A multiple-inductance multiple-output dc voltage converter and a control method thereof

Abstract

This application discloses a multi-inductor multi-output DC-DC voltage converter and its control method. The converter includes several basic unit modules and a charge redistribution module. The basic unit modules are connected in series and all are connected to the charge redistribution module. The method includes: based on the input voltage signal, and using the basic unit modules, sequentially and alternately magnetizing and demagnetizing a first inductor within a complete cycle to obtain the load-side output current and load-side output voltage; obtaining the first flying capacitor current and combining it with the load-side output current and load-side output voltage; and adjusting the inductor current based on the charge redistribution module to output the adjusted inductor current. The embodiments of this application enhance the ability to support higher input voltages and more output channels while reducing external components, thereby improving system conversion efficiency. This application can be widely applied to integrated circuit design technology.

Description

Technical Field

[0001] This application relates to the field of integrated circuit design technology, and in particular to a multi-inductor multi-output DC voltage converter and its control method. Background Technology

[0002] Traditional inductor-based buck converter architectures face challenges in high voltage conversion ratio applications, including increased control stage design complexity, larger size, and decreased efficiency. A high voltage conversion ratio typically implies a more extreme duty cycle (D, defined as V). OUT / V IN This increases the difficulty of control. Simultaneously, the power switch needs to withstand high voltage stress, thus requiring the use of high-voltage transistors. However, high-voltage transistors exhibit large parasitic effects and poor FoM (Figures of Merit) values, degrading efficiency. Furthermore, the switching node V... SW The large voltage swing generates a large current ripple, which forces the use of inductors with larger inductance values, thereby increasing the DC resistance (DCR) of the inductor and further increasing the size of passive components.

[0003] In summary, the technical problems existing in the relevant technologies need to be improved. Summary of the Invention

[0004] The main objective of this application is to propose a multi-inductor multi-output DC voltage converter and its control method, which can enhance the ability to support higher input voltages and more output channels and reduce external components, thereby improving system conversion efficiency.

[0005] To achieve the above objectives, one aspect of this application proposes a multi-inductor multi-output DC-DC voltage converter. The converter includes several basic unit modules and a charge redistribution module. The basic unit modules are connected in series, and each basic unit module is connected to the charge redistribution module.

[0006] The basic unit module is used to reduce the switching withstand voltage and provide the output voltage;

[0007] The charge redistribution module is used to redistribute the capacitor charge in the basic unit module to achieve power decoupling.

[0008] In some embodiments, the basic unit module includes a first power switch, a second power switch, a third power switch, a first flying capacitor, a first DC capacitor, and a first inductor. The second terminal of the first DC capacitor is connected to the first terminal of the first power switch and is connected to a high-level voltage UP. The second terminal of the first power switch, the first terminal of the second power switch, and the first terminal of the first flying capacitor are connected to a second conversion node. The second terminal of the first flying capacitor, the first terminal of the third power switch, and the first terminal of the first inductor are connected to a first conversion node. The first terminal of the first DC capacitor is grounded, the second terminal of the third power switch is grounded, the second terminal of the second power switch is connected to a low-level voltage DOWN, and the second terminal of the first inductor serves as the output terminal of the basic unit module.

[0009] In some embodiments, the first power switch, the second power switch, and the third power switch are used to switch the connection mode of the capacitor and the inductor, the first flying capacitor is used for energy transmission, the first DC capacitor is used to provide a voltage source with an intermediate level, the duty cycle of the two cascaded basic unit modules is decoupled, and the first inductor is used to filter the switching node to obtain the output voltage.

[0010] In some embodiments, the charge redistribution module includes a plurality of power switches and a second DC capacitor. The second terminal of the second DC capacitor is grounded, and the first terminal of the second DC capacitor is connected to the second terminals of the plurality of power switches and the low-level voltage of the first basic unit module. The first terminals of the plurality of power switches are respectively connected to the first conversion nodes of the plurality of basic unit modules.

[0011] To achieve the above objectives, another aspect of this application proposes a control method for a multi-inductor multi-output DC voltage converter, the method comprising the following steps:

[0012] Based on the input voltage signal and the basic unit module, the first inductor is alternately magnetized and demagnetized in a complete cycle to obtain the load end output current and load end output voltage.

