Multi-phase power supply and its multi-phase controller, control method

Abstract

This application provides a multiphase power supply, its multiphase controller, and control method. The multiphase controller includes a sampling processing circuit that generates a sampled output signal based on the average inductance current of the multiphase power supply, and an output feedback compensation circuit that generates a feedback compensation signal based on the sampled output signal and the output feedback signal. When the load of the multiphase power supply undergoes transient changes, the sampling processing circuit can limit the maximum value of the sampled output signal, thereby controlling the output voltage of the multiphase power supply to always remain within a preset voltage range. This effectively avoids the output voltage from dropping above the target value due to excessive short-term load current under large load fluctuations, without affecting the speed of output voltage adjustment.

Description

Technical Field

[0001] This application relates to the field of multiphase power supply technology, specifically to a multiphase power supply and its multiphase controller and control method. Background Technology

[0002] Currently, power supplies for electronic devices, such as central processing units (CPUs), typically implement load-line (LL) control, sometimes called active voltage positioning (AVP), to meet transient response requirements. This establishes a linear relationship between the power supply's output voltage and load current. When the load current increases, the output voltage decreases linearly; when the load current decreases, the output voltage increases linearly. This effectively reduces voltage overshoot and undershoot during load transitions, ensuring that the output voltage remains within a predetermined voltage range (such as the specified range).

[0003] However, in practical applications, taking a multiphase power supply with a buck topology as an example, refer to... Figure 2 Under heavy load conditions, if the load of the multiphase power supply changes drastically at time t1, the output current Iout of the multiphase power supply will often exceed the maximum rated output current ICC_MAX (i.e., the target output current) in a short period of time after the load change. At this time, according to the load-line control, the output voltage Vout will drop below the target value Vout2, and may even cause the output voltage Vout to drop out of the predetermined voltage range (such as the spec range). That is, the minimum value of the output voltage Vout is lower than the lower limit value Vspec_min of the spec range, which will cause the main chip to malfunction. Summary of the Invention

[0004] In view of the above-mentioned technical problems, the purpose of this application is to provide a multiphase power supply and its multiphase controller and control method, wherein when the load of the multiphase power supply undergoes a transient change, the maximum value of the sampled output signal generated based on the average inductance current of the multiphase power supply is limited to not exceeding a preset first threshold. This allows the output voltage of the multiphase power supply to always remain within a preset voltage range without affecting the adjustment speed of the output voltage, effectively preventing the output voltage from dropping out of the preset voltage range due to excessive short-term load current under large load changes.

[0005] According to a first aspect of this application, a multiphase controller for a multiphase power supply is provided, the multiphase power supply including an N-phase power conversion circuit, where N is an integer greater than or equal to 1, wherein the multiphase controller includes:

[0006] The sampling processing circuit generates a sampling output signal based on the average inductor current of the multiphase power supply.

[0007] An output feedback compensation circuit receives the sampled output signal and generates a feedback compensation signal based on the sampled output signal and an output feedback signal characterizing the output voltage of the multiphase power supply. The multiphase controller generates a control signal for the N-phase power conversion circuit based on the feedback compensation signal and a reference voltage.

[0008] The sampling processing circuit is further configured to control the output voltage within a preset voltage range by limiting the maximum value of the sampled output signal when the load of the multiphase power supply undergoes a transient change.

[0009] Optionally, during the transient change of increased load, the average inductor current increases, and during the increase of the average inductor current, the sampled output signal first increases with the average inductor current, and then is clamped to a constant value.

[0010] Optionally, when the load of the multiphase power supply undergoes a transient change, the sampling processing circuit limits the maximum value of the sampled output signal to no more than a first threshold. When the sampled output signal is at the first threshold, it indicates that the average inductor current has increased to a first current threshold. When the average inductor current exceeds the first current threshold, the output voltage drops out of a preset voltage range.

[0011] Optionally, the average inductor current increases during transient changes in load.

[0012] During the period when the average inductor current is less than a preset current, the sampled output signal increases following the increase of the average inductor current;

[0013] When the average inductor current is greater than a preset current, the sampled output signal is clamped to a constant value.

[0014] Optionally, the preset current is less than or equal to a first current threshold, wherein the output voltage drops out of the preset voltage range when the average inductor current exceeds the first current threshold.

[0015] Optionally, when the average inductor current increases to the preset current, the sampling processing circuit clamps the sampling output signal to a second threshold. When the sampling output signal is at the second threshold, it indicates that the average inductor current is equal to the preset current.

[0016] Optionally, when the average inductor current increases to the preset current, the sampling processing circuit clamps the sampling output signal to a second threshold, and when the sampling output signal is at a third threshold, it indicates that the average inductor current is equal to the preset current.

[0017] Optionally, the multiphase power supply enters a steady state after the transient change in the load ends, and in the steady state, the average inductor current is equal to the preset current.

