Power management circuit, power management chip and control method

Abstract

The invention provides a power supply management circuit, a power supply management module and a control method, the power supply management circuit comprises a first control module, a feedback circuit and a plurality of voltage stabilization working circuits, one of the plurality of voltage stabilization working circuits is a low dropout linear voltage stabilization circuit, and the other voltage stabilization working circuits are DC-DC conversion circuits; the first control module is used for outputting a first control signal to the feedback circuit; the feedback circuit is used for being connected to the target voltage stabilization working circuit according to the first control signal; the feedback circuit is used for sampling the real-time power supply voltage output by the target voltage-stabilizing working circuit to obtain corresponding feedback voltage and outputting the feedback voltage to the target voltage-stabilizing working circuit; and the target voltage-stabilizing working circuit is used for adjusting the power supply voltage according to the feedback voltage so as to output stable power supply voltage. The circuit can adapt to wide-range voltage input and output, has the adjusting capability, and can meet the power supply requirement in a multi-module power supply scene in an integrated circuit.

Description

Technical Field

[0001] The present invention belongs to the technical field of integrated circuits, and in particular relates to a power management circuit, a power management chip and a control method. Background Art

[0002] Both DC-DC converters and low dropout linear regulators (LDO) are voltage converters that can effectively output a stable voltage after converting the input voltage. They are widely used in chips as power management modules.

[0003] Common conversion topologies of DC-DC converters include boost, buck, buck-boost, etc. There are various feedback control modes according to requirements, such as voltage control mode, current control mode, hysteresis control mode, etc. Under different feedback control modes, the voltage conversion efficiency, voltage ripple and high-speed load transient response speed of the DC-DC converter are different.

[0004] Low-dropout linear regulators adjust the voltage difference within their operating range through transistors, and can reduce high input voltage to a stable output voltage. Compared with DC-DC converters, low-dropout linear regulators have lower voltage conversion efficiency than DC-DC converters. In the case of high input-output voltage difference, low-dropout linear regulators have greater energy loss, but their voltage output is stable, with low noise and high precision.

[0005] At present, a single output of a DC-DC converter or a low voltage dropout linear regulator can no longer meet the power supply requirements of different modules of analog circuits and digital circuits in a chip in various power supply scenarios. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a power management circuit, a power management chip and a control method, aiming to solve the problem that a single output of a DC-DC converter or a low voltage drop linear regulator is difficult to meet the current power supply demand.

[0007] To solve the above technical problems, the present invention is implemented as follows: a power management circuit includes a first control module, a feedback circuit and a plurality of voltage stabilization working circuits, one of the plurality of voltage stabilization working circuits is a low voltage difference linear voltage stabilization circuit, and the other voltage stabilization working circuits are DC-DC conversion circuits; The first control module is used to output a first control signal to the feedback circuit; The feedback circuit is used to connect to the target voltage stabilization working circuit according to the first control signal; The feedback circuit is used to sample the real-time power supply voltage output by the target voltage stabilization working circuit, obtain a corresponding feedback voltage, and output the feedback voltage to the target voltage stabilization working circuit; The target voltage stabilization working circuit is used to adjust the power supply voltage according to the feedback voltage to output a stable power supply voltage.

[0008] Furthermore, the power management circuit also includes a second control module; The second control module is used to output a second control signal to the feedback circuit; The feedback circuit is used to adjust the load resistance of the feedback circuit according to the second control signal, and then sample the real-time power supply voltage output by the target voltage stabilization working circuit according to the corresponding load resistance to obtain a corresponding feedback voltage.

[0009] Further, the first control module includes a plurality of inverters and a plurality of AND gates; Each of the inverters is used to receive a binary control code; Each of the AND gates is used to generate the first control signal according to the binary control code, and then output the first control signal to the feedback circuit.

[0010] Further, the target voltage stabilization working circuit includes a voltage control circuit, a switch circuit and a load circuit; the voltage control circuit includes a first error amplifier, a first reference voltage source, a first comparator and a voltage controlled oscillator; The feedback circuit is used to sample the real-time power supply voltage output by the load circuit to obtain a corresponding feedback voltage; The first error amplifier is used to compare the feedback voltage with a first reference voltage generated by the first reference voltage source, and output a first error signal according to the comparison result; The first comparator is used to compare the first error signal with the ramp signal generated by the voltage controlled oscillator, and output a first pulse width modulation signal according to the comparison result; The switch circuit is used to adjust the power supply voltage according to the first pulse width modulation signal to output a corresponding output voltage; The load circuit is used to adjust the output voltage to output a stable supply voltage.