[0013] The first flying capacitor current is obtained and combined with the load terminal output current and the load terminal output voltage. Based on the charge redistribution module, the inductor current is adjusted and the adjusted inductor current is output.

[0014] In some embodiments, during the magnetization phase of the first inductor, the first power switch in the basic unit module and the switch in the charge redistribution module are both in the on state, the second power switch and the third power switch in the basic unit module are in the off state, the first flying capacitor in the basic unit module is connected to the second DC capacitor in the charge redistribution module through the switch, and the first DC capacitor in the basic unit module charges the first flying capacitor and the first inductor through the first power switch.

[0015] In some embodiments, during the demagnetization phase of the first inductor, the first power switch in the basic unit module and the switch in the charge redistribution module are both in the off state, the second power switch and the third power switch in the basic unit module are in the on state, the first flying capacitor in the basic unit module is disconnected from the first DC capacitor in the basic unit module and the second DC capacitor in the charge redistribution module, the first flying capacitor is in the discharge state, and the first inductor draws charge from the ground terminal GND through the third power switch.

[0016] In some embodiments, it also includes:

[0017] During the magnetization period, the voltage of the first switching node is the high-level voltage UP minus the low-level voltage DOWN, and the voltage of the second switching node is the high-level voltage UP.

[0018] During the demagnetization phase, the voltage of the first switching node is 0, and the voltage of the second switching node is a low-level voltage (DOWN).

[0019] In some embodiments, the charge redistribution module adjusts the inductor current so that the currents output by different output channels are independent of each other.

[0020] In some embodiments, it also includes:

[0021] The converter is periodically controlled, and when the converter enters a steady-state operating state, the steady-state voltage on the first DC capacitor in the first basic unit module of the converter is V. DC1 =2×V IN / (N+1), the steady-state voltage on the first DC capacitor in the second basic unit module is V. DC2 =3×V IN / (N+1), the steady-state voltage on the first DC capacitor in the (N-1)th basic unit module is V. DC(N-1) =N×V IN / (N+1), the steady-state voltage of the first DC capacitor in the Nth basic unit module is V D □□=(N+1)×VIN / (N+1);

[0022] The voltage stress of the first flying capacitor in the first basic unit module is V. CF1 =1×V IN / (N+1), the voltage stress of the first flying capacitor in the second basic unit module is V CF2 =2×V IN / (N+1), the voltage stress of the first flying capacitor in the (N-1)th basic unit module is V CF(N-1) = (N-1)×V IN / (N+1), the voltage stress of the first flying capacitor in the Nth basic unit module is V CFN =N×V IN / (N+1), the steady-state voltage of the second DC capacitor in the charge redistribution module is V R =V IN / (N+1);

[0023] Where N represents the number of basic units of the converter, i.e., the number of output channels, and V IN This indicates the input voltage.

[0024] The embodiments of this application include at least the following beneficial effects: This application provides a scalable multi-inductor multi-output DC-DC voltage converter and its control method. This scheme can reduce the voltage stress on the switches and inductors by lowering the switching withstand voltage and providing the output voltage through the basic unit module, thereby enhancing the ability to support higher input voltages and more output channels. The charge redistribution module redistributes the capacitor charge in the basic unit module, realizing power decoupling. This reduces the need for external components, increases the system power density, achieves high power transmission efficiency, and ensures the independence of each output. This topology can be flexibly constructed by selecting an appropriate number of basic units N according to conditions such as input voltage requirements, number of output channels, conversion ratio, switching withstand voltage, capacitor withstand voltage, and passive device size, thereby adapting to different application requirements. This flexible design makes the converter widely applicable in various application scenarios. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of a multi-inductor multi-output DC voltage converter provided in an embodiment of this application;

[0026] Figure 2 This is a flowchart illustrating the steps of a control method for a multi-inductor multi-output DC voltage converter provided in an embodiment of this application.

