Drive circuit and chip of low dropout regulator

Abstract

The invention discloses a driving circuit and a chip of a low dropout linear regulator, the driving circuit comprises a reference voltage generation module, a bias current generation module and a selection module, the selection module is respectively connected with the reference voltage generation module and the bias current generation module and receives a control signal, and the selection module is connected with the reference voltage generation module and the bias current generation module. 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 is switched from a first power consumption mode to a second power consumption mode, and outputs a second reference voltage to the low dropout linear regulator after the first time period; maintaining the second power consumption mode; wherein the power consumption of the first power consumption mode is smaller than that of the second power consumption mode, and the target bias current is gradually increased to a preset value along with time; the second reference voltage is established by the reference voltage generation module within a first time period. By means of the mode, the wakeup speed of the low dropout linear regulator is increased, and the wakeup time of the low dropout linear regulator is shortened.

Description

Technical Field

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

[0002] As a key component of electronic products, chips usually have multiple power consumption modes. Chips switch between multiple power consumption modes to meet daily needs. However, switching between power consumption modes often takes time. The switching time of chip power consumption modes mainly depends on the establishment speed of power supply and clock.

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

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

[0005] A technical solution adopted in the present application is: providing a driving circuit suitable for a low-voltage difference linear regulator, 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; wherein 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 greater than the accuracy 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 based on the control signal, output a target bias current and a first reference voltage to the low-voltage difference linear regulator in a first time period, so that the low-voltage difference linear regulator switches from a first power consumption mode to a second power consumption mode, and outputs a second reference voltage to the low-voltage difference 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 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 generating module in the first time period.

[0006] In one embodiment, the bias current generating module includes: a first current source and a second current source, wherein the input end of the first current source is coupled to the 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; wherein 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, and the accuracy of the first bias current is greater than the accuracy of the second bias current.

[0007] In one embodiment, the bias current generating module further includes: at least two auxiliary current sources, an input end of each auxiliary current source is coupled to the working voltage end, and an output end of each auxiliary current source is coupled to the selection module for generating an 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, wherein 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 ends of the first current source and the second current source, and the first end of the first switch is coupled to the low voltage difference 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; wherein 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 the target bias current to the low voltage difference linear regulator.

[0009] In one embodiment, the bias current generating module includes: a first current source and at least two second current sources, the input end of the first current source is coupled to the working voltage end, and the output end of the first current source is coupled to the selection module; the input end of each second current source is coupled to the working voltage end, and the output end of each second current source is coupled to the selection module; wherein 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 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 the target bias current during the time when the first current source generates the first bias current and the reference voltage generating 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 generating module generates the second reference voltage.

[0010] In one embodiment, the selection module includes: a control unit, a first inverter, a first switch, a third switch and a fourth switch, wherein the input end of the first inverter is coupled to the control unit; the second end of the first switch is coupled to the low voltage difference linear regulator; the control end of the third switch is coupled to the input end of the first inverter, the first end of the third switch is coupled to the output end of the first current source, and the second end of the third switch is coupled to the first end of the first switch; the control end of the fourth switch is coupled to the output end of the first inverter, the first end of the fourth switch is coupled to the output end of the auxiliary current source, and the second end of the fourth switch is coupled to the first end of the third switch; wherein the control unit controls the third switch to be disconnected, the first switch and the fourth switch to be turned on, and the second bias current is used as the target bias current during the time when the first current source generates the first bias current and the reference voltage generating 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 disconnected, and the first bias current is used as the target bias current after the first current source generates the first bias current and the reference voltage generating module generates the second reference voltage.

[0011] In one embodiment, the reference voltage generating module includes: a first reference voltage generating unit and a second reference voltage generating unit, the first reference voltage generating unit is coupled to the selection module to generate a first reference voltage; the second reference voltage generating unit is coupled to the selection module; wherein the first reference voltage generating unit is used to generate a first reference voltage; and the second reference voltage generating unit is used to generate a second reference voltage within a first time period.