[0011] Further, the target voltage stabilization working circuit includes a hysteresis control circuit, a switch circuit and a load circuit; the hysteresis control circuit includes a second comparator and a second reference voltage source; When the feedback circuit is connected to the second DC-DC conversion circuit according to the first control signal: The feedback circuit is used to sample the real-time power supply voltage output by the load circuit to obtain a corresponding feedback voltage; The second comparator is used for comparing the feedback voltage with the second reference voltage generated by the second reference voltage source, and outputting a second pulse width modulation signal according to the comparison result; The switch circuit is used to adjust the power supply voltage according to the second pulse width modulation signal to output a corresponding output voltage; The load circuit is used to adjust the output voltage to output a stable supply voltage.

[0012] Furthermore, the target voltage stabilization working circuit also includes an overcurrent protection module; The input end of the overcurrent protection module is electrically connected to the output end of the feedback circuit, and the output end of the zero-crossing detection module is electrically connected to the input end of the switch circuit.

[0013] Furthermore, the target voltage stabilization working circuit also includes a zero-crossing detection module; The input end of the zero-crossing detection module is electrically connected to the output end of the feedback circuit, and the output end of the zero-crossing detection module is electrically connected to the input end of the switch circuit.

[0014] The present invention also provides a power management chip, comprising the power management circuit as described above.

[0015] The present invention also provides a control method for a power management circuit, wherein the power management circuit comprises a first control module, a feedback circuit and a plurality of voltage stabilization circuits, wherein one of the plurality of voltage stabilization circuits is a low voltage difference linear voltage stabilization circuit, and the other voltage stabilization circuits are DC-DC conversion circuits; The first control module outputs a first control signal to the feedback circuit; The feedback circuit is connected to the target voltage stabilization working circuit according to the first control signal; The feedback circuit samples the power supply voltage output by the target voltage stabilization working circuit to obtain a corresponding feedback voltage, and outputs the feedback voltage to the target voltage stabilization working circuit; The target voltage stabilization working circuit adjusts the power supply voltage according to the feedback voltage to output a stable power supply voltage.

[0016] Furthermore, the power management circuit further includes a second control module; and the method further includes: The second control module outputs a second control signal to the feedback circuit; The feedback circuit samples the supply voltage output by the target voltage stabilization working circuit to obtain a corresponding feedback voltage, including: The feedback circuit adjusts the load resistance of the feedback circuit according to the second control signal, and then samples the real-time power supply voltage output by the target voltage stabilization working circuit according to the corresponding load resistance to obtain a corresponding feedback voltage.

[0017] Compared with the prior art, the power management circuit, power management chip and control method in the present invention have the following beneficial effects: The power management circuit in the present invention integrates a variety of voltage stabilization working circuits, one of which is a low voltage difference linear voltage stabilization circuit, and the rest are DC-DC conversion circuits. The first control module can control the feedback circuit to access the target voltage stabilization working circuit, so that the target voltage stabilization working circuit forms a loop with feedback function, and then realizes the voltage stabilization power supply of the power management circuit. The voltage conversion efficiency, transient response speed, voltage ripple and stability of the various voltage stabilization working circuits are different, so that the power management circuit can adapt to a wide range of voltage input and output, and has the ability to adjust voltage ripple, transient response speed and accuracy, which can meet the power supply requirements in the multi-module power supply scenario in the integrated circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is an overall circuit block diagram of a power management circuit in an embodiment of the present invention; Figure 2 is a circuit block diagram of the actual operation of the power management circuit in the voltage control mode according to an embodiment of the present invention; Figure 3 is a circuit block diagram of the actual operation of the power management circuit in the hysteresis control mode in an embodiment of the present invention; Figure 4 is a circuit block diagram of the actual operation of the power management circuit in the hysteresis control mode in an embodiment of the present invention; Figure 5 is a circuit diagram of a power management circuit in an embodiment of the present invention; Figure 6 is an equivalent circuit diagram of a power management circuit in an embodiment of the present invention; Figure 7 is a circuit diagram of a DC-DC conversion circuit in a voltage control mode according to an embodiment of the present invention; Figure 8 is a circuit diagram of a DC-DC conversion circuit in a hysteresis control mode in an embodiment of the present invention; Fig. 9 is a circuit diagram of a DC-DC conversion circuit in an LDO mode in an embodiment of the present invention; Fig.10 is a circuit diagram of a first control module in an embodiment of the present invention; Fig.11 It is a basic flow chart of the control method of the power management circuit in the embodiment of the present invention.