[0027] Figure 3 This is a schematic diagram of the basic unit of the hybrid topology provided in the embodiments of this application;

[0028] Figure 4 This is a schematic diagram of the working state of the basic unit of the hybrid topology provided in the embodiments of this application;

[0029] Figure 5 This is a schematic diagram of the structure of the N+1:1 scalable N-output hybrid topology buck converter provided in the embodiments of this application;

[0030] Figure 6 This is a schematic diagram of the 3:1 dual-output hybrid topology buck converter provided in the embodiments of this application;

[0031] Figure 7 This is a schematic diagram of the working process of the 3:1 dual-output hybrid topology buck converter provided in the embodiments of this application;

[0032] Figure 8 This is a schematic diagram of the key node voltage waveform of the 3:1 dual-output hybrid topology buck converter provided in the embodiments of this application;

[0033] Figure 9 This is a schematic diagram of the current distribution ratio of the 3:1 dual-output hybrid topology buck converter provided in the embodiments of this application;

[0034] Figure 10 This is a schematic diagram illustrating the current distribution working principle of the 3:1 dual-output hybrid topology buck converter provided in this application embodiment;

[0035] Figure 11 This is a schematic diagram of the steady-state key waveform test of the 3:1 dual-output buck converter provided in the embodiments of this application;

[0036] Figure 12 This is a schematic diagram of the steady-state key waveform test of the 5:1 four-output buck converter provided in the embodiments of this application;

[0037] Figure 13 This is a visual diagram illustrating the efficiency results of the dual-output buck converter provided in this application embodiment;

[0038] Figure 14 This is a visual diagram illustrating the efficiency results of the four-output buck converter provided in this application embodiment. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of systems and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.

[0040] It is understood that the terms “first,” “second,” etc., used in this application may be used herein to describe various concepts, but unless otherwise stated, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of the embodiments of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the words “if,” “when,” or “in response to a determination” as used herein may be interpreted as “when…” or “when…” or “in response to a determination.”

[0041] As used in this application, the terms "at least one", "multiple", "each", "any", etc., "at least one" includes one, two or more, "multiple" includes two or more, "each" refers to each of the corresponding multiples, and "any" refers to any one of the multiples.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0043] First, it's important to note that with the rapid development of data centers and cloud computing driven by emerging technologies such as artificial intelligence, the number of servers has surged, leading to a continuous increase in overall power consumption. Simultaneously, multiple low-voltage power rails at the load end are crucial for high energy efficiency and refined power management. As the core of the power management unit, the DC-DC converter typically requires a higher input voltage to transmit greater power and reduce transmission losses. Therefore, the market urgently needs converters with high input voltage (V... IN High voltage conversion ratio (VCR, defined as V) IN / V OUT A high-efficiency, high-density buck converter with multiple output channels.

[0044] In view of this, this application provides a multi-inductor multi-output DC-DC voltage converter, which can be flexibly constructed according to input voltage requirements, number of output channels, conversion ratio, switch withstand voltage, capacitor withstand voltage, and passive component size, thereby adapting to different application needs and maintaining high efficiency and stable performance under different load conditions.

[0045] Reference Figure 1 , Figure 1 This is a structural diagram of a multi-inductor multi-output DC voltage converter provided in an embodiment of the present invention, with reference to... Figure 1 The converter includes several basic unit modules and a charge redistribution module. The basic unit modules are connected in series, and each basic unit module is connected to the charge redistribution module.

[0046] The basic unit module is used to reduce the switching withstand voltage and provide the output voltage;

[0047] Specifically, the basic unit module includes a first power switch M Ai Second power switch M Bi Third power switch M Ci First flying capacitor C Fi First DC capacitor C DCi and the first inductor L i The second terminal of the first DC capacitor is connected to the first terminal of the first power switch and connected to a high-level voltage UP. The second terminal of the first power switch, the first terminal of the second power switch, and the first terminal of the first flying capacitor are connected to the second switching node V. Yi The second terminal of the first flying capacitor, the first terminal of the third power switch, and the first terminal of the first inductor are connected to the first switching node V. Xi The first terminal of the first DC capacitor is grounded, the second terminal of the third power switch is grounded, the second terminal of the second power switch is connected to a low-level voltage DOWN, and the second terminal of the first inductor serves as the output terminal of the basic unit module. The first, second, and third power switches are used to switch the connection mode of the capacitor and inductor. The first flying capacitor is used for energy transfer, the first DC capacitor is used to provide an intermediate-level voltage source, decouple the duty cycle of the two cascaded basic unit modules, and the first inductor is used to filter the switching node to obtain the output voltage.