[0018] Optionally, the sampling processing circuit includes:

[0019] The sampling and averaging unit samples the inductor current of each phase power conversion circuit in the N-phase power conversion circuit to obtain N sampling signals, and performs averaging processing on the N sampling signals to obtain an average inductor current sampling signal that characterizes the average inductor current.

[0020] The switching unit has a first input terminal that receives the average inductor current sampling signal, a second input terminal that receives the second threshold, and an output terminal that is connected to the input terminal of the output feedback compensation circuit. The switching unit is used to output the average inductor current sampling signal when the average inductor current is less than the preset current, and to output the second threshold when the average inductor current is greater than the preset current.

[0021] Optionally, the sampling processing circuit further includes:

[0022] The sample-and-hold unit samples and holds the second threshold when the average inductor current is greater than the preset current.

[0023] Optionally, the sampling processing circuit includes:

[0024] The sampling and averaging unit samples the inductor current of each phase power conversion circuit in the N-phase power conversion circuit to obtain N sampling signals, and performs averaging processing on the N sampling signals to output an average inductor current sampling signal that represents the average inductor current.

[0025] The switching unit receives the average inductor current sampling signal at its input terminal and is connected to the input terminal of the output feedback compensation circuit at its output terminal. The switching unit is used to be in an on state when the average inductor current is less than the preset current and in an off state when the average inductor current is greater than the preset current.

[0026] The sample-and-hold unit holds the average inductor current sample signal received at the moment of shutdown when the switching unit is in the off state.

[0027] Optionally, the maximum value of the sampled output signal is positively correlated with the maximum drop in the output voltage.

[0028] According to a second aspect of this application, a multiphase power supply is provided, comprising:

[0029] An N-phase parallel coupled power conversion circuit, wherein each phase power conversion circuit has an input terminal coupled to the input voltage and an output terminal coupled to the load to provide power output, where N is an integer greater than or equal to 1;

[0030] As disclosed in any embodiment of this application, the multiphase controller is coupled to an N-phase power conversion circuit to provide control signals to the power switching transistors in the N-phase power conversion circuit.

[0031] According to a third aspect of this application, a control method for a multiphase power supply is provided, the multiphase power supply including an N-phase power conversion circuit, where N is an integer greater than or equal to 1, wherein the control method includes:

[0032] A sampling output signal is generated based on the average inductor current of the multiphase power supply;

[0033] A feedback compensation signal is generated based on the sampled output signal and the output feedback signal characterizing the output voltage of the multiphase power supply.

[0034] The control signal for the N-phase power conversion circuit is generated based on the feedback compensation signal and the reference voltage.

[0035] Specifically, when the load of the multiphase power supply undergoes a transient change, the output voltage is controlled to be within a preset voltage range by limiting the maximum value of the sampled output signal.

[0036] The beneficial effects of this application include at least the following:

[0037] The multiphase power supply, its controller, and control method provided in this application include a sampling processing circuit that generates a sampling output signal based on the average inductor current of the multiphase power supply, and an output feedback compensation circuit that generates a feedback compensation signal based on the sampling output signal and the output feedback signal. When the load of the multiphase power supply undergoes transient changes, the maximum value of the sampling output signal is limited to control the output voltage to remain within a preset voltage range. Compared with existing solutions, this application does not require filtering the average inductor current with a larger time constant, thus eliminating the introduction of delay. This allows the output voltage of the multiphase power supply to remain within the preset voltage range without affecting the adjustment speed of the output voltage, effectively preventing the output voltage from dropping above the target value due to excessive short-term load current during large load transitions.

[0038] It should be noted that the above general description and the following detailed description are merely exemplary and explanatory, and do not limit this application. Attached Figure Description

[0039] Figure 1 A schematic diagram illustrating an embodiment of a multiphase power supply provided according to an embodiment of this application is shown;

[0040] Figure 2 The diagram shows the waveforms of some signals from a multiphase power supply in the relevant technology.

[0041] Figure 3 This diagram shows a schematic representation of the sampling processing circuit provided according to the first embodiment of this application.

[0042] Figure 4 A schematic diagram of the sampling processing circuit provided according to the second embodiment of this application is shown;

[0043] Figure 5a and Figure 5b The following are schematic diagrams showing waveforms of partial signals from a multiphase power supply according to different embodiments of this application;

[0044] Figure 6 A flowchart illustrating a control method for a multiphase power supply according to an embodiment of this application is shown. Detailed Implementation

[0045] The preferred embodiments of this disclosure are described in detail below with reference to the accompanying drawings, but this disclosure is not limited to these embodiments. This disclosure covers any alternatives, modifications, equivalent methods, and solutions made within the spirit and scope of this disclosure.

[0046] In order to provide the public with a thorough understanding of this disclosure, specific details are described in detail in the following preferred embodiments of this disclosure, but those skilled in the art can fully understand this disclosure without these details.

[0047] The present disclosure is described in more detail below by way of example with reference to the accompanying drawings. It should be noted that the drawings are in a simplified form and use non-precise scales, and are only used to facilitate and clarify the illustration of the embodiments of the present disclosure.

