Driving circuit and chip of low dropout linear regulator

Abstract

The application discloses a driving circuit and a chip of a low-dropout linear regulator, which comprises a reference voltage generating module, a bias current generating module and a selection module. The selection module is connected with the reference voltage generating module and the bias current generating module respectively and receives a control signal. The selection module outputs a target bias current and a first reference voltage to the low-dropout linear regulator in a first time period based on the control signal, so that the low-dropout linear regulator switches from a first power consumption mode to a second power consumption mode, and then outputs a second reference voltage to the low-dropout linear regulator after the first time period to maintain the second power consumption mode. The power consumption of the first power consumption mode is less than that of the second power consumption mode, and the target bias current gradually increases to a preset value over time. The second reference voltage is established by the reference voltage generating module in the first time period. In this way, the wake-up speed of the low-dropout linear regulator is increased, and the wake-up time of the low-dropout linear regulator is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electronic circuits, in particular to a driving circuit and a chip suitable for a low dropout linear regulator. BACKGROUND

[0002] As a key component of electronic products, a chip usually has multiple power consumption modes. The chip switches among the multiple power consumption modes to meet daily needs. The switching of the power consumption modes usually requires time. The switching time of the chip power consumption mode mainly depends on the establishment speed of the power supply and the clock.

[0003] The LDO (Low Dropout Regulator) is a common chip power supply. How to shorten the switching time between the power consumption modes of the LDO is a problem to be solved. SUMMARY

[0004] To solve the above problems, the present application provides a driving circuit and a chip suitable for a low dropout linear regulator, which can effectively increase the wake-up speed of the low dropout linear regulator and reduce the wake-up time of the low dropout linear regulator.

[0005] One technical solution adopted by the present application is to provide a driving circuit suitable for a low dropout linear regulator, which comprises a reference voltage generating module, a bias current generating module and a selection module, and the selection module is connected to the reference voltage generating module and the bias current generating module. The reference voltage generating module is used to generate a first reference voltage and a second reference voltage. The accuracy of the second reference voltage is higher than that of the first reference voltage. The bias current generating module is used to generate a target bias current. The selection module is used to receive a control signal and output the target bias current and the first reference voltage to the low dropout linear regulator in a first time period based on the control signal, so as to switch the low dropout linear regulator from a first power consumption mode to a second power consumption mode, and output the second reference voltage to the low dropout linear regulator after the first time period to maintain the second power consumption mode. The power consumption of the first power consumption mode is less than that of the second power consumption mode. The target bias current gradually increases to a preset value over time. The second reference voltage is established by the reference voltage generating module within the first time period.

[0006] In an embodiment, the bias current generating module comprises a first current source and a second current source. The input end of the first current source is coupled to a working voltage end, and the output end of the first current source is coupled to the selection module. The input end of the second current source is coupled to the working voltage end, and the output end of the second current source is coupled to the selection module. The first current source is used to generate a first bias current. The second current source is used to generate a second bias current. The target bias current is equal to the sum of the first bias current and the second bias current. The accuracy of the first bias current is higher than that of the second bias current.

[0007] In one embodiment, the bias current generating module further includes: at least two auxiliary current sources, the input terminal of each auxiliary current source being coupled to the operating voltage terminal, and the output terminal of each auxiliary current source being coupled to the selection module, for generating auxiliary bias current; wherein, the target bias current is equal to the sum of the first bias current, the second bias current and the auxiliary bias current.

[0008] In one embodiment, the selection module includes: a control unit, a first switch, and a second switch. The control terminal of the first switch is coupled to the control unit, and the first terminal of the first switch is coupled to the output terminals of the first current source and the second current source, and the first terminal of the first switch is coupled to a low-dropout linear regulator. The control terminal of the second switch is coupled to the control unit, and the first terminal of the second switch is coupled to the output terminal of the auxiliary current source, and the first terminal of the second switch is coupled to the first terminal of the first switch. The control unit is used to control the first switch and the second switch to be turned on so that the bias current generating module outputs a target bias current to the low-dropout linear regulator.

[0009] In one embodiment, the bias current generation module includes: a first current source and at least two second current sources, the input terminal of the first current source being coupled to a working voltage terminal, and the output terminal of the first current source being coupled to a selection module; the input terminal of each second current source being coupled to a working voltage terminal, and the output terminal of each second current source being coupled to the selection module; wherein, the first current source is used to generate a first bias current; the second current sources are used to generate a second bias current; the accuracy of the first bias current is greater than the accuracy of the second bias current; the selection module uses the second bias current as a target bias current during the time when the first current source generates the first bias current and the reference voltage generation module generates the second reference voltage; after the first current source generates the first bias current and the reference voltage generation module generates the second reference voltage, the selection module uses the first bias current as the target bias current.

[0010] In an embodiment, the selection module comprises a control unit, a first inverter, a first switch, a third switch and a fourth switch, an input terminal of the first inverter is coupled to the control unit, a second terminal of the first switch is coupled to the low dropout linear regulator, a control terminal of the third switch is coupled to the input terminal of the first inverter, a first terminal of the third switch is coupled to an output terminal of the first current source, a second terminal of the third switch is coupled to a first terminal of the first switch, a control terminal of the fourth switch is coupled to an output terminal of the first inverter, a first terminal of the fourth switch is coupled to an output terminal of the auxiliary current source, a second terminal of the fourth switch is coupled to the first terminal of the third switch, wherein the control unit controls the third switch to be turned off, the first switch and the fourth switch to be turned on, and the second bias current to be output as the target bias current during a time period when the first current source generates the first bias current and the reference voltage generation module generates the second reference voltage, and the control unit controls the first switch and the third switch to be turned on, the fourth switch to be turned off, and the first bias current to be output as the target bias current after the first current source generates the first bias current and the reference voltage generation module generates the second reference voltage.