[0019] In the accompanying drawings, each reference numeral represents: 100, low voltage difference linear voltage regulator circuit; 210, voltage control circuit; 220, hysteresis control circuit; 230, switch circuit; 240, load circuit; 310, switch unit; 320, resistor array unit. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] Example: See also Figures 1 to 10 In this embodiment, a power management circuit includes a first control module, a feedback circuit and a plurality of voltage stabilizing working circuits, one of the plurality of voltage stabilizing working circuits is a low voltage difference linear voltage stabilizing circuit 100, and the other voltage stabilizing working circuits are DC-DC conversion circuits; The first control module is used to output a first control signal to the feedback circuit; The feedback circuit is used to connect to the target voltage stabilization working circuit according to the first control signal; The feedback circuit is used to sample the real-time power supply voltage output by the target voltage stabilization working circuit, obtain a corresponding feedback voltage, and output the feedback voltage to the target voltage stabilization working circuit; The target voltage regulation working circuit is used to regulate the power supply voltage according to the feedback voltage to output a stable supply voltage.

[0022] The power management circuit in this embodiment integrates multiple voltage stabilization working circuits. The first control module can control the feedback circuit to access different voltage stabilization working circuits, so that the corresponding voltage stabilization working circuits form a loop with feedback function, and then realize the voltage stabilization power supply of the power management circuit. The voltage conversion efficiency, transient response speed, voltage ripple and stability of the various voltage stabilization working circuits are different, so that the power management circuit can adapt to a wide range of voltage input and output, and has the ability to adjust voltage ripple, transient response speed and accuracy, which can meet the power supply requirements in the multi-module power supply scenario in the integrated circuit.

[0023] One of the multiple voltage stabilization working circuits is a low voltage difference linear voltage stabilization circuit 100, and the rest are DC-DC conversion circuits. The DC-DC circuit has corresponding control modes based on different circuit structures, such as: pulse width modulation (PWM) control mode, pulse frequency modulation (PFM) control mode, voltage control mode, current control mode or hysteresis control mode. It can be understood that the control modes of several DC-DC circuits in the multiple voltage stabilization working circuits can be the same or different. In the power management circuit of this embodiment, two DC-DC conversion circuits are preferably integrated.

[0024] Preferably, Figure 1 As shown, the feedback circuit includes a switch unit, a first control module is used to output a first control signal to the switch unit, and the switch unit is used to trigger a corresponding gating state according to different first control signals. In different gating states, the feedback circuit is connected to the target voltage stabilization working circuit.

[0025] In this embodiment, the switch unit includes an output port and multiple input ports S1, S2 and S3.

[0026] Preferably, the multiple voltage stabilization working circuits of the power management circuit in this embodiment are respectively the voltage control circuit 210, the hysteresis control circuit 220 and the low voltage difference linear voltage stabilization circuit 100, and the power management circuit includes multiple working modes corresponding to each voltage stabilization working circuit, and the multiple working modes are respectively the voltage control mode corresponding to the voltage control circuit 210, the hysteresis control mode corresponding to the hysteresis control circuit 220 and the LDO mode corresponding to the low voltage difference linear voltage stabilization circuit 100. Figures 2 to 4 The circuit diagrams of the power management circuit in the voltage control mode, hysteresis control mode and LDO mode are respectively, the solid line part is the target voltage stabilization circuit currently in operation, the dotted line part is the voltage stabilization circuit without the feedback circuit connected, and these voltage stabilization circuits are in a non-operating state. By inputting a first control signal to the feedback circuit, the feedback circuit is controlled to be connected to the voltage control circuit 210, the hysteresis control circuit 220 or the low voltage difference linear voltage stabilization circuit 100, so that the power management circuit enters the corresponding operating mode.

[0027] In addition, it should be known that the DC-DC circuit and the low voltage difference linear voltage regulator circuit 100 of the power management circuit of the related technology are mostly independent feedback regulation. In particular, the circuit complexity of the DC-DC circuit is relatively high, which makes the manufacturing, testing and debugging costs of the power management chip obtained by packaging the power management circuit relatively high. Due to cost constraints, it is difficult to integrate multiple DC-DC circuits with different working modes in the power management circuit, and the adaptability of the power management circuit under different power supply requirements is relatively poor.

