Multi-phase power converter and method of controlling the same

Abstract

A multiphase power converter and its control method are disclosed. The multiphase power converter includes: multiple power stage circuits for converting an input voltage into an output voltage, wherein each power stage circuit is coupled to the input voltage and controls a corresponding inductor via at least one switch, the inductor transferring energy to the output voltage; a current sensing circuit coupled to the multiple power stage circuits for sensing the inductor current flowing through each inductor in each power stage circuit; and a control circuit including a transient current response module for triggering a transient current response when the current of at least one inductor exceeds a transient current threshold, thereby increasing or decreasing the number of operating phases of the multiple power stage circuits to suppress overshoot or undershoot of the output voltage.

Description

Technical Field

[0001] This invention relates to a multiphase power converter, and more particularly to a multiphase power converter that can determine in real time whether to increase or decrease the number of operating phases based on inductor current. The invention also relates to a control method for this multiphase power converter. Background Technology

[0002] As electronic products become increasingly diverse in function and their processing power continues to improve, the demand for stable and efficient power supplies is also gradually increasing. Multiphase power converters are widely used in high-efficiency and high-current applications to improve power supply efficiency and reduce output voltage ripple. Figure 1A This diagram illustrates a typical prior art multiphase power converter, which is a parallel architecture of four-phase buck power stage circuits. The multiphase power converter comprises four power stage circuits (PowerStage, PS1 to PS4). The first phase power stage circuit PS1 includes an upper bridge switch Q1H, a lower bridge switch Q1L, and an inductor L1; the second phase power stage circuit PS2 includes an upper bridge switch Q2H, a lower bridge switch Q2L, and an inductor L2; the third phase power stage circuit PS3 includes an upper bridge switch Q3H, a lower bridge switch Q3L, and an inductor L3; and the fourth phase power stage circuit PS4 includes an upper bridge switch Q4H, a lower bridge switch Q4L, and an inductor L4. The input terminals of these four power stage circuits are coupled to the input voltage VIN, and each outputs energy to the output voltage VO through inductors, forming a multiphase buck architecture to collectively output a stable output voltage VO, thereby achieving load current shunting and improving overall efficiency.

[0003] Figure 1B This diagram illustrates the relationship between the load current ILOAD and the power conversion efficiency EFF of a conventional multiphase power converter. Figure 1B As shown, existing technologies, in order to improve power conversion efficiency, automatically perform phase adding and phase shedding based on the magnitude of the load current ILOAD. Figure 1BThe curves in the diagram, from left to right, represent: a single operating phase operating in Discontinuous Conduction Mode (DCM), a single operating phase operating in Continuous Conduction Mode (CCM), two operating phases, and three operating phases, respectively. The operating phase is gradually decreased as the load current ILOAD decreases, and gradually increased as the load current ILOAD increases. Traditional methods often determine phase additions and subtractions based on the average inductor current of the operating phase. While this average current monitoring mechanism can filter out inductor current ripple and avoid frequent switching (such as oscillations at critical points), the average method suffers from hysteresis: when the load suddenly increases or decreases, the phase does not switch in real time. This often results in output voltage overshoot / undershoot and subsequent oscillations. Especially under rapid load transients, compensation in the current and voltage loops may cause output voltage ringing, further affecting system stability.

[0004] Figure 1C This displays a schematic diagram of the relevant signal waveforms of a prior art multiphase power converter. For example... Figure 1C As shown, three signal waveforms are plotted sequentially from top to bottom: load current ILOAD, instantaneous inductor current IL (including the first-phase inductor current IL1 and the second-phase inductor current IL2), and output voltage VO. At time t1, the load current ILOAD suddenly increases, and the first-phase inductor current IL1 increases accordingly due to the control of the feedback loop. When time t2 is reached, the average inductor current of all phases (which is also the average inductor current of the first phase) exceeds the preset average current threshold (not shown in the figure), enabling the second phase to start operating, and the second-phase inductor current IL2 rises accordingly. Between time t1 and t2, the output voltage VO experiences significant undershoot (US) and subsequent oscillation. Then at time t3, the load current ILOAD suddenly decreases, and the feedback loop causes the inductor currents IL1 and IL2 of the first and second phases to begin to decrease. However, the second-phase power stage is not turned off until time t4. During this period, the output voltage VO experiences overshoot (OS) and subsequent output voltage ringing, affecting output stability.

[0005] Please refer to again Figure 1D This shows another related signal waveform diagram of the aforementioned prior art multiphase power converter. Figure 1D Similar situation Figure 1C However, this is a simplified version, intended to further illustrate another drawback of existing multiphase power converters. For example... Figure 1DAs shown, the upper signal waveform represents the output voltage VO, while the two lower signal waveforms represent the inductor currents IL1 and IL2 of the first and second phases, respectively. Under certain instantaneous load current conditions, at time point t5, the load current increases, and the inductor current IL1 of the first phase power stage rises. When the average inductor current of the first phase exceeds the preset average current threshold (not shown in the figure), the instantaneous inductor current IL1 of the first phase simultaneously triggers the overcurrent protection mechanism, causing the instantaneous inductor current IL1 of the first phase to be limited by the current limiting level CL. Due to the hysteresis response in the existing technology, the second phase power stage circuit does not start operating until time point t6, further increasing the undershoot (US') amplitude of the output voltage VO, making the stability of the output voltage VO more severely affected.

[0006] Compared to the prior art, the present invention provides a control circuit for controlling a stackable multiphase power converter, which can continue to achieve current sharing even when the number of startup phases of the stackable multiphase power converter changes, without being affected by the change in the number of startup phases, thereby achieving advantages such as more energy saving, higher efficiency and stable output current and voltage. Summary of the Invention

[0007] In one viewpoint, the present invention provides a multiphase power converter, comprising: a plurality of power stage circuits for converting an input voltage into an output voltage, wherein the plurality of power stage circuits are respectively coupled to the input voltage and each controls a corresponding inductor through at least one switch, the inductor transferring energy to the output voltage; a current sensing circuit coupled to the plurality of power stage circuits for sensing an inductor current flowing through the inductor in each power stage circuit; and a control circuit including an instantaneous current response module for triggering an instantaneous current response when at least one of the inductor currents exceeds an instantaneous current threshold, thereby increasing or decreasing the number of operating phases of the plurality of power stage circuits, thereby suppressing overshoot or undershoot of the output voltage.

[0008] In one embodiment, the multiphase power converter further includes: an average current circuit coupled to the plurality of power stage circuits for averaging the multiple inductor currents of the plurality of power stage circuits to generate an average current; wherein the control circuit further includes an average current response module for determining the number of operating phases based on the average current and at least an average current threshold, thereby improving a conversion efficiency.

[0009] In one embodiment, the multiphase power converter further includes: an output voltage sensing circuit coupled to the plurality of power stage circuits for sensing the output voltage; wherein the control circuit further includes an instantaneous voltage response module for triggering an instantaneous voltage response when the change in the output voltage exceeds an instantaneous voltage difference threshold, so as to increase or decrease the number of operating phases, thereby suppressing overshoot or undershoot of the output voltage.

