Multi-track power supply system and controller and control method of multi-phase voltage stabilizer thereof

Abstract

The invention discloses a multi-track power supply system, a controller for a multi-phase voltage stabilizer in the multi-track power supply system and a corresponding control method. The controller comprises a dynamic overcurrent unit and a switch control circuit. The dynamic overcurrent unit provides an overcurrent threshold based on a system input current indicative of a total input current of the multi-phase voltage regulator and the at least one other voltage regulator. The switching control circuit provides a plurality of switching control signals to control a plurality of switching circuits of the multi-phase voltage regulator such that an output voltage of the multi-phase voltage regulator is regulated to a preset level, and controls an output current of the plurality of switching circuits based on an overcurrent threshold. The controller coordinates over-current limitation of the plurality of voltage stabilizers based on the system input current, realizes heat balance of the multi-rail power supply system by dynamically adjusting the over-current threshold value, and controls the total power consumption to avoid overheating.

Description

Technical Field

[0001] This invention relates to an electronic circuit, and more specifically, to a voltage regulator. Background Technology

[0002] The rapid development of electronic technology, especially in high-performance computing, communications, and portable consumer devices, has driven the continuous growth in power demands for integrated circuits. To meet these higher power requirements and maintain stringent voltage regulation, modern power systems employ multi-rail regulators to provide dedicated power domains for different functional units. With the increasing overall power density of systems, thermal management has become a critical design consideration, as excessively high temperatures can lead to performance degradation, shorten device lifespan, and affect reliability.

[0003] In traditional voltage regulator architectures, load line regulation is used to prevent the regulator from handling excessive current. This technique proportionally reduces the output voltage as the output current increases, thus limiting the regulator's maximum supply capacity. While this technique is suitable for single-rail configurations, it is ineffective in multi-rail power supply systems. Each power rail accumulates package thermal load; applying load line margin uniformly to all rails leads to an overly conservative power budget. As a result, the system may operate under significant redundancy, resulting in insufficient utilization of available power and consequently reduced overall performance. Summary of the Invention

[0004] Therefore, in order to solve the above-mentioned technical problems, this invention proposes a controller and control method for a multi-rail power supply system and its multi-phase voltage regulator.

[0005] According to an embodiment of the present invention, a controller for a multiphase voltage regulator in a multi-rail power supply system is provided, comprising a dynamic overcurrent unit and a switching control circuit. The dynamic overcurrent unit is configured to provide an overcurrent threshold based on a system input current, wherein the system input current indicates the total input current of the multiphase voltage regulator and at least one other voltage regulator. The switching control circuit is configured to provide multiple switching control signals to control multiple switching circuits of the multiphase voltage regulator, such that the output voltage of the multiphase voltage regulator is regulated to a preset level, wherein the output current of the multiple switching circuits is controlled based on the overcurrent threshold.

[0006] According to an embodiment of the present invention, a control method for a multiphase voltage regulator in a multi-rail power supply system is proposed, comprising: providing an overcurrent threshold; providing a plurality of switching control signals to control a plurality of switching circuits of the multiphase voltage regulator, such that the output voltage of the multiphase voltage regulator is adjusted to a preset level, and controlling the output current of the plurality of switching circuits based on the overcurrent threshold; and dynamically adjusting the overcurrent threshold according to the system input current in response to the activation of a dynamic overcurrent limiting function. The system input current indicates the total input current of the multiphase voltage regulator and at least one other voltage regulator.

[0007] According to an embodiment of the present invention, a multi-rail power supply system is proposed, including a first regulator and a second regulator. The first regulator includes an input node, an output node configured to provide a first output voltage, a first set of multiple switching circuits, and a first controller. The second regulator, wherein the first regulator includes an input node and an output node configured to provide a second output voltage, is coupled to the input node of the first regulator. The first controller is configured to dynamically set a first overcurrent threshold based on the system input current to limit the current flowing through each of the first set of multiple switching circuits. The system input current indicates the total input current of at least the first regulator and the second regulator.

[0008] Compared to traditional technologies, the controller of this invention coordinates the overcurrent limits of multiple voltage regulators based on the system input current. By dynamically adjusting the overcurrent threshold, it achieves thermal balance of the multi-rail power supply system and controls the total power consumption to avoid overheating. Attached Figure Description

[0009] To better understand this invention, it will be described in detail with reference to the following drawings. Identical or similar elements are referred to by the same reference numerals.

