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CN114690828A - LDO circuit, control method, chip and electronic equipment - Google Patents

LDO circuit, control method, chip and electronic equipment Download PDF

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Publication number
CN114690828A
CN114690828A CN202210395751.2A CN202210395751A CN114690828A CN 114690828 A CN114690828 A CN 114690828A CN 202210395751 A CN202210395751 A CN 202210395751A CN 114690828 A CN114690828 A CN 114690828A
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CN
China
Prior art keywords
power supply
circuit
level
ldo
ldo circuit
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CN202210395751.2A
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Chinese (zh)
Inventor
殷文杰
陈敏
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Chipsea Technologies Shenzhen Co Ltd
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Chipsea Technologies Shenzhen Co Ltd
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Priority to CN202210395751.2A priority Critical patent/CN114690828A/en
Publication of CN114690828A publication Critical patent/CN114690828A/en
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    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05FSYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
    • G05F1/00Automatic systems in which deviations of an electric quantity from one or more predetermined values are detected at the output of the system and fed back to a device within the system to restore the detected quantity to its predetermined value or values, i.e. retroactive systems
    • G05F1/10Regulating voltage or current
    • G05F1/46Regulating voltage or current wherein the variable actually regulated by the final control device is dc
    • G05F1/56Regulating voltage or current wherein the variable actually regulated by the final control device is dc using semiconductor devices in series with the load as final control devices

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Automation & Control Theory (AREA)
  • Logic Circuits (AREA)
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Abstract

The application provides an LDO circuit, a control method, a chip and electronic equipment, and belongs to the technical field of electronics. The LDO circuit comprises an output circuit comprising a plurality of power supply branches; the output circuit is configured to: and when the output voltage of the LDO circuit undershoots, at least one switched-off power supply branch is switched on. By adopting the method and the device, the quick response to the undershoot of the output voltage of the LDO can be realized.

Description

LDO circuit, control method, chip and electronic equipment
Technical Field
The application relates to the technical field of electronics, in particular to an LDO circuit, a control method, a chip and electronic equipment.
Background
A Low-Dropout Regulator (LDO) circuit is widely applied to different electronic devices by virtue of its simple circuit, small size, Low power consumption and Low cost, and provides power for each module therein.
When the output voltage of the LDO circuit is stable, the output voltage of the LDO circuit changes abruptly with the change of the load current, such as switching from a light load to a heavy load, and undershoot occurs. The undershoot needs a certain time to recover to a stable value, which affects the transient response of the LDO, and further affects the normal operation of the module using the output voltage of the LDO as the power supply.
Disclosure of Invention
In order to solve the problems in the prior art, embodiments of the present application provide an LDO circuit, a control method, a chip, and an electronic device, which can implement a fast response to an undershoot of an output voltage. The technical scheme is as follows:
according to an aspect of the application, there is provided an LDO circuit, comprising an output circuit comprising a plurality of power supply branches;
the output circuit is configured to:
and when the output voltage of the LDO circuit undershoots, at least one switched-off power supply branch is switched on.
Optionally, the output circuit is configured to:
and when the output voltage of the LDO circuit undershoots, sequentially conducting the plurality of switched-off power supply branches.
Optionally, the output circuit is further configured to:
and when the output voltage of the LDO circuit is overshot, at least one conducting power supply branch is switched off.
Optionally, the output circuit is configured to:
and when the output voltage of the LDO circuit is overshot, the plurality of conducted power supply branches are sequentially turned off.
Optionally, the LDO circuit further includes a first control module, the first control module is configured to generate a first control signal for the power supply branch, the first control signal includes an off level for turning off the power supply branch and an on level for turning on the power supply branch;
the first control module is configured to:
when the output voltage of the LDO circuit undershoots, the first control signal of at least one power supply branch circuit is adjusted from a turn-off level to a turn-on level.
Optionally, the first control module is configured to:
when the output voltage of the LDO circuit undershoots, the first control signals of the plurality of power supply branches are sequentially adjusted from the turn-off level to the turn-on level.
Optionally, the first control module is further configured to:
when the output voltage of the LDO circuit is overshot, the first control signal of at least one power supply branch is adjusted from a conducting level to a switching-off level.
Optionally, the first control module is configured to:
when the output voltage of the LDO circuit is overshot, the first control signals of the plurality of power supply branches are sequentially adjusted from the on level to the off level.
Optionally, the first control module includes an output voltage detection module and a switch regulation and control module;
the output voltage detection module is configured to output an undershoot signal when the output voltage undershoots, and transmit the undershoot signal to the switching regulation and control module;
the switch regulation and control module is configured to adjust the first control signal of at least one power supply branch from an off level to an on level when the undershoot signal is received.
Optionally, the output voltage detection module is further configured to output an overshoot signal when the output voltage overshoots, and transmit the overshoot signal to the switch regulation and control module;
the switch regulation module is further configured to adjust the first control signal of the at least one power supply branch from an on level to an off level upon receiving the overshoot signal.
Optionally, the output circuit is further configured to:
conducting at least one power supply branch during power-up of the LDO circuit.
Optionally, the output circuit is configured to:
sequentially turning on a plurality of power supply branches during power-up of the LDO circuit.
Optionally, the LDO circuit further comprises a second control module for generating a second control signal for the power supply branch during power-up of the LDO circuit, the second control signal comprising an off level for turning off the power supply branch and an on level for turning on the power supply branch;
the second control module is configured to:
adjusting a second control signal of at least one power supply branch from an off level to an on level during power-up of the LDO circuit.
Optionally, the second control module is configured to:
during the power-on of the LDO circuit, the second control signals of the plurality of power supply branches are sequentially adjusted from an off level to an on level.
Optionally, the LDO circuit further comprises an amplifying circuit, a first feedback resistance unit, and a second feedback resistance unit, wherein,
the first input end of the amplifying circuit is used for receiving a reference voltage, the second input end of the amplifying circuit is used for receiving a feedback voltage between the first feedback resistance unit and the second feedback resistance unit, and the output end of the amplifying circuit is connected with the first input end of the output circuit;
the second input end of the output circuit is used for receiving power supply voltage, and the output end of the output circuit is connected with the output end of the LDO circuit;
the first end of the first feedback resistance unit is connected with the output end of the LDO circuit, and the second end of the first feedback resistance unit is connected with the first end of the second feedback resistance unit;
and the second end of the second feedback resistance unit is connected with the ground.
According to another aspect of the present application, there is provided a control method of an LDO circuit including an output circuit including a plurality of power supply branches, the method including:
outputting an output voltage of the LDO circuit based on the output circuit;
and when the output voltage of the LDO circuit undershoots, at least one switched-off power supply branch is switched on.
According to another aspect of the present application, a chip is provided, which includes the LDO circuit.
According to another aspect of the present application, an electronic device is provided, which includes the LDO circuit described above.
In this application, the LDO circuit can include output circuit, and output circuit includes a plurality of power supply branch road. When the output voltage generates undershoot, the power supply branch circuit is conducted to realize quick response to the undershoot.
Drawings
Further details, features and advantages of the present application are disclosed in the following description of exemplary embodiments, which is to be read in connection with the accompanying drawings, in which:
FIG. 1 shows a schematic diagram of an LDO circuit provided in accordance with an exemplary embodiment of the present application;
FIG. 2 shows a schematic diagram of an LDO circuit provided in accordance with an exemplary embodiment of the present application;
FIG. 3 shows a schematic diagram of an LDO circuit provided according to an exemplary embodiment of the present application;
FIG. 4 illustrates a first control module schematic provided in accordance with an exemplary embodiment of the present application;
FIG. 5 shows a schematic diagram of an LDO circuit provided according to an exemplary embodiment of the present application;
FIG. 6 shows a schematic diagram of an LDO circuit provided according to an exemplary embodiment of the present application;
FIG. 7 shows a schematic diagram of an LDO circuit provided in accordance with an exemplary embodiment of the present application;
FIG. 8 shows a schematic diagram of an LDO circuit provided in accordance with an exemplary embodiment of the present application;
FIG. 9 illustrates a timing diagram provided in accordance with an exemplary embodiment of the present application;
FIG. 10 illustrates a timing diagram provided in accordance with an exemplary embodiment of the present application;
FIG. 11 illustrates a timing diagram provided in accordance with an exemplary embodiment of the present application;
fig. 12 shows a flowchart of a control method of an LDO circuit provided according to an exemplary embodiment of the present application.