[0011] In an embodiment, the reference voltage generation module comprises a first reference voltage generation unit and a second reference voltage generation unit, the first reference voltage generation unit is coupled to the selection module and is configured to generate the first reference voltage, and the second reference voltage generation unit is coupled to the selection module, wherein the first reference voltage generation unit is configured to generate the first reference voltage, and the second reference voltage generation unit is configured to generate the second reference voltage during a first time period.

[0012] In an embodiment, the selection module comprises a control unit, a second inverter, a fifth switch and a sixth switch, an input terminal of the second inverter is coupled to the control unit, a control terminal of the fifth switch is coupled to an output terminal of the second inverter, a first terminal of the fifth switch is coupled to an output terminal of the first reference voltage generation unit, a second terminal of the fifth switch is coupled to the low dropout linear regulator, a control terminal of the sixth switch is coupled to the input terminal of the second inverter, a first terminal of the sixth switch is coupled to an output terminal of the second reference voltage generation unit, and a second terminal of the sixth switch is coupled to the second terminal of the fifth switch, wherein the control unit controls the fifth switch to be turned on and the sixth switch to be turned off to output the first reference voltage to the low dropout linear regulator based on a control signal during the first time period, so that the low dropout linear regulator switches from the first power consumption mode to the second power consumption mode, and the control unit controls the fifth switch to be turned off and the sixth switch to be turned on to output the second reference voltage to the low dropout linear regulator after the first time period.

[0013] In an embodiment, the first time period is greater than or equal to a setting time of the second reference voltage.

[0014] The application further provides a driving method of a low-dropout linear voltage regulator connected to a driving circuit, the driving circuit comprising a reference voltage generating module, a bias current generating module and a selection module, the selection module being connected to the reference voltage generating module and the bias current generating module respectively; the reference voltage generating module being configured to generate a first reference voltage and a second reference voltage; the bias current generating module being configured to generate a target bias current; the second reference voltage having a higher precision than the first reference voltage; the driving method comprising:

[0015] sending a control signal to the selection module to control the selection module to output the target bias current and the first reference voltage to the low-dropout linear voltage regulator in a first time period, so as to switch the low-dropout linear voltage regulator from a first power consumption mode to a second power consumption mode;

[0016] after the first time period, controlling the selection module to output the second reference voltage to the low-dropout linear voltage regulator to maintain the second power consumption mode; wherein the power consumption of the first power consumption mode is less than that of the second power consumption mode, and the target bias current gradually increases to a preset value over time; and the second reference voltage is established by the reference voltage generating module in the first time period.

[0017] The application further provides a chip comprising a low-dropout linear voltage regulator and a driving module connected to the low-dropout linear voltage regulator, the driving module comprising the driving circuit as described above.

[0018] The low-dropout linear regulator driving circuit provided by the application comprises a reference voltage generating module, a bias current generating module and a selection module, the selection module is connected with the reference voltage generating module and the bias current generating module respectively; the reference voltage generating module is used to generate a first reference voltage and a second reference voltage; the precision of the second reference voltage is higher than that of the first reference voltage; the bias current generating module is used to generate a target bias current; the selection module is used to receive a control signal and output the target bias current and the first reference voltage to the low-dropout linear regulator in a first time period based on the control signal, so that the low-dropout linear regulator is switched from a first power consumption mode to a second power consumption mode, and the second reference voltage is output to the low-dropout linear regulator after the first time period to maintain the second power consumption mode; the power consumption of the first power consumption mode is less than that of the second power consumption mode, and the target bias current gradually increases to a preset value over time; the second reference voltage is established by the reference voltage generating module in the first time period. In the above manner, the bias current generating module is improved, the low-precision first reference voltage is used to support the switching of the low-dropout linear regulator from the first power consumption mode to the second power consumption mode in the first time period, the switching of the power consumption mode is performed while the high-precision second reference voltage is established, the target bias current gradually increases to the preset value over time, the switching of the power consumption mode is not required to wait until the second reference voltage is established and the bias current corresponding to the second power consumption mode is established, and the second reference voltage is output to the low-dropout linear regulator after the first time period to maintain the second power consumption mode, so that the switching speed of the second power consumption mode of the low-dropout linear regulator is accelerated, the overall switching time of the second power consumption mode of the low-dropout linear regulator is reduced, and the stability of the output voltage of the low-dropout linear regulator during the switching of the two power consumption modes is improved. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without any creative effort. Among them:

[0020] Figure 1 FIG. 1 is a structural schematic diagram of a first embodiment of the low-dropout linear regulator driving circuit provided by the application;

[0021] Figure 2 FIG. 2 is a structural schematic diagram of a second embodiment of the low-dropout linear regulator driving circuit provided by the application;

[0022] Figure 3 FIG. 3 is a structural schematic diagram of a third embodiment of the low-dropout linear regulator driving circuit provided by the application;

[0023] Figure 4 FIG. 4 is a structural schematic diagram of a fourth embodiment of a driving circuit of a low-dropout linear regulator provided in the present application;

[0024] Figure 5 FIG. 5 is a structural schematic diagram of a fifth embodiment of a driving circuit of a low-dropout linear regulator provided in the present application;

[0025] Figure 6 FIG. 6 is a structural schematic diagram of an embodiment of a low-dropout linear regulator provided in the present application;

[0026] Figure 7 FIG. 7 is a timing schematic diagram of a driving circuit of a low-dropout linear regulator provided in the present application;

[0027] Figure 8 FIG. 8 is a flow schematic diagram of a driving method of a low-dropout linear regulator provided in the present application;

[0028] Figure 9 FIG. 9 is a structural schematic diagram of an embodiment of a chip provided in the present application. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the drawings in the embodiments of the present application. It can be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application. In addition, it should be noted that, for the convenience of description, only the parts related to the present application are shown in the drawings, and not all the structures. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0030] The terms "first", "second", and the like in the present application are used to distinguish different objects, and are not used to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to the process, method, product or device.

