Multi-phase dynamic scheduling adaptive conduction time control Buck converter

Abstract

The invention discloses a multiphase dynamic scheduling adaptive conduction time control Buck converter based on phase interpolation. The converter comprises a self-adaptive turn-on time control module, a phase interpolation control module and a dynamic phase scheduling module, the number of working phases can be dynamically adjusted according to load current changes, a multi-phase clock signal is generated through a phase interpolation method, and high-precision multi-phase current-sharing control is achieved. According to the invention, the output ripple of the system is reduced, the bandwidth and dynamic response performance of the system are improved, the energy efficiency under a light-load working condition is remarkably improved, and the method is suitable for a high-performance chip power supply system.

Description

Technical Field

[0001] The present invention relates to the technical field of switching power supplies, and specifically to a multi-phase synchronous buck switching power supply control method, and more particularly to a multi-phase dynamic scheduling adaptive on-time control Buck converter based on phase interpolation, which is suitable for power management modules in chip power supply systems such as high-performance processors, artificial intelligence chips, and communication systems. Background Art

[0002] Multi-phase Buck converters are widely used in power supply systems such as modern high-performance processors, artificial intelligence (AI) chips, and communication base station chips due to their good current sharing capability, small output voltage ripple, and high load response speed.

[0003] However, existing multi-phase buck control solutions, such as TI's D-CAP+ technology and Renesas' ISL68227 multi-phase controller, while improving load response speed and phase synchronization accuracy, still suffer from complex control logic, high light-load power consumption, and insufficient dynamic current sharing accuracy. Especially under high-frequency, high-current load shedding conditions, current imbalance can easily lead to uneven power distribution between phases, affecting system stability and making it difficult to meet the high reliability and efficiency requirements of power systems for AI chips, 5G base stations, and other applications.

[0004] Existing phase control technologies mainly include a Pulse Distributor (PD) control method and a Phase Locked Loop (PLL) control method.

[0005] The PD control method has a simple structure, but in multi-phase interleaved control, due to the phase error and the noise generated by the ripple cancellation point, the system is prone to jitter and response lag, which limits the bandwidth and stability of the system.

[0006] The PLL control method can achieve precise phase control, but its control circuit is complex, power-hungry, and requires a large chip area, making it difficult to apply in light-load, high-efficiency scenarios. Furthermore, multi-phase systems require multiple PLL modules, further increasing the complexity of the control circuit and the design difficulty.

[0007] At the same time, most existing multi-phase Buck converters adopt a fixed-phase working mode and cannot flexibly adjust the number of phases involved in the work according to load changes, resulting in low system efficiency under light load conditions.

[0008] Therefore, the existing technology still has problems such as complex control system, low light-load efficiency and insufficient dynamic response capability. There is an urgent need for a multi-phase Buck converter control method with simple control structure, high light-load efficiency and excellent dynamic performance. Summary of the Invention

[0009] The present invention aims to solve the problems of complex control systems, low light-load efficiency, and insufficient dynamic response of existing multi-phase Buck converters, and provides a multi-phase dynamic scheduling adaptive on-time control Buck converter based on phase interpolation.

[0010] The Buck converter provided by the present invention adopts a phase interpolator (PI) control method, combined with an adaptive on-time (AOT) control strategy, and introduces a dynamic phase scheduling module to dynamically adjust the number of working phases according to changes in load current, thereby optimizing system energy efficiency and load transient response performance.

[0011] Compared with the prior art, the present invention has the following advantages:

[0012] High-precision multi-phase phase misalignment is achieved through PI technology to reduce system output ripple and phase jitter.

[0013] The AOT control strategy is used to improve the control system bandwidth and optimize the load response performance.

[0014] A dynamic phase scheduling strategy is adopted to automatically adjust the number of working phases according to the load current to achieve a light-load single-phase, high-efficiency and low-power working mode.

[0015] The control circuit has a simple structure and low power consumption, and is suitable for integration into a power management module (PMIC) of a high-performance chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the prior art and the drawings required for use in the embodiments. The following drawings are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0017] Figure 1 This is a block diagram of a multi-phase dynamic scheduling adaptive on-time control Buck converter system according to an embodiment of the present invention;

[0018] Figure 2 This is a flow chart of a phase interpolation adjustment control method according to an embodiment of the present invention;

[0019] Figure 3 1 is a structural block diagram of a phase interpolation and adaptive on-time control module in an embodiment of the present invention;

[0020] Figure 4 Schematic diagram of theoretical working waveforms when the system load changes suddenly in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The following, combined with the accompanying drawings and examples, further describes in detail a multiphase dynamic scheduling and adaptive on-time control Buck converter based on phase interpolation. The present invention is not limited to the specific structures or parameters described in the following examples, and those skilled in the art may make appropriate adjustments or optimizations based on actual needs.