[0010] Figures 1A-1B A schematic diagram of a multi-rail power supply system 100 according to an embodiment of the present invention is shown.

[0011] Figures 2A-2F An example curve of the overcurrent threshold OCL according to an embodiment of the present invention is shown.

[0012] Figure 3 A schematic diagram of a dynamic overcurrent unit 30A according to an embodiment of the present invention is shown.

[0013] Figure 4 A register mapping 400 according to an embodiment of the present invention is shown.

[0014] Figure 5 A power limiting method 500 according to an embodiment of the present invention is shown.

[0015] Figure 6 A schematic diagram of a dynamic overcurrent unit 30B according to an embodiment of the present invention is shown.

[0016] Figure 7 A register mapping 700 according to an embodiment of the present invention is shown.

[0017] Figure 8 A power limiting method 800 according to an embodiment of the present invention is shown.

[0018] Figure 9 A schematic diagram of a dynamic overcurrent unit 30C according to an embodiment of the present invention is shown.

[0019] Figure 10 A schematic diagram of a multiphase voltage regulator 1000 according to an embodiment of the present invention is shown.

[0020] Figure 11 A schematic diagram of a switch control circuit 50A according to an embodiment of the present invention is shown.

[0021] Figures 12A-12C A timing diagram of a switch control circuit 50A according to an embodiment of the present invention is shown.

[0022] Figure 13 A schematic diagram of a switch control circuit 50B according to an embodiment of the present invention is shown.

[0023] Figure 14 A timing diagram of a multiphase voltage regulator 1000 according to an embodiment of the present invention is shown.

[0024] Figure 15 A control method 1500 for a multiphase voltage regulator according to an embodiment of the present invention is shown. Detailed Implementation

[0025] Specific embodiments of the present invention will now be described in detail. It should be noted that the embodiments described herein are for illustrative purposes only and are not intended to limit the invention. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other instances, well-known circuits, materials, or methods have not been specifically described to avoid obscuring the invention.

[0026] Throughout this specification, references to “an embodiment,” “an example,” or “an example” mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. Therefore, the phrases “in an embodiment,” “in an embodiment,” “an example,” or “an example” appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the accompanying drawings provided herein are for illustrative purposes and are not necessarily drawn to scale. It should be understood that when an element is referred to as “coupled” or “connected” to another element, it can be directly coupled to the other element or there may be intermediate elements. Conversely, when an element is referred to as “directly coupled to” or “directly connected” to another element, there are no intermediate elements. The same reference numerals indicate the same elements. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0027] Figures 1A-1B A schematic diagram of a multi-rail power supply system 100 according to an embodiment of the present invention is shown. The multi-rail power supply system 100 receives an input voltage VIN at an input node 101 and delivers at least one output voltage (e.g., four output voltages Vo1 to Vo4) to corresponding output nodes (e.g., 102 to 105), each output voltage supplying power to an independent load (i.e., load 1, load 2, load 3, and load 4). In one embodiment, the loads are composed of different functional units (e.g., units of an application-specific integrated circuit), each powered by a corresponding power rail.

[0028] exist Figure 1A In this example, the system input current IIN (representing the total input current of the multiple regulators in the multi-rail power supply system) flows from node 101 into the multi-rail power supply system 100. This parameter is a key monitoring indicator in subsequent control operations. The multiple regulators provide output voltages Vo1 to Vo4 respectively. Each regulator consists of a power stage (i.e.,...) Figure 1A The circuits shown are 108, 109, 110, and 111) and the control circuit (i.e. Figure 1A It consists of 112, 113, 114, and 115 shown. Figure 1ATaking the generation of output voltages Vo1 to Vo4 via four output rails (e.g., power stages 108, 109, 110, and 111) as an example, this multi-rail power supply system 100 can be flexibly expanded to any number of power rails by adding or removing power stages. In one embodiment, each power stage may include one or more switching circuits connected in parallel to provide the corresponding output voltage, with each switching circuit representing a phase. For example, each power stage 108 to 110 may contain multiple switching circuits, which, together with the corresponding control circuits 112 to 114, constitute a multiphase voltage regulator, while power stage 111 may contain only one switching circuit.