[0048] In this embodiment, as Figure 3 as well as Figure 4 As shown, the basic unit of this multi-output converter consists of three power switches M Ai M Bi M Ci It consists of three energy storage elements, specifically including: a power switch for switching the capacitor-inductor connection mode to realize power transmission; a flying capacitor C FiIt participates in energy transfer; a DC capacitor C DCi This can be viewed as a voltage source providing an intermediate level, used to decouple the duty cycles of the two cascaded stages; and an inductor L. i The switching node is filtered to obtain the output voltage. In the inductor L... i During the magnetization period, M Ai On, L i and C Fi Charging from the upstream basic unit. During the inductor demagnetization period, C Fi Through switch M Bi and M Ci The charge stored during the magnetization period is transferred to the downstream basic unit. Transition node V Yi The voltage switches between the UP and DOWN node levels; the UP node level is used during magnetization, and the DOWN node level is used during demagnetization. Switching node V Xi The voltage swing is equal to UP–DOWN, the level is UP–DOWN during the magnetization period, and the level is 0 during the demagnetization period. This operating mode will make the power of each output related, because the charge extracted by output i will be transferred equally to output i+1.

[0049] The charge redistribution module is used to redistribute the capacitor charge in the basic unit module to achieve power decoupling.

[0050] Specifically, the charge redistribution module includes several switching transistors M Ri With the second DC capacitor C CP The second terminal of the second DC capacitor is grounded, and the first terminal of the second DC capacitor is connected to the second terminal of several switching transistors and the low-level voltage of the first basic unit module. The first terminals of several switching transistors are respectively connected to the first switching nodes of several basic unit modules.

[0051] In this embodiment, the introduced charge redistribution module uses a DC capacitor (C CP As a charge pool, it is controlled by switch M Ri Reassignment in V R The remaining charge on the surface is distributed to the output of each channel, effectively solving this problem. Therefore, at the output end, each basic unit can be connected in parallel to provide multiple independent outputs. Specifically, during the magnetization period, through M... Ri An auxiliary path was added to decouple the output current (I0). oi ) and flying capacitor C Fi Current in (I) CFi If the load on output i is much greater than that on other channels, M Ri Charge redistribution can be performed on output channel i (I Ri Therefore, C FiLess charge is transferred to the lighter downstream cells, and less charge is needed from the upstream cells, thus achieving charge balance across all flying capacitors. Otherwise, when cell i has a lighter load, the charge redistribution current (Ii) is higher. Ri () can also be negative.

[0052] In summary, the embodiments of the present invention consist of several basic units and a charge redistribution module. Each basic unit is responsible for reducing the switching withstand voltage and providing an output, while the charge redistribution module is responsible for redistributing the capacitor charge within the basic units, thereby achieving power decoupling. Figure 1 As shown, each basic unit is connected in series to reduce voltage stress on the switches and inductors, enhancing the ability to support higher input voltages and more output channels. Simultaneously, this structure shares the flying capacitor in each basic unit. To address the issue of non-independent output power across channels due to the shared flying capacitor, a charge redistribution module is introduced. Therefore, this connection method reduces external components, increases system power density, while ensuring the independence of each output. In two-phase operation, when there are N output channels, the voltage stress faced by all power switches is V. IN / (N+1), therefore, low-voltage devices with low parasitic effects can be used to improve system conversion efficiency. Therefore, the duty cycle D of each channel... i Only by input voltage (V) IN ) and the output voltage (V) of this channel oi The expression is D. i =V oi / [(N+1)×V IN ] Transformation node V SW The voltage stress is reduced to 1 / (N+1) times that of a traditional inductive buck converter, so we call it an (N+1):1 N-output buck converter.