Detailed Description
Embodiments of the present application will be described in more detail below with reference to the accompanying drawings. While certain embodiments of the present application are shown in the drawings, it should be understood that the present application may be embodied in various forms and should not be construed as limited to the embodiments set forth herein, but rather are provided for a more thorough and complete understanding of the present application. It should be understood that the drawings and embodiments of the present application are for illustration purposes only and are not intended to limit the scope of the present application.
The term "include" and variations thereof as used herein are open-ended, i.e., "including but not limited to". The term "based on" is "based, at least in part, on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Relevant definitions for other terms will be given in the following description. It should be noted that the terms "first", "second", and the like in the present application are only used for distinguishing different devices, modules or units, and are not used for limiting the order or interdependence relationship of the functions performed by the devices, modules or units.
It is noted that references to "a", "an", and "the" modifications in this application are intended to be illustrative rather than limiting, and that those skilled in the art will recognize that reference to "one or more" unless the context clearly dictates otherwise.
The names of messages or information exchanged between a plurality of devices in the embodiments of the present application are for illustrative purposes only, and are not intended to limit the scope of the messages or information.
The embodiment of the application provides an LDO circuit, and the LDO circuit can be integrated in a chip or arranged in an electronic device.
Referring to the schematic diagram of the LDO circuit shown in fig. 1, the LDO circuit may include an output circuit including a plurality of power supply branches.
In this application, the fast response to the transient variation of the load is realized by turning off or turning on the power supply branch, and therefore, the LDO circuit may further include a basic circuit for realizing the low dropout linear voltage stabilization function, and the basic circuit may adopt the existing circuit structure, and this embodiment does not limit this. Alternatively, fig. 2 shows a possible LDO circuit, which may include the above output circuit, an amplifying circuit, a first feedback resistance unit, and a second feedback resistance unit, wherein: the first input end of the amplifying circuit is used for receiving a reference voltage, the second input end of the amplifying circuit is used for receiving a feedback voltage between the first feedback resistance unit and the second feedback resistance unit, and the output end of the amplifying circuit is connected with the first input end of the output circuit; the second input end of the output circuit is used for receiving power supply voltage, and the output end of the output circuit is connected with the output end of the LDO circuit; the first end of the first feedback resistance unit is connected with the output end of the LDO circuit, and the second end of the first feedback resistance unit is connected with the first end of the second feedback resistance unit; the second end of the second feedback resistance unit is connected with the ground.
The configuration of the output circuit will be described below, and the rest of the circuits can be implemented by using the existing principle, and the implementation principle of the rest of the circuits is not described in this embodiment.
The output circuit may be configured to: and when the output voltage of the LDO circuit undershoots, at least one switched-off power supply branch is switched on. Optionally, it may be further configured to: and when the output voltage of the LDO circuit overshoots, at least one conducting power supply branch is switched off.
In one possible implementation, after the LDO is powered on and the output voltage is stabilized, a stable power supply can be provided for other modules. At this time, there may be at least one power supply branch in a conducting state to provide a certain voltage for the output voltage.
When the load current of the LDO circuit suddenly changes and the LDO circuit is switched from light load to heavy load, the output voltage of the LDO circuit suddenly changes, and undershoot is generated. At this time, the power supply branch in the at least partially turned-off state may be turned on, so as to increase the voltage provided to the output voltage and facilitate the output voltage of the LDO circuit to return to a stable value.
Alternatively, when the load current of the LDO circuit abruptly changes from a heavy load to a light load, the output voltage of the LDO circuit will abruptly change, resulting in overshoot. At this time, the power supply branch in the at least partially conducting state may be turned off, so as to reduce the voltage provided to the output voltage and facilitate the output voltage of the LDO circuit to return to a stable value.
It should be noted that after the response overshoot, the switched-off power supply branch may not be turned on when the output voltage is in a steady state. For example, in response to the first overshoot, power supply branch a is turned off, power supply branch B remains on, power supply branch a is not turned on after stabilization, and power supply branch B is turned off in response to the second overshoot. Similarly, after responding to the undershoot, the turned-on power supply branch may not be turned off when the output voltage is in a stable state.
Alternatively, the power supply branch that is turned off in response to the overshoot and the power supply branch that is turned on in response to the undershoot may be the same or different. For example, the supply branch a may be turned off in response to the overshoot, and the supply branch a may be turned on in response to the undershoot, or the supply branch B that is turned off may be turned on.
Alternatively, the number of supply branches switched off in response to the overshoot and the number of supply branches switched on in response to the undershoot may be the same or different. For example, 3 power supply branches are turned off in response to the overshoot, and 3 power supply branches may be turned on in response to the undershoot, or 2 power supply branches may be turned on. Further optionally, the first number of supply branches that are turned off in response to the overshoot may be determined in accordance with a magnitude of the overshoot voltage, the second number of supply branches that are turned on in response to the undershoot may be determined in accordance with a magnitude of the undershoot voltage, and the output circuit may be further configured to: when the output voltage of the LDO circuit overshoots, the first number of the conducted power supply branches are turned off; and when the output voltage of the LDO circuit undershoots, the second number of the switched-off power supply branches are switched on. On the basis, the adaptability of the number of power supply branches for response to the overshoot amplitude or the undershoot amplitude can be improved, and the accuracy of transient response is improved.
Through the configuration mode of the output circuit, when the output voltage of the LDO circuit generates overshoot, at least one conducted power supply branch can be turned off, so that quick response to the overshoot is realized; when the output voltage of the LDO circuit generates undershoot, at least one power supply branch which is turned off can be turned on, and therefore quick response to the undershoot is achieved.
It should be noted that, by increasing or decreasing the conducting number of the power supply branches, the overshoot voltage of the LDO can be pulled down at the instant of turning off the power supply branches, or the undershoot voltage of the LDO can be pulled up at the instant of turning on the power supply branches, so as to alleviate the overshoot or undershoot of the instantaneous voltage caused by the load change. After one or more power supply branches are turned off/on, the output voltage of the LDO circuit is stabilized to the preset reference voltage value again under the action of an operational amplifier feedback loop in the LDO circuit, and the influence of the number of the power supply branches is avoided.
In one possible embodiment, the plurality of supply branches in the output circuit includes at least one supply branch operable to respond to the overshoot and at least one normally-on supply branch. The plurality of power supply branches available for responding to the overshoot means that a basic function of the LDO circuit to output the regulated voltage is not affected when the at least one power supply branch available for responding to the overshoot is all turned off. For example, during operation of the LDO circuit, after one or more power supply branches available for responding to the overshoot are all turned off, the LDO circuit may still maintain the voltage output through the at least one normally-on power supply branch, which may not result in the LDO output voltage being 0. In this example, the number of normally-on supply branches may be set according to the required LDO minimum load capacity, such that the at least one normally-on supply branch can meet the minimum load requirement when all supply branches available to respond to the overshoot are turned off. It should be noted that the at least one normally-on power supply branch is not limited to a fixed power supply branch, and the number of the power supply branches that are turned on in the output circuit may be greater than or equal to the set number.
In one possible embodiment, all the switched-off supply branches can be used to respond to undershoots. For example, when an undershoot occurs, some of the power supply branches that have been turned off may be turned on in sequence, or all of the power supply branches that have been turned off may be turned on in sequence, depending on the magnitude of the undershoot voltage.