[0012] In one embodiment, the selection module includes: a control unit, a second inverter, a fifth switch and a sixth switch, wherein the input end of the second inverter is coupled to the control unit; the control end of the fifth switch is coupled to the output end of the second inverter, the first end of the fifth switch is coupled to the output end of the first reference voltage generating unit, and the second end of the fifth switch is coupled to the low voltage difference linear regulator; the control end of the sixth switch is coupled to the input end of the second inverter, the first end of the sixth switch is coupled to the output end of the second reference voltage generating unit, and the second end of the sixth switch is coupled to the second end of the fifth switch; wherein the control unit controls the fifth switch to be turned on and the sixth switch to be turned off in a first time period based on a control signal, and outputs the first reference voltage to the low voltage difference linear regulator, thereby switching the low voltage difference linear regulator 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 voltage difference linear regulator.

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

[0014] The present application also provides a driving method for a low voltage difference linear regulator, wherein the low voltage difference linear regulator is connected to a driving circuit, wherein the driving circuit comprises: a reference voltage generating module, a bias current generating module and a selection module, wherein the selection module is respectively 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 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 comprises:

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

[0016] After the first time period, the control selection module outputs a second reference voltage to the low voltage difference linear regulator to maintain a 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.

[0017] The present application also provides a chip, which includes a low voltage dropout linear regulator and a driving module. The driving module is connected to the low voltage dropout linear regulator, and the driving module includes the driving circuit as described above.

[0018] The present application provides a driving circuit for a low-voltage difference linear regulator, which includes: a reference voltage generating module, a bias current generating module and a selection module, wherein the selection module is connected to the reference voltage generating module and the bias current generating module respectively; wherein 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 greater than the accuracy 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 based on the control signal, outputs a target bias current and a first reference voltage to the low-voltage difference linear regulator in a first time period, thereby switching the low-voltage difference linear regulator from a first power consumption mode to a second power consumption mode, and outputs a second reference voltage to the low-voltage difference 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 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. Through the above method, the bias current generating module is improved, and the low-precision first reference voltage that maintains the first power consumption mode is used to support the low-voltage difference linear regulator to switch from the first power consumption mode to the second power consumption mode during the first time period, so that the power consumption mode is switched while the high-precision second reference voltage is established, and the target bias current gradually increases to a preset value over time, and there is no need to wait for the second reference voltage to be established and the bias current corresponding to the second power consumption mode to be established before switching the power consumption mode, and the second reference voltage is output to the low-voltage difference linear regulator after the first time period to maintain the second power consumption mode, thereby accelerating the switching speed of the low-voltage difference linear regulator to the second power consumption mode, reducing the overall switching time of the low-voltage difference linear regulator to the second power consumption mode, and improving the stability of the output voltage of the low-voltage linear regulator when the two power consumption modes are switched. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

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

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

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

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

[0024] Figure 5 is a structural schematic diagram of a fifth embodiment of a driving circuit for a low voltage dropout linear regulator provided by the present application;

[0025] Figure 6 It is a structural schematic diagram of an embodiment of a low voltage dropout linear regulator provided by the present application;

[0026] Figure 7 It is a timing diagram of a driving circuit of a low voltage dropout linear regulator provided by the present application;

[0027] Figure 8 It is a flow chart of a driving method of a low voltage dropout linear regulator provided by the present application;

[0028] Fig. 9 It is a schematic diagram of the structure of a chip embodiment provided by the present application. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It will be appreciated that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some but not all structures related to the present application are shown in the drawings. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the art without making creative work are within the scope of protection of the present application.

[0030] The terms "first", "second", etc. in this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

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

[0032] See also Figure 1 , Figure 1 1 is a schematic diagram of the structure of the first embodiment of the driving circuit of the low voltage drop 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.

[0033] The reference voltage generating module 10 is used to generate a first reference voltage LPBG_VREF and a second reference voltage HPBG_VREF; the accuracy of the second reference voltage HPBG_VREF is greater than the accuracy of the first reference voltage LPBG_VREF.