[0053] It should also be noted that, for example Figure 5 As shown, the upstream end (UP) of each basic unit is connected sequentially to the downstream end (DOWN), and the downstream end of the last basic unit is connected to port C0 of the charge redistribution module. CP Then, port V1 of basic unit 1... X1 Connected to port 1 of the charge redistribution module, and port 2 of basic unit 2 V X2 Connect to port 2 of the charge redistribution module, and so on to port N of the basic unit N. XN Connect to the N port of the charge redistribution module. A switched-capacitor N-output DC-DC converter with a voltage conversion ratio of (N+1):1 can be implemented using N basic units.

[0054] For the connection of basic units, the upstream end (UP) of each basic unit is connected to the downstream end (DOWN) of the next basic unit in sequence.

[0055] For the charge redistribution module connection, connect the downstream end (DOWN) of the last basic unit to the 0 port (C) of the charge redistribution module. CP ). Port V of each basic unit X1 V X2 ,…,V XN Connect to the corresponding ports 1, 2, ..., N of the charge redistribution module respectively.

[0056] Please see Figure 2 This application also provides a control method for a multi-inductor multi-output DC voltage converter, which can realize the above-mentioned multi-inductor multi-output DC voltage converter. The method includes the following steps:

[0057] S100. Based on the input voltage signal and the basic unit module, the first inductor is alternately magnetized and demagnetized in a complete cycle to obtain the load end output current and load end output voltage.

[0058] In some specific embodiments, during the magnetization stage of the first inductor, the first power switch in the basic unit module and the switch in the charge redistribution module are both in the on state, the second power switch and the third power switch in the basic unit module are in the off state, the first flying capacitor in the basic unit module is connected to the second DC capacitor in the charge redistribution module through the switch, and the first DC capacitor in the basic unit module charges the first flying capacitor and the first inductor through the first power switch.

[0059] During the magnetization period, the voltage swing of the first conversion node is the voltage difference between the high-level voltage UP and the low-level voltage DOWN, and the voltage of the second conversion node is the high-level voltage UP.

[0060] In some specific embodiments, during the demagnetization stage of the first inductor, the first power switch in the basic unit module and the switch in the charge redistribution module are both in the off state, the second power switch and the third power switch in the basic unit module are in the on state, the first flying capacitor in the basic unit module is disconnected from the first DC capacitor in the basic unit module and the second DC capacitor in the charge redistribution module, the first flying capacitor is in the discharge state, and the first inductor draws charge from the ground terminal GND through the third power switch.

[0061] During the demagnetization phase, the voltage of the first switching node is 0, and the voltage of the second switching node is a low-level voltage (DOWN).

[0062] S200: Obtain the first flying capacitor current and combine it with the load terminal output current and load terminal output voltage. Based on the charge redistribution module, adjust the inductor current and output the adjusted inductor current.

[0063] In some specific embodiments, the inductor current is regulated based on the charge redistribution module and then output to the load terminal, so that the load current provided by different output channels is completely independent, that is, the load current of different output channels can be the same or different.

[0064] When the converter is periodically controlled and enters a steady-state operating state, the steady-state voltage across the first DC capacitor in the first basic unit module of the converter is V. DC1 =2×V IN / (N+1), the steady-state voltage on the first DC capacitor in the second basic unit module is V. DC2 =3×V IN / (N+1), the steady-state voltage on the first DC capacitor in the (N-1)th basic unit module is V. DC(N-1) =N×V IN / (N+1), the steady-state voltage of the first DC capacitor in the Nth basic unit module is V DCN = (N+1)×V IN / (N+1);

[0065] The voltage stress of the first flying capacitor in the first basic unit module is V. CF1 =1×V IN / (N+1), the voltage stress of the first flying capacitor in the second basic unit module is V CF2 =2×V IN / (N+1), the voltage stress of the first flying capacitor in the (N-1)th basic unit module is V CF(N-1) = (N-1)×V IN / (N+1), the voltage stress of the first flying capacitor in the Nth basic unit module is V CFN =N×V IN / (N+1), the steady-state voltage of the second DC capacitor in the charge redistribution module is V R =V IN / (N+1);

[0066] Where N represents the number of basic units of the converter, i.e., the number of output channels, and V IN This indicates the input voltage.