Optionally, when the output circuit comprises a plurality of supply branches operable to respond to undershoot, it may be configured to: when the output voltage of the LDO circuit undershoots, the plurality of power supply branches which are switched off are sequentially switched on.
Optionally, when the output circuit comprises a plurality of supply branches operable to respond to the overshoot, it may be configured to: and when the output voltage of the LDO circuit overshoots, the plurality of conducted power supply branches are sequentially turned off.
In a possible embodiment, there are a plurality of power supply branches that are turned on and can respond to overshoot, and when the output voltage generates overshoot, the plurality of power supply branches that can respond to overshoot can be controlled to be turned off in sequence to achieve fast response to overshoot. Compared with the technical scheme of simultaneously turning off a plurality of power supply branches, the time consumption of sequentially turning off the power supply branches is reduced, and the transient power consumption can be reduced.
Similarly, when the output voltage generates undershoot, the plurality of power supply branches can be controlled to be sequentially switched on under the condition that a plurality of power supply branches are switched off, so that fast response to the undershoot is realized. Compared with the technical scheme of simultaneously conducting a plurality of power supply branches, the time consumption for sequentially conducting the power supply branches is reduced, and the transient power consumption can be reduced.
Optionally, referring to the LDO circuit schematic shown in fig. 3, the LDO circuit may further include a first control module, which may be configured to generate a first control signal for the power supply branch, and the first control signal may include an off level for turning off the power supply branch and an on level for turning on the power supply branch.
The first control module may be configured to: when the output voltage of the LDO circuit undershoots, the first control signal of at least one power supply branch circuit is adjusted from the turn-off level to the turn-on level.
Optionally, the first control module may be further configured to: when the output voltage of the LDO circuit is overshot, the first control signal of at least one power supply branch circuit is adjusted from a turn-on level to a turn-off level
Wherein the off level is opposite to the on level. The turn-off level and the turn-on level are adapted to the corresponding power supply branch, for example, when the power supply branch is enabled at a high level, the turn-on level may be a high level, and the turn-off level may be a low level; when the power supply branch is enabled at a low level, the turn-on level may be a low level, and the turn-off level may be a high level. The present embodiment does not limit the specific power supply branch and the enable signal thereof.
In a possible implementation manner, the first control signal output by the first control module may access the corresponding power supply branch. In a stable state, when the first control signal is in a conducting state, the corresponding power supply branch is controlled to be in a conducting state; when the first control signal is in the off-level state, the corresponding power supply branch is controlled to be in the off-state. The first control module can detect the output voltage, determine specific control over the power supply branch circuit through first preset logic when the output voltage generates overshoot, and adjust a first control signal of the power supply branch circuit for responding to the overshoot from a turn-on level to a turn-off level. The power supply branch is switched off when the first control signal jumps from the on level to the off level, so that quick response to the overshoot is realized.
When the output voltage generates an undershoot, specific control of the power supply branch can be determined through the second preset logic, and the first control signal of the power supply branch responding to the undershoot is adjusted from the off level to the on level. The power supply branch circuit is switched on when the first control signal jumps from the turn-off level to the turn-on level, and quick response to undershoot is achieved.
Optionally, the first control module may be configured to, in response to a situation in which the plurality of power supply branches are controlled to achieve a fast response to an undershoot: when the output voltage of the LDO circuit undershoots, the control signals of the plurality of power supply branches are sequentially adjusted from the turn-off level to the turn-on level.
Optionally, the first control module may be configured to, in response to controlling the plurality of supply branches to achieve a fast response to the overshoot: when the output voltage of the LDO circuit overshoots, the control signals of the plurality of power supply branches are sequentially adjusted from the on level to the off level.
In one possible embodiment, the first control module may adjust the plurality of first control signals from the on level to the off level at different times, respectively. Furthermore, the plurality of power supply branches can be controlled to be turned off at different moments, namely, turned off in sequence.
Similarly, the first control module may adjust the plurality of first control signals from the off level to the on level at different times, respectively. Furthermore, the plurality of power supply branches can be controlled to be conducted at different moments, namely, sequentially conducted.
Optionally, the time interval of each two adjacent time instants is the same for each time instant at which the first control signal transitions from the on-level to the off-level, and/or the time interval of each two adjacent time instants is the same for each time instant at which the first control signal transitions from the off-level to the on-level. On the basis, the stability of the output voltage can be ensured.
Optionally, referring to the schematic diagram of the first control module shown in fig. 4, the first control module may include an output voltage detection module and a switching regulation module.
And the output voltage detection module can be configured to output an undershoot signal when the output voltage undershoots, and transmit the undershoot signal to the switching regulation and control module. The switching regulation module may be configured to adjust the first control signal of the at least one power supply branch from an off level to an on level when the undershoot signal is received.
Optionally, the output voltage detection module may be further configured to output the overshoot signal when the output voltage overshoots, and transmit the overshoot signal to the switching regulation module. The switch regulation module may be further configured to adjust the first control signal of the at least one power supply branch from an on level to an off level upon receiving the overshoot signal.
Wherein the overshoot signal and the undershoot signal are opposite. For example, the overshoot signal may be a negative pulse signal and the undershoot signal may be a positive pulse signal, or vice versa. The present embodiment does not limit the specific form of the overshoot signal and the undershoot signal.
In a possible embodiment, an input terminal of the output voltage detection module may be connected to an output terminal of the LDO circuit, and configured to detect an output voltage of the LDO circuit. The output end of the output voltage detection module can be connected with the input end of the switch regulation and control module. The output end of the switch regulation and control module can be connected with a corresponding power supply branch.
The output voltage detection module may be further configured to determine whether an output voltage of the LDO circuit is greater than a first threshold or less than a second threshold. When the output voltage is larger than the first threshold, it indicates that the output voltage overshoots, and at this time, the output voltage detection module may generate an overshoot signal and output the overshoot signal to the switch regulation and control module. When the switch regulation and control module receives the overshoot signal, the specific control of the power supply branch circuit can be determined through the first preset logic, and the first control signal of the power supply branch circuit for responding to the overshoot is adjusted from the conducting level to the switching-off level. Optionally, corresponding to the above-mentioned case of controlling the multiple power supply branches to achieve fast response, the switch regulation and control module may be configured to sequentially adjust the first control signals of the multiple power supply branches from the on level to the off level when receiving the overshoot signal.
When the output voltage is smaller than the second threshold value, the output voltage is indicated to generate an undershoot, and at the moment, the output voltage detection module can generate an undershoot signal and output the undershoot signal to the switch regulation and control module. When the switch regulation and control module receives the undershoot signal, the specific control of the power supply branch circuit can be determined through the second preset logic, and the first control signal of the power supply branch circuit for responding to the overshoot is adjusted from the turn-off level to the turn-on level. Optionally, corresponding to the above-mentioned case of controlling the plurality of power supply branches to achieve fast response, the switch regulation and control module may be configured to adjust the first control signals of the plurality of power supply branches from the off level to the on level in sequence when receiving the undershoot signal.
Optionally, corresponding to the above-mentioned case that the number of the power supply branches used for response is determined according to the overshoot amplitude or the undershoot amplitude, the output voltage detection module may be further configured to, when the output voltage is greater than the first threshold, determine a first number of the power supply branches turned off in response to the overshoot according to the magnitude of the current output voltage, and transmit information of the first number to the switch regulation and control module; and when the output voltage is smaller than a second threshold value, determining a second number of the power supply branches which are conducted in response to the undershoot according to the current output voltage, and transmitting the information of the second number to the switch regulation and control module. When the output voltage is greater than the first threshold, the current output voltage may be an overshoot voltage; when the output voltage is less than the second threshold, the present output voltage may be referred to as an undershoot voltage.
Wherein the larger the overshoot amplitude of the overshoot voltage, the larger the first number; conversely, the smaller the overshoot amplitude, the smaller the first quantity. Similarly, the larger the undershoot amplitude of the undershoot voltage is, the larger the second number is; conversely, the smaller the undershoot amplitude, the smaller the second number.