[0034] The bias current generating module 20 is used to generate a target bias current IB_LDO_HP.

[0035] The selection module 30 is used to receive the 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 voltage difference linear regulator in the first time period, so that the low voltage difference linear regulator switches from the first power consumption mode to the second power consumption mode, and outputs the second reference voltage HPBG_VREF to the low voltage difference 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.

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

[0037] Exemplarily, the working modes of the low-voltage difference linear regulator include a low-power consumption mode and a normal mode. In the low-power consumption mode, the driving capability of the low-voltage difference linear regulator is relatively weak, and it mainly supplies power to a small number of modules in the low-power consumption mode. In the normal mode, the driving capability of the low-voltage difference linear regulator is relatively strong, and it can supply power to all functional modules at the same time. In one 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). At the same time, the target bias current IB_LDO_HP gradually increases to a preset value over time to improve the accuracy of the output voltage and current of the low dropout linear regulator.

[0039] For example, the current demand of the load may change with the change of the working state. In order to ensure that the low-dropout linear regulator can provide a stable output voltage and current while reducing unnecessary power consumption, the low-dropout linear regulator needs to switch between low-power mode and normal mode. When the load current demand is low, the low-dropout linear regulator may enter the low-power mode to reduce power consumption. When the load current demand is high, the low-dropout linear regulator will wake 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 static current of the low-dropout linear regulator, which is used to maintain a stable output voltage and current. In the low power consumption mode, the output accuracy requirement of the low-dropout linear regulator is low, and a low-precision first reference voltage LPBG_VREF will be used.

[0041] In normal mode, the output accuracy of the low-dropout linear regulator is high, requiring high reference voltage accuracy and bias current accuracy. 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 low power mode, the bias current accuracy is low, and in normal mode, the bias current accuracy is high.

[0042] Exemplarily, when the low dropout linear regulator wakes up, its 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 also gradually increases to a preset value.

[0043] In this embodiment, during the time period of switching from the first power consumption mode to the second power consumption mode, the reference voltage and the bias current are always present, which can ensure that there is no need to wait for the bias current to be established when switching modes, effectively reducing the wake-up time of the low voltage difference linear regulator.

[0044] See also Figure 2 and Figure 3 , Figure 2 and Figure 3 1 is a schematic diagram of the structure of the second embodiment and the third embodiment of the driving circuit of the low voltage drop 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 generating module 10 is used to generate a first reference voltage LPBG_VREF and a second reference voltage HPBG_VREF; the accuracy of the second reference voltage HPBG_VREF is greater than the accuracy of the first reference voltage LPBG_VREF.

[0046] The bias current generating module 20 is used to generate a target bias current IB LDO HP.

[0047] The selection module 30 is used to receive the 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 voltage difference linear regulator in the first time period, so that the low voltage difference linear regulator switches from the first power consumption mode to the second power consumption mode, and outputs the second reference voltage HPBG_VREF to the low voltage difference 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.

[0048] In some optional embodiments, such as Figure 2 As shown, the bias current generating module 20 includes: a first current source S1 and a second current source S2, wherein the input end of the first current source S1 is coupled to the working voltage end, and the output end of the first current source S1 is coupled to the selection module 30; the input end of the second current source S2 is coupled to the working voltage end, and the output end of the second current source S2 is coupled to the selection module 30; wherein, the first current source S1 is used to generate a first bias current HPBG_IBIAS; the second current source S2 is used 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 accuracy of the first bias current HPBG_IBIAS is greater than the accuracy of the second bias current LPBG_IBIAS.