[0048] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application may be implemented in various forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of this application.

[0049] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0050] In the description of this application, words such as "exemplary" or "for example" are used to indicate that they are examples, illustrations, or descriptions. Any embodiment described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments. The term "and / or" in this document describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. "Multiple" refers to two or more. Furthermore, to facilitate a clear description of the technical solutions of the embodiments of this application, the terms "first," "second," etc., are used to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first," "second," etc., do not limit the quantity or execution order, and that "first," "second," etc., do not necessarily imply differences.

[0051] In addition, the same reference numerals in the figures indicate the same or similar structures, so repeated descriptions of them will be omitted. That is, the various parts in this specification are described in a combination of parallel and progressive manner. Each part focuses on the differences from other parts, and the same or similar parts between the various parts can be referred to each other.

[0052] Figure 1 A schematic diagram of an embodiment of the multiphase power supply provided in this application is shown.

[0053] like Figure 1 As shown, the multiphase power supply 100 includes: N-phase parallel coupled power conversion circuits 111-11N, a multiphase power supply controller (hereinafter referred to as multiphase controller) 120, and a feedback circuit 130, where N is an integer greater than or equal to 1.

[0054] Each phase of the N-phase power conversion circuits 111-11N has an input terminal coupled to the input voltage Vin and an output terminal coupled to the load to provide power output. Each phase power conversion circuit includes a drive unit, power switches T1 and T2, and an inductor Lx. Power switches T1 and T2 are connected between the input voltage Vin and a reference ground. The first end of the inductor Lx is connected to the midpoint between power switches T1 and T2, and the second end is connected to the first end of the output capacitor Cout. The second end of the output capacitor Cout is grounded. The drive unit in each phase power conversion circuit 111-11N receives control signals (pulse width modulation signals PWM1-PWMN) from the multi-phase controller 120, and controls the corresponding power switch to turn on and off according to the received control signals, charging the energy storage element of that phase for a corresponding duration to generate the output voltage of that phase. At the same time, the inductor current I in each phase power conversion circuit... L1 -I LN The current is combined into an average inductor current Iavg, and the output voltage Vout is generated based on the output capacitance Cout to drive the load.

[0055] It should be noted that, Figure 1 Although the power conversion circuit shown is described as having a buck topology, the technical solution of the present invention can be adopted for any type of layout design, such as boost, flyback, buck-boost, Cuk, Sepic, and Zeta.

[0056] The feedback circuit 130 is used to sample the output voltage Vout of the multiphase power supply 100 to obtain the output feedback signal VFB0.

[0057] The multiphase controller 120 is coupled to the N-phase power conversion circuits 111-11N respectively, and is used to determine the inductor current I of each phase power conversion circuit in the N-phase power conversion circuits 111-11N. L1 -I LN (or its sampling results) and the output feedback signal VFB0 provide control signals PWM1-PWMN to each power switch in the N-phase power conversion circuit 111-11N.

[0058] The multiphase controller 120 further includes: a sampling processing circuit 121, an output feedback compensation circuit 122, a reference voltage generation circuit 123, an error amplification circuit 124, and a control signal generation circuit 125.

[0059] Sampling processing circuit 121 calculates the inductor current I of each phase power conversion circuit in the N-phase power conversion circuit 111-11N. L1 -ILN (Or, receive the inductor current I for each phase power conversion circuit) L1 -I LN The sampling output signal Vavg_clamp is generated from the sampled signal. The output feedback compensation circuit 122 receives the output feedback signal VFB0 and the sampled output signal Vavg_clamp output by the sampling processing circuit 121, and adjusts the output feedback signal VFB0 according to the received sampled output signal Vavg_clamp to obtain the feedback compensation signal VFB1. The reference voltage generation circuit 123 uses the reference voltage Vref. The error amplifier circuit 124 amplifies the error of the feedback compensation signal VFB1 and the reference voltage Vref to generate the error amplified signal Vc. The control signal generation circuit 125 obtains the control signals PWM1-PWMN for each phase power conversion circuit based on the error amplified signal Vc.

[0060] It can be understood that the output feedback compensation circuit 122 mainly generates a compensation voltage (denoted as Vdroop) based on the product of the received sampled output signal and the load line impedance, and obtains the feedback compensation signal VFB1 by adding the compensation voltage Vdroop and the output feedback signal VFB0, i.e., VFB1 = VFB0 + Vdroop. The maximum value of the sampled output signal Vavg_clamp output by the sampling processing circuit 121 is positively correlated with the maximum drop in the output voltage Vout.

[0061] When the load of the multiphase power supply 100 undergoes transient changes, in some related technical solutions, the multiphase controller 120 is often set to filter the average inductor current with a larger time constant in order to reduce the impact of short-term large load current on the output voltage Vout. However, the disadvantage is that it introduces a delay, which affects the adjustment speed of the output voltage.