[0031] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily mutually exclusive of other embodiments. It is explicitly and implicitly understood that the embodiments described herein can be combined with other embodiments.

[0032] Reference is made toFigure 1 , Figure 1 is a structural schematic diagram of a first embodiment of a driving circuit of a low-dropout linear regulator provided by the present application. The driving circuit 100 comprises a reference voltage generation module 10, a bias current generation module 20, and a selection module 30, and the selection module 30 is connected to the reference voltage generation module 10 and the bias current generation module 20 respectively.

[0033] The reference voltage generation module 10 is configured to generate a first reference voltage LPBG_VREF and a second reference voltage HPBG_VREF, and the accuracy of the second reference voltage HPBG_VREF is higher than that of the first reference voltage LPBG_VREF.

[0034] The bias current generation module 20 is configured to generate a target bias current IB_LDO_HP.

[0035] The selection module 30 is configured to receive a control signal HPLDO_EN, and output the target bias current IB_LDO_HP and the first reference voltage LPBG_VREF to the low-dropout linear regulator in a first time period based on the control signal HPLDO_EN, so as to switch the low-dropout linear regulator from a first power consumption mode to a second power consumption mode, and output the second reference voltage HPBG_VREF to the low-dropout linear regulator after the first time period to maintain the second power consumption mode; the power consumption of the first power consumption mode is less than that of the second power consumption mode, and the target bias current IB_LDO_HP gradually increases to a preset value over time; and the second reference voltage HPBG_VREF is established by the reference voltage generation module 10 in the first time period.

[0036] In some embodiments, the time of the first time period is greater than or equal to the establishment time of the second reference voltage HPBG_VREF.

[0037] Exemplarily, the working modes of the low-dropout linear regulator include a low-power consumption mode and a normal mode. In the low-power consumption mode, the driving capability of the low-dropout linear regulator is weak, and mainly supplies power to a small part of modules in the low-power consumption mode. In the normal mode, the driving capability of the low-dropout linear regulator is strong, and can supply power to all functional modules to work at the same time. In an embodiment, the first power consumption mode corresponds to the low-power consumption mode, and the second power consumption mode corresponds to the normal mode.

[0038] Exemplarily, in the first power consumption mode, the bias current of the low-dropout linear regulator is mainly provided by a current source with a fixed output current (not shown in the figure), and at the same time, the target bias current IB_LDO_HP gradually increases to a preset value over time, so as to improve the accuracy of the output voltage and current of the low-dropout linear regulator.

[0039] Exemplarily, the current demand of the load can change with the change of the working state. In order to ensure that the low-dropout linear regulator can provide stable output voltage and current while reducing unnecessary power consumption, the low-dropout linear regulator needs to switch between the low-power mode and the normal mode. When the load current demand is low, the low-dropout linear regulator can enter the low-power mode to reduce power consumption, and when the load current demand is high, the low-dropout linear regulator can be woken up from the low-power mode and work in the normal mode to provide high-precision output voltage and current.

[0040] Exemplarily, the driving circuit 100 of the low-dropout linear regulator is used to generate a reference voltage and a bias current. The reference voltage is used to provide a stable voltage reference for the low-dropout linear regulator, which is used to compare with the feedback voltage to control the stability of the output voltage. The bias current is the quiescent current of the low-dropout linear regulator, which is used to maintain stable output voltage and current. In the low-power mode, the low-dropout linear regulator has low output accuracy requirements, and a low-precision first reference voltage LPBG_VREF is used.

[0041] In the normal mode, the low-dropout linear regulator has high output accuracy requirements, and high-precision reference voltage and high-precision bias current are required. A high-precision second reference voltage HPBG_VREF is used to ensure that the output voltage can be maintained stable when the load changes. Similarly, in the low-power mode, the bias current has low precision, and in the normal mode, the bias current has high precision.

[0042] Exemplarily, when the low-dropout linear regulator is woken up, the reference voltage is the first reference voltage LPBG_VREF; after the second reference voltage HPBG_VREF is established, the reference voltage of the low-dropout linear regulator is switched to the second reference voltage HPBG_VREF, and the target bias current IB_LDO_HP is gradually increased to a preset value.

[0043] In this embodiment, during the period of switching from the first power consumption mode to the second power consumption mode, the reference voltage and the bias current always exist, which can ensure that there is no need to wait for the establishment of the bias current during mode switching, and the wake-up time of the low-dropout linear regulator is effectively reduced.

[0044] Referring to Figure 2 and Figure 3 , Figure 2 and Figure 3 are the structural schematic diagrams of the second and third embodiments of the driving circuit of the low-dropout linear regulator provided by the present application. The driving circuit 100 includes a reference voltage generating module 10, a bias current generating module 20, and a selection module 30, and the selection module 30 is connected to the reference voltage generating module 10 and the bias current generating module 20, respectively.

[0045] The reference voltage generation module 10 is configured to generate a first reference voltage LPBG_VREF and a second reference voltage HPBG_VREF, and the precision of the second reference voltage HPBG_VREF is higher than that of the first reference voltage LPBG_VREF.

[0046] The bias current generation module 20 is configured to generate a target bias current IB_LDO_HP.

[0047] The selection module 30 is configured to receive a control signal HPLDO_EN, and output the target bias current IB_LDO_HP and the first reference voltage LPBG_VREF to the low-dropout linear regulator in a first time period based on the control signal HPLDO_EN, so that the low-dropout linear regulator switches from a first power consumption mode to a second power consumption mode, and output the second reference voltage HPBG_VREF to the low-dropout linear regulator after the first time period to maintain the second power consumption mode; the power consumption of the first power consumption mode is less than that of the second power consumption mode, and the target bias current IB_LDO_HP gradually increases to a preset value over time; and the second reference voltage HPBG_VREF is established by the reference voltage generation module 10 in the first time period.