[0010] In one embodiment, during the instantaneous voltage response, the instantaneous voltage response module drives all of the plurality of power stage circuits to operate or deactivate all of the plurality of power stage circuits for a preset period.

[0011] In one embodiment, the average current circuit includes multiple low-pass filters corresponding to the multiple power stage circuits to low-pass filter the multiple inductor currents to obtain the average current.

[0012] In one embodiment, the current sensing circuit includes: a positive inductor current sensing circuit for sensing a positive inductor current in the inductor current of each power stage circuit; and / or a negative inductor current sensing circuit for sensing a negative inductor current in the inductor current of each power stage circuit; wherein the instantaneous current response module is used to trigger the instantaneous current response when at least one of the positive inductor currents exceeds an instantaneous positive current threshold and / or at least one of the negative inductor currents exceeds an instantaneous negative current threshold, so as to increase or decrease the number of operating phases.

[0013] In one embodiment, during the instantaneous current response, the instantaneous current response module drives all of the plurality of power stage circuits to operate, or disables all power stage circuits except for one phase, retaining only one phase power stage circuit to maintain operation for a preset period of time, so as to suppress overshoot or undershoot of the output voltage.

[0014] In one embodiment, the instantaneous current threshold is higher than the at least one average current threshold.

[0015] In one embodiment, when the control circuit reduces the number of operating phases, one of the upper or lower bridge switches of the at least one switch of the power stage circuit in the off operation is held for a momentary period, so that the corresponding inductor current flows through the integrated diode of the upper or lower bridge switch, thereby increasing the absolute value of the inductor's voltage across the diode and thus shortening the momentary period.

[0016] In another viewpoint, the present invention also provides a control method for controlling a multiphase power converter, wherein the multiphase power converter includes a plurality of power stage circuits for converting an input voltage into an output voltage, wherein the plurality of power stage circuits are respectively coupled to the input voltage and each controls a corresponding inductor through at least one switch, the inductor transferring energy to the output voltage, the control method comprising: sensing an inductor current flowing through the inductor in each power stage circuit; and triggering an instantaneous current response when at least one of the inductor currents exceeds an instantaneous current threshold, thereby increasing or decreasing the number of operating phases of the plurality of power stage circuits, thereby suppressing overshoot or undershoot of the output voltage.

[0017] In another viewpoint, the present invention also provides a control method for controlling a multiphase power converter, wherein the multiphase power converter includes multiple power stage circuits for converting an input voltage into an output voltage, wherein the multiple power stage circuits are respectively coupled to the input voltage and each controls a corresponding inductor through at least one switch, the inductor transferring energy to the output voltage, the control method comprising: sensing an inductor current flowing through the inductor in each power stage circuit; averaging the multiple inductor currents of the multiple power stage circuits to generate an average current; sensing the output voltage; and when the change in the output voltage exceeds a momentary... When the voltage difference threshold is reached, an instantaneous voltage response is triggered to increase or decrease the number of operating phases of the plurality of power stage circuits, thereby suppressing overshoot or undershoot of the output voltage; when the change in the output voltage does not exceed the instantaneous voltage difference threshold, when at least one of the inductor currents exceeds an instantaneous current threshold, an instantaneous current response is triggered to increase or decrease the number of operating phases, thereby suppressing overshoot or undershoot of the output voltage; and in each power stage circuit, when the inductor current does not exceed the instantaneous current threshold, the number of operating phases is determined based on the average current and at least one average current threshold, thereby improving a conversion efficiency.

[0018] In one embodiment, the control method further includes: during the instantaneous voltage response, driving all of the plurality of power stage circuits to operate or deactivating all of the plurality of power stage circuits for a preset period.

[0019] In one embodiment, the control method further includes: in the instantaneous current response, driving all of the plurality of power stage circuits to operate, or disabling the other power stage circuits except for one of the phases, and retaining only one phase power stage circuit to maintain operation for a preset period of time, so as to suppress overshoot or undershoot of the output voltage.

[0020] In one embodiment, when a first number of operating phases determined based on at least one inductor current exceeding the instantaneous current threshold is inconsistent with a second number of operating phases determined based on the average current and the average current threshold, the first number of operating phases is used as the number of operating phases to be executed first.

[0021] In the above embodiments, when the number of the second operating phases is less than a first preset number and the inductor current is a positive inductor current, the number of the first operating phases is greater than a second preset number; wherein when the number of the second operating phases is greater than a third preset number and the inductor current is a negative inductor current, the number of the first operating phases is less than a fourth preset number.

[0022] The following detailed description through specific embodiments will make it easier to understand the purpose, technical content, features and effects achieved by the present invention. Attached Figure Description

[0023] Figure 1A This illustrates a typical existing multiphase power converter.

[0024] Figure 1B This diagram illustrates the relationship between the load current ILOAD and the power conversion efficiency EFF of a conventional multiphase power converter.

[0025] Figure 1C This diagram shows the relevant signal waveforms of existing multiphase power converters.

[0026] Figure 1D This diagram shows another relevant signal waveform of a prior art multiphase power converter.

[0027] Figure 2 A schematic diagram showing an embodiment of the circuit of the multiphase power converter of the present invention is shown.

[0028] Figure 3 A schematic diagram showing another embodiment of the circuit of the multiphase power converter of the present invention is shown.

[0029] Figure 4 A schematic diagram showing a specific embodiment of the circuit of the multiphase power converter of the present invention is provided.

[0030] Figure 5 A schematic diagram showing an embodiment of the average current circuit in the circuit of the multiphase power converter of the present invention is shown.

[0031] Figure 6 This diagram shows an embodiment of one of the hysteresis comparators in the average current response module of the multiphase power converter of the present invention.

[0032] Figure 7A schematic diagram illustrating an embodiment of the power stage circuit of the present invention shows how the lower bridge switch is held in a turn-off operation during a transient period, so that the corresponding inductor current flows through the body diode of the lower bridge switch.

[0033] Figure 8 This diagram shows relevant signal waveforms of an embodiment of the multiphase power converter of the present invention.

[0034] Figure 9A and 9B The diagrams show relevant signal waveforms of an embodiment of a multiphase power converter of the prior art and the present invention.

[0035] Figure 10 This diagram shows an operation flowchart of an embodiment of the control method of the present invention.

[0036] Figure 11 A flowchart illustrating an embodiment of the instantaneous voltage response of the control method of the present invention is shown.

[0037] Figure 12 A flowchart illustrating an embodiment of the instantaneous current response of the control method of the present invention is shown.

[0038] Figure 13 A flowchart illustrating an embodiment of the control method of the present invention for triggering instantaneous current response is shown.

[0039] Figure 14 A flowchart illustrating an embodiment of the control method of the present invention for triggering instantaneous current response is shown.