[0028] Therefore, this embodiment designs a multi-loop power management circuit. In the power management circuit, multiple voltage regulation working circuits share the feedback circuit in the low voltage difference linear voltage regulation circuit 100. When the feedback circuit is not connected to the low voltage difference linear voltage regulation circuit 100, but is connected to any DC-DC circuit, the feedback circuit can provide feedback voltage for the corresponding DC-DC circuit.

[0029] Preferably, in this embodiment, the feedback voltage of the feedback circuit can also be controlled so that the voltage stabilization circuit can achieve a change in the output power supply voltage.

[0030] In this embodiment, if Figure 1 As shown, the power management circuit also includes a second control module; The second control module is used to output a second control signal to the feedback circuit; The feedback circuit is used to adjust the load resistance of the feedback circuit according to the second control signal, and then sample the real-time power supply voltage output by the target voltage stabilization working circuit according to the corresponding load resistance to obtain a corresponding feedback voltage.

[0031] like Figure 1 As shown, the feedback circuit further includes a resistor array unit 320; The second control module is used to output a second control signal to the resistor array unit 320, and the resistor array unit 320 is used to adjust the resistance value between the ground terminal connected to the target voltage stabilization working circuit and the feedback circuit according to the second control signal, and then sample the real-time power supply voltage output by the target voltage stabilization working circuit according to the corresponding resistance value to obtain the corresponding feedback voltage.

[0032] Preferably, Figure 5 As shown, the resistor array unit 320 includes a plurality of adjustable resistors.

[0033] The second control module is used to generate a five-bit control code TRIM<4:0>, and input the five-bit control code TRIM<4:0> to multiple adjustable resistors to control the resistance changes of the multiple adjustable resistors, so that the feedback circuit outputs different feedback voltages, and the corresponding voltage stabilization working circuit further adjusts according to the feedback voltage to output the supply voltage.

[0034] For the DC-DC conversion circuit in the multiple voltage stabilization working circuits, the feedback voltage regulation voltage control circuit 210 or the hysteresis control circuit 220 outputs a pulse width modulation signal (PWM), and the output stable power supply voltage is adjusted by changing the duty cycle. The stable power supply voltage VOUT is expressed as:

[0035] For the low voltage drop linear voltage regulator circuit 100, the stable supply voltage VOUT is expressed as:

[0036] In this embodiment, the resistor array unit 320 includes a first adjustable resistor RF1 and a second adjustable resistor RF2. The feedback voltage obtained by voltage division of the adjustable resistors is:

[0037] The five-bit control code TRIM<4:0> adjusts the resistance values ​​of the first adjustable resistor RF1 and the second adjustable resistor RF2, and ultimately enables the stable power supply voltage VOUT output in each working mode to generate a 32-bit multi-level output at most.

[0038] It should be understood that in this embodiment, the second control module is a microcontroller. In other embodiments, the second control module can output other control codes and is not limited to generating only the five-bit control code TRIM<4:0> or using only one microcontroller. The second control signal can also be output through the conversion of multiple control codes using multiple microcontrollers.

[0039] In addition, the second control module can also be a detection control module. The second control module can monitor the power supply voltage in real time, output a control logic signal by comparing the power supply voltage with a preset reference voltage, and automatically switch the voltage stabilizing output circuit connected to the feedback circuit according to different power supply stages or according to different power supply voltages, to ensure that the power management circuit stably outputs the power supply voltage, reduce the fluctuation of the power supply voltage during the power-on stage and the influence of the power supply voltage on the voltage stabilizing working circuit during the power supply process.

[0040] Furthermore, the resistor array unit 320 may be composed of a plurality of adjustable resistors, or may be composed of a plurality of fixed resistors and a switch unit connected in series and parallel with the plurality of fixed resistors. The resistance value of the resistance path in the feedback resistor may also be changed by controlling the switch unit to be turned on or off.

[0041] Furthermore, if Figure 6 As shown, the first control module includes a plurality of inverters and a plurality of AND gates; Each inverter is used to receive a binary control code; Each AND gate is used to generate a first control signal according to a binary control code, and then output the first control signal to the feedback circuit.

[0042] Preferably, the first control module includes N inverters and N+1 AND gates, where N is a positive integer and N≥3.