[0029] like Figure 1A As shown, the DC-DC converter 107, acting as an intermediate converter, receives the input voltage VIN and converts it into the DC bus voltage VDC. Power stages 108-111 are driven by the DC bus voltage VDC, generating output voltages Vo1-Vo4 respectively. In some configurations, the DC / DC converter 107 can be omitted, and power stages 108-111 are directly connected to the input node 101.

[0030] Each controller (i.e.) Figure 1A The power levels (i.e., 112, 113, 114, 115) shown in Figures 112, 113, 114, and 115 are monitored. Figure 1A The output voltages of (108, 109, 110, 111) shown are used to generate the corresponding switch control signal array (i.e., Figure 1A The diagram shows PWM1, PWM2, PWM3, and PWM4. The switching control signal array PWM1 includes multiple switching control signals such as PWM1_1 and PWM1_2. The switching control signal array PWM2 includes multiple switching control signals such as PWM2_1 and PWM2_2. The switching control signal array PWM3 includes multiple switching control signals such as PWM3_1 and PWM3_2. Some controllers can monitor the system input current IIN to control the output current of the corresponding power stage, thereby limiting the heat dissipation of the entire system. For example, controller 112 controls current Io1, controller 113 controls current Io2, and controller 114 controls current Io3, all based on the system input current IIN.

[0031] In one embodiment, controllers 112-114 use the system input current IIN as a real-time indicator to adjust the overcurrent threshold OCL, thereby limiting the current supplied to each phase by each switching circuit. In this way, the multi-rail power supply system 100 can more effectively constrain total power consumption according to dynamic load conditions, thus improving performance while preventing overheating. In one embodiment, the overcurrent threshold OCL decreases as the system input current IIN increases. This means that under normal load conditions, the overcurrent threshold OCL does not limit the output power provided by its corresponding power stage. Only when the system input current IIN increases (e.g., due to increased system-level power consumption) will the overcurrent threshold OCL decrease to limit the output power of its corresponding power stage.

[0032] like Figure 1A As shown, the current detection circuit 106 is used to detect the system input current IIN and output a current detection signal Iinsen. Controllers 112 to 114 receive the current detection signal Iinsen and dynamically adjust their respective overcurrent thresholds OCL according to the current detection signal Iinsen.

[0033] In one embodiment, controllers 112-114 are each equipped with a dynamic overcurrent unit 30, which can independently adjust its own overcurrent threshold OCL based on the input current detection signal Iinsen. This allows power stages 108-110 to adaptively limit their output current according to changes in the system input current IIN. Controller 115 provides a preset overcurrent threshold OCL0, which is not dynamically adjusted according to the system input current IIN. This indicates that the power stage 111 controlled by controller 115 may have lower thermal management requirements or specific operational needs.

[0034] In one embodiment, controllers 112-115 are each equipped with a switch control circuit 50 for generating multiple corresponding switch control signals. The switch control circuit 50 controls the switching devices of the corresponding power level based on the output voltage and overcurrent threshold of its corresponding phase, simultaneously regulating the output voltage and limiting the current of each phase. The memory 40 within each controller 112-115 stores the setting parameters of these thresholds to finely adjust the response characteristics of the corresponding power level. In one embodiment, the memory 40 of each controller 112-115 includes multiple registers. The memory 40 in controllers 112-114 stores the setting parameters of the dynamic overcurrent unit 30, while the memory 40 in controller 115 is used to determine the overcurrent threshold 0CL0.

[0035] like Figure 1B As shown, the system input current IIN is the output current of the DC / DC converter 107, which provides the total input current for the power stages 108 to 111. The current detection circuit 106 detects the system input current IIN.

[0036] Figures 1A-1B The multi-rail power supply system 100 shown illustrates how system input current sensing can be used to coordinate overcurrent limiting of multiple regulators. By dynamically adjusting the overcurrent threshold OCL, the multi-rail power supply system 100 achieves system-level thermal balance. Each power rail retains sufficient performance margin while total power consumption is controlled within safe limits to avoid overheating.