[0049] Exemplarily, the current source is used to provide a bias current to the error amplifier in the low-dropout linear regulator. The performance of the error amplifier is affected by the accuracy of the bias current. The accuracy of the bias current will affect the gain and other parameters of the error amplifier, thereby affecting the output of the low-dropout linear regulator. In the first power consumption mode, the driving capability of the low-dropout linear regulator is weak, and the accuracy requirement for the bias current is low. In the second power consumption mode, the accuracy requirement for the bias current is high. 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. During the wake-up period 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] Among them, the ratio of the first bias current HPBG_IBIAS to the second bias current LPBG_IBIAS in the target bias current IB_LDO_HP can be selected according to the requirements of the error amplifier on current accuracy and wake-up speed. The smaller the ratio of the second bias current LPBG_IBIAS, the higher the accuracy of the target bias current IB_LDO_HP, and the higher the ratio 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 includes: a control unit 31 and a first switch SW1, wherein the control end of the first switch SW1 is coupled to the control unit 31, the first end of the first switch SW1 is coupled to the 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. The control unit 31 is used to control the first switch SW1 to be turned on so that the bias current generating module 20 outputs the target bias current IB_LDO_HP to the low-dropout linear regulator.

[0052] Exemplarily, the control unit 31 may be a device such as an analog switch controller, and the control unit 31 receives the control signal HPLDO_EN and controls the on and 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 power supply is output to the low voltage drop linear regulator.

[0053] In some optional embodiments, such as Figure 3 As shown, Figure 3 The driving circuit 100 of the low voltage drop linear regulator shown in FIG. Figure 2The main difference of the driving circuit 100 of the low voltage drop linear regulator shown in FIG. 1 is that the auxiliary current source S3 and the second switch SW2 are added. Therefore, the auxiliary current source S3 and the second switch SW2 are mainly described below. For other components in the driving circuit 100 of the low voltage drop linear regulator, please refer to FIG. Figure 2 The relevant description of the embodiment shown, for example Figure 3 The first switch SW1 in Figure 2 The description of the first switch SW1 in will not be repeated here.

[0054] In some embodiments, the bias current generating module 20 further includes: at least two auxiliary current sources S3, the input end of each auxiliary current source S3 is coupled to the working voltage end, and the 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 period of the low-dropout linear regulator, which helps to speed up 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 increases the driving capability of the low-dropout linear regulator in the first power consumption mode. The number of auxiliary current sources S3 can be increased according to the needs of the circuit.

[0056] In some embodiments, the selection module 30 also includes: 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 a first end of the second switch SW2 is coupled to the first end of the first switch SW1; wherein the control unit 31 is used to control the first switch SW1 and the second switch SW2 to be turned on, so that the bias current generating module 20 outputs the target bias current IB_LDO_HP to the low voltage difference 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 fully established, 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 delay, the second switch SW2 is turned off to reduce the power consumption of the low voltage drop linear regulator.

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

[0059] See also Figure 4 , Figure 4 1 is a schematic diagram of a fourth embodiment of a driving circuit of a low voltage dropout linear regulator provided by the present application. The driving circuit 100 comprises a reference voltage generating module 10, a bias current generating module 20 and a selection module 30, wherein the selection module 30 is connected to the reference voltage generating module 10 and the bias current generating module 20 respectively.

[0060] The reference voltage generating module 10 is used to generate a first reference voltage LPBG_VREF and a second reference voltage HPBG_VREF; 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 generating module 20 is used to generate a target bias current IB_LDO_HP.

[0062] The selection module 30 is used to receive the 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 voltage difference linear regulator in the first time period, so that the low voltage difference linear regulator switches from the first power consumption mode to the second power consumption mode, and outputs the second reference voltage HPBG_VREF to the low voltage difference 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 generating module 20 includes: a first current source S1 and at least two second current sources S2, the input end of the first current source S1 is coupled to the working voltage end, and the output end of the first current source S1 is coupled to the selection module 30; the input end of each second current source S2 is coupled to the working voltage end, and the output end of each second current source S2 is coupled to the selection module 30; wherein the first current source S1 is used to generate a first bias current HPBG_IBIAS; the second current source S2 is used to generate a second bias current LPBG_IBIAS; the accuracy of the first bias current HPBG_IBIAS is greater than that of the second bias current LP The selection module 30 uses the second bias current LPBG_IBIAS as the target bias current IB_LDO_HP 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 selection module 30 uses 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 needs of the circuit.