[0043] In this embodiment, if Figure 6 As shown, the first control module includes a first inverter, a second inverter, a third inverter, a first AND gate, a second AND gate, a third AND gate, and a fourth AND gate.

[0044] The input end of the first inverter is electrically connected to the input end of the third AND gate, the output end of the first inverter is electrically connected to the input end of the first AND gate, the input end of the second inverter is electrically connected to the input end of the first AND gate and the input end of the third AND gate, the output end of the second inverter is electrically connected to the input end of the second AND gate and the input end of the fourth AND gate, the input end of the third inverter is electrically connected to the input end of the second AND gate, and the output end of the third inverter is electrically connected to the input end of the fourth AND gate.

[0045] Each inverter receives a binary control code SEL<2:0>, and the input terminal of the first inverter receives SEL <0> , the input end of the second inverter receives SEL <2> , the input end of the third inverter receives SEL <1> The output ends of the first AND gate, the second AND gate, the third AND gate and the fourth AND gate output S1_EN, S2_EN, S3_EN and SHUTDOWN respectively.

[0046] The control logic expression of the first control module is:

[0047]

[0048]

[0049]

[0050] When the first control signal output S1_EN is valid, the switch S1 is turned on, the feedback circuit is connected to the voltage control circuit 210, and the power management circuit is in voltage control mode; When the first control signal output S2_EN is valid, the switch S2 is turned on, the feedback circuit is connected to the hysteresis control circuit 220, and the power management circuit is in the hysteresis control mode; When the first control signal output S3_EN is valid, the switch S3 is turned on, the feedback circuit is connected to the low voltage difference linear voltage regulator circuit 100, and the power management circuit is in LDO mode; When the SHUTDOWN output by the first control signal is valid, the switches S1, S2 and S3 are all turned off, the feedback circuit is disconnected from all voltage stabilization working circuits, and the power management circuit is turned off.

[0051] The mode selection truth table of the first control module is shown in Table 1 below: Table 1

[0052] The first control module performs logical operations according to the binary control code to output the first control signal to control the mode switching of the power management circuit. Such a setting can reduce the number of switches, reduce the complexity of the control circuit, and improve the stability of the power management circuit. The use of binary control codes also simplifies the control logic of the feedback circuit.

[0053] Furthermore, when the power management circuit is in voltage control mode, such as Figure 7 and 8 As shown, the target voltage stabilization working circuit includes a voltage control circuit 210, a switch circuit 230 and a load circuit 240; the voltage control circuit 210 includes a first error amplifier EA1, a first reference voltage source VREF GEN, a first comparator COMP1 and a voltage controlled oscillator VRGEN_OSC; The feedback circuit is used to sample the real-time power supply voltage output by the load circuit 240 to obtain a corresponding feedback voltage; The first error amplifier EA1 is used for comparing the feedback voltage with the first reference voltage generated by the first reference voltage source VREF GEN, and outputting a first error signal according to the comparison result; The first comparator COMP1 is used to compare the first error signal with the ramp signal generated by the voltage controlled oscillator VRGEN_OSC, and output a first pulse width modulation signal according to the comparison result; The switch circuit 230 is used to adjust the power supply voltage according to the first pulse width modulation signal to output a corresponding output voltage; The load circuit 240 is used to adjust the output voltage to output a stable supply voltage.

[0054] Specifically, Figure 7 As shown, the switch circuit 230 includes a PWM drive module (PWM DRIVER), a first MOS tube M1 and a second MOS tube M2, and the load circuit 240 includes an inductor L and a capacitor C; The PWM driving module outputs pulse signals with different duty cycles according to the first pulse width modulation signal, and the first MOS tube M1 and the second MOS tube M2 are turned on or off according to the pulse signal. The first MOS tube M1 or the second MOS tube M2 outputs current to the load circuit 240, and the load circuit 240 outputs the power supply voltage VOUT through energy storage and energy release. It can be understood that in the voltage control mode, the stable power supply voltage VOUT is determined by the duty cycle of the pulse signal. Decide, .