[0067] Furthermore, taking a dual-output converter as an example, such as Figure 6The diagram illustrates the topology of the proposed 3:1 dual-output hybrid topology buck converter. This converter consists of two basic units and a charge redistribution module. The voltage and current regulation of the two output channels are independent, thus providing two non-interfering outputs. Each channel comprises two operating periods: an inductor magnetization period and an inductor demagnetization period. Figure 7 as well as Figure 8 This diagram illustrates the voltage conversion process and waveforms at key nodes. Here, 'i' represents the element corresponding to the basic unit 'i'.

[0068] During the first magnetization period, switch M Ai and M Ri On, switch M Bi and M Ci Turn off, flying capacitor C Fi Charging, via M Ri With DC capacitor C CP Connection; DC capacitor C DCi Through M Ai and C Fi Towards inductor L i Charging. During the second demagnetization phase, switch M... Bi and M Ci On, switch M Ai and M Ri Turn off, flying capacitor C Fi Discharge, disconnect from DC capacitor C DCi C CP Connection, inductor L i Through M Ci Charge is drawn from the ground terminal GND.

[0069] In this topology, the presence of DC capacitors reduces the voltage stress on the power switches. By analyzing the operating state of the channels and applying Kirchhoff's laws, the voltage stress on each switch can be calculated to be V. IN / 3, the same voltage stress also allows the topology to be extended. Based on this voltage stress, the input voltage V IN When the voltage is 12V, 5V devices can be used, significantly improving system efficiency. Under steady state, the voltage distribution of each capacitor is as follows: DC capacitor C DC2 C DC1 and charge redistribution module C CP The steady-state voltages are respectively V DC2 =V IN V D1C =2×V IN / 3 and V R =V IN / 3; Flying capacitor C F2 and C F1 The voltage stresses are respectively 2×VIN / 3、V IN / 3. Furthermore, the conversion node V X1 and V X2 In 0 and V R When switching between them, the conduction time = duty cycle (D i )* Period (T) swi The operating state of each channel i is determined by its own. Through reasonable voltage distribution and control, this topology can operate stably under different load conditions.

[0070] like Figure 9 As shown, the proposed 3:1 dual-output buck converter demonstrates the current (I) provided by the redistribution module under different load conditions. Ri ) and the flying capacitor provides current (I CFi The ratio change between the two output channels. The discussion is categorized according to different load conditions. First, there is the case where the two output channels are under balanced load, i.e., when the load currents of the first and second output channels are equal. Second, there is the case where the two output channels are under unbalanced load, where the load current of the second output channel is greater than that of the first output channel (or vice versa).

[0071] For balanced load case I O2 =I O1 At that time, it exists that:

[0072] I O2 =I R2 +I CF2 ,I R2 =0.5×I CF2

[0073] I O1 =I R1 +I CF1 ,I R1 =0.5×I CF1

[0074] The load current of the first and second channels is provided by the current from the flying capacitor and the redistribution module.

[0075] For unbalanced load conditions when I O2 =2I O1 At that time, it exists that:

[0076] I O2 =I R2 +I CF2 ,I R2 =I CF2

[0077] I O1 =I CF1 ,I R1 =0

[0078] That is, the first channel only passes through the flying capacitor C. F1 The current is supplied to the second channel by the flying capacitor C. F2 It is supplied together with the current of the redistribution module.

[0079] For unbalanced load conditions when I O2 >2I O1 At that time, it exists that:

[0080] I O2 =I R2 +I CF2 +I R1 ,I R2 >I CF2

[0081] I O1 =I CF1 ,I R1 <0

[0082] That is, the excess current in basic unit 1 flows in reverse into basic unit 2, providing more charge to meet the larger load demand, indicating that basic unit 2 reuses the components of basic unit 1 and improves the component utilization rate.

