and light-load power conversion efficiency of the multi-phase power supply.

[0048] In order to verify the performance of the transient enhanced multi-phase Buck converter provided by the present invention, it is now verified based on simulation software. Figure 7-8 : is a simulation diagram of a transient enhanced multi-phase Buck converter provided by an embodiment of the present invention. Figure 8 A schematic diagram showing the switching of a transient enhanced multi-phase Buck converter from light load to heavy load and then to light load. It should be understood that for ease of observation, the multi-phase current conversion module here only includes two single-phase Buck conversion circuits. Figure 7 As can be seen, the output voltage is red, the two-phase currents are brown and green, respectively, the load current is pink, and the transient enhancement signal is blue. It can be seen that during a load jump, the transient enhancement signal goes high. During this period, the two-phase current is fully open, minimizing the dive and enabling adaptive, rapid tracking and smoothing of load transients. Table 1 shows the various technical parameters.

[0049] Table 1

[0050]

[0051] In view of the inherent response bottleneck problem of traditional multi-phase Buck converters when facing sudden, high-slope load transient changes, the present invention provides a transient-enhanced multi-phase Buck converter and its control method. The transient-enhanced multi-phase Buck converter monitors the dynamic changes of the output capacitor in real time through a capacitor current sampling module, and accurately determines whether the voltage signal represented by the capacitor current sampling module exceeds the threshold voltage V TH1 , in order to sensitively capture high-slope load transient events; once a severe transient is detected, the transient enhancement mechanism is forced to trigger the synchronous conduction of all power phases, instantly releasing the system's maximum current capacity to quickly smooth out output voltage fluctuations; after the system stabilizes, it automatically resumes conventional high-efficiency interleaved control based on minimum current phase selection. While maintaining the inherent high efficiency and low ripple steady-state advantages of the multi-phase Buck converter, this application effectively breaks through the limitations of response lag, poor accuracy, and efficiency loss caused by insufficient bandwidth of the traditional voltage feedback loop, significantly improving the dynamic response speed and output voltage stability under extreme load mutations, and realizing intelligent perception and adaptive suppression of sudden and extremely fast load jumps.

[0052] The above is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A transient enhanced multiphase Buck converter, characterized in that: include: Adaptive on-time generation module, multi-phase current conversion module, current comparison module, phase control module, capacitor current sampling module and main circuit; wherein: The capacitor current sampling module is configured to collect in real time the stepped-down signals output by the multi-phase current conversion module that are currently interleaved and superimposed in time, calculate a voltage signal to be determined using the stepped-down signals, and generate a corresponding determination signal based on a determination result of whether the voltage signal to be determined is greater than a first threshold voltage, wherein the determination signal is at a high level when the voltage signal to be determined is greater than the first threshold voltage; The current comparison module is used to obtain N current values ​​corresponding to the N output terminals of the multi-phase current conversion module, compare the N current values, obtain a comparison result, and send the comparison result to the phase control module, where the comparison result is used to reflect the minimum current value among the current N current values ​​and the channel position where the minimum current value is located; The phase control module is configured to generate a plurality of corresponding logic control signals based on the judgment signal, the comparison result, and the voltage signal sent by the main circuit; wherein, when the judgment signal is at a high level, all the corresponding logic control signals are high level signals; The adaptive on-time generation module is used to respond to the multiple logic control signals and control the multi-phase current conversion module to generate a new step-down signal. When all the logic control signals are high-level signals, all single-phase Buck conversion circuits in the multi-phase current conversion module are turned on until the voltage signal to be determined corresponding to the new step-down signal is less than the second threshold voltage.

2. The transient enhanced multi-phase Buck converter according to claim 1, characterized in that: The multi-phase current conversion module includes N single-phase Buck conversion circuits connected in parallel; the input end of each single-phase Buck conversion circuit is connected to the input end of the multi-phase current conversion module, the input end of the multi-phase current conversion module is connected to the external power supply VIN, the first output end of each single-phase Buck conversion circuit is connected to the output end of the multi-phase current conversion module, the second output end of each single-phase Buck conversion circuit is connected to the first input end of the current comparison module, and the output end of the multi-phase current conversion module outputs the step-down signal; The input end of the capacitor current sampling module is connected to the output end of the multi-phase current conversion module, the first output end is connected to the first input end of the phase control module, and the second output end is connected to the first input end of the main circuit; the second input end of the main circuit is connected to the voltage division signal V FB ; The second to N+1th input terminals of the current comparison module are respectively connected to the second to N+1th output terminals of the multi-phase current conversion module; the output terminal of the main circuit is connected to the N+2th input terminal of the phase control module; The first to Nth output ends of the phase control module are respectively connected to the first to Nth input ends of the adaptive conduction time generation module; the first to Nth output ends of the adaptive conduction time generation module are respectively connected to the control end of a single-phase Buck conversion circuit in the multi-phase current conversion module.