[0040] Explanation of symbols in the diagram

[0041] 10, 20, 30: Multiphase power converters

[0042] 11: Load circuit

[0043] 101, 201, 301, PS1: Power stage circuits

[0044] 102, 202, 302, PS2: Power stage circuit

[0045] 103, 203, 303, PS3: Power stage circuits

[0046] 104, 204, 304, PS4: Power stage circuits

[0047] 111, 211, 311: Current sensing circuits

[0048] 120, 220, 320: Control circuit

[0049] 121, 221, 321: Instantaneous Current Response Module

[0050] 212, 312: Average current circuit

[0051] 213, 313: Output voltage sensing circuit

[0052] 324: Feedback and Pulse Width Modulation Circuit

[0053] 325: Phase Quantity Control Circuit

[0054] 2121: Average Circuit

[0055] 3011, 3021, 3031, 3041: Drive circuits

[0056] 3111: Forward Inductor Current Sensing Circuit

[0057] 3112: Negative Inductor Current Sensing Circuit

[0058] 3221: Hysteresis Comparator

[0059] CL: Current Limit Level

[0060] CS1, CS2, CS3, CS4: Inductor current signals

[0061] IL1, IL2, IL3, IL4: Inductor current

[0062] ILOAD: Load current

[0063] Ilth, ILth': Instantaneous current threshold

[0064] ISEN: Average Current

[0065] ITL: Instantaneous Current Signal

[0066] L1, L2, L3, L4: Inductors

[0067] LPF: Low-pass filter

[0068] LX1, LX2, LX3, LX4: Phase node voltages

[0069] NOC1-NOC4: Negative sensing signals

[0070] OS: Overshoot

[0071] POC1-POC4: Forward sensing signals

[0072] PWM0: Reference PWM signal

[0073] SPW1, SPW2, SPW3, SPW4: PWM signals

[0074] Q1H, Q2H, Q3H, Q4H: Bridge switch

[0075] Q1L, Q2L, Q3L, Q4L: Lower bridge switch

[0076] RAMP: Ramp signal

[0077] S10, S20, S30, S40, S50, S51, S60, S60', S60", S61, S61', S61", S511, S512, S611, S612: Steps

[0078] SW1, SW2, SW3, SW4: Switches

[0079] t1, t2, t3, t4, t5, t6: Time points

[0080] US, US': under-excited

[0081] VIN: Input voltage

[0082] VO: Output voltage

[0083] Vth1: First average current threshold

[0084] Vth2: Second average current threshold

[0085] Vth3: Third average current threshold

[0086] Vthqr: Instantaneous voltage difference threshold Detailed Implementation

[0087] The accompanying drawings in this invention are schematic and are primarily intended to illustrate the coupling relationships between circuits and the relationships between signal waveforms. The circuits, signal waveforms, and frequencies are not drawn to scale. For clarity, many practical details will be described in the following description, but this is not intended to limit the scope of the patent application.

[0088] Figure 2 A schematic diagram showing an embodiment of the circuit of the multiphase power converter of the present invention is shown. For example... Figure 2As shown, the multiphase power converter 10 includes: multiple power stage circuits 101, 102, 103, and 104 for converting the input voltage VIN into an output voltage VO. The multiple power stage circuits 101, 102, 103, and 104 are respectively coupled to the input voltage VIN, and each controls a corresponding inductor L1, L2, L3, and L4 through at least one switch SW1, SW2, SW3, and SW4. The inductors L1, L2, L3, and L4 transfer energy to the output voltage VO. A current sensing circuit 111 is coupled to the multiple power stage circuits 101, 102, 103, and 104. 2, 103, and 104 are used to sense the inductor currents IL1, IL2, IL3, and IL4 flowing through the corresponding inductors L1, L2, L3, and L4 in each power stage circuit 101, 102, 103, and 104; and the control circuit 120 includes an instantaneous current response module 121, which triggers an instantaneous current response when at least one inductor current IL1, IL2, IL3, or IL4 exceeds an instantaneous current threshold, thereby increasing or decreasing the number of operating phases of the multiple power stage circuits 101, 102, 103, and 104, and thus suppressing overshoot or undershoot of the output voltage VO. The multiphase power converter 10 described above can quickly adjust the number of operating power stages according to the load current ILOAD change requirements through the instantaneous current response module 121 to ensure the stability of the output voltage VO, and further improve the conversion efficiency and power supply stability.

[0089] Figure 3 A schematic diagram showing another embodiment of the circuit of the multiphase power converter of the present invention is shown. (See diagram below.) Figure 3 As shown, the multiphase power converter 20 includes multiple power stage circuits 201, 202, 203, and 204 for converting the input voltage VIN into an output voltage VO. Each power stage circuit 201, 202, 203, and 204 is coupled to the input voltage VIN and controls corresponding inductors L1, L2, L3, and L4 via at least one corresponding switch SW1, SW2, SW3, and SW4. The inductors L1, L2, L3, and L4 transfer energy to the output voltage VO. The multiphase power converter 20 further includes a current sensing circuit 211, an average current circuit 212, and an output voltage sensing circuit 213. The current sensing circuit 211 is coupled to the multiple power stage circuits 201, 202, 203, and 204 to sense the inductor currents IL1, IL2, IL3, and IL4 flowing through the corresponding inductors in each power stage circuit. The average current circuit 212 is also coupled to the power stage circuits 201, 202, 203, and 204 to average the current of these multiple inductors, thereby generating an average current ISEN. In addition, the output voltage sensing circuit 213 is coupled to the output voltage VO to sense changes in the output voltage VO.

[0090] The control circuit 220 of this embodiment includes a transient current response module 221, an average current response module 222, and a transient voltage response module 223. When the transient current response module 221 detects that at least one inductor current IL1, IL2, IL3, or IL4 exceeds a transient current threshold, it triggers a transient current response to increase or decrease the number of power stage circuits in operation, thereby suppressing overshoot or undershoot of the output voltage VO. The average current response module 222 is used to determine the number of operating phases based on the average current ISEN and at least one average current threshold to improve conversion efficiency. Furthermore, the transient voltage response module 223 is used to, from one perspective, indicate that the load has a high slope (absolute value) when the change in output voltage VO exceeds a transient voltage difference threshold, trigger a transient voltage response to increase or decrease the number of power stage circuits in operation, thereby suppressing overshoot or undershoot of the output voltage VO.

[0091] In one embodiment, the instantaneous voltage response module 223 is used to trigger an instantaneous voltage response when the change in output voltage VO exceeds an instantaneous voltage difference threshold, and to immediately drive all power stage circuits to operate simultaneously to rapidly increase the total output current when it is necessary to increase the number of operating power stage circuits; or to deactivate all power stage circuits for a preset period to rapidly reduce the total output current when it is necessary to reduce the number of operating power stage circuits. It should be noted that "deactivation" means that both the upper bridge switch and the lower bridge switch are turned off, thereby rapidly suppressing the overshoot or undershoot of the output voltage VO.