[0083] Taking one scenario as an example to analyze the operating state, when the load current I of the second channel... O2 It is the first channel load current I O1 When it is twice the size, such as Figure 10 As shown, when basic unit 1 is operating during the magnetization period, switch M A1 and M R1 On, switch M B1 and M C1 Turn off, DC capacitor C DC1 Through M A1 and C F1 Charging inductor L1, flying capacitor C F1 The load current I through the first channel is only through the inductor L1. O1 Charging is performed, that is, the flying capacitor provides current I. CF1 >I O1 Because I O1 The C is relatively small, in order to avoid excessive charge transfer to the basic unit 1. F1 Will be through M R1 Transfer excess charge to C CP Or basic unit 2. When basic unit 2 is operating during the magnetization period, switch M... A2 and M R2 On, switch M B2 and M C2 Turn off, DC capacitor C DC2 Through M A2 and C F2Charging inductor L2, the load current of the second output channel is related to the flying capacitor C. F2 Provide the current relationship as I O2 >I CF2 Meanwhile, the DC capacitor C CP Or basic unit 1 through M R2 Provide more charge to output channel 2 to meet the larger load current I of the second channel. O2 With the help of the charge redistribution module (C CP +M Ri Each output current is independent and unaffected by other channels. Even if an output is unloaded, its capacitor network can be reused by a fully loaded path, thus significantly improving component utilization.

[0084] From a voltage perspective, both output channels can operate simultaneously during the magnetization period, or simultaneously during the demagnetization period, or one channel can operate during the magnetization period while the other operates during the demagnetization period. The duty cycle parameters of each output channel are independent, and multi-voltage outputs can be achieved through differentiated adjustment to meet the voltage requirements of different loads. The C in each unit... DCi The presence of [specific feature] allows for overlapping duty cycles, enabling all inductor currents to rise simultaneously. Independent transient responses for each channel ensure fast transient response across all channels. This achieves flexible operating modes and efficient dynamic response.

[0085] like Figure 11 As shown, a test waveform of the steady-state key waveforms of the proposed 3:1 dual-output buck converter is presented. In this test waveform, the two output channels provide different output voltages, and the node voltage variations are consistent with the theoretical analysis results. By comparing the test waveforms with the theoretical predictions, the voltage distribution and performance of this topology under steady-state conditions can be verified, indicating that the system can operate stably as expected and provide the required output voltage.

[0086] The system can be cascaded at any number of levels. For example, in addition to connecting individual basic units together, we can also cascade two dual-output buck converters according to... Figure 5 The connection method shown is used for cascading to construct a four-output buck converter. In this configuration, the conversion ratio is 5:1, and the voltage stress on the power switches is reduced to V. IN / 5, V Xi The voltage swing at the node is V INA 5:1 quad-output buck converter was constructed using the cascaded configuration. This means the system can support higher input voltages, further reducing transmission line losses and improving overall efficiency. When the input voltage is increased to 24V, this cascading method allows the power switch to continue using low-voltage components while supporting higher input voltages and providing four independent output channels. To further verify the scalability of this topology, two 3:1 dual-output buck converter chips were connected on the PCB to construct a 5:1 quad-output buck converter. The steady-state waveform test results are as follows: Figure 12 As shown, each of the four output channels provides a different voltage. When the input voltage is 24V, the voltage or voltage swing at each node is consistent with the theoretical value, which is V. IN / 5 = 4.8V, verifying the scalability and stability of this topology in practical applications.

[0087] like Figure 13 as well as Figure 14 The figure shows the efficiency test curves of the dual-output and quad-output buck converters at 12V and 24V input voltages, respectively. The figure demonstrates that with a shared switched capacitor design (including flying capacitor and DC capacitor), the peak efficiency decreases by only 1.4% when the output voltage of each output channel is 1.2V and the input voltage increases from 12V to 24V. This highlights the superior scalability of the design. Expanding to more outputs can support higher input voltages while maintaining high system efficiency. This underscores the effectiveness of the design.