3. The transient enhanced multi-phase Buck converter according to claim 2, wherein: The first threshold voltage is the reference voltage V TH1 , the second threshold voltage is the reference voltage V TH2 , the reference voltage V TH1 is greater than the reference voltage V TH2 ; The capacitor current sampling module includes: a capacitor current sampler, a transient detector and an inverting amplifier; The first input terminal of the capacitor current sampler is connected to the output terminal of the multi-phase current conversion module, and the second input terminal is connected to the common mode voltage V CM , the output end is connected to the first input end of the transient detector and the first input end of the inverting amplifier respectively; The second input terminal of the transient detector is connected to the reference voltage V TH1 , the third input terminal is connected to the reference voltage V TH2 , an output end is connected to the first input end of the phase control module; The second input terminal of the reverse amplifier is connected to the common mode voltage V CM , an output end is connected to the second end of the first adder; The capacitor current sampler is used to obtain the voltage drop signal and calculate the voltage signal to be determined V according to the voltage drop signal. CCS ; The transient detector is used to determine the voltage signal V CCS Is it greater than the reference voltage V TH1 If so, output a high level state judgment signal, if it is less than the reference voltage V TH2 , output the judgment signal of low level state; The inverting amplifier is used to CM , the voltage signal to be judged V CCS Perform reverse amplification processing to obtain a reverse amplified signal.

4. The transient enhanced multi-phase Buck converter according to claim 3, characterized in that: The capacitor current sampler includes: capacitor C1, resistor R1, resistor R SEN and transimpedance amplifier EA1; One end of the capacitor C1 is connected to the first output end of the N phase current channels, and the other end is connected to one end of the resistor R1; the other end of the resistor R1 is connected to the negative electrode of the transimpedance amplifier EA1 and the resistor R SEN The positive electrode of the transimpedance amplifier EA1 is connected to the common mode voltage V CM The output end of the transimpedance amplifier EA1 and the resistor R SEN The other end serves as the output end of the capacitor current sampler.

5. The transient enhanced multi-phase Buck converter according to claim 4, characterized in that: The reverse amplifier includes a resistor R A , resistor R B and operational amplifier EA2; The resistor R A One end is connected to the output end of the capacitor current sampler, and the other end is connected to the negative electrode of the operational amplifier EA2 and the resistor R B One end of the resistor R B The other end is connected to the output end of the operational amplifier EA2, and the positive electrode of the operational amplifier EA2 is connected to the common mode voltage V CM , the output end of the operational amplifier EA2 is connected to the first input end of the first adder.

6. The transient enhanced multi-phase Buck converter according to claim 5, characterized in that: The transient detector includes: a comparator CMP1, a comparator CMP2 and an RS trigger; The negative electrode of the comparator CMP1 is connected to the reference voltage V TH1 , the positive electrode is connected to the output end of the capacitor current sampler, and the output end is connected to the reset end of the RS trigger; The positive electrode of the comparator CMP2 is connected to the reference voltage V TH2 , the negative electrode is connected to the output end of the capacitor current sampler, and the output end is connected to the set end of the RS trigger; The output end of the RS trigger is connected to the second input end of the phase control module.

7. The transient enhanced multi-phase Buck converter according to claim 2, wherein: The main circuit includes: an error amplifier, a comparator, a first adder, a second adder and a sawtooth wave generator; wherein: The input terminal of the error amplifier and the first terminal of the first adder are both connected to the voltage-divided signal V FB , the output end of the error amplifier is connected to the first end of the second adder, and the output end of the sawtooth wave generator is connected to the second end of the second adder; The second end of the first adder is connected to the second output end of the capacitor current sampling module; The output end of the first adder is connected to the positive electrode of the comparator, the output end of the second adder is connected to the negative electrode of the comparator, and the output end of the comparator is respectively connected to the input end of the sawtooth wave generator and the N+2th input end of the phase control module.

8. The transient enhanced multi-phase Buck converter according to claim 2, wherein: The external load includes: feedback resistor R FB1 , feedback resistor R FB2 , load capacitance CL and load resistance RL; Among them, the feedback resistor R FB1 One end of the load capacitor CL and one end of the load resistor RL are all connected to the output end of the multi-phase current conversion module; The feedback resistor R FB1 The other end of the feedback resistor R FB2 one end of the first adder, the second input end of the first adder and the input end of the error amplifier; The feedback resistor R FB2 The other end of the load capacitor CL and the other end of the load resistor RL are grounded.

9. The transient enhanced multi-phase Buck converter according to claim 3, wherein: The voltage signal to be determined V CCS The calculation expression satisfies: V CCS =V CM -i SEN R SEN ; Among them, V CM is the common-mode voltage, R SEN is the resistor connected across the transimpedance amplifier EA1, i SEN is the current flowing through the resistor R SEN of current.

10. A control method for a transient enhanced multi-phase Buck converter, characterized in that: The control method is used to control the transient enhanced multi-phase Buck converter according to any one of claims 1 to 9; the control method comprises: collecting the time-staggered stepped-down signals output by the multi-phase current conversion module in real time, calculating a voltage signal to be determined using the stepped-down signals, and generating a corresponding determination signal based on a determination result of whether the voltage signal to be determined is greater than a first threshold voltage, wherein the determination signal is at a high level when the voltage signal to be determined is greater than the first threshold voltage; Obtaining N current values ​​corresponding to the N output terminals of the multiphase current conversion module, comparing the N current values ​​to obtain a comparison result, and sending the comparison result to the phase control module, wherein the comparison result is used to reflect the minimum current value among the current N current values ​​and the channel position where the minimum current value is located; generating a plurality of corresponding logic control signals based on the judgment signal, the comparison result, and the voltage signal sent by the main circuit; wherein, when the judgment signal is at a high level, all the corresponding logic control signals are high level signals; In response to the multiple logic control signals, the multi-phase current conversion module is controlled to generate a new step-down signal, wherein, when all the logic control signals are high-level signals, all single-phase Buck conversion circuits in the multi-phase current conversion module are turned on until the voltage signal to be judged corresponding to the new step-down signal is less than the second threshold voltage.

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