In a possible embodiment, a corresponding relationship between the magnitude of the overshoot voltage and the number of the power supply branches that are turned off may be preset, and further, when the output voltage is greater than the first threshold, the number of the power supply branches that need to be turned off for the current overshoot voltage may be determined according to the corresponding relationship.
In another possible implementation manner, the first number of the power supply branches determined to be turned off in response to the overshoot according to the magnitude of the current output voltage may specifically be: determining the size of a first difference value between the current output voltage and a preset reference voltage according to the size of the current output voltage; a first number of supply branches to be switched off in response to the overshoot is determined depending on the magnitude of the first difference. Similarly, the corresponding relationship between the magnitude of the first difference and the number of the power supply branches to be turned off may be preset, and then, when the output voltage is greater than the first threshold, the number of the power supply branches to be turned off according to the current overshoot voltage may be determined according to the corresponding relationship.
In the embodiment of determining the second number, the corresponding relationship between the magnitude of the undershoot voltage and the number of conducting power supply branches may be preset, and further, when the output voltage is smaller than the second threshold, the number of power supply branches required to be conducted by the current undershoot voltage may be determined according to the corresponding relationship.
Or determining the size of a second difference value between the current output voltage and a preset reference voltage according to the size of the current output voltage; a second number of supply branches to conduct in response to the undershoot is determined based on a magnitude of the second difference. Similarly, the corresponding relationship between the magnitude of the second difference and the number of the conducting power supply branches may be preset, and then, when the output voltage is smaller than the second threshold, the number of the power supply branches required to be conducted by the current undershoot voltage may be determined according to the corresponding relationship. Optionally, a correspondence between the magnitude of the first difference and the number of the turned-off power supply branches may be the same as a correspondence between the magnitude of the second difference and the number of the turned-on power supply branches, and on this basis, when the same correspondence is adopted based on a deviation between the voltage amplitude and the reference voltage, the complexity of circuit logic may be reduced, and the processing efficiency may be improved.
Correspondingly, the switch regulation module may be configured to: when receiving the overshoot signal and the information of the first quantity, determining the power supply branch to be switched off according to the first quantity and the currently switched-on power supply branch, and adjusting the first control signal of the power supply branch to be switched off from the switching-on level to the switching-off level; and when the information of the undershoot signals and the second quantity is received, determining the power supply branch to be switched on according to the second quantity and the currently switched-off power supply branch, and adjusting the first control signal of the power supply branch to be switched on from the switching-off level to the switching-on level.
In a possible implementation manner, when the overshoot signal and the first number of information are received, the switch regulation and control module may determine, through a first preset logic, the power supply branches to be turned off among the power supply branches that are currently turned on, and the number of the power supply branches to be turned off may be less than or equal to the first number. For example, when the number of the current power supply branches available for responding to the overshoot is greater than or equal to the first number, any first number of the current power supply branches may be used as the power supply branches to be turned off, and at this time, the number of the current power supply branches to be turned off is equal to the first number; when the current available power supply branches for responding to the overshoot are smaller than the first number, the remaining power supply branches that are turned on may be turned off on the basis of ensuring that the number of power supply branches that are turned on in the output circuit is equal to the set normally-on number, and at this time, the number of power supply branches to be turned off may be smaller than the first number.
Similarly, when the undershoot signal and the information of the second number are received, the switch regulation and control module may determine, through a second preset logic, the power supply branches to be turned on among the power supply branches that are currently turned off, and the number of the power supply branches to be turned on may be less than or equal to the second number. For example, when the number of power supply branches currently available for responding to undershoot is greater than or equal to the second number, any second number of power supply branches may be used as power supply branches to be turned on, and at this time, the number of power supply branches to be turned on is equal to the second number; when the current power supply branches available for responding to the undershoot are smaller than the second number, all the power supply branches that are turned off may be used as power supply branches to be turned on, and at this time, the number of power supply branches to be turned on may be smaller than the second number.
The present embodiment does not limit the strategy for determining the specific power supply branch among the power supply branches available for response, and for example, a randomly determined manner may be adopted, or a sequentially determined manner may also be adopted.
Optionally, the output circuit is further configured to:
at least one power supply branch is turned on during power-up of the LDO circuit.
In one possible embodiment, when the LDO circuit is powered on, at least one power supply branch may be turned on to provide a base voltage for the output voltage, so as to implement a basic low dropout linear regulator function. Optionally, the number of power supply branches turned on at power-on may be greater than or equal to the number of power supply branches turned on normally.
Alternatively, referring to the LDO circuit schematic shown in fig. 5, when multiple power supply branches are employed to conduct during power-up, the output circuit may be configured to:
during the power-on period of the LDO circuit, the plurality of power supply branches are conducted in sequence.
In a possible embodiment, in the case that a plurality of power supply branches are used, during power-up of the LDO circuit, the plurality of power supply branches may be controlled to be sequentially turned on to reduce voltage overshoot during power-up. Because the amplitude of the output voltage is related to the driving power, when the power supply branches are sequentially conducted, the instantaneous power conducted every time is small, the overshoot amplitude of the output voltage is also small, compared with the technical scheme of conducting a plurality of power supply branches simultaneously, the overshoot amplitude of the output voltage is greatly reduced, the situation that the power supply voltage of the system is pulled down due to the fact that the overshoot amplitude of the output voltage of the LDO circuit is too large can be avoided, and the stability of the system is improved.
Optionally, referring to the LDO circuit schematic shown in fig. 6, the LDO circuit may further include a second control module, and the second control module may be configured to generate a second control signal for the power supply branch during power-up of the LDO circuit, where the second control signal includes an off level for turning off the power supply branch and an on level for turning on the power supply branch. The turn-off level and the turn-on level are the same as the first control signal.
The second control module may be configured to:
during power-up of the LDO circuit, the second control signal of the at least one power supply branch is adjusted from an off level to an on level.
In one possible embodiment, the second control signal output by the second control module may be switched into the corresponding power supply branch. The second control signal of each power supply branch may be at an off level before the LDO circuit is powered on.
Whether the LDO circuit is powered on or not can be controlled through the enabling signal. When the enable signal is enabled, the second control module may adjust the second control signal of the power supply branch that is turned on during power-up from the off level to the on level. Furthermore, the power supply branch can be switched on when the second control signal jumps from the off level to the on level, so as to provide the base voltage for the output voltage.
Optionally, the second control module may be configured to adjust the second control signals of the plurality of power supply branches from the off level to the on level sequentially during the power-up of the LDO circuit, corresponding to a case of controlling the plurality of power supply branches to be turned on at the power-up time.
In one possible embodiment, the second control module may adjust the second control signals of the plurality of power supply branches from the off level to the on level at different times. Furthermore, the plurality of power supply branches can be controlled to be conducted at different moments, namely, sequentially conducted.
Optionally, for each time instant when the second control signal transitions from the off level to the on level, the time interval of each two adjacent time instants is the same. On the basis, the overshoot amplitude of the output voltage of the LDO circuit during the power-on period can be stably adjusted, and the stability of the system is further improved.
The first control module and the second control module may be the same or different. When the first control module and the second control module are the same, the first control signal and the second control signal of one power supply branch may also be the same control signal. When the first control module and the second control module are different, a second control signal output by the second control module can be selected to control each power supply branch circuit during the power-on period of the LDO circuit; after that, the first control signal output by the first control module can be selected to control each power supply branch.
The embodiment of the application can obtain the following beneficial effects:
(1) the LDO circuit can include output circuit, and output circuit includes a plurality of power supply branch road, can produce when undershoot at output voltage, can realize the quick response to undershoot through switching on the power supply branch road. And when the output voltage generates overshoot, the quick response to the overshoot can be realized by switching off the power supply branch circuit.
(2) When the response is overshot, the plurality of power supply branches are controlled to be sequentially turned off, and/or when the response is undershoot, the plurality of power supply branches are controlled to be sequentially turned on, so that the transient power consumption of the LDO circuit can be reduced.