[0037] Figures 2A-2F An example curve for the overcurrent threshold OCL according to an embodiment of the present invention is shown. Those skilled in the art will understand that the characteristics of the overcurrent threshold OCL are not affected by... Figures 2A-2F Due to limitations, depending on the application scenario, the relationship between the overcurrent threshold OCL and the system input current IIN may conform to other curves. For example... Figure 2A As shown, when the system input current IIN is lower than the threshold Iref1, the overcurrent threshold OCL remains at the value LIMIT2. When the system input current IIN is higher than the threshold Iref1 but lower than the threshold Iref2, the overcurrent threshold OCL decreases with a certain slope as the system input current IIN increases. When the system input current IIN is higher than the threshold Iref2, the overcurrent threshold OCL remains at the value LIMIT1. Figures 2B-2D As shown, when the system input current IIN is higher than the threshold Iref1 but lower than the threshold Iref2, the overcurrent threshold OCL decreases non-linearly as the system input current IIN increases. Figure 2E As shown, the value LIMIT1 can be zero. Figure 2F As shown, both the value LIMIT1 and the threshold Iref1 can be zero.

[0038] Figure 3 A schematic diagram of a dynamic overcurrent unit 30A according to an embodiment of the present invention is shown. The dynamic overcurrent unit 30A provides an overcurrent threshold OCL based on a current sensing signal Iinsen, an initial overcurrent threshold OCLini, and an input current threshold Iinlimit. For example, when the current sensing signal Iinsen is lower than the input current threshold Iinlimit, the overcurrent threshold OCL remains at the initial overcurrent threshold OCLini. In another example, when the current sensing signal Iinsen is higher than the input current threshold Iinlimit, the overcurrent threshold OCL changes from the initial overcurrent threshold OCLini based on the difference (Iinlimit-Iinsen) between the input current threshold Iinlimit and the current sensing signal Iinsen.

[0039] Figure 4 A register mapping 400 according to an embodiment of the present invention is shown. This register mapping 400 can be stored in the memory 40 of the controllers 112-114. Figure 4As shown, register mapping 400 includes data OCL_MAX and data I_IN_LIMIT. Data OCL_MAX is used to set the initial overcurrent threshold OCLini. Data I_IN_LIMIT is used to set the input current threshold Iinlimit. When the current sensing signal Iinsen is higher than the input current threshold Iinlimit, the current threshold OCL is reduced.

[0040] Figure 5 A power limiting method 500 according to an embodiment of the present invention is shown. The power limiting method 500 includes steps S11 to S13, which can be executed by control circuits 112 to 114 equipped with register mapping 400.

[0041] In step S11, data OCL_MAX is read to set the initial overcurrent threshold OCLini, and data I_IN_LIMIT is read to set the input current threshold Iinlimit. In step S12, when the system input current IIN is lower than the threshold Iref1, causing the current detection signal Iinsen to be lower than the input current threshold Iinlimit, the overcurrent threshold OCL is equal to the initial overcurrent threshold OCLini. In step S13, when the system input current IIN is higher than the threshold Iref1, causing the current detection signal Iinsen to be higher than the input current threshold Iinlimit, the overcurrent threshold OCL will decrease from the initial overcurrent threshold OCLini.

[0042] Figure 6 A schematic diagram of a dynamic overcurrent unit 30B according to an embodiment of the present invention is shown. In one embodiment, the dynamic overcurrent unit 30B further sets an overcurrent threshold OCL based on a minimum overcurrent threshold OCLMin. When the current sensing signal Iinsen is higher than the input current threshold Iinlimit, the overcurrent threshold OCL continuously decreases until it reaches the minimum overcurrent threshold OCLMin, after which the overcurrent threshold OCL will remain constant at the minimum overcurrent threshold OCLMin and will no longer decrease. In another embodiment, the dynamic overcurrent unit 30B further sets the overcurrent threshold OCL based on a decreasing rate SLOPE. When the current sensing signal Iinsen increases to above the input current threshold Iinlimit, the overcurrent threshold OCL will decrease at a decreasing rate SLOPE.

[0043] Figure 7Register mapping 700 according to an embodiment of the present invention is illustrated. Compared to register mapping 400, register mapping 700 further includes data OCL_MIN and data OCL_SLOPE. Data OCL_MIN is used to set the minimum overcurrent threshold OCLMin. Data OCL_SLOPE is used to set the rate of decrease SLOPE of the overcurrent threshold OCL. Register mapping 700 also includes data DOCL_EN for controlling the enabled state of the dynamic overcurrent limiting function. When the dynamic overcurrent limiting function is enabled, the overcurrent threshold OCL is dynamically adjusted according to the system input current IIN. When the dynamic overcurrent limiting function is disabled, the overcurrent threshold OCL remains at the initial value OCLini and is no longer adjusted according to the system input current IIN. These additional registers enable the multi-rail power supply system 100 to achieve fine control of the dynamic overcurrent limit, allowing the regulator to respond more aggressively or conservatively to changes in overall power demand.