[0062] In this embodiment, when a transient change in the load of the multiphase power supply 100 is detected, the sampling processing circuit 121 limits the maximum value of the sampled output signal Vavg_clamp from the output to the output feedback compensation circuit 122, thereby controlling the output voltage Vout to be within a preset voltage range. This preset voltage range can be any voltage range, including but not limited to the spec range.

[0063] During transient load increases, the average inductor current Iavg of the multiphase power supply 100 increases. In existing solutions, the average inductor current sampling signal Vavg used to compensate for the output voltage Vout increases along with the average inductor current Iavg, exceeding the maximum allowable threshold, causing the output voltage Vout to drop out of the preset voltage range. In this application, although the average inductor current Iavg of the multiphase power supply 100 increases during transient load increases, the sampling output signal Vavg_clamp output by the sampling processing circuit 121 for compensating the output voltage Vout increases to a certain level along with the average inductor current Iavg and is then clamped to a constant value, preventing it from exceeding the maximum allowable threshold. Therefore, the sampling output signal Vavg_clamp does not increase beyond the preset first threshold (e.g., V1), thus preventing the output voltage Vout from dropping out of the preset voltage range.

[0064] Specifically, in this embodiment, when the load of the multiphase power supply 100 undergoes a transient change, the sampling processing circuit 121 is specifically configured to limit the maximum value of the sampling output signal Vavg_clamp to no more than a first threshold V1. When the sampling output signal Vavg_clamp is at the first threshold V1, it indicates that the average inductor current Iavg has increased to the first current threshold, and the output voltage Vout will drop out of the preset voltage range when the average inductor current Iavg exceeds the first current threshold.

[0065] Furthermore, in this embodiment, during the transient change of increased load, as the average inductor current Iavg of the multiphase power supply 100 increases, before the average inductor current Iavg of the multiphase power supply 100 increases to the preset current (i.e., during the period when the average inductor current Iavg is less than the preset current), the sampling output signal Vavg_clamp output by the sampling processing circuit 121 will increase along with the increase of the average inductor current Iavg; while when the average inductor current Iavg of the multiphase power supply 100 is greater than the preset current, the sampling output signal Vavg_clamp output by the sampling processing circuit 121 will be clamped to a constant value, and when the output feedback compensation circuit 122 adjusts the output feedback signal VFB0 based on this constant value, the output voltage Vout will not drop out of the preset voltage range, that is, the minimum value of the output voltage Vout during the transient change of increased load will still be greater than or equal to the lower limit of the preset voltage range (denoted as Vspec_min), effectively avoiding the situation where the output voltage Vout drops out of the predetermined voltage range. The aforementioned preset current can be set to any value less than or equal to the first current threshold, and the aforementioned constant value can be set to any value less than or equal to the first threshold V1.

[0066] It is understood that when the average inductor current Iavg is less than the preset current, the sampling output signal Vavg_clamp output by the sampling processing circuit 121 represents the real-time average inductor current information. For example, after the transient change in the load ends and the system returns to steady state, the output feedback compensation circuit 122 will generate a feedback compensation signal VFB1 based on the real-time average inductor current information and the output feedback signal VFB0. In some preferred embodiments, the preset current can be set to satisfy the following condition: when the load enters a steady state after the transient change ends, the average inductor current Iavg in the steady state (i.e., the expected average inductor current Iavg after the load change) is equal to the preset current, so that the output voltage Vout can be maintained at the expected target value during the transient change of the load of the multiphase power supply 100.

[0067] In some embodiments, when the average inductor current Iavg increases to a preset current, the sampling processing circuit 121 clamps the sampling output signal Vavg_clamp to a second threshold less than or equal to the first threshold V1. When the sampling output signal Vavg_clamp is at a third threshold, it indicates that the average inductor current Iavg is equal to the preset current. If a voltage signal (such as the average inductor current sampling signal Vavg) is used to characterize the average inductor current Iavg, then in these embodiments, the average inductor current sampling signal Vavg corresponding to the increase of the average inductor current Iavg to the preset current is the third threshold, which can be used to characterize the preset current. This third threshold can be greater than the second threshold or less than the second threshold.

[0068] For example, refer to Figure 3 , Figure 3 A schematic diagram of the sampling processing circuit in the first embodiment of this application is shown. Figure 3 As shown, in this embodiment, the sampling processing circuit 121 specifically includes: a sampling and averaging unit 310, a switching unit 320, a comparator 330, and a sample-and-hold unit 340.