[0022] The present invention provides a multi-phase dynamic scheduling adaptive on-time control Buck converter based on phase interpolation, please refer to the attached Figure 1 , Figure 1 This is a schematic diagram of the overall structure of the converter of the present invention, which includes the following key parts:

[0023] The system first includes an input power supply terminal V in , used to provide a stable input voltage for the entire multi-phase Buck converter. Output terminal V out Provide power to the load and ensure that the load voltage meets the system design requirements.

[0024] In the power module part, a multi-phase parallel structure design is adopted. Each phase contains a MOSFET power switch module, as well as an output filter inductor and filter capacitor to reduce the output voltage ripple and improve the system conversion efficiency.

[0025] The control system features an Adaptive On-Time Control (AOT) module, which dynamically adjusts the on-time of each phase based on load conditions, improving the system's dynamic response and voltage regulation. A Phase Interpolator (PI) module also generates multi-phase staggered clock signals based on system clock signals and load information, enabling uniform scheduling and seamless switching between phases and reducing current surges during phase switching.

[0026] In addition, the dynamic phase scheduling module dynamically adjusts the number of working phases of the multi-phase power module by monitoring load demand in real time to achieve the best balance between efficiency and output performance under different load conditions.

[0027] The system also includes a load detection module and a current detection module, which are used to detect the output voltage status and load current changes respectively, and provide real-time feedback signals to the control module to ensure that the system dynamically adjusts phase scheduling and conduction time control according to preset strategies.

[0028] Through the coordinated control of the above modules, the multi-phase Buck converter of the present invention can achieve fast, efficient and stable dynamic load response, and is particularly suitable for chip power supply application scenarios with high requirements on power supply dynamic performance and efficiency.

[0029] This invention is suitable for power supply systems used in advanced SoC chips, such as modern high-performance processors, graphics processors, artificial intelligence chips, and network communication chips. During operation, these chips experience dramatic load fluctuations and significant transient increases in power consumption, placing extremely high demands on the power supply system's dynamic response, output stability, and energy efficiency. Traditional multi-phase power supply solutions with fixed phases or complex PLL control suffer from high power consumption, slow transient response, and complex control, making them difficult to meet the power supply needs of high-performance chips.

[0030] The present invention meets the requirements of high bandwidth, fast response and low power consumption of chip power supply by combining PI, dynamic scheduling and adaptive on-time control, and has good application prospects.

[0031] In the multi-phase dynamic scheduling adaptive on-time control Buck converter of the present invention, AOT is responsible for out With reference voltage V ref The module dynamically generates an on-time adjustment signal based on the error signal between the two. This module can adjust the switching period in real time, achieving a rapid response to load changes and further improving the system's dynamic regulation performance.

[0032] Specifically, the AOT control module uses a capacitor charging control method. Based on the error signal detected by the system, it controls the capacitor charging time, generating control pulses of varying widths to achieve adaptive adjustment of the on-time. When the load current increases, the AOT control module automatically shortens the on-time, increasing the switching frequency and system response speed. Conversely, when the load current decreases, the on-time is extended to reduce the system switching frequency, effectively improving the system's light-load energy efficiency.

[0033] Please refer to Figure 2 , Figure 2 The transformation described in the present invention is characterized by a flow chart of the phase interpolation adjustment control method. The phase interpolation control module (Phase Interpolator, PI control module for short) is used to receive the system master clock signal, perform multi-phase clock interpolation processing, and generate a multi-phase clock signal with equal phase difference. The module uses a digital circuit to implement phase interpolation, and the interpolation accuracy is better than 5°, which ensures the accuracy of multi-phase current sharing control and improves the multi-phase interleaving bandwidth of the system. The multi-phase clock signal output by the phase interpolation control module is used to drive each phase power switching device respectively to achieve precise synchronization and phase-shift control between each phase. Compared with the traditional phase detection (PD) control method, the present invention adopts phase interpolation technology to effectively avoid the system jitter problem caused by the output ripple offset point. In addition, the PI control module adopts a digital circuit architecture, which further reduces the power consumption and hardware implementation complexity of the control system, and improves the integration and reliability of the overall system.