(3) During the power-on period of the LDO circuit, the plurality of power supply branches can be controlled to be sequentially conducted, the overshoot amplitude of the output voltage is greatly reduced, the problem that the system power supply voltage is pulled down due to the fact that the overshoot amplitude of the output voltage of the LDO circuit is too large can be avoided, and the stability of the system is improved.
The embodiment of the application further provides an LDO circuit, which can be integrated in a chip or arranged in an electronic device. Referring to the schematic diagram of the LDO circuit shown in fig. 7, the difference from the LDO circuit provided in the above embodiment is that the supply branch of the above embodiment can be flexibly used for responding to overshoot or undershoot, and the present embodiment divides the supply branch into a first supply branch for responding to overshoot, and/or a second supply branch for responding to undershoot, and/or a third supply branch which is normally on.
Optionally, the output circuit may be configured to:
when the output voltage of the LDO circuit overshoots, at least one first power supply branch which is conducted is turned off; and/or
And when the output voltage of the LDO circuit undershoots, at least one second power supply branch which is switched off is switched on.
In a possible implementation manner, each power supply branch in the output circuit may be configured as the first power supply branch, the second power supply branch, or the third power supply branch. The first power supply branch is used for responding to overshoot, the second power supply branch is used for responding to undershoot, and the third power supply branch is a normally-on power supply branch. When the LDO circuit is powered on, the initial state of the third power supply branch may be controlled to be a conducting state. When the first power supply branch circuit exists in the output circuit, the initial state of the first power supply branch circuit can be controlled to be a conducting state; when the second power supply branch exists in the output circuit, the initial state of the second power supply branch can be controlled to be an off state.
When the load current of the LDO circuit is suddenly changed and the load is switched from heavy load to light load, the output voltage of the LDO circuit is suddenly changed, and overshoot is generated. At this time, the first power supply branch in the on state can be turned off, and the voltage provided to the output voltage is instantaneously reduced, so that the overshoot output voltage is pulled down, and the output voltage of the LDO circuit is promoted to be quickly restored to a stable value.
When the load current of the LDO circuit is suddenly changed from light load to heavy load, the output voltage of the LDO circuit is suddenly changed along with the sudden change, and undershoot is generated. At this time, the second power supply branch in the off state can be turned on, and the voltage provided to the output voltage is instantaneously increased, so that the undershoot output voltage is pulled high, and the output voltage of the LDO circuit is promoted to be restored to a stable value.
Optionally, when the output circuit includes a plurality of first power supply branches, the output circuit may be configured to sequentially turn off the plurality of turned-on first power supply branches when an output voltage of the LDO circuit overshoots; and/or
When the output circuit includes a plurality of second power supply branches, the output circuit may be configured to sequentially turn on the plurality of second power supply branches that are turned off when an undershoot occurs in the output voltage of the LDO circuit.
Optionally, corresponding to the technical solution that the LDO circuit includes a first control module, the first control module may be configured to generate a first control signal of the first power supply branch and/or the second power supply branch, and the first control module may be configured to:
when the output voltage of the LDO circuit overshoots, adjusting a first control signal of at least one first power supply branch circuit from a conducting level to a switching-off level; and/or
When the output voltage of the LDO circuit undershoots, the first control signal of at least one second power supply branch circuit is adjusted from the turn-off level to the turn-on level.
Optionally, when there are a plurality of first power supply branches and/or a plurality of second power supply branches, the first control module may be configured to:
when the output voltage of the LDO circuit overshoots, the first control signals of the first power supply branches are sequentially adjusted from a conducting level to a switching-off level; and/or
When the output voltage of the LDO circuit undershoots, the first control signals of the second power supply branches are sequentially adjusted from the turn-off level to the turn-on level.
Optionally, the first control module includes an output voltage detection module and a switch regulation module:
the output voltage detection module can be configured to output an overshoot signal when the output voltage overshoots and transmit the overshoot signal to the switch regulation module; when the output voltage generates undershoot, outputting an undershoot signal and transmitting the undershoot signal to the switch regulation and control module;
the switching regulation module may be configured to adjust the first control signal of the at least one first power supply branch from an on level to an off level when the overshoot signal is received, and adjust the first control signal of the at least one second power supply branch from the off level to the on level when the undershoot signal is received.
Optionally, when a third power supply branch is present in the output circuit, the output circuit is further configured to:
during power-up of the LDO circuit, the first and third power supply branches are turned on.
Preferably, the output circuit may be configured to:
during power-up of the LDO circuit, each first power supply branch and each third power supply branch are respectively turned on.
In the preferred scheme, the first power supply branch and the third power supply branch are connected after the LDO circuit is powered on, and meanwhile, the power supply branches are sequentially connected during the power-on period, so that the situation that the power supply voltage of the system is pulled down due to too large overshoot amplitude of the output voltage of the LDO circuit is avoided, and the stability of the system is improved.
When the third power supply branch exists in the output circuit, the third power supply branch can be kept on after the LDO circuit is powered on and is not turned off due to overshoot or undershoot of the output voltage.
Optionally, corresponding to the technical solution that the LDO circuit includes the second control module, the second control module may be configured to generate the second control signals of the first power supply branch and the third power supply branch during power-up of the LDO circuit. The second control module may be configured to:
during power-up of the LDO circuit, the second control signals of the first and third power supply branches are adjusted from an off level to an on level.
Optionally, the second control module may be configured to:
during power-up of the LDO circuit, the plurality of second control signals are sequentially adjusted from an off level to an on level.
This alternative embodiment can be seen from the description of the second control module with reference to the above-described embodiment.
In another alternative, the second control module may be configured to generate the second control signal for the third power supply branch, and the first control module and the second control module may be configured to:
during the power-on period of the LDO circuit, the first control signal of the first power supply branch and the second control signal of the third power supply branch are used as target control signals, and the target control signals are sequentially adjusted from the turn-off level to the turn-on level.
In a possible implementation manner, the first control signal output by the first control module may access the corresponding first power supply branch, and the second control signal output by the second control module may access the corresponding third power supply branch. During the power-on period of the LDO circuit, the control signals output by the first control module and the second control module may cooperate with each other, so that the control signals of each first power supply branch and each third power supply branch are respectively adjusted from the turn-off level to the turn-on level, that is, each first power supply branch and each third power supply branch are respectively turned on.
The first power supply branch is turned off when the response overshoot occurs, and the first power supply branch can be reset to an initial state, namely, a conducting state, until the LDO circuit is powered on again. Similarly, the second power supply branch is turned on in response to the undershoot, and the second power supply branch may be reset to the initial state, i.e., the off state, until the LDO circuit is powered on again.
The same processing of the present embodiment and the above embodiments can refer to the description of the above embodiments, and the description of the present embodiment is omitted.
The embodiment of the application can obtain the following beneficial effects:
(1) the output circuit of the LDO circuit can be specifically provided with a first power supply branch circuit for responding to overshoot and/or a second power supply branch circuit for responding to undershoot, when the output voltage generates overshoot, the first power supply branch circuit is turned off to realize quick response to the overshoot, and when the output voltage generates undershoot, the second power supply branch circuit is turned on to realize quick response to the undershoot. In addition, the output circuit can be provided with a normally-open third power supply branch circuit, so that the basic operation of the LDO circuit is ensured.
(2) When the response overshoot is responded, the plurality of first power supply branches are controlled to be sequentially turned off, and/or when the response undershoot is responded, the plurality of second power supply branches are controlled to be sequentially turned on, so that the transient power consumption of the LDO circuit can be reduced.
(3) During the power-on period of the LDO circuit, the plurality of power supply branches can be controlled to be sequentially conducted, the overshoot amplitude of the output voltage is greatly reduced, the problem that the system power supply voltage is pulled down due to the fact that the overshoot amplitude of the output voltage of the LDO circuit is too large can be avoided, and the stability of the system is improved.