[0044] Figure 8 A power limiting method 800 according to an embodiment of the present invention is shown. The method 800 includes steps S21 to S26, which can be executed by control circuits 112 to 114 equipped with register mapping 700.

[0045] In step S21, data OCL_MAX is read to set the initial overcurrent threshold OCLini, data I_IN_LIMIT is read to set the input current threshold Iinlimit, data OCL_MIN is read to set the minimum overcurrent threshold OCLMin, and data OCL_SLOPE is read to set the rate of decrease SLOPE for the overcurrent threshold OCL. In step S22, it is determined whether the dynamic overcurrent protection function is enabled. If the function is disabled, step S23 is executed; if the function is enabled, steps S24 to S26 are executed. In step S23, the dynamic overcurrent protection function is disabled, and the overcurrent threshold OCL remains constant, for example, equal to the initial overcurrent threshold OCLini. In step S24, when the system input current IIN is lower than the threshold Iref1, the current detection signal Iinsen is lower than the input current threshold Iinlimit, and the overcurrent threshold OCL is equal to the initial overcurrent threshold OCLini. In step S25, when the system input current IIN is higher than the threshold Iref1, causing the current detection signal Iinsen to be higher than the input current threshold Iinlimit, the overcurrent threshold OCL will decrease from the initial value OCLini with a decreasing slope SLOPE. In step S26, the overcurrent threshold OCL continues to decrease until it decreases to the minimum overcurrent threshold OCLMin, at which point the overcurrent threshold OCL is locked at the minimum overcurrent threshold OCLMin.

[0046] Figure 9 A schematic diagram of a dynamic overcurrent unit 30C according to an embodiment of the present invention is shown. (Refer to...) Figure 9When the current sensing signal Iinsen is lower than the input current threshold Iinlimit, an overcurrent threshold OCL is generated based on the stored data OCL_MAX using a digital-to-analog converter (DAC) 33 and a resistor 35. A comparator 31 compares the current sensing signal Iinsen with the input current threshold Iinlimit. When the current sensing signal Iinsen is higher than the input current threshold Iinlimit, the current source 32 pulls down the overcurrent threshold OCL under the control of the output of comparator 31. DAC 36 provides a minimum overcurrent threshold OCLMin based on the stored data OCL_MIN. A clamping circuit 37 is configured to clamp the overcurrent threshold OCL to a level not lower than the minimum overcurrent threshold OCLMin.

[0047] In one example, comparator 38 compares the overcurrent threshold OCL with the current sense signal Iosen to generate an overcurrent indication signal OC. The current sense signal Iosen can represent the output current (e.g., Io1, Io2, Io3) or the phase current flowing through the switching circuit. When the current sense signal Iosen exceeds the overcurrent threshold OCL, the overcurrent indication signal OC is activated (e.g., a logic high level), indicating that an overcurrent condition has occurred. The controller can then respond by temporarily shutting down the power stage to keep the output current within a safe range.

[0048] Figure 10 A schematic diagram of a multiphase voltage regulator 1000 according to an embodiment of the present invention is shown. Figure 10 In the example, the multiphase voltage regulator 1000 is implemented by power stage 108 and controller 112. The design and working principle of the multiphase voltage regulator 1000 are provided as a reference embodiment. Other voltage regulators implemented by power stages 109-110 and corresponding controllers 113-114 in the multi-rail power supply system adopt the same structure, and will not be described in detail here for the sake of simplicity.

[0049] Power stage 108 includes multiphase circuit 1100 (i.e. Figure 10 The switch circuits shown are 1100-1, 1100-2, and 1100-3. Figure 10For example, power stage 108 uses a three-phase circuit design. The number of phases can be increased or decreased as needed in other applications. Each phase circuit includes a high-side switch S1, a low-side switch S2, a switching node SW formed by the high-side switch S1 and the low-side switch S2, an output inductor LOUT connected between the switching node SW and the output node 102, and a driver 1101. The driver 1101 is configured to control the on and off of the high-side switch S1 and the low-side switch S2 based on corresponding switching control signals (PWM1_1, PWM1_2, PWM1_3). Phase current Iph1 represents the current flowing through phase circuit 1100-1, phase current Iph2 represents the current flowing through phase circuit 1100-2, and phase current Iph3 represents the current flowing through phase circuit 1100-3.