[0064] In some embodiments, the selection module 30 includes: a control unit 31, a first inverter A1, a first switch SW1, a third switch SW3, and a fourth switch SW4. The input end of the first inverter A1 is coupled to the control unit 31; the second end of the first switch SW1 is coupled to the low voltage drop linear regulator; the control end of the third switch SW3 is coupled to the input end of the first inverter A1, the first end of the third switch SW3 is coupled to the output end of the first current source S1, and the second end of the third switch SW3 is coupled to the first end of the first switch SW1; the control end of the fourth switch SW4 is coupled to the output end of the first inverter A1, the first end of the fourth switch SW4 is coupled to the output end of the auxiliary current source S3, and the second end of the fourth switch SW4 is coupled to the first end of the third switch SW3; wherein the control unit 31 generates a first bias current HPBG_IBIAS in the first current source S1 And during the time when the reference voltage generating module 10 generates the second reference voltage HPBG_VREF, the third switch SW3 is controlled to be turned off, the first switch SW1 and the fourth switch SW4 are turned on, and the second bias current LPBG_IBIAS is used 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 generating module 10 generates the second reference voltage HPBG_VREF, the control unit 31 controls the first switch SW1 and the third switch SW3 to be turned on, and the fourth switch SW4 to be turned off, and the first bias current HPBG_IBIAS is used as the target bias current IB_LDO_HP.

[0065] For example, the accuracy of the second bias current LPBG_IBIAS is low, so that the accuracy of the target bias current IB_LDO_HP is affected. 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 generating module 10 generates the second reference voltage HPBG_VREF, the fourth switch SW4 is controlled to be turned on, so that the second current source S2 and the loop of the low voltage difference linear regulator are turned on, and the target bias current IB_LDO_HP is only provided by the second current source S2, and the number of second current sources S2 can be increased according to the requirements of the circuit to improve the wake-up speed of the low voltage difference linear regulator; after the first current source S1 generates the first bias current HPBG_IBIAS and the reference voltage generating module 10 generates the second reference voltage HPBG_VREF, the fourth switch SW4 is controlled to be turned off and the third switch SW3 is turned on, so that the first current source S1 and the loop of the low voltage difference linear regulator are turned on, and the target bias current IB_LDO_HP is only provided by the first current source S1, thereby improving the output accuracy of the low voltage difference linear regulator.

[0066] See also Figure 5 , Figure 5 1 is a schematic diagram of the structure of the fifth embodiment of the driving circuit of the low voltage drop 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.

[0067] The reference voltage generating module 10 is used to generate a first reference voltage LPBG_VREF and a second reference voltage HPBG_VREF; the accuracy of the second reference voltage HPBG_VREF is greater than the accuracy of the first reference voltage LPBG_VREF.

[0068] The bias current generating module 20 is used to generate a target bias current IB_LDO_HP.

[0069] The selection module 30 is used to receive the 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 voltage difference linear regulator in the first time period, so that the low voltage difference linear regulator switches from the first power consumption mode to the second power consumption mode, and outputs the second reference voltage HPBG_VREF to the low voltage difference 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 generating module 10 includes: a first reference voltage generating unit 11 and a second reference voltage generating unit 12, the first reference voltage generating unit 11 is coupled to the selection module 30; the second reference voltage generating unit 12 is coupled to the selection module 30; wherein the first reference voltage generating unit 11 is used to generate a first reference voltage LPBG_VREF; the second reference voltage generating unit 12 is used to generate a second reference voltage HPBG_VREF within a first time period.

[0071] In some embodiments, the selection module 30 includes: 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 generating unit 11, and the second end of the fifth switch SW5 is coupled to the low voltage difference 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 generating 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 and the sixth switch SW6 to be turned off in the first time period based on the control signal HPLD0_EN, and outputs the first reference voltage LPBG_VREF to the low voltage difference linear regulator, thereby switching the low voltage difference linear regulator from the first power consumption mode to the second power consumption mode, and controls the fifth switch SW5 to be turned off and the sixth switch SW6 to be turned on after the first time period, and outputs the second reference voltage HPBG_VREF to the low voltage difference linear regulator.