[0092] In one embodiment, during the instantaneous current response period, the instantaneous current response module 221 drives all power stage circuits to operate when it is necessary to increase the number of operating power stage circuits; or disables all other power stage circuits except one phase for a preset period when it is necessary to reduce the number of operating power stage circuits, thereby effectively suppressing overshoot or undershoot of the output voltage VO.

[0093] Through this multi-level and differentiated control method, the multiphase power converter 10 can effectively handle load changes of varying degrees, maintaining high stability of the output voltage VO and high system conversion efficiency. For example, in the multiphase power converter of the present invention, three corresponding response mechanisms are set according to the different slopes of the load current ILOAD change: average current response, instantaneous current response, and instantaneous voltage response. The so-called average current response is the aforementioned response mechanism that determines the number of operating phases based on the average current ISEN and at least one average current threshold.

[0094] The average current response mechanism is applicable when the slope of the load current ILOAD changes within a first slope range. When the load current ILOAD changes slowly and steadily, such as when the load of a multiphase power converter changes gradually, the average current response adjusts the number of operating phases by sensing the average value of the inductor current, thereby effectively improving conversion efficiency.

[0095] The instantaneous current response mechanism is applicable when the slope of the load current ILOAD change falls within a second slope range, where the rate of change of the load current ILOAD is higher than that of the first slope range. In this case, since the load current ILOAD changes relatively quickly, the average current response may not be sufficient to handle it in time. Therefore, the instantaneous current response immediately adjusts the number of operating phases by real-time sensing whether the inductor current exceeds a preset instantaneous current threshold, in order to quickly suppress any possible overshoot or undershoot of the output voltage.

[0096] The instantaneous voltage response mechanism is specifically designed for applications where the load current ILOAD change slope falls within the third slope range, representing the scenario where the load current ILOAD changes at its fastest rate. Such load transients are quite drastic; for example, a CPU rapidly transitioning from a low-power state to a high-power state can cause a significant instantaneous shift in the output voltage. In such cases, average current response or instantaneous current response alone may not be sufficient to stabilize the output voltage in time. Therefore, the instantaneous voltage response mechanism directly senses the instantaneous change in output voltage and immediately drives all power stages or briefly halts their operation to extremely quickly suppress drastic fluctuations in output voltage.

[0097] Therefore, this invention sets three different response strategies based on the slope of the load current ILOAD change, and has the following clear slope order relationship: the slope of the load current ILOAD change in the first slope change range is lower than the slope of the load current ILOAD change in the second slope change range, and the slope of the load current ILOAD change in the second slope change range is lower than the slope of the load current ILOAD change in the third slope change range, so as to effectively and accurately handle various load transient situations.

[0098] Figure 4 A schematic diagram showing a specific embodiment of the circuit of the multiphase power converter of the present invention is illustrated. For example... Figure 4 As shown, the multiphase power converter 30 includes multiple power stage circuits 301, 302, 303 and 304 for converting the input voltage VIN into the output voltage VO. Each power stage circuit 301, 302, 303 and 304 includes at least one set of switching elements for controlling the corresponding inductors L1, L2, L3 and L4. Each inductor transfers energy to the output voltage VO.

[0099] The multiphase power converter 30 further includes a current sensing circuit 311, an average current circuit 312, an output voltage sensing circuit 313, and a control circuit 320. The current sensing circuit 311 includes a positive inductor current sensing circuit 3111 and a negative inductor current sensing circuit 3112, used to sense the positive and negative inductor currents of each power stage circuit respectively, and send the positive sensing signals POC1-POC4 and the negative sensing signals NOC1-NOC4 corresponding to the inductor currents IL1, IL2, IL3, and IL4 to the instantaneous current response module 321 of the control circuit 320. In this embodiment, the positive inductor current sensing circuit 3111 and the negative inductor current sensing circuit 3112 obtain, for example, positive sensing signals POC1-POC4 and negative sensing signals NOC1-NOC4 related to the positive inductor current of each phase power stage circuit based on the phase node voltages LX1, LX2, LX3 and LX4 of the power stage circuits 301, 302, 303 and 304.

[0100] It should be noted that "positive inductor current" refers to the inductor current flowing from the phase node through the inductor to the output voltage; "negative inductor current" is the opposite, flowing from the output voltage through the inductor to the phase node. Specifically, when at least one positive inductor current exceeds the instantaneous current threshold (which is a positive value), an instantaneous current response is triggered to increase the number of operating phases of multiple power stage circuits 101, 102, 103, and 104. Conversely, when at least one negative inductor current exceeds the instantaneous current threshold (which is a negative value), an instantaneous current response is triggered to decrease the number of operating phases of multiple power stage circuits 101, 102, 103, and 104.

[0101] The average current circuit 312 averages the inductor currents IL1, IL2, IL3, and IL4 output from each power stage circuit 301 to 304 to generate an average current ISEN. In one embodiment, the average current circuit 312 generates a signal related to the average current ISEN (here still referred to as average current ISEN) based, for example, on the inductor current signals CS1, CS2, CS3, and CS4 corresponding to the drain terminal voltages of the power switches of the power stage circuits 301, 302, 303, and 304.

[0102] The control circuit 320 includes a transient current response module 321, an average current response module 322, a transient voltage response module 323, a feedback and pulse width modulation circuit 324, and a phase quantity control circuit 325. The transient current response module 321 triggers a transient current response when at least one inductor current exceeds a transient current threshold, thereby increasing or decreasing the number of power stage circuits in operation. In one embodiment, the transient current response module 321 drives all power stage circuits to operate during the transient current response period, or disables all other power stage circuits except for one phase for a preset period, thereby effectively suppressing overshoot or undershoot of the output voltage VO.

[0103] The average current response module 322 determines the optimal number of operating phases based on the average current ISEN and one or more average current thresholds to improve conversion efficiency. It can also be paired with a hysteresis comparison function to prevent output voltage oscillations caused by repeated switching of the number of phases near the thresholds. In one embodiment, the number of operating phases is one when the average current ISEN is less than the first average current threshold Vth1; two when the average current ISEN is between the first average current threshold Vth1 and the second average current threshold Vth2; three when the average current ISEN is between the second average current threshold Vth2 and the third average current threshold Vth3; and four when the average current ISEN is greater than the third average current threshold Vth3.

[0104] The instantaneous voltage response module 323 is used to determine whether the instantaneous change in the output voltage VO exceeds an instantaneous voltage difference threshold Vthqr. When this threshold is exceeded, the instantaneous voltage response is triggered. In one embodiment, the phase quantity control circuit 325 drives all power stage circuits to operate simultaneously or completely disable them for a preset period of time to immediately and effectively suppress overshoot or undershoot of the output voltage VO.

[0105] Furthermore, the feedback and pulse width modulation circuit 324 is used to generate a reference PWM signal PWM0 based on the input voltage VIN, the output voltage VO, and the ramp signal RAMP in a feedback and pulse width modulation manner, so as to provide a reference signal for each power stage circuit. The method by which the feedback and pulse width modulation circuit 324 generates the reference PWM signal PWM0 is well known to those skilled in the art and will not be described in detail here.