[0055] The working process of the voltage control mode of the power management circuit is as follows: the SEL input by the first control module <2> Set to 1, the feedback circuit is connected to the voltage control circuit 210, the power management circuit enters the voltage control mode of DC-DC conversion, and controls the switch tubes M1 and M2 to switch alternately through the PWM drive module to generate a power supply voltage VOUT with a certain voltage ripple. The adjustable control code TRIM<4:0> is used to adjust the resistance of the adjustable resistors RF1 and RF2, adjust the feedback voltage output by the feedback circuit, and further adjust the duty cycle of the pulse signal according to the feedback voltage , generating different stable supply voltages. In the voltage control mode, the working efficiency of the power management circuit is higher than that of other working modes, with low power consumption and strong stability.

[0056] Preferably, Figure 8 As shown, the voltage control circuit 210 also includes a differential loop and an integral loop. The differential loop, the integral loop and the first error amplifier EA1 form a three-type voltage compensation circuit. The input end of the differential loop is electrically connected to the output end of the feedback circuit, the output end of the differential loop and the input end of the integral loop are electrically connected to the negative input end of the first error amplifier EA1, and the output end of the integral loop is electrically connected to the negative input end of the first comparator COMP1.

[0057] The type III voltage compensation circuit adds two zero points and three poles to the voltage control circuit 210. By adjusting the resistance and capacitance values ​​of the type III voltage compensation circuit, the gain of the voltage control circuit 210 is increased, the transient characteristics of the voltage control circuit 210 are improved, and the influence of the conjugate poles of the voltage control circuit 210 is eliminated by utilizing the zero points.

[0058] In this embodiment, Figure 8 As shown, the differential loop includes a first resistor R1, a second resistor R3 and a first capacitor C2, and the integral loop includes a second capacitor C1, a third capacitor C3 and a third resistor R2.

[0059] Furthermore, when the power management circuit is in voltage control mode, such as Figure 7 and 9 As shown, the target voltage stabilization working circuit includes a hysteresis control circuit 220, a switch circuit 230 and a load circuit 240; the hysteresis control circuit 220 includes a second comparator COMP2 and a second reference voltage source VREF GEN; When the feedback circuit is connected to the second DC-DC conversion circuit according to the first control signal: The feedback circuit is used to sample the real-time power supply voltage output by the load circuit 240 to obtain a corresponding feedback voltage; The second comparator COMP2 is used for comparing the feedback voltage with the second reference voltage VREF3 generated by the second reference voltage source VREF GEN, and outputting a second pulse width modulation signal according to the comparison result; The switch circuit 230 is used to adjust the power supply voltage according to the second pulse width modulation signal to output a corresponding output voltage; The load circuit 240 is used to adjust the output voltage to output a stable supply voltage.

[0060] The working process of the hysteresis control mode of the power management circuit is as follows: the control code input to the first control module is set to SEL<2:0>=1×1, the feedback circuit is connected to the hysteresis control circuit 220, the power control circuit enters the hysteresis control mode of DC-DC conversion, and the PWM drive module controls the switch tubes M1 and M2 to switch alternately to generate a stable power supply voltage VOUT with a certain voltage ripple. Similarly, the second control module can adjust the feedback voltage output by the feedback circuit through the control code to generate different feedback voltages.

[0061] In the hysteresis control mode, the transient response speed of the power management circuit is high, and it can be applied to modules with low voltage ripple requirements and high current transient response requirements.

[0062] Furthermore, if Figure 7 and 10 As shown, the low voltage difference linear voltage regulator circuit 100 includes a third reference voltage source VREF GEN, a second error amplifier and a third switch tube M3; After the feedback circuit is connected to the low voltage difference linear voltage regulator circuit 100, the second error amplifier is used to compare the feedback voltage output by the feedback circuit with the third reference voltage VREF2 output by the third reference voltage source, and output an error signal according to the comparison result. The third switch tube M3 is used to output a stable supply voltage according to the error signal.

[0063] In LDO mode, the supply level of the power management circuit is:

[0064] The working process of the LDO mode of the power management circuit is as follows: the control code input to the first control module is SEL<2:0>=0×1, the feedback circuit is connected to the low voltage difference linear voltage regulator circuit 100, the power control circuit enters the LDO mode, and the third switch tube M3 outputs a stable power supply voltage. Through the control code output by the second control module, TRIM<4:0> adjusts the resistance values ​​of the adjustable resistors RF1 and RF2, adjusts the feedback voltage output by the feedback circuit, and through the negative feedback mode of the second error amplifier, the third switch tube M3 can output different stable power supply voltages according to different feedback voltages.

[0065] In LDO mode, the power management circuit has low noise and small voltage ripple, and can output precise and stable voltage, which can be well applied to usage scenarios such as analog circuits and sensor interfaces.