[0048] In some optional embodiments, as shown in Figure 2 The bias current generation module 20 includes a first current source S1 and a second current source S2, an input end of the first current source S1 is coupled to the working voltage end, and an output end of the first current source S1 is coupled to the selection module 30; an input end of the second current source S2 is coupled to the working voltage end, and an output end of the second current source S2 is coupled to the selection module 30; the first current source S1 is configured to generate a first bias current HPBG_IBIAS; the second current source S2 is configured to generate a second bias current LPBG_IBIAS; the target bias current IB_LDO_HP is equal to the sum of the first bias current HPBG_IBIAS and the second bias current LPBG_IBIAS, and the precision of the first bias current HPBG_IBIAS is higher than that of the second bias current LPBG_IBIAS.

[0049] Exemplarily, the current source is used to provide a bias current to an error amplifier in a low-dropout linear regulator, performance of the error amplifier is affected by accuracy of the bias current, the accuracy of the bias current affects parameters such as gain of the error amplifier, thereby affecting an output of the low-dropout linear regulator. In a first power consumption mode, driving capability of the low-dropout linear regulator is weak, and the accuracy of the bias current is low, in a second power consumption mode, the accuracy of the bias current is high. The target bias current IB_LDO_HP is equal to a sum of a first bias current HPBG_IBIAS and a second bias current LPBG_IBIAS, during wake-up of the low-dropout linear regulator, the first bias current HPBG_IBIAS gradually increases, so that the target bias current IB_LDO_HP gradually increases to a preset value over time.

[0050] Wherein, a proportion of the first bias current HPBG_IBIAS and the second bias current LPBG_IBIAS in the target bias current IB_LDO_HP can be selected according to requirements of the error amplifier on current accuracy and wake-up speed, the smaller the proportion of the second bias current LPBG_IBIAS, the higher the accuracy of the target bias current IB_LDO_HP, the higher the proportion of the second bias current LPBG_IBIAS, the faster the wake-up speed of the error amplifier.

[0051] In some embodiments, the selection module 30 comprises a control unit 31 and a first switch SW1, a control end of the first switch SW1 is coupled to the control unit 31, a first end of the first switch SW1 is coupled to output ends of the first current source S1 and the second current source S2, and the first end of the first switch SW1 is coupled to the low-dropout linear regulator. Wherein, the control unit 31 is configured to control the first switch SW1 to be turned on, so that the bias current generation module 20 outputs the target bias current IB_LDO_HP to the low-dropout linear regulator.

[0052] Exemplarily, the control unit 31 can be an analog switch controller or the like, the control unit 31 receives a control signal HPLDO_EN, and controls turning on and turning off of the first switch SW1 according to the control signal HPLDO_EN. When the first switch SW1 is turned on, the target bias current IB_LDO_HP provided by the first current source S1 and the second current source is output to the low-dropout linear regulator.

[0053] In some optional embodiments, as shown in Figure 3 , as shown in Figure 3 , a driving circuit 100 of the low-dropout linear regulator and Figure 2The driving circuit 100 of the low-dropout linear regulator shown mainly differs in that the related descriptions of the auxiliary current source S3 and the second switch SW2 are added, thus, the auxiliary current source S3 and the second switch SW2 are mainly described below, and the other components in the driving circuit 100 of the low-dropout linear regulator can be referred to the related descriptions of the first switch SW1 in Figure 2 the related descriptions of the embodiments shown, for example Figure 3 the first switch SW1 in Figure 2 the related descriptions of the first switch SW1 in

[0054] In some embodiments, the bias current generation module 20 further comprises: at least two auxiliary current sources S3, an input end of each auxiliary current source S3 is coupled to the working voltage end, and an output end of each auxiliary current source S3 is coupled to the selection module 30, for generating an auxiliary bias current LPBG_IBIAS1N; wherein the target bias current IB_LDO_HP is equal to the sum of the first bias current HPBG_IBIAS, the second bias current LPBG_IBIAS, and the auxiliary bias current LPBG_IBIAS1N.

[0055] Exemplarily, the auxiliary current source S3 provides additional bias current during the wake-up of the low-dropout linear regulator, which helps to accelerate the establishment speed of the error amplifier, so that the low-dropout linear regulator quickly reaches a stable working state, reduces the wake-up time, and at the same time increases the driving capability of the low-dropout linear regulator in the first power consumption mode. Wherein, the number of auxiliary current sources S3 can be increased according to the requirements of the circuit.

[0056] In some embodiments, the selection module 30 further comprises: a second switch SW2, a control end of the second switch SW2 is coupled to the control unit 31, a first end of the second switch SW2 is coupled to the output end of the auxiliary current source S3, and the first end of the second switch SW2 is coupled to the first end of the first switch SW1; wherein the control unit 31 is configured to control the first switch SW1 and the second switch SW2 to be turned on, so that the bias current generation module 20 outputs the target bias current IB_LDO_HP to the low-dropout linear regulator.

[0057] Exemplarily, the first switch SW1 and the second switch SW2 are turned on at the same time, at the moment of turning on, the first bias current HPBG_IBIAS output by the first current source S1 has not been established completely, and the target bias current IB_LDO_HP is mainly composed of the second bias current LPBG_IBIAS output by the second current source S2 and the auxiliary bias current LPBG_IBIAS1N output by the auxiliary current source S3. After a period of time, the second switch SW2 is turned off to reduce the power consumption of the low-dropout linear regulator.

[0058] In the embodiment, by reasonably designing the number of current sources and auxiliary current source S3 of the bias current generation module 20 and the switch delay-off strategy, the stability and output accuracy of the low dropout linear regulator can be significantly improved, the wake-up speed of the low dropout linear regulator can be improved, the power consumption can be saved, and the needs of various application scenarios can be met.