[0106] The phase quantity control circuit 325 determines the operating power stage circuit based on the reference PWM signal PWM0 and the outputs of the instantaneous current response module 321, the average current response module 322, and the instantaneous voltage response module 323, and generates PWM signals SPW1, SPW2, SPW3, and SPW4 to be input to the power stage circuits 301, 302, 303, and 304 respectively. In addition, the power stage circuits 301, 302, 303, and 304 respectively include drive circuits 3011, 3021, 3031, and 3041 to drive the power switches therein according to the PWM signals SPW1, SPW2, SPW3, and SPW4 respectively, thereby converting the input voltage VIN into the output voltage VO.

[0107] Figure 5 This diagram shows an embodiment of the average current circuit in the multiphase power converter of the present invention. (See attached diagram.) Figure 5 As shown, the averaging current circuit 212 includes multiple low-pass filters (LPFs), corresponding to the inputs of inductor currents IL1, IL2, IL3, and IL4, respectively. Each LPF receives and low-pass filters its corresponding inductor current signal to remove high-frequency noise and obtain a stable average or approximately averaged DC current signal. Then, the output signals of each LPF are input to the input of an averaging circuit 2121. This averaging circuit 2121 can be any circuit suitable for signal averaging, such as, but not limited to, an active averaging circuit composed of a resistor network, operational amplifiers, or other equivalent circuits. Through this averaging circuit 2121, the mathematical average value of the aforementioned multi-phase current signals can be calculated accurately and effectively, forming a stable and accurate average current ISEN, which serves as a reference for subsequent control circuits to control the number of phases, thereby improving power conversion efficiency and ensuring system stability.

[0108] Figure 6 This diagram illustrates an embodiment of one of the hysteresis comparators 3221 of the average current response module 322 of the multiphase power converter of the present invention. Figure 6As shown, the hysteresis comparator 3221 includes two input terminals, which are the aforementioned average current ISEN and the first average current threshold Vth1, respectively. This hysteresis comparator 3221 has a built-in hysteresis characteristic. When the input average current ISEN exceeds the upper threshold (i.e., Vth1 plus the built-in hysteresis range), its output will generate a high-level signal to trigger the phase quantity control circuit 325 to increase the number of operating power stage circuits by one. Conversely, when the average current ISEN drops below the lower threshold (i.e., Vth1 minus the built-in hysteresis range), its output will generate a low-level signal to trigger the control circuit to decrease the number of operating power stage circuits by one. Through this hysteresis characteristic, the average current response module 322 can avoid frequent switching of the average current ISEN when it approaches the first average current threshold Vth1, thus effectively preventing oscillation of the output voltage VO and improving the stability and reliability of the system.

[0109] Figure 7 This diagram illustrates an embodiment of the power stage circuit of the multiphase power converter of the present invention, which shortens the instantaneous response time by keeping the lower bridge switch off during a transient period, allowing inductor current to flow through the body diode of the lower bridge switch, when reducing the number of operating phases. (See attached diagram.) Figure 7 As shown, this power stage circuit 301 includes an upper bridge switch and a lower bridge switch, as well as corresponding inductors. When the output voltage VO experiences a momentary change exceeding a preset momentary voltage difference threshold Vthqr, the momentary voltage response module 323 will trigger a momentary voltage response, thereby driving the power stage circuit 301 to perform a rapid adjustment of the number of operating phases.

[0110] Specifically, when it is decided to reduce the number of operating phases of the power stage circuit 301, the instantaneous voltage response module 323 will control the lower bridge switch to remain in the off state, so that the inductor current that originally flowed through the lower bridge switch flows through the integrated diode of the lower bridge switch instead. In this way, during the instantaneous period, a larger absolute value of the inductor voltage across the diode can be generated by the conduction of the body diode, which can quickly reduce the inductor current and stabilize the output voltage VO, thereby effectively shortening the switching time of the instantaneous response and improving the instantaneous characteristics of the output voltage.

[0111] Furthermore, this control strategy, which shortens the instantaneous response time by conducting the body diode, can be applied not only to the aforementioned instantaneous voltage response mode, but also to the instantaneous current response module and average current response module described in this invention. When the number of operating phases is reduced, the overall dynamic response capability and stability of the system can be further improved.

[0112] Figure 8This diagram illustrates the relevant signal waveforms of an embodiment of the multiphase power converter of the present invention. In this embodiment, the waveform changes of the output voltage VO and the two-phase inductor currents IL1 and IL2 are displayed sequentially from top to bottom, with the horizontal axis representing time t. Figure 8 As shown, at time point t1, the inductor current IL1 of the first phase reaches the set instantaneous current threshold ILth. At this time, the instantaneous current response module immediately triggers an instantaneous current response, instantly increasing the number of operating phases of the power stage circuit, causing the inductor current IL2 of the second phase to rise rapidly from time point t1. Because this embodiment increases the operation of another phase before the first phase inductor current IL1 reaches the current limit, it effectively improves the current supply capability and quickly suppresses undershoot or overshoot of the output voltage VO. In contrast, when the instantaneous current response is triggered according to the embodiment of this invention, the existing average current monitoring mechanism has not yet triggered the phase addition / subtraction response. In other words, compared to the prior art, this invention can suppress undershoot or overshoot of the output voltage VO more quickly.

[0113] Therefore, the undershoot amplitude of the output voltage VO is significantly reduced. The output voltage undershoot amplitude shown in this embodiment can be reduced to only about 1% compared to the prior art, fully demonstrating that the present invention can effectively improve the instantaneous stability of the output voltage through the instantaneous current response mechanism, and significantly improve the system performance and reliability of the multiphase power converter.

[0114] Figure 9A and Figure 9B The diagrams show a comparison of relevant signal waveforms between the prior art and a multiphase power converter according to an embodiment of the present invention. Figure 9A The output voltage VO and the current of each phase inductor (such as the first phase inductor current IL1, the second phase inductor current IL2, the third phase inductor current IL3 and the fourth phase inductor current IL4) are displayed sequentially from top to bottom, and the horizontal axis represents time t. Figure 9B The output voltage VO, load current ILOAD, and inductor currents of each phase (such as the first phase inductor current IL1, the second phase inductor current IL2, the third phase inductor current IL3, and the fourth phase inductor current IL4) are displayed sequentially from top to bottom, with the horizontal axis representing time t.

[0115] like Figure 9AThe diagram shows the relevant signal waveforms of a prior art multiphase power converter. At time t2, when the load current ILOAD suddenly drops, the existing control mechanism determines the number of operating phases of the power stage circuit based on the average current. However, because the phase switching decision in the prior art is based on the measurement and judgment of the average current, and is accompanied by an inherent delay (such as between time t2 and t3), the timing for actually shutting down the excess operating phases is significantly delayed. This causes the output voltage VO to experience a large overshoot and significant oscillation during the instantaneous period, requiring a longer time to return to a stable state.