[0066] When the power management circuit is in hysteresis control mode, the power management circuit further includes a zero crossing detection module ZCD; After the feedback circuit is connected to the hysteresis control circuit 220 , the input end of the zero-crossing detection module ZCD is electrically connected to the output end of the feedback circuit, and the output end of the zero-crossing detection module ZCD is electrically connected to the input end of the switch circuit 230 .

[0067] In this embodiment, Figure 7 and 9 As shown, a node SW is provided between the switch circuit 230 and the load circuit 240, and the zero-crossing detection module ZCD is used to detect the voltage signal at the node SW, and whether the voltage signal at the node SW crosses zero makes the operation of the switch circuit 230 smoother, further reduces the transient overcurrent of the switch tube of the switch circuit 230 after turning on or off, reduces the electromagnetic interference and loss in the circuit, and protects the switch circuit 230 and the load circuit 240.

[0068] When the power management circuit is in voltage control mode or hysteresis control mode, such as Figure 7 and 8 As shown, the target voltage regulation working circuit also includes an over-current protection module OCP; After the feedback circuit is connected to the voltage control circuit 210 or the hysteresis control circuit 220 , the input end of the overcurrent protection module OCP is electrically connected to the output end of the feedback circuit, and the output end of the zero crossing detection module ZCD is electrically connected to the input end of the switch circuit 230 .

[0069] The overcurrent protection module OCP determines whether the corresponding power management circuit needs current limiting through current sampling of the SW node, which plays a role in protecting the power management circuit and increases the stability and reliability of the loop of the power management circuit in the voltage control mode and the hysteresis control mode.

[0070] In the second embodiment, a power management chip is provided. The power management chip is obtained by encapsulating the power management circuit in the first embodiment, and can adjust multiple working modes and is suitable for different power supply scenarios.

[0071] like Fig.11 As shown, the third embodiment provides a control method for a power management circuit, the power management circuit includes a first control module, a feedback circuit and a plurality of voltage stabilization working circuits, one of the plurality of voltage stabilization working circuits is a low voltage difference linear voltage stabilization circuit, and the other voltage stabilization working circuits are DC-DC conversion circuits; Step 111, the first control module outputs a first control signal to the feedback circuit; Step 112: the feedback circuit is connected to the target voltage stabilization working circuit according to the first control signal; Step 113: The feedback circuit samples the supply voltage output by the target voltage stabilization working circuit to obtain a corresponding feedback voltage, and outputs the feedback voltage to the target voltage stabilization working circuit; Step 114: The target voltage stabilization circuit adjusts the power supply voltage according to the feedback voltage to output a stable power supply voltage.

[0072] Furthermore, the power management circuit further includes a second control module; and the control method further includes: Step 121, the second control module outputs a second control signal to the feedback circuit; Step 111, the feedback circuit samples the supply voltage output by the target voltage stabilization working circuit to obtain a corresponding feedback voltage, including: Step 122: The feedback circuit adjusts the load resistance of the feedback circuit according to the second control signal, and then samples the real-time power supply voltage output by the target voltage stabilization working circuit according to the corresponding load resistance to obtain a corresponding feedback voltage.

[0073] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of modules is only a logical function division, and there may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0074] It should also be understood that the control method in the third embodiment can be applied to the power management circuit of the first embodiment. The third embodiment focuses on the method of the power management circuit. For the parts not described in detail in the third embodiment, refer to the relevant descriptions of other embodiments. Similarly, for the parts not described in detail in the second embodiment, refer to the relevant descriptions of other embodiments.

[0075] And since the first embodiment is only a preferred embodiment of the power management circuit, the control method in the third embodiment can also be applied to the power management circuit implemented by other equivalent replacements and improvements. Similarly, the chip in the second embodiment can also be packaged by the power management circuit implemented by other equivalent replacements and improvements.

[0076] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A power management circuit, characterized in that: It includes a first control module, a feedback circuit and a plurality of voltage stabilizing working circuits, one of the plurality of voltage stabilizing working circuits is a low voltage difference linear voltage stabilizing circuit, and the other voltage stabilizing working circuits are DC-DC conversion circuits; The first control module is used to output a first control signal to the feedback circuit; The feedback circuit is used to connect to the target voltage stabilization working circuit according to the first control signal; The feedback circuit is used to sample the real-time power supply voltage output by the target voltage stabilization working circuit, obtain a corresponding feedback voltage, and output the feedback voltage to the target voltage stabilization working circuit; The target voltage stabilization working circuit is used to adjust the power supply voltage according to the feedback voltage to output a stable power supply voltage.