[0050] In one embodiment, the switch control circuit 50 generates switch control signals PWM1_1, PWM1_2, and PWM1_3 based on the overcurrent threshold OCL, the output voltage Vo1, and the phase currents Iph1 to Iph3. In another embodiment, the switch control circuit 50 receives a voltage detection signal Vosn1 indicating the output voltage Vo1, a current detection signal CS1 indicating the phase current Iph1, a current detection signal CS2 indicating the phase current Iph2, and a current detection signal CS3 indicating the phase current Iph3, and provides switch control signals PWM1_1, PWM1_2, and PWM1_3 to adjust the output voltage Vo1, while limiting the phase currents (Iph1, Iph2, and Iph3) to be less than the overcurrent threshold OCL.

[0051] In another example, the total phase current Isum (i.e., Iph1+Iph2+Iph3) provided by phase circuit 1100 is also limited based on the overcurrent threshold OCL. Switch control circuit 50 receives a current detection signal Imon indicating the total phase current Isum, and further generates switch control signals PWM1_1, PWM1_2, and PWM1_3 based on the current detection signal Imon.

[0052] Figure 11A schematic diagram of a switch control circuit 50A according to an embodiment of the present invention is shown. The switch control circuit 50A includes comparators 201 to 203. Comparator 201 generates an overcurrent indication signal OC1 based on a current detection signal CS1 and an overcurrent threshold OCL. When the current detection signal CS1 exceeds the overcurrent threshold OCL, the overcurrent indication signal OC1 is valid, indicating that phase circuit 1100-1 is in an overcurrent state. Comparator 202 generates an overcurrent indication signal OC2 based on a current detection signal CS2 and an overcurrent threshold OCL. When the current detection signal CS2 exceeds the overcurrent threshold OCL, the overcurrent indication signal OC2 is valid, indicating that phase circuit 1100-2 is in an overcurrent state. Comparator 203 generates an overcurrent indication signal OC3 based on a current detection signal CS3 and an overcurrent threshold OCL. When the current detection signal CS3 exceeds the overcurrent threshold OCL, the overcurrent indication signal OC3 is valid, indicating that phase circuit 1100-3 is in an overcurrent state. Output circuit 206 provides switch control signals PWM1_1, PWM1_2, and PWM1_3 based on overcurrent indication signals OC1-OC3 and a setting signal SET. The setting signal SET is generated based on the difference or comparison result between the feedback signal Vfb (indicating output voltage Vo1) and the reference signal Vref. In one embodiment, feedback circuit 207 receives a voltage detection signal Vosn1 and generates the feedback signal Vfb based on this signal. Comparator or amplifier 205 is configured to provide the setting signal SET. When the overcurrent indication signals OC1-OC3 are invalid, the switch control signals PWM1_1, PWM1_2, and PWM1_3 are generated in response to the setting signal SET and are used to adjust the output voltage Vo1. When any of the overcurrent indication signals OC1-OC3 is valid, the corresponding switch control signal turns off the corresponding phase circuit. For example, when the overcurrent indication signal OC1 is valid (indicating that the current detection signal CS1 exceeds the overcurrent threshold OCL), the state of the switch control signal PWM1_1 becomes invalid to turn off the phase circuit 1100-1 (e.g., turn off the high-side switch S1), or to keep the switch control signal PWM1_1 in an invalid state until the overcurrent state of the phase circuit 1100-1 is eliminated.

[0053] Figures 12A-12C A timing diagram of a switch control circuit 50A according to an embodiment of the present invention is shown. Figure 12A As shown, the peak values ​​of each current detection signal CS1 to CS3 are constrained by the overcurrent threshold OCL. Figure 12B As shown, the valley values ​​of each current detection signal CS1 to CS3 are constrained by the overcurrent threshold OCL. Figure 12C As shown, the average values ​​of each current detection signal CS1 to CS3 are constrained by the overcurrent threshold OCL.