[0059] Referring to Figure 4 , Figure 4 is a structural schematic diagram of a fourth embodiment of a driving circuit of a low dropout linear regulator provided by the present application. The driving circuit 100 includes a reference voltage generation module 10, a bias current generation module 20, and a selection module 30, and the selection module 30 is connected to the reference voltage generation module 10 and the bias current generation module 20, respectively.

[0060] The reference voltage generation module 10 is configured to generate a first reference voltage LPBG_VREF and a second reference voltage HPBG_VREF, and the accuracy of the second reference voltage HPBG_VREF is greater than the accuracy of the first reference voltage LPBG_VREF.

[0061] The bias current generation module 20 is configured to generate a target bias current IB_LDO_HP.

[0062] The selection module 30 is configured to receive a control signal HPLDO_EN, and based on the control signal HPLDO_EN, output the target bias current IB_LDO_HP and the first reference voltage LPBG_VREF to the low dropout linear regulator in a first time period, so as to make the low dropout linear regulator switch from a first power consumption mode to a second power consumption mode, and output the second reference voltage HPBG_VREF to the low dropout linear regulator after the first time period to maintain the second power consumption mode; wherein the power consumption of the first power consumption mode is less than the power consumption of the second power consumption mode, and the target bias current IB_LDO_HP gradually increases to a preset value over time; the second reference voltage HPBG_VREF is established by the reference voltage generation module 10 in the first time period.

[0063] In some embodiments, the bias current generation module 20 comprises: a first current source S1 and at least two second current sources S2, an input terminal of the first current source S1 is coupled to the working voltage terminal, and an output terminal of the first current source S1 is coupled to the selection module 30; an input terminal of each second current source S2 is coupled to the working voltage terminal, and an output terminal of each second current source S2 is coupled to the selection module 30; wherein the first current source S1 is configured to generate a first bias current HPBG_IBIAS; the second current source S2 is configured to generate a second bias current LPBG_IBIAS; the precision of the first bias current HPBG_IBIAS is greater than the precision of the second bias current LPBG_IBIAS; the selection module 30 is configured to use the second bias current LPBG_IBIAS as a target bias current IB_LDO_HP during a time period when the first current source S1 generates the first bias current HPBG_IBIAS and the reference voltage generation module 10 generates a second reference voltage HPBG_VREF; and the selection module 30 is configured to use the first bias current HPBG_IBIAS as the target bias current IB_LDO_HP after the first current source S1 generates the first bias current HPBG_IBIAS and the reference voltage generation module 10 generates the second reference voltage HPBG_VREF. The number of second current sources S2 can be increased according to the requirements of the circuit.

[0064] In some embodiments, the selection module 30 comprises: a control unit 31, a first inverter A1, a first switch SW1, a third switch SW3, and a fourth switch SW4. An input terminal of the first inverter A1 is coupled to the control unit 31; a second terminal of the first switch SW1 is coupled to the low dropout linear regulator; a control terminal of the third switch SW3 is coupled to the input terminal of the first inverter A1, a first terminal of the third switch SW3 is coupled to the output terminal of the first current source S1, and a second terminal of the third switch SW3 is coupled to the first terminal of the first switch SW1; a control terminal of the fourth switch SW4 is coupled to an output terminal of the first inverter A1, a first terminal of the fourth switch SW4 is coupled to an output terminal of the auxiliary current source S3, and a second terminal of the fourth switch SW4 is coupled to the first terminal of the third switch SW3; wherein the control unit 31 is configured to control the third switch SW3 to be turned off, the first switch SW1 and the fourth switch SW4 to be turned on, and the second bias current LPBG_IBIAS to be used as the target bias current IB_LDO_HP during a time period when the first current source S1 generates the first bias current HPBG_IBIAS and the reference voltage generation module 10 generates the second reference voltage HPBG_VREF; and the control unit 31 is configured to control the first switch SW1 and the third switch SW3 to be turned on, and the fourth switch SW4 to be turned off, after the first current source S1 generates the first bias current HPBG_IBIAS and the reference voltage generation module 10 generates the second reference voltage HPBG_VREF, so that the first bias current HPBG_IBIAS is used as the target bias current IB_LDO_HP.

[0065] Exemplarily, the second bias current LPBG_IBIAS has a lower precision, so that the precision of the target bias current IB_LDO_HP is affected, as shown in Figure 4 As shown in the first power consumption mode and the second power consumption mode, the first switch SW1 is always in the on state, and during the time when the first current source S1 generates the first bias current HPBG_IBIAS and the reference voltage generation module 10 generates the second reference voltage HPBG_VREF, the fourth switch SW4 is controlled to be on, so that the second current source S2 is connected to the loop of the low-dropout linear regulator, and the target bias current IB_LDO_HP is only provided by the second current source S2. The number of the second current source S2 can be increased according to the requirement of the circuit, so as to improve the wake-up speed of the low-dropout linear regulator; after the first current source S1 generates the first bias current HPBG_IBIAS and the reference voltage generation module 10 generates the second reference voltage HPBG_VREF, the fourth switch SW4 is controlled to be off, and the third switch SW3 is controlled to be on, so that the first current source S1 is connected to the loop of the low-dropout linear regulator, and the target bias current IB_LDO_HP is only provided by the first current source S1, thereby improving the output precision of the low-dropout linear regulator.

[0066] Referring to Figure 5 , Figure 5 is a structural schematic diagram of a fifth embodiment of the driving circuit of the low-dropout linear regulator provided by the present application. The driving circuit 100 includes a reference voltage generation module 10, a bias current generation module 20 and a selection module 30, and the selection module 30 is connected to the reference voltage generation module 10 and the bias current generation module 20 respectively.