2. The power management circuit according to claim 1, characterized in that: The power management circuit also includes a second control module; The second control module is used to output a second control signal to the feedback circuit; The feedback circuit is used to adjust the load resistance of the feedback circuit according to the second control signal, and then sample the real-time power supply voltage output by the target voltage stabilization working circuit according to the corresponding load resistance to obtain a corresponding feedback voltage.

3. The power management circuit according to claim 1, characterized in that: The first control module includes a plurality of inverters and a plurality of AND gates; Each of the inverters is used to receive a binary control code; Each of the AND gates is used to generate the first control signal according to the binary control code, and then output the first control signal to the feedback circuit.

4. The power management circuit according to claim 1, characterized in that: The target voltage stabilization working circuit includes a voltage control circuit, a switch circuit and a load circuit; the voltage control circuit includes a first error amplifier, a first reference voltage source, a first comparator and a voltage controlled oscillator; The feedback circuit is used to sample the real-time power supply voltage output by the load circuit to obtain a corresponding feedback voltage; The first error amplifier is used to compare the feedback voltage with a first reference voltage generated by the first reference voltage source, and output a first error signal according to the comparison result; The first comparator is used to compare the first error signal with the ramp signal generated by the voltage controlled oscillator, and output a first pulse width modulation signal according to the comparison result; The switch circuit is used to adjust the power supply voltage according to the first pulse width modulation signal to output a corresponding output voltage; The load circuit is used to adjust the output voltage to output a stable supply voltage.

5. The power management circuit according to claim 1, characterized in that: The target voltage stabilization working circuit includes a hysteresis control circuit, a switch circuit and a load circuit; the hysteresis control circuit includes a second comparator and a second reference voltage source; When the feedback circuit is connected to the second DC-DC conversion circuit according to the first control signal: The feedback circuit is used to sample the real-time power supply voltage output by the load circuit to obtain a corresponding feedback voltage; The second comparator is used for comparing the feedback voltage with the second reference voltage generated by the second reference voltage source, and outputting a second pulse width modulation signal according to the comparison result; The switch circuit is used to adjust the power supply voltage according to the second pulse width modulation signal to output a corresponding output voltage; The load circuit is used to adjust the output voltage to output a stable supply voltage.

6. The power management circuit according to claim 4 or 5, characterized in that: The target voltage stabilization working circuit also includes an overcurrent protection module; The input end of the overcurrent protection module is electrically connected to the output end of the feedback circuit, and the output end of the zero-crossing detection module is electrically connected to the input end of the switch circuit.

7. The power management circuit according to claim 5, characterized in that: The target voltage stabilization working circuit also includes a zero-crossing detection module; The input end of the zero-crossing detection module is electrically connected to the output end of the feedback circuit, and the output end of the zero-crossing detection module is electrically connected to the input end of the switch circuit.

8. A power management chip, characterized in that: Comprising a power management circuit as claimed in any one of claims 1 to 7.

9. A control method for a power management circuit, characterized in that: The power management circuit comprises a first control module, a feedback circuit and a plurality of voltage stabilization circuits, one of the voltage stabilization circuits is a low voltage difference linear voltage stabilization circuit, and the other voltage stabilization circuits are DC-DC conversion circuits; The first control module outputs a first control signal to the feedback circuit; The feedback circuit is connected to the target voltage stabilization working circuit according to the first control signal; The feedback circuit samples the supply voltage output by the target voltage stabilization working circuit to obtain a corresponding feedback voltage, and outputs the feedback voltage to the target voltage stabilization working circuit; The target voltage stabilization working circuit adjusts the power supply voltage according to the feedback voltage to output a stable power supply voltage.

10. The method according to claim 9, characterized in that The power management circuit further includes a second control module; the method further includes: The second control module outputs a second control signal to the feedback circuit; The feedback circuit samples the supply voltage output by the target voltage stabilization working circuit to obtain a corresponding feedback voltage, including: The feedback circuit adjusts the load resistance of the feedback circuit according to the second control signal, and then samples the real-time power supply voltage output by the target voltage stabilization working circuit according to the corresponding load resistance to obtain a corresponding feedback voltage.

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