The LDO circuit provided in the present application will be described with reference to a specific circuit structure, but is not limited to the specific circuit structure provided in this embodiment. The LDO circuit provided by this embodiment can implement transient response adjustment of 1bit or multiple bits, that is, control one or more power supply branches to implement transient response.
Referring to the schematic diagram of the LDO circuit shown in fig. 8, the LDO circuit may include an error amplifier AMP, an output circuit, a load resistor-capacitor, a feedback resistor string, a power-up stage start-up control circuit, an output voltage detection circuit, and a transient response switch regulation circuit, where the output circuit includes a plurality of branches, each branch being composed of a MOS transistor and a switch connected in series with the MOS transistor. The plurality of branches can be divided into a power-on starting branch group, an overshoot regulation branch group and a undershoot regulation branch group.
The power-on starting branch group corresponds to the third power supply branch and comprises 3 parallel MOS transistors MP1, MP2 and MP3, each MOS transistor is adapted to a switch to form 3 third power supply branches, and the control is performed based on S1P, S2P and S3P signals (corresponding to the second control signal of the third power supply branch) respectively.
The overshoot adjustment branch group corresponds to the first power supply branch and comprises 2 MOS tubes MP4 and MP5 which are connected in parallel, each MOS tube is matched with a switch to form 2 first power supply branches, and the first power supply branches are controlled based on S4P and S5P signals (corresponding to first control signals of the first power supply branch).
The down-stroke adjusting branch group corresponds to the second power supply branch and comprises 2 MOS tubes MP6 and MP7 which are connected in parallel, each MOS tube is matched with a switch to form 2 second power supply branches, and the second power supply branches are controlled based on S6P and S7P signals (corresponding to first control signals of the second power supply branch).
First ends of the MOS tubes MP1, MP2, MP3, MP4, MP5, MP6 and MP7 are all used for being connected with a power supply voltage VDD, second ends of the MOS tubes are all connected with an output end of the LDO circuit, and third ends (namely control ends) of the MOS tubes are all connected with an output end of the error amplifier AMP.
The load resistor capacitor includes a load resistor ESR and a load capacitor Cload. One end of the load resistor ESR is connected with the output end of the LDO circuit, and the other end of the load resistor ESR is connected with the load capacitor Cload. One end of the load capacitor Cload is connected to the load resistor ESR, and the other end is grounded.
The feedback resistor string comprises resistors R1 and R2 which are connected in series and respectively correspond to the first feedback resistor unit and the second feedback resistor unit. One end of the resistor R1 is connected with the output end of the LDO circuit, and the other end is connected with the resistor R2. One end of the resistor R2 is connected to the resistor R1, and the other end is grounded.
The error amplifier AMP corresponds to the amplifying circuit, and has an inverting input terminal for receiving the reference voltage VREF, a non-inverting input terminal for receiving the feedback voltage VFB, and output terminals connected to control terminals of the MOS transistors MP1, MP2, MP3, MP4, MP5, MP6, and MP7, respectively. The feedback voltage VFB is a voltage between the resistors R1 and R2. The error amplifier AMP is driven based on the enable signal ENN, and operates normally when the enable signal ENN is enabled.
The power-on stage starting control circuit is used for receiving an enable signal ENN and a band gap reference circuit signal BGR _ OK and outputting signals S1P, S2P and S3P.
The output voltage detection circuit corresponds to the output voltage detection module and is controlled based on signals S1P, S2P and S3P, the input end of the output voltage detection circuit is connected with the output end of the LDO circuit, and the output end of the output voltage detection circuit is connected with the transient response switch regulation and control circuit.
The transient response switch regulation and control circuit corresponds to the switch regulation and control module, the input end of the transient response switch regulation and control circuit is connected with the output voltage detection circuit, and signals S4P, S5P, S6P and S7P are output.
The operation principle of the LDO circuit for realizing multi-stage start-up will be described with reference to the timing diagram shown in fig. 9.
When the enable signal ENN jumps from a high level to a low level, the enable signal ENN is enabled, and the LDO circuit starts to be powered on. At this time, the BGR _ OK signal may correspondingly transition from a low level to a high level. The power-on stage starting control circuit delays the BGR _ OK signal (a transition signal from low to high) by t1 in sequence under the control of an enable signal ENN to obtain signals S1P, S2P and S3P: the timing at which the S1P signal jumps from low to high is the same as the BGR _ OK signal (there may be a certain time interval), and the timing at which the S2P signal jumps from low to high is delayed by the S1P signal delay time t1, and the timing at which the S3P signal jumps from low to high is delayed by the S2P signal delay time t 1.
In fig. 9, a solid line in the schematic diagram of the output voltage LDO _ VOUT indicates a voltage change of the output voltage LDO _ VOUT when MP1, MP2, and MP3 are sequentially turned on, and a dotted line indicates a voltage change of the output voltage LDO _ VOUT when MP1, MP2, and MP3 are simultaneously turned on. It can be seen that under the control of the signals S1P, S2P, and S3P, the MP1, MP2, and MP3 are respectively connected to the circuits, so that the overshoot of the output voltage LDO _ VOUT of the LDO circuit during power-up is greatly reduced compared with the overshoot of the output voltage LDO _ VOUT of the LDO circuit when the MP1, MP2, and MP3 are turned on simultaneously, and therefore the power supply voltage is prevented from being pulled down due to too large overshoot of the output voltage LDO _ VOUT of the LDO circuit, and the stability of the system is improved.
The operation principle of the LDO circuit to realize the transient response regulation of 1bit will be described with reference to the timing diagram shown in fig. 10.
After the output voltage LDO _ VOUT is stabilized, when the load current I _ load suddenly changes, the heavy load Imax is switched to the light load Imin, and the output voltage of the LDO suddenly changes along with the sudden change, so that overshoot is generated. At this time, the output voltage detection circuit outputs an undershoot signal (corresponding to the overshoot signal described above) under the control of the S1P, S2P, and S3P signals. The negative pulse signal acts on the transient response switch regulating circuit, so that the transient response switch regulating circuit generates a negative pulse signal S4P or S5P (namely a 1-bit control signal) to control the turn-off of the MOS transistor MP4 or MP5 in the overshoot regulating branch group, thereby increasing the bandwidth of the error amplifier to accelerate the loop response and further quickly recovering the output voltage of the LDO to a stable value.
When the load current I _ load changes abruptly, the light-load Imin is switched to the heavy-load Imax, and the output voltage of the LDO changes abruptly, so that an undershoot is generated. At this time, the output voltage detection circuit outputs one positive pulse signal (corresponding to the undershoot signal described above) under the control of the S1P, S2P, and S3P signals. The positive pulse signal acts on the transient response switch regulating circuit, so that the transient response switch regulating circuit generates a positive pulse signal S6P or S7P (namely a 1-bit control signal) to control the conduction of the MOS transistor MP6 or MP7 in the down-regulation branch group, thereby increasing the power supply branch and further quickly restoring the output voltage of the LDO to a stable value.
In fig. 10, a solid line in the schematic diagram of the output voltage LDO _ VOUT indicates a voltage change of the output voltage LDO _ VOUT when transient response regulation is performed according to the present application, and a dotted line indicates a voltage change of the output voltage LDO _ VOUT when transient response regulation is not performed. It can be seen that, when the method is adopted, the time for the output voltage LDO _ VOUT to recover to the stable value is shortened, and the transient response performance of the LDO circuit is improved.
The operation principle of the LDO circuit for implementing multi-bit transient response regulation will be described with reference to the timing diagram shown in fig. 11.