[0088] It is understood that the content of the above method embodiments is applicable to this system embodiment. The specific functions implemented in this system embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0089] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A multi-inductor, multi-output DC-DC voltage converter, characterized in that, The converter includes several basic unit modules and a charge redistribution module. The basic unit modules are connected in series, and each basic unit module is connected to the charge redistribution module. The basic unit module is used to reduce the switching withstand voltage and provide the output voltage; The charge redistribution module is used to redistribute the capacitor charge in the basic unit module to achieve power decoupling; The basic unit module includes a first power switch, a second power switch, a third power switch, a first flying capacitor, a first DC capacitor, and a first inductor. The second terminal of the first DC capacitor is connected to the first terminal of the first power switch and connected to a high-level voltage UP. The second terminal of the first power switch, the first terminal of the second power switch, and the first terminal of the first flying capacitor are connected to a second conversion node. The second terminal of the first flying capacitor, the first terminal of the third power switch, and the first terminal of the first inductor are connected to a first conversion node. The first terminal of the first DC capacitor is grounded, the second terminal of the third power switch is grounded, the second terminal of the second power switch is connected to a low-level voltage DOWN, and the second terminal of the first inductor serves as the output terminal of the basic unit module. The charge redistribution module includes several power switches and a second DC capacitor. The second terminal of the second DC capacitor is grounded, and the first terminal of the second DC capacitor is connected to the second terminal of the several power switches and the low-level voltage DOWN of the first basic unit module. The first terminals of the several power switches are respectively connected to the first conversion nodes of the several basic unit modules.

2. The converter according to claim 1, characterized in that, The first power switch, the second power switch, and the third power switch are used to switch the connection mode of the capacitor and the inductor. The first flying capacitor is used for energy transmission. The first DC capacitor is used to provide a voltage source with an intermediate level. The duty cycle of the two cascaded basic unit modules is decoupled. The first inductor is used to filter the switching node to obtain the output voltage.

3. A control method for a multi-inductor multi-output DC voltage converter based on claim 1, characterized in that, The method includes the following steps: Based on the input voltage signal and the basic unit module, the first inductor is alternately magnetized and demagnetized in a complete cycle to obtain the load end output current and load end output voltage. The first flying capacitor current is obtained and combined with the load terminal output current and the load terminal output voltage. Based on the charge redistribution module, the inductor current is adjusted and the adjusted inductor current is output.

4. The method according to claim 3, characterized in that, During the magnetization phase of the first inductor, the first power switch in the basic unit module and the switch in the charge redistribution module are both in the on state, the second power switch and the third power switch in the basic unit module are in the off state, the first flying capacitor in the basic unit module is connected to the second DC capacitor in the charge redistribution module through the switch, and the first DC capacitor in the basic unit module charges the first flying capacitor and the first inductor through the first power switch.

5. The method according to claim 3, characterized in that, During the demagnetization phase of the first inductor, the first power switch in the basic unit module and the switch in the charge redistribution module are both in the off state, the second power switch and the third power switch in the basic unit module are in the on state, the first flying capacitor in the basic unit module is disconnected from the first DC capacitor in the basic unit module and the second DC capacitor in the charge redistribution module, the first flying capacitor is in the discharge state, and the first inductor draws charge from the ground terminal GND through the third power switch.

6. The method according to claim 3, characterized in that, Also includes: During the magnetization period, the voltage of the first switching node is the high-level voltage UP minus the low-level voltage DOWN, and the voltage of the second switching node is the high-level voltage UP. During the demagnetization phase, the voltage of the first switching node is 0, and the voltage of the second switching node is a low-level voltage (DOWN).

7. The method according to claim 3, characterized in that, The charge redistribution module adjusts the inductor current to make the currents output by different output channels independent of each other.

8. The method according to claim 3, characterized in that, Also includes: The converter is periodically controlled, and when the converter enters a steady-state operating state, the steady-state voltage on the first DC capacitor in the first basic unit module of the converter is: The steady-state voltage on the first DC capacitor in the second basic unit module is , No. The steady-state voltage across the first DC capacitor in the basic unit module is , No. The steady-state voltage of the first DC capacitor in the basic unit module is ; The voltage stress of the first flying capacitor in the first basic unit module is The voltage stress of the first flying capacitor in the second basic unit module is , No. The voltage stress of the first flying capacitor in the basic unit module is , No. The voltage stress of the first flying capacitor in the basic unit module is The steady-state voltage of the second DC capacitor in the charge redistribution module is ; in, This indicates the number of basic units the converter has, i.e., the number of output channels. This indicates the input voltage.

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