[0072] Exemplarily, the second inverter A2 is used to invert the level of the output signal of the control unit 31, that is, when the fifth switch SW5 is turned on, the sixth switch SW6 is turned off, and when the fifth switch SW5 is turned off, the sixth switch SW6 is turned on. 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] See also Figure 6 , Figure 6 It is a structural schematic diagram of an embodiment of a low voltage dropout linear regulator provided by the present application.

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

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

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

[0077] The selection module 30 is used to receive the 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 voltage difference linear regulator in the first time period, so that the low voltage difference linear regulator switches from the first power consumption mode to the second power consumption mode, and outputs the second reference voltage HPBG_VREF to the low voltage difference 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.

[0078] The low voltage difference linear regulator 600 includes 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; the second end of the second resistor R2 is grounded.

[0079] Among them, when the low voltage difference linear regulator 600 is working, the second error amplifier GMLP receives the bias current LPBG_IBIAS2 output from the fourth current source S4 and the reference voltage signal output from the reference voltage generating module 10, and the first error amplifier GMHP receives the reference voltage signal output from the reference voltage generating module 10 and the target bias current IB_LDO_HP generated by the bias current generating 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 voltage difference linear 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 voltage difference linear 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 will continue to work.

[0080] See also Figure 7 , Figure 7 It is a timing diagram of a driving circuit of a low voltage dropout linear regulator provided in the present application.

[0081] The low dropout linear regulator can be Figure 6 The driving circuit of the low voltage dropout linear regulator 600 is the aforementioned driving circuit 100 and will not be described in detail herein.

[0082] Before waking up, the bias current of the low-dropout linear regulator is provided by the bias current LPBG_IBIAS2 of the second error amplifier GMLP, and the reference voltage is the first reference voltage LPBG_VREF. At this time, 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 waking 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 are kept at a high level, so that the output LDO_OUT of the low-voltage dropout linear regulator is also kept at a high level. 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-voltage dropout linear regulator is always kept at a high level. Among them, t1 represents the delay time of the control signal HPLDO_EN, and t2 represents the establishment time of the second reference voltage HPBG_VREF. In order to ensure that the second reference voltage HPBG_VREF is fully established before switching the reference voltage, the t1 time needs to be greater than t2.

[0084] Through the above method, the low voltage drop linear regulator keeps a stable output when it wakes up, and the wake-up time can be considered to be 0us.

[0085] See also Figure 8 , Figure 8 The present invention provides a flow chart of a driving method of a low voltage difference linear regulator provided by the present invention. The low voltage difference 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. The driving method includes:

[0086] Step S81: sending a control signal to the selection module to control the selection module to output a target bias current and a first reference voltage to the low dropout linear regulator in a first time period, thereby switching 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 voltage difference 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] See also Fig. 9 , Fig. 9 The chip 1000 includes: a low voltage dropout linear regulator 200 and a driving module 300, wherein the driving module 300 is connected to the low voltage dropout linear regulator 100, and the driving module 300 includes the driving circuit 100 as described above.

[0089] In the several embodiments provided in this application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device implementation described above is only illustrative, for example, the division of the modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple 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 may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0091] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0092] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A driving circuit suitable for a low voltage drop linear regulator, characterized in that: The driving circuit comprises: a reference voltage generating module, a bias current generating module and a selection module, wherein the selection module is connected to the reference voltage generating module and the bias current generating module respectively; Wherein, 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 greater than the accuracy 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 based on the control signal, output the target bias current and the first reference voltage to the low-voltage difference linear regulator in a first time period, so that the low-voltage difference linear regulator switches from a first power consumption mode to a second power consumption mode, and outputs the second reference voltage to the low-voltage difference 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 gradually increases to a preset value over time; the second reference voltage is established by the reference voltage generation module in the first time period.