[0054] Figure 13A schematic diagram of a switch control circuit 50B according to an embodiment of the present invention is shown. The switch control circuit 50B further includes a comparator 204. The comparator 204 generates an overcurrent indication signal OCtotal based on a current detection signal Imon and an overcurrent threshold Imon_th. In one example, the current detection signal Imon is generated based on the sum of current detection signals CS1 to CS3. The output circuit 206 further provides switch control signals PWM1_1, PWM1_2, and PWM1_3 based on the overcurrent indication signal OCtotal. When the overcurrent indication signal OCtotal is valid (indicating that the current detection signal exceeds the overcurrent threshold Imon_th), all switch control signals PWM1_1, PWM1_2, and PWM1_3 are invalid, keeping all phase circuits 1100-1, 1100-2, and 1100-3 in the off state. The switch control signals PWM1_1, PWM1_2, and PWM1_3 resume normal operation to regulate the output voltage Vo1 only when the state of the overcurrent indication signal OCtotal becomes invalid (indicating that the overcurrent condition is resolved).

[0055] Figure 14 A timing diagram of a multiphase voltage regulator 1000 according to an embodiment of the present invention is shown. Figure 14 The following parameters are shown from top to bottom: (i) output voltage Vo1, (ii) total phase current Isum, and (iii) overcurrent threshold OCL. The dashed line represents the output voltage Vo1 when the dynamic overcurrent limiting function is disabled, in which case the overcurrent threshold OCL remains constant. When the dynamic overcurrent limiting function is enabled, the overcurrent threshold OCL varies with the system input current IIN, while the total phase current Isum is limited by the variable overcurrent threshold OCL, which is determined by the system input current IIN. Enabling the dynamic overcurrent limiting function results in a more significant decrease in the output voltage Vo1 compared to disabling it. Figure 14 As shown, at time t1, the load draws a higher output current Io1. At this time, the overcurrent threshold OCL decreases, causing the total phase current Isum to be limited by the reduced overcurrent threshold OCL. Consequently, the output voltage Vo1 decreases, thus limiting the output power.

[0056] Figure 15 A control method 1500 for a multiphase voltage regulator according to an embodiment of the present invention is shown. The control method 1500 includes steps S31 to S33. The multiphase voltage regulator includes a power stage composed of multiphase circuits and a controller.

[0057] In step S31, the system input current is detected, which indicates the total input current of the multiphase regulator and at least one other regulator, and a current detection signal is provided. In step S32, the overcurrent threshold of the multiphase regulator is dynamically set based on the current detection signal. In step S33, the current of each phase is limited based on the overcurrent threshold.

[0058] Although the invention has been described with reference to several exemplary embodiments, it should be understood that the terminology used is descriptive and exemplary, and not restrictive. Since the invention can be embodied in many forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims. Therefore, all variations and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. A controller for a multiphase voltage regulator in a multi-rail power supply system, comprising: A dynamic overcurrent unit is configured to provide an overcurrent threshold based on the system input current, wherein the system input current indicates the total input current of the multiphase voltage regulator and at least one other voltage regulator; as well as A switching control circuit is configured to provide multiple switching control signals to control multiple switching circuits of the multiphase voltage regulator, thereby adjusting the output voltage of the multiphase voltage regulator to a preset level and controlling the output current of the multiple switching circuits based on the overcurrent threshold.

2. The controller of claim 1, wherein the controller is configured to limit the current output by each of the plurality of switching circuits in response to the overcurrent threshold.

3. The controller as claimed in claim 1, wherein: In response to the system input current being less than a first threshold, the overcurrent threshold is maintained at a first value; and In response to the system input current being higher than the first threshold, the overcurrent threshold decreases as the system input current increases.

4. The controller of claim 1, further comprising: The memory is configured to store first data for setting an initial overcurrent threshold and second data for setting an input current threshold. in The dynamic overcurrent unit is configured to receive a current detection signal indicating the system input current, the initial overcurrent threshold, and the input current threshold, and to provide the overcurrent threshold in response to the current detection signal, the initial overcurrent threshold, and the input current threshold.

5. The controller as claimed in claim 4, wherein: In response to the current detection signal being less than the input current threshold, the overcurrent threshold remains at the initial overcurrent threshold; as well as In response to the current detection signal being higher than the input current threshold, the overcurrent threshold changes from the initial overcurrent threshold based on the difference between the input current threshold and the current detection signal.