After the output voltage LDO _ VOUT is stabilized, when the load current I _ load suddenly changes, the heavy load Imax is switched to the light load Imin, and the output voltage of the LDO suddenly changes along with the sudden change, so that overshoot is generated. At this time, the output voltage detection circuit outputs an undershoot signal (corresponding to the overshoot signal described above) under the control of the S1P, S2P, and S3P signals. The negative pulse signal acts on the transient response switch regulating circuit, so that the transient response switch regulating circuit generates two negative pulse signals S4P and S5P (namely 2-bit control signals) according to different threshold voltages, and controls MOS (metal oxide semiconductor) tubes MP4 and MP5 in the overshoot regulating branch group to be turned off step by step, thereby increasing the bandwidth of the error amplifier to accelerate loop response and further quickly restoring the output voltage of the LDO to a stable value.
When the load current I _ load changes suddenly, the light load Imin is switched to the heavy load Imax, and the output voltage of the LDO changes suddenly along with the light load Imin, so that an undershoot is generated. At this time, the output voltage detection circuit follows a positive pulse signal (corresponding to the undershoot signal described above) under the control of the S1P, S2P, and S3P signals. The positive pulse signal acts on the transient response switch regulating circuit, so that the transient response switch regulating circuit generates two positive pulse signals S6P and S7P (namely 2-bit control signals) according to different threshold voltages, and the MOS (metal oxide semiconductor) tubes MP6 and MP7 in the down-pulse regulating branch set are controlled to be conducted step by step, so that power supply branches are added, and the output voltage of the LDO is quickly recovered to a stable value.
In fig. 11, a solid line in the schematic diagram of the output voltage LDO _ VOUT indicates a voltage change of the output voltage LDO _ VOUT when transient response regulation is performed with the stepwise on and the stepwise off, and a dotted line indicates a voltage change of the output voltage LDO _ VOUT when transient response regulation is not performed with the stepwise on and the stepwise off. It can be seen that when the step-by-step connection and step-by-step disconnection are adopted, the multi-position fine regulation can be carried out on the overshoot or undershoot amplitude of the output voltage LDO _ VOUT, the number of the connected MOS tubes can be regulated according to the real-time change of the load, and therefore the LDO has the effect of fast response to the output voltage of the LDO, and meanwhile the transient power consumption can be reduced.
In this embodiment, for example, a group of 2 MOS transistors is included, and the corresponding control signal may be 2 bits. When a group includes more than 2 MOS transistors, the corresponding control signal is not limited to 2 bits, and may be any multi-bit.
The embodiment of the application can obtain the following beneficial effects:
(1) the LDO circuit can comprise a first power supply branch circuit used for responding to overshoot and a second power supply branch circuit used for responding to undershoot, when the output voltage generates overshoot, the first power supply branch circuit is turned off to realize fast response to the overshoot, and when the output voltage generates undershoot, the second power supply branch circuit is turned on to realize fast response to the undershoot.
(2) When the response is overshot, the plurality of first power supply branches are controlled to be sequentially turned off, and/or when the response is undershoot, the plurality of second power supply branches are controlled to be sequentially turned on, so that the transient power consumption of the LDO circuit can be reduced.
(3) During the power-on period of the LDO circuit, the third power supply branches can be controlled to be sequentially conducted, the overshoot amplitude of the output voltage is greatly reduced, the situation that the power voltage of the system is pulled down due to the fact that the overshoot amplitude of the output voltage of the LDO circuit is too large can be avoided, and the stability of the system is improved.
The embodiment of the application also provides a control method of the LDO circuit, which can be used for controlling the LDO circuit. Referring to the flowchart of the control method of the LDO circuit shown in fig. 12, the method may be as follows:
step 1201, outputting an output voltage of the LDO circuit based on the output circuit;
and step 1202, when the output voltage of the LDO circuit undershoots, at least one power supply branch which is turned off is turned on.
Optionally, when there are a plurality of switched-off power supply branches, said switching on at least one switched-off power supply branch when an undershoot occurs in an output voltage of the LDO circuit comprises: and when the output voltage of the LDO circuit undershoots, sequentially switching on the plurality of switched-off power supply branches.
Optionally, the method further comprises: and when the output voltage of the LDO circuit is overshot, at least one conducting power supply branch is switched off.
Optionally, when there are a plurality of conducting power supply branches, said turning off at least one conducting power supply branch when an output voltage of the LDO circuit overshoots includes: and when the output voltage of the LDO circuit is overshot, the plurality of conducted power supply branches are sequentially turned off.
Optionally, the LDO circuit further includes a first control module, the first control module is configured to generate a first control signal for the power supply branch, the first control signal includes an off level for turning off the power supply branch and an on level for turning on the power supply branch;
the method further comprises the following steps: when the output voltage of the LDO circuit undershoots, the first control signal of at least one power supply branch circuit is adjusted from a turn-off level to a turn-on level.
Optionally, when there are a plurality of power supply branches that are turned off, the adjusting the first control signal of at least one power supply branch from an off level to an on level when the output voltage of the LDO circuit undershoots includes: when the output voltage of the LDO circuit undershoots, the first control signals of the plurality of power supply branches are sequentially adjusted from the turn-off level to the turn-on level.
Optionally, the method further comprises: when the output voltage of the LDO circuit is overshot, the first control signal of at least one power supply branch is adjusted from a conducting level to a switching-off level.
Optionally, when there are a plurality of conducting power supply branches, the adjusting the first control signal of at least one power supply branch from a conducting level to a turn-off level when the output voltage of the LDO circuit overshoots includes: when the output voltage of the LDO circuit is overshot, the first control signals of the plurality of power supply branches are sequentially adjusted from the on level to the off level.
Optionally, the first control module includes an output voltage detection module and a switch regulation module, and the method further includes:
when the output voltage generates undershoot, controlling the output voltage detection module to output an undershoot signal and transmitting the undershoot signal to the switch regulation and control module;
and when the undershoot signal is received, controlling the switch regulation and control module to regulate the first control signal of at least one power supply branch circuit from a turn-off level to a turn-on level.
Optionally, the method further comprises:
when the output voltage is overshot, controlling the output voltage detection module to output an overshoot signal, and transmitting the overshoot signal to the switch regulation and control module;
and when the overshoot signal is received, controlling the switch regulation and control module to regulate the first control signal of at least one power supply branch circuit from a conducting level to a switching-off level.
Optionally, the method further comprises:
conducting at least one power supply branch during power-up of the LDO circuit.
Optionally, the turning on at least one power supply branch during power-up of the LDO circuit includes:
sequentially turning on a plurality of power supply branches during power-up of the LDO circuit.
Optionally, the LDO circuit further comprises a second control module for generating a second control signal for the power supply branch during power-up of the LDO circuit, the second control signal comprising an off level for turning off the power supply branch and an on level for turning on the power supply branch;
the method further comprises the following steps:
adjusting a second control signal of at least one power supply branch from an off level to an on level during power-up of the LDO circuit.
Optionally, the adjusting the second control signal of the at least one power supply branch from an off level to an on level during the power-up of the LDO circuit includes:
during the power-on of the LDO circuit, the second control signals of the plurality of power supply branches are sequentially adjusted from an off level to an on level.
Optionally, the LDO circuit further comprises an amplifying circuit, a first feedback resistance unit, and a second feedback resistance unit, wherein,
the first input end of the amplifying circuit is used for receiving a reference voltage, the second input end of the amplifying circuit is used for receiving a feedback voltage between the first feedback resistance unit and the second feedback resistance unit, and the output end of the amplifying circuit is connected with the first input end of the output circuit;
the second input end of the output circuit is used for receiving power supply voltage, and the output end of the output circuit is connected with the output end of the LDO circuit;
the first end of the first feedback resistance unit is connected with the output end of the LDO circuit, and the second end of the first feedback resistance unit is connected with the first end of the second feedback resistance unit;
and the second end of the second feedback resistance unit is connected with the ground.
In an embodiment of the present application, the LDO circuit may include an output circuit including a plurality of power supply branches. When the output voltage generates undershoot, the power supply branch circuit is conducted to realize quick response to the undershoot.