[0069] The sampling and averaging unit 310 is used to measure the inductor current I of each phase power conversion circuit in the N-phase power conversion circuits 111-11N. L1 -I LN N sampling signals are obtained by sampling, and the average of the N sampling signals is processed to obtain the average inductor current sampling signal Vavg, which represents the average inductor current Iavg of the multiphase power supply 100. Figure 3In the sampling and averaging unit 310, for example, N sampling resistors Rcs1-RcsN and a capacitor C1 are included. The first terminals of the N sampling resistors Rcs1-RcsN are respectively connected to the inductors in the corresponding phase power conversion circuits. The second terminals of the N sampling resistors Rcs1-RcsN are all connected to the first terminal of the capacitor C1, and the second terminal of the capacitor C1 is connected to the reference ground. The sampling and averaging unit 310 measures the inductor current I of each phase power conversion circuit in the N-phase power conversion circuits 111-11N through the N sampling resistors Rcs1-RcsN. L1 -I LN Sampling is performed, and the average of the N sampled signals is achieved based on capacitor C1. Optionally, the N sampling resistors Rcs1-RcsN can also be set outside the sampling and averaging unit 310, in which case the sampling and averaging unit 310 directly receives the N sampled signals.

[0070] The first input terminal of the switching unit 320 receives the average inductor current sampling signal Vavg, the second input terminal of the switching unit 320 receives the voltage signal Vset2, the control terminal of the switching unit 320 receives a selection signal, and the output terminal of the switching unit 320 is connected to the input terminal of the output feedback compensation circuit 122. The switching unit 320 is used to output one of the average inductor current sampling signal Vavg and the voltage signal Vset2 according to the selection signal. Figure 3 In the circuit, the switching unit 320 includes a switch S1 and a switch S2. The first end of the switch S1 is connected to the output end of the sampling and averaging unit 310 (i.e., the first end of the capacitor C1). The second end of the switch S1 is connected to the output end of the switching unit 320 and the input end of the output feedback compensation circuit 122. The first end of the switch S2 receives the voltage signal Vset2. The second end of the switch S2 is connected to the output end of the switching unit 320 and the input end of the output feedback compensation circuit 122. The control end of the switch S1 receives the inverted signal of the selection signal through the inverter 321. The control end of the switch S2 receives the selection signal.

[0071] The first input terminal of comparator 330 receives the average inductor current sampling signal Vavg, and the second input terminal of comparator 330 receives the voltage signal Vset1. Comparator 330 determines whether the average inductor current Iavg is greater than the preset current by comparing the average inductor current sampling signal Vavg and the voltage signal Vset1, and generates a selection signal based on the comparison result and outputs it to the control terminal of the switching unit 320.

[0072] In some embodiments, voltage signal Vset1 is a third threshold and voltage signal Vset2 is a second threshold; in this case, voltage signals Vset1 and Vset2 are of unequal magnitude. Of course, in other embodiments, voltage signals Vset1 and Vset2 can also be set to be of equal magnitude.

[0073] The sample-and-hold unit 340 is connected to the output terminal of the switching unit 320 and the output terminal of the sampling processing circuit 121, and is used to obtain the sampled output signal Vavg_clamp through the sample-and-hold voltage signal Vset2 when the average inductor current Iavg is greater than the preset current. Figure 3 In this circuit, the sample-and-hold unit 340 includes a capacitor C2 connected between the output terminal of the sampling processing circuit 121 and a reference ground. In some other embodiments, the sample-and-hold unit 340 may be omitted, and the sampling processing circuit 121 directly uses the output signal of the switching unit 320 as the sampled output signal.

[0074] by Figure 3 Taking the circuit shown as an example, during operation, when the average inductor current sampling signal Vavg is greater than the voltage signal Vset1, the comparator 330 outputs a selection signal with a first level state (such as one of a high level state and a low level state), indicating that the average inductor current Vavg is greater than the preset current. Controlled by the selection signal of the first level state, switch S1 in the switching unit 320 is turned off and switch S2 is turned on, thereby selecting the output voltage signal Vset2. At this time, the sample and hold unit 340 performs sample and hold processing on the voltage signal Vset2 to obtain the sampled output signal Vavg_clamp. When the average inductor current sampling signal Vavg is less than the voltage signal Vset1, comparator 321 outputs a selection signal with a second level state (such as one of a high level state and a low level state), indicating that the average inductor current Iavg is less than a preset current. Controlled by the selection signal of the second level state, switch S1 in the switching unit 320 is turned on and switch S2 is turned off, thereby selecting the output of the average inductor current sampling signal Vavg, and outputting the average inductor current sampling signal Vavg as the sampling output signal Vavg_clamp, or the sampling and holding unit 340 filters the average inductor current sampling signal Vavg to obtain the sampling output signal Vavg_clamp.

[0075] In other embodiments, when the average inductor current Iavg increases to a preset current, the sampling processing circuit 121 clamps the sampling output signal Vavg_clamp to a second threshold less than or equal to the first threshold V1. When the sampling output signal Vavg_clamp is at the second threshold, it indicates that the average inductor current Iavg is equal to the preset current. If a voltage signal (such as the average inductor current sampling signal Vavg) is used to characterize the average inductor current Iavg, then in these embodiments, the average inductor current sampling signal Vavg corresponding to the increase of the average inductor current Iavg to the preset current is also equal to the second threshold; that is, the second threshold can be used to characterize the preset current.