[0116] In comparison, such as Figure 9B The diagram shows the relevant signal waveforms of a multiphase power converter according to an embodiment of the present invention. In this invention, after the load current ILOAD decreases at time t2, when the first-phase inductor current IL1 rapidly drops below the instantaneous current threshold ILth' at time t4, the instantaneous current response module immediately triggers the instantaneous current response, rapidly disabling all power stage circuits except the first-phase power stage circuit (i.e., disabling the second, third, and fourth-phase power stage circuits), retaining only a single phase (i.e., the first-phase power stage circuit) for continued operation. This real-time phase adjustment allows the output voltage VO to stabilize rapidly within a short instantaneous time, significantly reducing overshoot and output voltage oscillation amplitude during the instantaneous period.

[0117] In summary, compared with the prior art, the present invention effectively shortens the phase adjustment time of the power stage circuit through the instantaneous current response module and the instantaneous current threshold judgment mechanism, significantly improves the instantaneous response performance of the output voltage, suppresses the oscillation and overshoot of the output voltage, and greatly improves the system stability and reliability of the multiphase power converter.

[0118] Figure 10 This diagram illustrates an operation flowchart of a control method for a multiphase power converter according to an embodiment of the present invention. The control method controls a multiphase power converter comprising multiple power stage circuits, each coupled to an input voltage, and each controlling a corresponding inductor via at least one switch. The inductor transfers energy to the output voltage.

[0119] In this embodiment, the process begins in step S10, where the inductor current flowing through the inductor in each power stage circuit is sensed.

[0120] The next step is step S20, which involves averaging the inductor currents of multiple power stage circuits to generate an average current, for example, by using multiple low-pass filters and averaging circuits.

[0121] In step S30, the output voltage is sensed to understand the changes in the output voltage.

[0122] In step S40, the generated average current is compared with at least one preset average current threshold to determine the appropriate number of operating phases, thereby improving the overall conversion efficiency.

[0123] Next, proceed to step S50 to determine whether the change in output voltage exceeds a preset instantaneous voltage difference threshold. If so, proceed to step S51 to trigger an instantaneous voltage response, immediately adjust the number of operating phases to quickly suppress overshoot or undershoot of the output voltage, and return to step S10 after completing the instantaneous voltage response to continue the next round of control.

[0124] If the determination in step S50 is negative, the process proceeds to step S60 to further determine whether at least one inductor current exceeds a preset instantaneous current threshold. If yes, an instantaneous current response is triggered in step S61, adjusting the number of operating phases to maintain stability, and then returning to step S10. If the determination is negative, the process also directly returns to step S10, continuing current and voltage monitoring and control, so that when the load current changes, it can adaptively enter instantaneous voltage response, instantaneous current response, or determine the number of operating phases based on the average current.

[0125] Through the above-described cyclic control process, this invention can perform instantaneous voltage response, instantaneous current response, and efficiency-oriented phase regulation based on multiple conditions such as output voltage, inductor current, and average current, taking into account both conversion efficiency and output stability, and achieving the effect of dynamic load response and precise adjustment.

[0126] Figure 11 This diagram shows an embodiment of the instantaneous voltage response operation flowchart of the present invention, which corresponds to... Figure 10 The instantaneous voltage response operation described in step S51. This embodiment is used to specifically illustrate the instantaneous voltage response processing flow executed by the control circuit when the detected output voltage change exceeds an instantaneous voltage difference threshold.

[0127] In step S511, when the control circuit determines that the change in output voltage has exceeded a preset instantaneous voltage difference threshold, it triggers the instantaneous voltage response mechanism to respond to sudden changes in load demand in real time and prevent significant overshoot or undershoot of output voltage.

[0128] Following step S512, the control circuit drives all multiple power stage circuits to operate, or in another scenario, disables all multiple power stage circuits to operate, both for a preset period. This full-phase enable or full-phase disable method can adjust the overall power supply capacity or completely buffer and isolate the system in a very short time, effectively and quickly pulling the output voltage back to a stable range and suppressing instability.

[0129] After completing the transient voltage response, the process returns to Figure 10In step S10, the next round of current and voltage sensing and decision control process is restarted to continuously monitor the system operation and dynamically adjust the number of operating phases.

[0130] Figure 12 This diagram illustrates the instantaneous current response operation flowchart used in an embodiment of the present invention, which corresponds to... Figure 10 The instantaneous current response processing described in step S61. This embodiment is used to specifically illustrate the instantaneous current response action performed when the control circuit detects that the inductor current exceeds the instantaneous current threshold, and the change in output voltage does not exceed the instantaneous voltage difference threshold.

[0131] In step S611, when the current of at least one inductor exceeds the preset instantaneous current threshold, and the change in the output voltage has not yet reached the change amplitude required for the instantaneous voltage response, the control circuit triggers the instantaneous current response to effectively cope with the instantaneous demand generated by the output load and reduce the risk of voltage oscillation.

[0132] Following step S612, the control circuit will perform one of the following operations according to the system strategy: drive all multiple power stage circuits to operate to rapidly increase the available current supply capability, or disable all power stage circuits except one phase, keeping only one power stage circuit in operation and maintaining this state for a preset period of time, so as to reduce the magnitude of output voltage overshoot or undershoot by controlling the number of operating power stages, while suppressing voltage ringing caused by frequent phase switching.

[0133] After any of the above actions are completed, the process returns to Figure 10 In step S10, the inductor current sensing operation of each power stage circuit is repeated to further evaluate the current inductor current state and make the next round of control decisions.

[0134] This design provides a real-time adjustment mechanism between instantaneous voltage response and slow average current control, enabling the overall control system to more flexibly handle the disturbances to the output voltage caused by load changes during the transition period, thereby achieving better voltage regulation and power conversion efficiency.

[0135] In one embodiment, when the number of first operating phases determined based on at least one inductor current exceeding an instantaneous current threshold is inconsistent with the number of second operating phases determined based on the average current and an average current threshold, the first number of operating phases is used as the preferred number of operating phases to be executed. That is, executing the instantaneous current response takes precedence over executing the number of operating phases determined based on the average current and at least one average current threshold.

[0136] In one embodiment, performing a transient voltage response takes precedence over performing an operation phase number determined based on an average current and at least one average current threshold.

[0137] Figure 13 This illustrates the instantaneous current response triggering condition logic flow used in an embodiment of the present invention, which corresponds to... Figure 10 Further narrowing of the conditions in step S60 is used to illustrate an implementation of the application.

[0138] like Figure 13 As shown, in step S60', the control method performs the following logical judgment:

[0139] First, determine that the current inductor current is a positive inductor current;

[0140] Second, according to the average current response module, the current average current is less than the first average current threshold. In other words, the number of corresponding second operation phases is less than the first preset number (for example, the system may want to reduce the number of phases to one based on the average current).