2. The driving circuit according to claim 1, characterized in that: The bias current generating module comprises: a first current source and a second current source, wherein an input terminal of the first current source is coupled to a working voltage terminal, and an output terminal of the first current source is coupled to the selecting module; an input terminal of the second current source is coupled to the working voltage terminal, and an output terminal of the second current source is coupled to the selecting module; Wherein, 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, and the accuracy of the first bias current is greater than the accuracy of the second bias current.

3. The driving circuit according to claim 2, characterized in that: The bias current generating module also includes: At least two auxiliary current sources, each of which has an input terminal coupled to a working voltage terminal and an output terminal coupled to the selection module, for generating an 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.

4. The driving circuit according to claim 3, characterized in that: The selection module includes: a control unit, a first switch and a second switch, wherein a control end of the first switch is coupled to the control unit, a first end of the first switch is coupled to the output ends of the first current source and the second current source, and a first end of the first switch is coupled to the low voltage drop linear regulator; a control end of the second switch is coupled to the control unit, a first end of the second switch is coupled to the output end of the auxiliary current source, and a first end of the second switch is coupled to the first end 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 the target bias current to the low voltage drop linear regulator.

5. The driving circuit according to claim 1, characterized in that: The bias current generating module comprises: a first current source and at least two second current sources, wherein an input terminal of the first current source is coupled to a working voltage terminal, and an output terminal of the first current source is coupled to the selecting module; an input terminal of each of the second current sources is coupled to the working voltage terminal, and an output terminal of each of the second current sources is coupled to the selecting module; Wherein, 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 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 the 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; 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 driving circuit according to claim 5, characterized in that: The selection module includes: a control unit, a first inverter, a first switch, a third switch and a fourth switch, wherein 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 voltage drop linear regulator; a control end of the third switch is coupled to an input end of the first inverter, a first end of the third switch is coupled to an 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 a second end of the third switch; The control unit controls the third switch to be disconnected and the first switch and the fourth switch to be turned on during the time when the first current source generates the first bias current and the reference voltage generating module generates the second reference voltage, and uses the second bias current as the target bias current; After the first current source generates the first bias current and the reference voltage generating 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, and uses the first bias current as the target bias current.

7. The driving circuit according to claim 1, characterized in that: The reference voltage generating module comprises: a first reference voltage generating unit and a second reference voltage generating unit, the first reference voltage generating unit is coupled to the selection module, and the second reference voltage generating unit is coupled to the selection module; Wherein, the first reference voltage generating unit is used to generate the first reference voltage, and the second reference voltage generating unit is used to generate the second reference voltage within the first time period; and / or The selection module includes: a control unit, a second inverter, a fifth switch and a sixth switch, wherein the input end of the second inverter is coupled to the control unit; the control end of the fifth switch is coupled to the output end of the second inverter, the first end of the fifth switch is coupled to the output end of the first reference voltage generating unit, and the second end of the fifth switch is coupled to the low voltage difference linear regulator; the control end of the sixth switch is coupled to the input end of the second inverter, the first end of the sixth switch is coupled to the output end of the second reference voltage generating unit, and the second end of the sixth switch is coupled to the second end of the fifth switch; Among them, the control unit controls the fifth switch to be turned on and the sixth switch to be turned off in the first time period based on the control signal, and outputs the first reference voltage to the low-voltage difference linear regulator, so that the low-voltage difference linear regulator switches 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-voltage difference linear regulator.

8. The driving circuit according to any one of claims 1 to 7, characterized in that: The first time period is greater than or equal to the establishment time of the second reference voltage.

9. A driving method for a low voltage dropout linear regulator, characterized in that: The low voltage difference linear regulator is connected to a driving circuit, and the driving circuit includes: a reference voltage generating module, a bias current generating module and a selection module, and the selection module is respectively 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 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: 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 regulator in a first time period, so that the low-dropout linear regulator switches from a first power consumption mode to a second power consumption mode; After the first time period, the selection module is controlled to output the 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.

10. A chip, characterized in that: The chips shown include: Low dropout linear regulator; A driving module is connected to the low voltage drop linear regulator, and the driving module includes the driving circuit according to any one of claims 1 to 8.

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