6. The controller of claim 4, wherein the memory is further configured to store third data for setting a minimum overcurrent threshold, the minimum overcurrent threshold being used to set a minimum value of the overcurrent threshold.

7. The controller of claim 4, wherein the memory is further configured to store fourth data, wherein the fourth data is used to set the rate of decrease of the overcurrent threshold.

8. The controller of claim 1, wherein the dynamic overcurrent unit comprises: A first digital-to-analog converter is configured to provide an initial overcurrent threshold based on first data; Current source; as well as A comparator is configured to compare a current detection signal indicating the system input current with an input current threshold. in When the current detection signal is higher than the input current threshold, the current source pulls down the overcurrent threshold under the control of the comparator output.

9. The controller of claim 8, wherein the dynamic overcurrent unit further comprises: The second digital-to-analog converter is configured to provide a minimum overcurrent threshold based on the second data; as well as A clamping circuit is configured to clamp the overcurrent threshold to a level not lower than the minimum overcurrent threshold.

10. The controller of claim 1, further comprising: Multiple comparison circuits are configured to compare multiple phase current detection signals with the overcurrent threshold respectively to provide multiple overcurrent indication signals; in In response to one of the plurality of phase current detection signals being higher than the overcurrent threshold, the controller shuts off the corresponding switching circuit.

11. A control method for a multiphase voltage regulator in a multi-rail power supply system, comprising: Provide an overcurrent threshold; Multiple switching control signals are provided to control multiple switching circuits of the multiphase voltage regulator, so that the output voltage of the multiphase voltage regulator is adjusted to a preset level, and the output current of the multiple switching circuits is controlled based on the overcurrent threshold. as well as In response to the activation of the dynamic overcurrent limiting function, the overcurrent threshold is dynamically adjusted based on the system input current, wherein the system input current indicates the total input current of the multiphase regulator and at least one other regulator.

12. The control method of claim 11, further comprising: In response to the dynamic overcurrent limiting function being disabled, the overcurrent threshold is maintained constant.

13. The control method of claim 11, further comprising: In response to the overcurrent threshold, the current supplied by each of the plurality of switching circuits is limited.

14. The control method of claim 11, further comprising: Receive a current detection signal indicating the input current of the system; When the current detection signal is less than the input current threshold, the overcurrent threshold is maintained at the initial overcurrent threshold. as well as When the current detection signal is higher than the input current threshold, the overcurrent threshold is controlled to decrease from the initial overcurrent threshold.

15. The control method of claim 14, further comprising: Read the first data to set the initial overcurrent threshold; as well as Read the second data to set the input current threshold.

16. The control method of claim 11, further comprising: Receive a current detection signal indicating the input current of the system; When the current detection signal is less than the input current threshold, the overcurrent threshold is maintained at the initial overcurrent threshold. as well as When the current detection signal is higher than the input current threshold, the overcurrent threshold is changed according to the difference between the input current threshold and the current detection signal.

17. A multi-rail power supply system, comprising: The first regulator includes an input node, an output node configured to provide a first output voltage, a first set of multiple switching circuits, and a first controller; as well as The second regulator, wherein the first regulator includes an input node and an output node configured to provide a second output voltage, the input node of the first regulator being coupled to the input node of the second regulator; in The first controller is configured to dynamically set a first overcurrent threshold based on the system input current to limit the current flowing through each of the first group of multiple switching circuits, wherein the system input current indicates the total input current of at least the first regulator and the second regulator.

18. The multi-rail power supply system of claim 17, wherein the first controller further comprises: The dynamic overcurrent unit is configured to provide an overcurrent threshold based on the system input current; as well as A switch control circuit is configured to provide a plurality of switch control signals to control the first group of multiple switch circuits, thereby regulating the first output voltage, and is configured to limit the current flowing through each of the first group of multiple switch circuits based on the overcurrent threshold.

19. The multi-rail power supply system of claim 17, wherein the second voltage regulator further comprises: A second set of multiple switching circuits and a second controller, the second controller being configured to dynamically set a second overcurrent threshold based on the system input current to limit the current flowing through each of the multiple switching circuits in the second set.

20. The multi-rail power supply system as described in claim 17, wherein: When the system input current is less than a first threshold, the first overcurrent threshold remains at a first value; and When the system input current is greater than the first threshold, the first overcurrent threshold decreases as the system input current increases.

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