[0141] Third, if it is confirmed that at least one inductor current exceeds the first instantaneous current threshold, it indicates that the instantaneous load may be too high, and the corresponding number of first operating phases may need to be increased to a second preset number or more (e.g., four phases or driving all of the multiple power stage circuits to operate).

[0142] Furthermore, this second preset quantity is greater than the first preset quantity, exhibiting a phase number difference.

[0143] If all the above conditions are "yes", then in step S61', the instantaneous current response is triggered. The instantaneous current response mechanism is prioritized, and the number of phases of the currently operating power stage is adjusted to avoid overshoot or undershoot of the output voltage due to slow average current calculation, and to improve the overall response speed and voltage regulation capability.

[0144] For example, if the average current determines that the operation should be reduced to one phase (i.e., the number of second operating phases = 1), but simultaneously the inductor current of one phase exceeds the instantaneous current threshold, indicating that the actual instantaneous current demand is too high, this invention prioritizes triggering the instantaneous current response, driving all power stage circuits to operate for a preset period to improve power supply capacity. If the conditions are not met, the process will return to normal. Figure 10 In step S10, the current detection cycle is repeated. Through this embodiment, the control method effectively avoids misjudging the load condition when setting the number of operating phases, further reducing the risk of voltage anomalies or system instability, and improving dynamic stability and conversion efficiency.

[0145] In the above embodiments, the scope can be further narrowed. If the average current is not less than the first average current threshold, and the number of operating phases is determined to be two or three phases, then even if the inductor current exceeds the first instantaneous current threshold, the instantaneous current response will not be triggered. In other words, the number of operating phases remains two or three phases as determined by the average current, rather than four phases or driving all of the multiple power stage circuits to operate.

[0146] Figure 14 This illustrates the instantaneous current response triggering condition logic flow used in an embodiment of the present invention, which corresponds to... Figure 10 Further narrowing of the conditions in step S60 illustrates an implementation of the application. This embodiment is similar to... Figure 13 Similar to the case where the inductor current is a negative inductor current.

[0147] like Figure 14 As shown, in step S60", the control method performs the following logical judgment:

[0148] First, confirm that the current inductor current is a negative inductor current, that is, energy is flowing back from the output terminal to the power stage circuit;

[0149] Second, determine that the average current is greater than the second average current threshold, and then determine the corresponding number of second operating phases (e.g., maintain four-phase operation).

[0150] Third, confirm that at least one phase inductor current exceeds the second instantaneous current threshold, indicating that the backflow current is too large, which can easily cause the output voltage VO to overshoot and oscillate.

[0151] At this time, the number of first operation phases is less than a fourth preset number, and the fourth preset number is less than a third preset number (corresponding to the number of second operation phases).

[0152] If all the above conditions are "yes", then proceed to step S61, triggering the instantaneous current response. The number of phases corresponding to the instantaneous current response is used as the priority operation basis for phase reduction control. Specifically, the control circuit can disable other power stage circuits except for one phase, and only retain one phase to operate continuously for a preset period of time, so as to quickly reduce the power supply energy and avoid large overshoot of output voltage and voltage regulation failure due to phase switching delay or slow average current response.

[0153] For example, if the average current corresponds to four-phase operation, but the inductor current is negative and the inductor current of a certain phase is lower than the -2 instantaneous current threshold (representing excessive reverse current), then the present invention can immediately trigger the instantaneous current response, switch to one-phase operation for a period of time, quickly eliminate excess energy, and suppress VO overshoot and voltage oscillation.

[0154] If the conditions are not met, the process will return. Figure 10Step S10: Re-execute the sensing and logic judgment process.

[0155] This embodiment improves voltage regulation under sudden load drops, avoids overshoot problems caused by continuous power supply from multiple phases, and enhances the dynamic stability and protection mechanism of the overall multiphase power converter.

[0156] In the above embodiments, the scope can be further narrowed. If the average current is not greater than the second average current threshold, and the number of operating phases is determined to be two or three phases (instead of maintaining four-phase operation), then even if the inductor current exceeds the second instantaneous current threshold, the instantaneous current response will not be triggered. In other words, the number of operating phases remains two or three phases as determined by the average current, rather than performing phase reduction control.

[0157] The present invention has been described above with reference to preferred embodiments. However, the above description is only intended to facilitate understanding of the invention by those skilled in the art and is not intended to limit the scope of the invention. The described embodiments are not limited to individual application and can also be used in combination. For example, two or more embodiments can be used in combination, and some components of one embodiment can be used to replace corresponding components in another embodiment. Furthermore, within the same spirit of the invention, those skilled in the art can conceive of various equivalent changes and combinations. For example, the present invention's statement of "processing or calculating based on a signal or generating an output result" is not limited to the signal itself, but also includes, when necessary, performing voltage-to-current conversion, current-to-voltage conversion, and / or proportional conversion on the signal, and then processing or calculating based on the converted signal to generate an output result. For example, Figure 2 , Figure 3 , Figure 4 and Figure 9B Multiphase power converters typically include four-phase power stage circuits, but the power stage circuits according to the present invention are not limited to four-phase power stage circuits. The present invention can be applied to any power stage circuit that has two or more phases. Therefore, under the same spirit of the present invention, those skilled in the art can conceive of various equivalent variations and combinations, many of which will not be listed here. Thus, the scope of the present invention should cover the above and all other equivalent variations.

Claims

1. A multiphase power converter, comprising: Multiple power stage circuits are used to convert an input voltage into an output voltage, wherein the multiple power stage circuits are respectively coupled to the input voltage and each of them controls a corresponding inductor through at least one switch, the inductor transferring energy to the output voltage; A current sensing circuit is coupled to the plurality of power stage circuits to sense an inductor current flowing through the inductor in each power stage circuit. as well as A control circuit includes an instantaneous current response module for triggering an instantaneous current response when at least one of the inductor currents exceeds an instantaneous current threshold, thereby increasing or decreasing the number of operating phases of the plurality of power stage circuits, thereby suppressing overshoot or undershoot of the output voltage.

2. The multiphase power converter as described in claim 1, wherein, Also includes: An average current circuit, coupled to the plurality of power stage circuits, is used to average the multiple inductor currents of the plurality of power stage circuits to generate an average current. The control circuit also includes an average current response module, which determines the number of operating phases based on the average current and at least one average current threshold, thereby improving a conversion efficiency.

3. The multiphase power converter as described in claim 2, wherein, Also includes: An output voltage sensing circuit, coupled to the plurality of power stage circuits, is used to sense the output voltage; The control circuit also includes an instantaneous voltage response module, which triggers an instantaneous voltage response when the change in the output voltage exceeds an instantaneous voltage difference threshold, thereby increasing or decreasing the number of operating phases and suppressing overshoot or undershoot of the output voltage.

4. The multiphase power converter as described in claim 3, wherein, During the instantaneous voltage response, the instantaneous voltage response module drives all of the plurality of power stage circuits to operate or deactivate all of the plurality of power stage circuits for a preset period.