The exemplary embodiment of the present application also provides a chip including the LDO circuit provided in the embodiments of the present application. In an embodiment of the present application, the LDO circuit may include an output circuit including a plurality of power supply branches. When the output voltage generates undershoot, the power supply branch is conducted to realize quick response to the undershoot, and the performance and the stability of the chip are improved.
The exemplary embodiment of the present application further provides an electronic device, which includes the LDO circuit provided in the embodiment of the present application. In an embodiment of the present application, the LDO circuit may include an output circuit including a plurality of power supply branches. When the output voltage generates undershoot, the power supply branch is conducted to realize quick response to the undershoot, and the performance and the stability of the electronic equipment are improved.
The LDO circuit, the control method, the chip, and the electronic device provided in the present application are introduced in detail, and specific examples are applied in the present application to explain the principles and embodiments of the present application, and the descriptions of the above embodiments are only used to help understand the method and the core idea of the present application; meanwhile, for a person skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims (18)

1. A low dropout regulator (LDO) circuit, comprising an output circuit comprising a plurality of power supply branches;
the output circuit is configured to: and when the output voltage of the LDO circuit undershoots, at least one switched-off power supply branch is switched on.
2. The LDO circuit of claim 1, wherein the output circuit is configured to:
and when the output voltage of the LDO circuit undershoots, sequentially conducting the plurality of switched-off power supply branches.
3. The LDO circuit of claim 1, wherein the output circuit is further configured to:
and when the output voltage of the LDO circuit is overshot, at least one conducting power supply branch is switched off.
4. The LDO circuit of claim 3, wherein the output circuit is configured to:
and when the output voltage of the LDO circuit overshoots, the plurality of conducted power supply branches are sequentially switched off.
5. The LDO circuit of claim 1, wherein the LDO circuit further comprises a first control module for generating a first control signal for a power supply branch, the first control signal comprising an off level for turning off the power supply branch and an on level for turning on the power supply branch;
the first control module is configured to:
when the output voltage of the LDO circuit undershoots, the first control signal of at least one power supply branch circuit is adjusted from a turn-off level to a turn-on level.
6. The LDO circuit of claim 5, wherein the first control module is configured to:
when the output voltage of the LDO circuit undershoots, the first control signals of the plurality of power supply branches are sequentially adjusted from the turn-off level to the turn-on level.
7. The LDO circuit of claim 5, wherein the first control module is further configured to:
when the output voltage of the LDO circuit is overshot, the first control signal of at least one power supply branch is adjusted from a conducting level to a switching-off level.
8. The LDO circuit of claim 7, wherein the first control module is configured to:
when the output voltage of the LDO circuit is overshot, the first control signals of the plurality of power supply branches are sequentially adjusted from the on level to the off level.
9. The LDO circuit of claim 5, wherein the first control module comprises an output voltage detection module and a switching regulation module;
the output voltage detection module is configured to output an undershoot signal when the output voltage undershoots, and transmit the undershoot signal to the switching regulation and control module;
the switch regulation and control module is configured to adjust the first control signal of at least one power supply branch from an off level to an on level when the undershoot signal is received.
10. The LDO circuit of claim 9, wherein the output voltage detection module is further configured to output an overshoot signal when the output voltage overshoots, and transmit the overshoot signal to the switching regulator module;
the switch regulation module is further configured to adjust the first control signal of the at least one power supply branch from an on level to an off level upon receiving the overshoot signal.
11. The LDO circuit of claim 1, wherein the output circuit is further configured to:
conducting at least one power supply branch during power-up of the LDO circuit.
12. The LDO circuit of claim 11, wherein the output circuit is configured to:
sequentially turning on a plurality of power supply branches during power-up of the LDO circuit.
13. The LDO circuit of claim 11, wherein the LDO circuit further comprises a second control module for generating a second control signal for the power supply branch during power-up of the LDO circuit, the second control signal comprising an off level for turning off the power supply branch and an on level for turning on the power supply branch;
the second control module is configured to:
adjusting a second control signal of at least one power supply branch from an off level to an on level during power-up of the LDO circuit.
14. The LDO circuit of claim 13, wherein the second control module is configured to:
during the power-on of the LDO circuit, the second control signals of the plurality of power supply branches are sequentially adjusted from an off level to an on level.
15. The LDO circuit of claim 1, further comprising an amplification circuit, a first feedback resistance unit, and a second feedback resistance unit, wherein,
the first input end of the amplifying circuit is used for receiving a reference voltage, the second input end of the amplifying circuit is used for receiving a feedback voltage between the first feedback resistance unit and the second feedback resistance unit, and the output end of the amplifying circuit is connected with the first input end of the output circuit;
a second input end of the output circuit is used for receiving power supply voltage, and an output end of the output circuit is connected with an output end of the LDO circuit;
the first end of the first feedback resistance unit is connected with the output end of the LDO circuit, and the second end of the first feedback resistance unit is connected with the first end of the second feedback resistance unit;
and the second end of the second feedback resistance unit is connected with the ground.
16. A method of controlling an LDO circuit, the LDO circuit comprising an output circuit, the output circuit comprising a plurality of power supply branches, the method comprising:
outputting an output voltage of the LDO circuit based on the output circuit;
and when the output voltage of the LDO circuit undershoots, at least one switched-off power supply branch is switched on.
17. A chip comprising an LDO circuit according to at least one of claims 1-15.
18. An electronic device comprising an LDO circuit according to at least one of claims 1-15.
CN202210395751.2A 2022-04-15 2022-04-15 LDO circuit, control method, chip and electronic equipment Pending CN114690828A (en)

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* Cited by examiner, † Cited by third party
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US20030178980A1 (en) * 2002-03-25 2003-09-25 Hubert Biagi Composite loop compensation for low drop-out regulator
US20140084881A1 (en) * 2012-09-25 2014-03-27 Yi-Chun Shih Low dropout regulator with hysteretic control
CN108710399A (en) * 2018-04-25 2018-10-26 电子科技大学 A kind of LDO circuit with high transient response
US20190004552A1 (en) * 2017-07-03 2019-01-03 Macronix International Co., Ltd. Fast transient response voltage regulator with predictive loading
US10216209B1 (en) * 2018-06-11 2019-02-26 SK Hynix Inc. Digital low drop-out regulator and operation method thereof
US20190107856A1 (en) * 2017-10-11 2019-04-11 Hyundai Autron Co., Ltd. Real-time slope control apparatus for voltage regulator and operating method thereof
CN209980116U (en) * 2019-05-10 2020-01-21 深圳市汇春科技股份有限公司 Overshoot elimination circuit and undershoot elimination circuit of low dropout regulator and chip
US20220019253A1 (en) * 2020-07-15 2022-01-20 Semiconductor Components Industries, Llc Adaptable low dropout (ldo) voltage regulator and method therefor

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030178980A1 (en) * 2002-03-25 2003-09-25 Hubert Biagi Composite loop compensation for low drop-out regulator
US20140084881A1 (en) * 2012-09-25 2014-03-27 Yi-Chun Shih Low dropout regulator with hysteretic control
US20190004552A1 (en) * 2017-07-03 2019-01-03 Macronix International Co., Ltd. Fast transient response voltage regulator with predictive loading
US20190107856A1 (en) * 2017-10-11 2019-04-11 Hyundai Autron Co., Ltd. Real-time slope control apparatus for voltage regulator and operating method thereof
CN108710399A (en) * 2018-04-25 2018-10-26 电子科技大学 A kind of LDO circuit with high transient response
US10216209B1 (en) * 2018-06-11 2019-02-26 SK Hynix Inc. Digital low drop-out regulator and operation method thereof
CN209980116U (en) * 2019-05-10 2020-01-21 深圳市汇春科技股份有限公司 Overshoot elimination circuit and undershoot elimination circuit of low dropout regulator and chip
US20220019253A1 (en) * 2020-07-15 2022-01-20 Semiconductor Components Industries, Llc Adaptable low dropout (ldo) voltage regulator and method therefor

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Application publication date: 20220701