[0067] The reference voltage generation module 10 is configured to generate a first reference voltage LPBG_VREF and a second reference voltage HPBG_VREF, and the precision of the second reference voltage HPBG_VREF is higher than that of the first reference voltage LPBG_VREF.

[0068] The bias current generation module 20 is configured to generate a target bias current IB_LDO_HP.

[0069] The selection module 30 is configured to receive the control signal HPLDO_EN, and output the target bias current IB_LDO_HP and the first reference voltage LPBG_VREF to the low-dropout linear regulator in a first time period based on the control signal HPLDO_EN, so as to make the low-dropout linear regulator switch from a first power consumption mode to a second power consumption mode, and output the second reference voltage HPBG_VREF to the low-dropout linear regulator after the first time period to maintain the second power consumption mode; wherein the power consumption of the first power consumption mode is less than the power consumption of the second power consumption mode, and the target bias current IB_LDO_HP gradually increases to a preset value over time; the second reference voltage HPBG_VREF is established by the reference voltage generation module 10 in the first time period.

[0070] In some embodiments, the reference voltage generation module 10 comprises: a first reference voltage generation unit 11 and a second reference voltage generation unit 12, the first reference voltage generation unit 11 is coupled to the selection module 30; the second reference voltage generation unit 12 is coupled to the selection module 30; wherein the first reference voltage generation unit 11 is configured to generate the first reference voltage LPBG_VREF; and the second reference voltage generation unit 12 is configured to generate the second reference voltage HPBG_VREF in the first time period.

[0071] In some embodiments, the selection module 30 comprises: a control unit 31, a second inverter A2, a fifth switch SW5, and a sixth switch SW6. The input end of the second inverter A2 is coupled to the control unit 31; the control end of the fifth switch SW5 is coupled to the output end of the second inverter A2, the first end of the fifth switch SW5 is coupled to the output end of the first reference voltage generation unit 11, and the second end of the fifth switch SW5 is coupled to the low-dropout linear regulator; the control end of the sixth switch SW6 is coupled to the input end of the second inverter A2, the first end of the sixth switch SW6 is coupled to the output end of the second reference voltage generation unit 12, and the second end of the sixth switch SW6 is coupled to the second end of the fifth switch SW5; wherein the control unit 31 controls the fifth switch SW5 to be turned on, the sixth switch SW6 to be turned off, and the first reference voltage LPBG_VREF to be output to the low-dropout linear regulator in the first time period based on the control signal HPLDO_EN, so as to make the low-dropout linear regulator switch from the first power consumption mode to the second power consumption mode, and controls the fifth switch SW5 to be turned off, the sixth switch SW6 to be turned on, and the second reference voltage HPBG_VREF to be output to the low-dropout linear regulator after the first time period.

[0072] Exemplarily, the second inverter A2 is configured to invert the level of the output signal of the control unit 31, i.e., the sixth switch SW6 is turned off when the fifth switch SW5 is turned on, and the sixth switch SW6 is turned on when the fifth switch SW5 is turned off. When the low-dropout linear regulator enters the first power consumption mode, the fifth switch SW5 is turned on and the sixth switch SW6 is turned off, so that the path between the first reference voltage generating unit 11 and the low-dropout linear regulator is turned on, and the first reference voltage LPBG_VREF is provided for the low-dropout linear regulator; when switching to the second power consumption mode, the fifth switch SW5 is turned off and the sixth switch SW6 is turned on, so that the path between the second reference voltage generating unit 12 and the low-dropout linear regulator is turned on, and the second reference voltage HPBG_VREF is provided for the low-dropout linear regulator.

[0073] Referring to Figure 6 , Figure 6 is a structural schematic diagram of an embodiment of the low-dropout linear regulator provided in the present application.

[0074] The low-dropout linear regulator 600 is connected to a driving circuit 100, which includes a reference voltage generating module 10, a bias current generating module 20, and a selection module 30 connected to the reference voltage generating module 10 and the bias current generating module 20, respectively.

[0075] The reference voltage generating module 10 is configured to generate a first reference voltage LPBG_VREF and a second reference voltage HPBG_VREF, and the accuracy of the second reference voltage HPBG_VREF is greater than that of the first reference voltage LPBG_VREF.

[0076] The bias current generating module 20 is configured to generate a target bias current IB_LDO_HP.

[0077] The selection module 30 is configured to receive a control signal HPLDO_EN and output the target bias current IB_LDO_HP and the first reference voltage LPBG_VREF to the low-dropout linear regulator in a first time period based on the control signal HPLDO_EN, so as to switch the low-dropout linear regulator from the first power consumption mode to the second power consumption mode, and output the second reference voltage HPBG_VREF to the low-dropout linear regulator after the first time period to maintain the second power consumption mode; the power consumption of the first power consumption mode is less than that of the second power consumption mode, and the target bias current IB_LDO_HP gradually increases to a preset value over time; the second reference voltage HPBG_VREF is established by the reference voltage generating module 10 in the first time period.

[0078] The low dropout linear voltage regulator 600 comprises a first error amplifier GMHP, a second error amplifier GMLP, a seventh switch SW7, an eighth switch SW8, a transistor M1, a first resistor R1 and a second resistor R2. The first error amplifier GMHP is connected to the selection module 30 and the second error amplifier GMLP respectively, and is connected to the control end of the transistor M1 through the seventh switch SW7; the second error amplifier GMLP is connected to the selection module 30, the fourth current source S4, the control end of the transistor M1 and the load respectively, and is grounded through the first resistor R1 and the second resistor R2; the first end of the first resistor R1 is connected to the second end of the transistor M1 and the first end of the second resistor R2; the second end of the first resistor R1 is grounded through the eighth switch SW8; and the second end of the second resistor R2 is grounded.