[0034] The principle of the dynamic phase scheduling module is as follows:

[0035] The dynamic phase scheduling module provided in the present invention uses a current detection module to detect the output load current in real time and compares the detected value with a preset threshold to determine the current load state of the system. When the load current is detected to be lower than a light load threshold (for example, 100mA), the control system determines that it has entered a light load condition. At this time, the dynamic phase scheduling module automatically switches to single-phase operation mode, keeping only one phase power module active and the remaining phases in a dormant state, thereby reducing system switching losses and improving energy efficiency under light load conditions.

[0036] When the load current exceeds the high-load threshold (e.g., 500mA), the dynamic phase scheduling module activates the multiphase power modules, automatically switching the system to multiphase parallel current-sharing mode to meet the current demands of high-load conditions. Simultaneously, the phase interpolation control module activates, generating clock signals with equal phase differences to ensure precise phase misalignment between phases, thereby improving the current-sharing capability and dynamic response performance of the multiphase parallel system.

[0037] In addition, refer to Figure 3 , Figure 3 This is a block diagram of the phase interpolation and adaptive on-time control module. This module dynamically adjusts the switching period based on real-time load conditions to optimize on-time control, further improving the system's dynamic load response. During operation, the system continuously monitors the current balance between phases and dynamically adjusts the on-time of each phase's power module to ensure current sharing accuracy and system stability in multi-phase parallel mode.

[0038] System implementation parameters

[0039] Input voltage V in :1.8V, output voltage V out :0.9V, maximum load current I out : 3A, working mode: supports single-phase / multi-phase dynamic switching, single-phase switching threshold: less than 100mA, multi-phase parallel threshold: greater than 500mA, switching frequency per phase: 3MHz, PI phase interpolation accuracy: ≤5°, system response time: when the load changes from 40mA to 3A, the output voltage returns to steady state in less than 2μs, light load efficiency: in single-phase mode, DCM control, efficiency is as high as 90%, controller quiescent current: within 100μA, chip area (control part): less than 0.12mm2.

[0040] The detailed working process is as follows:

[0041] 1. When the system is powered on and initialized, the PI control module generates a multi-phase clock signal and provides a synchronization signal for the multi-phase power switches.

[0042] 2. The load detection module monitors the output current status, and the dynamic scheduling module determines the number of phases to be opened based on the detection results.

[0043] 3. Under light load conditions (such as chip standby and low power consumption modes), the system only retains single-phase operation to reduce switching losses; the multi-phase power module enters a dormant state to reduce overall static power consumption.

[0044] 4. When the chip enters high-performance mode, the load current increases rapidly, and the dynamic scheduling module quickly enables other phases to improve output capacity and current sharing accuracy to meet the chip's high current requirements.

[0045] 5. The PI control module ensures accurate phase misalignment between multiple phases, achieves staggered conduction, reduces output ripple, and improves output stability.

[0046] 6. The AOT control module adaptively adjusts the on-time to improve system bandwidth and dynamic response speed, ensuring that the output voltage remains stable under high dynamic load changes.

[0047] The application of this invention has the following advantages:

[0048] Efficient power supply; single-phase operation + DCM control under light load reduces system static power consumption, dynamic scheduling realizes intelligent switching of phases, and optimizes overall energy efficiency.

[0049] Fast dynamic response: PI interpolation + adaptive on-time control greatly improves the transient response speed of the power supply to meet the frequent load mutation requirements of the chip.

[0050] Reduce system complexity: Replace complex PLL solutions, reduce control circuit area and power consumption, simplify control logic, and are suitable for high-density integration applications.

[0051] Enhanced system reliability: Dynamic scheduling avoids unnecessary phase switching, and PI interpolation improves current sharing accuracy, ensuring multi-phase operation stability.

[0052] Adaptable to high-end chip power supply systems: Suitable for powering high-performance processors such as AI chips, 5G communication chips, CPU / GPU, and meeting the technical requirements for high power bandwidth, low latency, and fast dynamic adjustment.

Claims

1. A multi-phase dynamic scheduling adaptive on-time control Buck converter based on phase interpolation, characterized in that: include: Phase interpolation control module, dynamic scheduling module, multi-phase power module, current detection and current sharing control module, load detection module; The phase interpolation control module includes a phase interpolator (PI) control and an adaptive on-time (AOT) adjustment module, the input end of which is connected to the output end of the current detection and current sharing control module and the dynamic phase scheduling module, and the output end is connected to the multi-phase power module. It is characterized in that the PI control generates a multi-phase clock signal through a phase interpolation method to achieve phase staggered control between the multi-phase power modules, and the AOT on-time adjustment module is used to adjust the on-time of the switch tube according to the output voltage signal; The dynamic scheduling module has an input end connected to the load detection module and an output end connected to the phase interpolation control module, and is used to dynamically adjust the number of working phases according to the load current; The multiphase power module, the input terminal and V in , phase interpolation control module connection, output V out , energy conversion and load power supply are performed according to the control signals output by the phase interpolation control module and the dynamic scheduling module; The input end of the current detection and current sharing control module is connected to the load detection module, which is used to detect the output current of each phase power module and adjust the conduction time of each phase power module based on the current detection result to achieve inter-phase current sharing control; The load detection module, whose output end is connected to the current detection and current sharing control module and the dynamic phase scheduling module, provides information to the current detection and current sharing control module and the dynamic phase scheduling module by collecting system output end information in real time.