[0076] For example, refer to Figure 4, Figure 4 A schematic diagram of the sampling processing circuit in the second embodiment of this application is shown. Figure 4 As shown, in this embodiment, the sampling processing circuit 121 specifically includes: a sampling and averaging unit 410, a switching unit 420, a comparator 430, and a sample and hold unit 440.

[0077] The sampling and averaging unit 410 is used to measure the inductor current I of each phase power conversion circuit in the N-phase power conversion circuits 111-11N. L1 -I LN N sampling signals are obtained by sampling, and the average value of the N sampling signals is processed to output the average inductor current sampling signal Vavg, which represents the average inductor current Iavg of the multiphase power supply 100. Figure 4 In the sampling and averaging unit 410, for example, N sampling resistors Rcs1-RcsN and a capacitor C1 are included. The first terminals of the N sampling resistors Rcs1-RcsN are respectively connected to the inductors in the corresponding phase power conversion circuits. The second terminals of the N sampling resistors Rcs1-RcsN are all connected to the first terminal of the capacitor C1, and the second terminal of the capacitor C1 is connected to the reference ground. The sampling and averaging unit 410 measures the inductor current I of each phase power conversion circuit in the N-phase power conversion circuits 111-11N through the N sampling resistors Rcs1-RcsN. L1 -I LN Sampling is performed, and the average of the N sampled signals is achieved based on capacitor C1. Optionally, the N sampling resistors Rcs1-RcsN can also be set outside the sampling and averaging unit 410, in which case the sampling and averaging unit 410 directly receives the N sampled signals.

[0078] The input terminal of the switching unit 420 receives the average inductor current sampling signal Vavg. The output terminal of the switching unit 420 is connected to the input terminal of the output feedback compensation circuit 122. The switching unit 420 is in a conducting state when the average inductor current Iavg is less than a preset current, so as to connect the transmission path of the average inductor current sampling signal Vavg to the input terminal of the output feedback compensation circuit 122. When the average inductor current Iavg is greater than the preset current, it is in a turning-off state, so as to disconnect the transmission path of the average inductor current sampling signal Vavg to the input terminal of the output feedback compensation circuit 122. Figure 4 In the middle, the switching unit 420 includes a switch S1. The first end of the switch S1 is connected to the output end of the sampling and averaging unit 410 (i.e., the first end of the capacitor C1). The second end of the switch S1 is connected to the output end of the switching unit 420 and the input end of the output feedback compensation circuit 122. The control end of the switch S1 receives the selection signal.

[0079] The first input terminal of comparator 430 receives the average inductor current sampling signal Vavg, and the second input terminal of comparator 430 receives the voltage signal Vset1. Comparator 430 determines whether the average inductor current Iavg is greater than the preset current by comparing the average inductor current sampling signal Vavg and the voltage signal Vset1, and generates a selection signal based on the comparison result.

[0080] In some embodiments, the voltage signal Vset1 is a second threshold. Of course, in other embodiments, the voltage signal Vset1 can also be any other threshold less than or equal to the first threshold V1.

[0081] The sample and hold unit 440 is connected to the output terminal of the switching unit 420 and is used to hold the average inductor current sampling signal Vavg received at the moment the switching unit 420 is turned off when the switching unit 420 is in the off state to obtain the sampled output signal Vavg_clamp. Figure 4 In the sample-and-hold unit 440, there is a capacitor C2 connected between the output of the sampling processing circuit 121 and the reference ground.

[0082] by Figure 4 Taking the circuit shown as an example, during operation, when the average inductor current sampling signal Vavg is less than the voltage signal Vset1, the comparator 430 outputs a selection signal with a first level state (such as one of a high level state and a low level state). Controlled by the selection signal of the first level state, the switch S1 in the switching unit 420 is turned on, thereby connecting the transmission path of the average inductor current sampling signal Vavg to the input terminal of the output feedback compensation circuit 122. At this time, the average inductor current sampling signal Vavg output by the sampling and averaging unit 410 can be directly used as the sampling output signal Vavg_clamp, or the sampling and holding unit 440 can filter the average inductor current sampling signal Vavg output by the sampling and averaging unit 410 to obtain the sampling output signal Vavg_clamp. When the average inductor current sampling signal Vavg is greater than the voltage signal Vset1, comparator 430 outputs a selection signal with a second level state (such as a high level state or a low level state). Controlled by this second level state selection signal, switch S1 in switching unit 420 is turned off, thereby disconnecting the transmission path of the average inductor current sampling signal Vavg to the input of the output feedback compensation circuit 122. At this time, sample-and-hold unit 560 performs sample-and-hold processing on the average inductor current sampling signal Vavg output by sampling processing circuit 410 at the moment the switching unit 420 is turned off to obtain the sampled output signal Vavg_clamp. It can be understood that sample-and-hold unit 560 can hold the sampled output signal Vavg_clamp at a voltage signal Vset1 that represents the preset current.