[0079] In the working process of the low dropout linear voltage regulator 600, the second error amplifier GMLP receives the bias current LPBG_IBIAS2 output by the fourth current source S4 and the reference voltage signal output by the reference voltage generation module 10, and the first error amplifier GMHP receives the reference voltage signal output by the reference voltage generation module 10 and the target bias current IB_LDO_HP generated by the bias current generation module 20. In the first power consumption mode, the first error amplifier GMHP, the seventh switch SW7 and the eighth switch SW8 are turned off, and the output of the low dropout linear voltage regulator 600 is mainly composed of the voltage output by the second error amplifier GMLP under the action of the bias current LPBG_IBIAS2 and the first reference voltage LPBG_VREF; in the second power consumption mode, the first error amplifier GMHP, the seventh switch SW7 and the eighth switch SW8 are turned on, and the output of the low dropout linear voltage regulator 600 is mainly composed of the voltage output by the first error amplifier GMHP under the action of the target bias current IB_LDO_HP and the second reference voltage HPBG_VREF, and at the same time, the second error amplifier GMLP also continuously works.

[0080] Referring to Figure 7 , Figure 7 is a timing diagram of the driving circuit of the low dropout linear voltage regulator provided by the present application.

[0081] The low dropout linear voltage regulator can be Figure 6 The driving circuit is the driving circuit 100 described above, and will not be described here again.

[0082] Before the wake-up, the bias current of the low-dropout linear regulator is provided by the bias current LPBG_IBIAS2 of the second error amplifier GMLP, the reference voltage is the first reference voltage LPBG_VREF, the target bias current IB_LDO_HP is 0, the first error amplifier GMHP is in the off state, and the output of the low-dropout linear regulator is mainly provided by the second error amplifier GMLP.

[0083] When starting the wake-up, the control signal HPLDO_EN is pulled high to turn on the first error amplifier GMHP, at this time, the first reference voltage LPBG_VREF and the second bias current LPBG_IBIAS remain high, so that the output LDO_OUT of the low-dropout linear regulator also remains high; when switching to the second power consumption mode, the second reference voltage HPBG_VREF and the first bias current HPBG_IBIAS are established, and the target bias current IB_LDO_HP increases with the increase of the first bias current HPBG_IBIAS, so that the output LDO_OUT of the low-dropout linear regulator always remains high. Wherein, t1 represents the delay time of the control signal HPLDO_EN, t2 represents the establishment time of the second reference voltage HPBG_VREF, in order to ensure that the second reference voltage HPBG_VREF is completely established before switching the reference voltage, so the t1 time needs to be greater than t2.

[0084] In the above manner, the low-dropout linear regulator always maintains a stable output when waking up, and the wake-up time can be considered as 0us.

[0085] Referring to Figure 8 , Figure 8 is a flowchart of the driving method of the low-dropout linear regulator provided by the present application, the low-dropout linear regulator is connected to a driving circuit, the driving circuit includes a reference voltage generating module, a bias current generating module and a selection module, the selection module is connected to the reference voltage generating module and the bias current generating module respectively; the reference voltage generating module is used to generate a first reference voltage and a second reference voltage; the bias current generating module is used to generate a target bias current; the accuracy of the second reference voltage is greater than the accuracy of the first reference voltage, and the driving method includes:

[0086] Step S81: send a control signal to the selection module, control the selection module to output the target bias current and the first reference voltage to the low-dropout linear regulator in a first time period, so as to switch the low-dropout linear regulator from the first power consumption mode to the second power consumption mode.

[0087] Step S82: After the first time period, the control selection module outputs a second reference voltage to the low-dropout linear regulator to maintain the second power consumption mode; wherein the power consumption of the first power consumption mode is less than the power consumption of the second power consumption mode, and the target bias current gradually increases to a preset value over time; the second reference voltage is established by the reference voltage generation module within the first time period.

[0088] Referring to Figure 9 , Figure 9 is a structural schematic diagram of an embodiment of a chip provided in the present application. The chip 1000 includes a low-dropout linear regulator 200 and a driving module 300, the driving module 300 being connected to the low-dropout linear regulator 100, and the driving module 300 including the driving circuit 100 as described above.

[0089] In several embodiments provided in the present application, it should be understood that the disclosed methods and devices can be implemented in other manners. For example, the above-described device embodiments are merely schematic, and the division of the modules or units is merely a logical function division, and there can be another division manner in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0090] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., can be located in one place, or can be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purposes of the embodiments.

[0091] In addition, each functional unit in the embodiments of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be implemented in the form of hardware, or in the form of a software functional unit.

[0092] The above description is merely an embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation based on the content of the specification and drawings, or direct or indirect application in other related technical fields, is also included in the patent protection scope of the present application.

Claims

1. A drive circuit suitable for use in a low-dropout linear regulator, characterized by, The driving circuit comprises a reference voltage generating module, a bias current generating module and a selection module, and the selection module is connected to the reference voltage generating module and the bias current generating module respectively. The reference voltage generating module is configured to generate a first reference voltage and a second reference voltage, and the second reference voltage has a higher precision than the first reference voltage. The bias current generating module is configured to generate a target bias current. The selection module is configured to receive a control signal and output the target bias current and the first reference voltage to the low-dropout linear regulator in a first time period based on the control signal, so as to make the low-dropout linear regulator switch from a first power consumption mode to a second power consumption mode, and output the second reference voltage to the low-dropout linear regulator after the first time period to maintain the second power consumption mode; the first power consumption mode has a lower power consumption than the second power consumption mode, the target bias current gradually increases to a preset value over time, and the second reference voltage is established by the reference voltage generating module in the first time period.