2. A multi-phase dynamic scheduling adaptive on-time control Buck converter based on phase interpolation according to claim 1, characterized in that: The dynamic scheduling module is based on the load current I load Based on the real-time detection results, adjust the phase number according to the following rules: When I load When the current is less than 100mA, it enters single-phase operation mode, retaining only one phase power module and the other phases enter sleep state to reduce switching loss and improve light-load efficiency; When I load When the current is >500mA, it enters multi-phase operation mode, activates all power phases, and realizes multi-phase parallel current sharing to improve current carrying capacity, optimize dynamic response, and reduce single-phase load thermal stress.

3. The multi-phase dynamic scheduling adaptive on-time control Buck converter based on phase interpolation according to claim 1 is characterized in that: The phase interpolation control module uses a digital interpolation method to generate a multi-phase clock signal, which is used to drive the conduction control of each phase power stage to ensure that the phase deviation between each phase is less than 5°, thereby improving the current sharing accuracy and optimizing the synchronous control of the phase misalignment to reduce the current ripple and interference effects in the interleaved mode.

4. The multi-phase dynamic scheduling adaptive on-time control Buck converter based on phase interpolation according to claim 1 is characterized in that: The adaptive on-time control module generates an on-time signal T by controlling the charging time of the charging capacitor. on , and dynamically adjust T according to the load status on To optimize system performance, including: When the load current increases, shorten T on , increase the switching frequency, speed up the dynamic response speed of the power module, and reduce the output voltage fluctuation; When the load current decreases, extend T on , reduce the switching frequency to reduce switching losses and improve light load conversion efficiency.

5. The multi-phase dynamic scheduling adaptive on-time control Buck converter based on phase interpolation according to claim 1 is characterized in that: The current sharing control module monitors the output current of each phase power module in real time and dynamically adjusts the on-time difference between phases according to the current deviation of each phase to compensate for the current unevenness caused by inductor parameter mismatch, PCB trace parasitic effects and other non-ideal factors, thereby achieving precise phase-to-phase current sharing control, thereby improving the system's load sharing capability and dynamic response performance.

6. The multi-phase dynamic scheduling adaptive on-time control Buck converter based on phase interpolation according to claim 1 is characterized in that: The dynamic scheduling module includes a temperature compensation unit, which dynamically optimizes the phase scheduling strategy by detecting the ambient temperature in real time and combining it with a preset temperature-phase mapping relationship to reduce the impact of temperature changes on converter performance and improve the stability and reliability of the system.

7. The multi-phase dynamic scheduling adaptive on-time control Buck converter based on phase interpolation according to claim 1 is characterized in that: The multi-phase power module includes gallium nitride (GaN) power devices, and the GaN power devices include high electron mobility transistors (HEMTs) used to replace traditional silicon-based MOSFETs to increase switching frequency, reduce on-resistance and switching losses, and thus improve the overall conversion efficiency of the system.

8. According to claim 1, a multi-phase dynamic scheduling adaptive on-time control Buck converter based on phase interpolation, a multi-phase dynamic scheduling control method based on phase interpolation, characterized in that: The following steps are involved: S1. Detect load current I load Size, determine the current system load status; S2. When I load Under light load conditions, some phases are turned off, leaving only single-phase operation to reduce switching losses and improve energy efficiency; S3. When I load Under heavy load conditions, the multi-phase power modules are dynamically activated and enter multi-phase parallel operation mode to increase power capability and optimize dynamic response. S4. Generate equal phase difference control signals through phase interpolation to ensure accurate staggered conduction time of each phase, improving current sharing accuracy and phase synchronization control capability; S5. Combined with the adaptive on-time (AOT) control strategy, the switching cycle is dynamically adjusted according to load changes, the on-time is optimized, and the transient response speed is improved; S6. Through the current sharing control strategy, the current distribution of multi-phase power modules is balanced in real time, the power loss caused by uneven loop current is reduced, and the dynamic performance of the system is optimized.

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