[0083] It should be noted that, Figure 3 and Figure 4 The illustration shows an implementation scheme for determining whether the average inductor current Iavg has increased to the preset current by comparing the average inductor current sampling signal Vavg, which characterizes the average inductor current Iavg of the multiphase power supply 100, and the voltage signal Vset1, which characterizes the preset current. In other embodiments, the magnitude relationship between the average inductor current Iavg and the preset current can also be directly compared by current comparison.

[0084] Figure 5a and Figure 5b The following are schematic diagrams showing waveforms of partial signals from a multiphase power supply according to different embodiments of this application.

[0085] Combination Figure 3 , Figure 4 and Figure 5b Assuming that the load of the multiphase power supply 100 undergoes a transient change at time t1, during this transient change, even if the output current Iout of the multiphase power supply exceeds the maximum allowable threshold, the sampled output signal Vavg_clamp output from the sampling processing circuit 121 to the output feedback compensation circuit 122 will still be clamped to below the first threshold V1, and will reach the voltage value V corresponding to the desired target average inductor current in the stable state after the transient change ends. ICC This ensures that after the output voltage Vout starts to drop from the initial value Vout1, its instantaneous minimum value during the transient change period will not fall below the lower limit of the predetermined voltage range Vspec_min. In other words, the output voltage Vout of the multiphase power supply 100 in this application can always be within the preset voltage range without affecting the adjustment speed of the output voltage Vout.

[0086] Where both voltage signals Vset2 and Vset1 are set to be equal to the voltage value V ICC In this case, during the transient changes in the load of the multiphase power supply 100, the output voltage Vout can also be maintained at the desired target value Vout2, such as... Figure 5a As shown, this effectively reduces the variation of the output voltage Vout when the load undergoes transient changes, which is beneficial to improving the output stability of the multiphase power supply 100.

[0087] Furthermore, this application also discloses a control method for a multiphase power supply, which can be applied to the multiphase power supply 100 shown in any of the foregoing embodiments. Specifically, as... Figure 6 As shown, the control method includes performing the following steps:

[0088] Step 610: Generate a sampling output signal based on the average inductance current of the multiphase power supply. When the load of the multiphase power supply undergoes a transient change, the maximum value of the sampling output signal is limited to control the output voltage within a preset voltage range.

[0089] Step 620: Generate a feedback compensation signal based on the sampled output signal and the output feedback signal characterizing the output voltage of the multiphase power supply.

[0090] Step 630: Generate control signals for the N-phase power conversion circuit based on the feedback compensation signal and the reference voltage.

[0091] It should be noted that the specific implementation of each step in the control method of the multiphase power supply described above and the technical effects that can be obtained can be found in the relevant description of the multiphase power supply and its multiphase controller in any of the foregoing embodiments, and will not be repeated here.

[0092] In summary, the multiphase power supply and its control scheme disclosed in this application, when detecting a transient change in the load of the multiphase power supply, limits the maximum value of the sampled output signal generated based on the average inductor current of the multiphase power supply to no more than a preset first threshold. This eliminates the need for filtering the average inductor current with a larger time constant, ensuring that the output voltage of the multiphase power supply remains within a preset voltage range. Since no delay is introduced, the adjustment speed of the output voltage is not affected, effectively preventing the output voltage from dropping above the target value due to excessive short-term load current under large load fluctuations. Simultaneously, it can quickly and accurately clamp the maximum value of the load current to a preset current.

[0093] Furthermore, it should be noted that the preset current setting conditions mentioned above are for the process where a large load causes the actual average inductor current to rise and the output voltage to fall, thus preventing the output voltage from falling below the lower voltage limit during the voltage drop period. However, in reality, the average inductor current will fall back to transition to a steady state in the later stages of the transient change. Therefore, it is necessary to consider that after the average inductor current falls back, the output feedback compensation circuit can receive the sampled output signal that follows the real-time change of the average inductor current. That is, after the protection against the output voltage falling below the lower limit ends, the multiphase controller controls the output of the multiphase power supply based on the real-time average inductor current. Therefore, a lower limit for the preset current needs to be set. Specifically, after the transient change and entering a steady state, the average inductor current in the steady state is the lower limit of the preset current, thus ensuring that the average inductor current can be detected falling back to the preset current during the transient change, and the feedback compensation circuit switches to generate a feedback compensation signal based on the real-time average inductor current and output voltage. Similarly, the above only limits the upper limit of the maximum value of the sampled output signal; in actual control, the lower limit of the maximum value of the sampled output signal can also be limited. Preferably, after the transient change, the system enters a steady state, and the sampled output signal corresponding to the average inductor current in the steady state in real time is the lower limit value of the sampled output signal.

[0094] Finally, it should be noted that the above embodiments are merely examples for clearly illustrating this application and are not intended to limit the implementation. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this application.