2. The drive circuit according to claim 1, characterized by The bias current generating module comprises a first current source and a second current source, the input end of the first current source is coupled to a working voltage end, and the output end of the first current source is coupled to the selection module; the input end of the second current source is coupled to the working voltage end, and the output end of the second current source is coupled to the selection module. The first current source is configured to generate a first bias current. The second current source is configured to generate a second bias current. The target bias current is equal to the sum of the first bias current and the second bias current, and the first bias current has a higher precision than the second bias current.

3. The drive circuit according to claim 2, characterized in that, The bias current generating module further comprises: At least two auxiliary current sources, the input end of each auxiliary current source is coupled to the working voltage end, the output end of each auxiliary current source is coupled to the selection module, and each auxiliary current source is configured to generate an auxiliary bias current; and the target bias current is equal to the sum of the first bias current, the second bias current and the auxiliary bias current.

4. The drive circuit according to claim 3, characterized in that, The selection module comprises a control unit, a first switch and a second switch, the control end of the first switch is coupled to the control unit, the first end of the first switch is coupled to the output end of the first current source and the second current source, and the first end of the first switch is coupled to the low-dropout linear regulator; the control end of the second switch is coupled to the control unit, the first end of the second switch is coupled to the output end of the auxiliary current source, and the first end of the second switch is coupled to the first end of the first switch. The control unit is configured to control the first switch and the second switch to be turned on, so that the bias current generating module outputs the target bias current to the low-dropout linear regulator.

5. The drive circuit according to claim 1, characterized by The bias current generation module comprises: a first current source and at least two second current sources, an input end of the first current source is coupled to a working voltage end, and an output end of the first current source is coupled to the selection module; an input end of each of the second current sources is coupled to the working voltage end, and an output end of each of the second current sources is coupled to the selection module; The first current source is configured to generate a first bias current, and the second current source is configured to generate a second bias current; the precision of the first bias current is greater than the precision of the second bias current; The selection module uses the second bias current as the target bias current during a time period when the first current source generates the first bias current and the reference voltage generation module generates the second reference voltage; The selection module uses the first bias current as the target bias current after the first current source generates the first bias current and the reference voltage generation module generates the second reference voltage.

6. The drive circuit according to claim 5, characterized in that, The selection module comprises: a control unit, a first inverter, a first switch, a third switch, and a fourth switch, an input end of the first inverter is coupled to the control unit; a second end of the first switch is coupled to the low-dropout linear voltage regulator; a control end of the third switch is coupled to the input end of the first inverter, a first end of the third switch is coupled to the output end of the first current source, and a second end of the third switch is coupled to a first end of the first switch; a control end of the fourth switch is coupled to an output end of the first inverter, a first end of the fourth switch is coupled to an output end of the second current source, and a second end of the fourth switch is coupled to the second end of the third switch; The control unit controls the third switch to be turned off, the first switch and the fourth switch to be turned on, and the second bias current to be used as the target bias current during a time period when the first current source generates the first bias current and the reference voltage generation module generates the second reference voltage; The control unit controls the first switch and the third switch to be turned on and the fourth switch to be turned off after the first current source generates the first bias current and the reference voltage generation module generates the second reference voltage, and uses the first bias current as the target bias current.

7. The drive circuit of claim 1, wherein The reference voltage generation module comprises: a first reference voltage generation unit and a second reference voltage generation unit, the first reference voltage generation unit is coupled to the selection module, and the second reference voltage generation unit is coupled to the selection module; The first reference voltage generation unit is configured to generate the first reference voltage, and the second reference voltage generation unit is configured to generate the second reference voltage during the first time period; and / or The second reference voltage generation unit is configured to generate the second reference voltage during the second time period. The selection module comprises a control unit, a second inverter, a fifth switch and a sixth switch, an input end of the second inverter is coupled to the control unit, a control end of the fifth switch is coupled to an output end of the second inverter, a first end of the fifth switch is coupled to an output end of the first reference voltage generating unit, and a second end of the fifth switch is coupled to the low-dropout linear regulator, a control end of the sixth switch is coupled to the input end of the second inverter, a first end of the sixth switch is coupled to an output end of the second reference voltage generating unit, and a second end of the sixth switch is coupled to the second end of the fifth switch. The control unit controls the fifth switch to be turned on and the sixth switch to be turned off based on the control signal in the first time period, and outputs the first reference voltage to the low-dropout linear regulator, so as to make the low-dropout linear regulator switch from the first power consumption mode to the second power consumption mode, and controls the fifth switch to be turned off and the sixth switch to be turned on after the first time period, and outputs the second reference voltage to the low-dropout linear regulator.

8. The drive circuit according to any one of claims 1 to 7, characterized by The time of the first time period is greater than or equal to the setting time of the second reference voltage.

9. A driving method of a low dropout linear regulator, characterized by, The low-dropout linear regulator is connected to a driving circuit, the driving circuit comprises a reference voltage generating module, a bias current generating module and a selection module, the selection module is connected to the reference voltage generating module and the bias current generating module respectively, the reference voltage generating module is used to generate a first reference voltage and a second reference voltage, the bias current generating module is used to generate a target bias current, the precision of the second reference voltage is greater than the precision of the first reference voltage, and the driving method comprises: sending a control signal to the selection module, and controlling the selection module to output the target bias current and the first reference voltage to the low-dropout linear regulator in a first time period, so as to make the low-dropout linear regulator switch from the first power consumption mode to the second power consumption mode; controlling the selection module to output the second reference voltage to the low-dropout linear regulator after the first time period, so as to maintain the second power consumption mode; wherein the power consumption of the first power consumption mode is less than the power consumption of the second power consumption mode, the target bias current gradually increases to a preset value over time, and the second reference voltage is set by the reference voltage generating module in the first time period.

10. A chip, characterized by The chip comprises: a low-dropout linear regulator; a driving module connected to the low-dropout linear regulator, the driving module comprises the driving circuit according to any one of claims 1 to 8.

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