5. The multiphase power converter as described in claim 2, wherein, The average current circuit includes multiple low-pass filters corresponding to the multiple power stage circuits to low-pass filter the multiple inductor currents to obtain the average current.

6. The multiphase power converter as described in claim 1, wherein, The current sensing circuit includes: A forward inductor current sensing circuit is used to sense a forward inductor current in each power stage circuit; and / or A negative inductor current sensing circuit is used to sense a negative inductor current in the inductor current of each power stage circuit. The instantaneous current response module is used to trigger the instantaneous current response when at least one of the positive inductor currents exceeds an instantaneous positive current threshold and / or at least one of the negative inductor currents exceeds an instantaneous negative current threshold, so as to increase or decrease the number of operating phases.

7. The multiphase power converter as described in claim 1, wherein, In the instantaneous current response, the instantaneous current response module drives all of the plurality of power stage circuits to operate, or disables all power stage circuits except one of the phases, keeping only one phase power stage circuit in operation for a preset period of time to suppress overshoot or undershoot of the output voltage.

8. The multiphase power converter as described in claim 2, wherein, The instantaneous current threshold is higher than the at least one average current threshold.

9. The multiphase power converter as claimed in claim 1, wherein, When the control circuit reduces the number of operating phases, it maintains one of the upper or lower bridge switches of the at least one switch of the power stage circuit in the off operation for a moment, so that the corresponding inductor current flows through the integrated diode of the upper or lower bridge switch, thereby increasing the absolute value of the inductor's voltage across the diode and shortening the moment.

10. A control method for controlling a multiphase power converter, wherein the multiphase power converter includes a plurality of power stage circuits for converting an input voltage into an output voltage, wherein the plurality of power stage circuits are respectively coupled to the input voltage and each controls a corresponding inductor through at least one switch, the inductor transferring energy to the output voltage, the control method comprising: Sensing the inductor current flowing through the inductor in each power stage circuit; and When at least one of the inductor currents exceeds a momentary current threshold, a momentary current response is triggered to increase or decrease the number of operating phases of the plurality of power stage circuits, thereby suppressing overshoot or undershoot of the output voltage.

11. The control method as described in claim 10, wherein, Also includes: Average the inductor currents of the multiple power stage circuits to generate an average current; and The number of operating phases is determined based on the average current and at least one average current threshold, thereby improving a conversion efficiency.

12. The control method as described in claim 11, wherein, Also includes: Sensing the output voltage; and When the change in the output voltage exceeds a momentary voltage difference threshold, a momentary voltage response is triggered to increase or decrease the number of operating phases, thereby suppressing overshoot or undershoot of the output voltage.

13. The control method as described in claim 12, wherein, The step of triggering an instantaneous voltage response when the change in the output voltage exceeds an instantaneous voltage difference threshold to increase or decrease the number of operating phases, thereby suppressing overshoot or undershoot of the output voltage, further includes: driving all of the plurality of power stage circuits to operate or deactivating all of the plurality of power stage circuits for a preset period during the instantaneous voltage response.

14. The control method as described in claim 11, wherein, The step of averaging the multiple inductor currents of the multiple power stage circuits to generate an average current includes: The multiple inductor currents are low-pass filtered to obtain the average current.

15. The control method as described in claim 10, wherein, The step of sensing the inductor current flowing through the inductor in each power stage circuit includes: A forward inductor current is sensed in the inductor current of each power stage circuit; and / or Sensing a negative inductor current of the inductor current in each power stage circuit; The instantaneous current response is triggered when at least one of the positive inductor currents exceeds an instantaneous positive current threshold and / or at least one of the negative inductor currents exceeds an instantaneous negative current threshold, thereby increasing or decreasing the number of operating phases.

16. The control method as described in claim 10, wherein, The step of triggering a transient current response when at least one of the inductor currents exceeds a transient current threshold, thereby increasing or decreasing the number of operating phases of the plurality of power stage circuits to suppress overshoot or undershoot of the output voltage, further includes: In response to the instantaneous current, all of the multiple power stage circuits are driven to operate, or all power stage circuits except one of the phases are disabled, leaving only one power stage circuit to operate for a preset period of time to suppress overshoot or undershoot of the output voltage.

17. The control method as described in claim 11, wherein, The instantaneous current threshold is higher than the at least one average current threshold.

18. The control method as described in claim 10, wherein, When reducing the number of operation phases, one of the upper or lower bridge switches of the at least one switch of the power stage circuit in the off operation is kept in operation for a moment, so that the corresponding inductor current flows through the integrated diode of the upper or lower bridge switch, thereby increasing the absolute value of the inductor's voltage across the circuit and shortening the moment.

19. A control method for controlling a multiphase power converter, wherein the multiphase power converter includes a plurality of power stage circuits for converting an input voltage into an output voltage, wherein the plurality of power stage circuits are respectively coupled to the input voltage and each controls a corresponding inductor through at least one switch, the inductor transferring energy to the output voltage, the control method comprising: Sensing the inductor current flowing through the inductor in each power stage circuit; The multiple inductor currents of the multiple power stage circuits are averaged to generate an average current. The output voltage is sensed; The number of operating phases is determined based on the average current and at least one average current threshold, thereby improving a conversion efficiency. When the change in the output voltage exceeds a momentary voltage difference threshold, a momentary voltage response is triggered to increase or decrease the number of operating phases of the multiple power stage circuits, thereby suppressing overshoot or undershoot of the output voltage. as well as When the change in the output voltage does not exceed the instantaneous voltage difference threshold, and when at least one of the inductor currents exceeds an instantaneous current threshold, an instantaneous current response is triggered to increase or decrease the number of operating phases, thereby suppressing overshoot or undershoot of the output voltage.

20. The control method as described in claim 19, wherein, It also includes: during the instantaneous voltage response, driving all of the plurality of power stage circuits to operate or deactivating all of the plurality of power stage circuits for a preset period.

21. The control method as described in claim 19, wherein, It also includes: in the instantaneous current response, driving all of the plurality of power stage circuits to operate, or disabling all power stage circuits except one of the phases, and keeping only one phase power stage circuit in operation for a preset period of time to suppress overshoot or undershoot of the output voltage.

22. The control method as described in claim 19, wherein, When a first number of operating phases determined based on at least one inductor current exceeding the instantaneous current threshold is inconsistent with a second number of operating phases determined based on the average current and the average current threshold, the first number of operating phases shall be used as the number of operating phases to be executed first.

23. The control method as described in claim 22, wherein, When the number of the second operating phases is less than a first preset number, the inductor current is a positive inductor current; when the number of the first operating phases is greater than a second preset number, and the second preset number is greater than the first preset number. Or, in which the number of the second operating phases is greater than a third preset number, the inductor current is a negative inductor current, the number of the first operating phases is less than a fourth preset number, and the fourth preset number is less than the third preset number.

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