Claims

1. A multiphase controller for a multiphase power supply, the multiphase power supply comprising an N-phase power conversion circuit, where N is an integer greater than or equal to 1, wherein... The multiphase controller includes: The sampling processing circuit generates a sampling output signal based on the average inductor current of the multiphase power supply. An output feedback compensation circuit receives the sampled output signal and generates a feedback compensation signal based on the sampled output signal and an output feedback signal characterizing the output voltage of the multiphase power supply. The multiphase controller generates a control signal for the N-phase power conversion circuit based on the feedback compensation signal and a reference voltage. The sampling processing circuit is further configured to control the output voltage within a preset voltage range by limiting the maximum value of the sampled output signal when the load of the multiphase power supply undergoes a transient change.

2. The multiphase controller according to claim 1, wherein, During the transient change of increased load, the average inductor current increases, and during the period of increase of the average inductor current, the sampled output signal first increases with the average inductor current, and then is clamped to a constant value.

3. The multiphase controller according to claim 1, wherein, When the load of the multiphase power supply undergoes a transient change, the sampling processing circuit limits the maximum value of the sampled output signal to no more than a first threshold. When the sampled output signal is the first threshold, it indicates that the average inductor current has increased to a first current threshold. When the average inductor current exceeds the first current threshold, the output voltage drops out of a preset voltage range.

4. The multiphase controller according to claim 1 or 2, wherein, During the transient change of increased load, the average inductor current increases; During the period when the average inductor current is less than a preset current, the sampled output signal increases following the increase of the average inductor current; When the average inductor current is greater than a preset current, the sampled output signal is clamped to a constant value.

5. The multiphase controller according to claim 4, wherein, The preset current is less than or equal to a first current threshold, and the output voltage drops out of the preset voltage range when the average inductor current exceeds the first current threshold.

6. The multiphase controller according to claim 4, wherein, When the average inductor current increases to the preset current, the sampling processing circuit clamps the sampling output signal to a second threshold, and when the sampling output signal is the second threshold, it indicates that the average inductor current is equal to the preset current.

7. The multiphase controller according to claim 4, wherein, When the average inductor current increases to the preset current, the sampling processing circuit clamps the sampling output signal to a second threshold. When the sampling output signal is at a third threshold, it indicates that the average inductor current is equal to the preset current.

8. The multiphase controller according to any one of claims 5-7, wherein, After the transient change in the load ends, the multiphase power supply enters a steady state, and in the steady state, the average inductor current is equal to the preset current.

9. The multiphase controller according to claim 7, wherein, The sampling processing circuit includes: The sampling and averaging unit samples the inductor current of each phase power conversion circuit in the N-phase power conversion circuit to obtain N sampling signals, and performs averaging processing on the N sampling signals to obtain an average inductor current sampling signal that characterizes the average inductor current. The switching unit has a first input terminal that receives the average inductor current sampling signal, a second input terminal that receives the second threshold, and an output terminal that is connected to the input terminal of the output feedback compensation circuit. The switching unit is used to output the average inductor current sampling signal when the average inductor current is less than the preset current, and to output the second threshold when the average inductor current is greater than the preset current.

10. The multiphase controller according to claim 9, wherein, The sampling processing circuit further includes: The sample-and-hold unit samples and holds the second threshold when the average inductor current is greater than the preset current.

11. The multiphase controller according to claim 6, wherein, The sampling processing circuit includes: The sampling and averaging unit samples the inductor current of each phase power conversion circuit in the N-phase power conversion circuit to obtain N sampling signals, and performs averaging processing on the N sampling signals to output an average inductor current sampling signal that represents the average inductor current. The switching unit receives the average inductor current sampling signal at its input terminal and is connected to the input terminal of the output feedback compensation circuit at its output terminal. The switching unit is used to be in an on state when the average inductor current is less than the preset current and in an off state when the average inductor current is greater than the preset current. The sample-and-hold unit holds the average inductor current sample signal received at the moment of shutdown when the switching unit is in the off state.

12. The multiphase controller according to claim 1, wherein, The maximum value of the sampled output signal is positively correlated with the maximum drop in the output voltage.

13. A multiphase power supply, wherein, include: An N-phase parallel coupled power conversion circuit, wherein each phase power conversion circuit has an input terminal coupled to the input voltage and an output terminal coupled to the load to provide power output, where N is an integer greater than or equal to 1; The multiphase controller as described in any one of claims 1-12 is coupled to an N-phase power conversion circuit and is used to provide control signals to the power switching transistors in the N-phase power conversion circuit.

14. A control method for a multiphase power supply, the multiphase power supply comprising an N-phase power conversion circuit, where N is an integer greater than or equal to 1, wherein... The control method includes: A sampling output signal is generated based on the average inductor current of the multiphase power supply; A feedback compensation signal is generated based on the sampled output signal and the output feedback signal characterizing the output voltage of the multiphase power supply. The control signal for the N-phase power conversion circuit is generated based on the feedback compensation signal and the reference voltage. Specifically, when the load of the multiphase power supply undergoes a transient change, the output voltage is controlled to be within a preset voltage range by limiting the maximum value of the sampled output signal.

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