CN116560445A - A low-dropout linear voltage regulator with dynamically adjustable output and system on chip - Google Patents

Abstract

The application provides a low dropout linear voltage regulator and a system-on-chip for dynamically regulating output, which comprises a main body circuit and a reference voltage conversion circuit, wherein the main body circuit comprises an error amplifier and an output voltage regulating unit; the first input end of the error amplifier is connected with the output end of the reference voltage conversion circuit, the output end of the error amplifier is connected with the first end of the output voltage regulating unit, the second input end of the error amplifier is connected with the second end of the output voltage regulating unit, the second end of the output voltage regulating unit is also used for being connected with a rear-stage load circuit, and the third end of the output voltage regulating unit is connected with the first driving power supply; the reference voltage conversion circuit is used for outputting corresponding reference voltage based on the voltage output demand instruction. The reference voltage conversion circuit can generate different reference voltages according to the voltage output demand instruction, so that different expected output voltages are obtained, and the aim of dynamically adjusting the output voltages is fulfilled.

Description

A low-dropout linear voltage regulator with dynamically adjustable output and system on chip

technical field

The application relates to the field of chips, in particular, to a low-dropout linear voltage regulator and a system on a chip for dynamically adjusting output.

Background technique

Low-dropout regulator (English: Low-dropout regulator, LDO), also known as low-dropout linear regulator, is a kind of linear DC regulator, which can be used to convert high input voltage into low voltage for future The stage load circuit module supplies power, for example, it can be used for voltage regulation in a system on chip (SOC for short). LDO is widely used in high-performance power modules because of its low power consumption, high power supply rejection capability, and small area.

With the development of science and technology, the integration requirements of SOC are getting higher and higher, and personnel in the field are required to optimize layout resource allocation. Specifically, how to optimize the layout based on the LDO so as to reduce the volume of the product has become a difficult problem that those skilled in the art are concerned about.

Contents of the invention

The purpose of the present application is to provide a low-dropout linear voltage regulator and a system-on-chip for dynamically adjusting output, so as to at least partly solve the above-mentioned problems.

In order to achieve the above purpose, the technical solution adopted in the embodiment of the present application is as follows:

In the first aspect, an embodiment of the present application provides a low-dropout linear regulator that dynamically adjusts output. The low-dropout linear regulator includes a main circuit and a reference voltage conversion circuit. The main circuit includes an error amplifier and an output voltage regulator. unit;

The first input end of the error amplifier is connected to the output end of the reference voltage conversion circuit, the output of the error amplifier is single-connected to the first end of the output voltage adjustment unit, and the second input end of the error amplifier connected to the second end of the output voltage adjustment unit, the second end of the output voltage adjustment unit is also used to connect to the subsequent load circuit, and the third end of the output voltage adjustment unit is connected to the first driving power supply;

The reference voltage conversion circuit is used to output a corresponding reference voltage based on a voltage output demand command.

Optionally, the error amplifier is configured to output a first control signal based on a comparison result between the output voltage of the output voltage adjustment unit and the reference voltage when an enable signal is received;

The output voltage adjusting unit is used for adjusting the output voltage based on the first control signal.

Optionally, the reference voltage conversion circuit includes a management unit and a voltage division unit, the management unit is connected to the control terminal of the voltage division unit, the first terminal of the voltage division unit is connected to the second driving power supply, and the The second terminal of the voltage dividing unit is grounded, and the output terminal of the voltage dividing unit is used as the output terminal of the reference voltage conversion circuit and connected to the first input terminal of the error amplifier;

The management unit is configured to send a second control signal to the voltage dividing unit according to the voltage output demand command;

The voltage dividing unit is configured to output a corresponding reference voltage after receiving the second control signal.

Optionally, the voltage dividing unit includes n voltage dividing resistors and n-1 switching tubes, where n is greater than or equal to 3;

The n voltage dividing resistors are connected in series in sequence, and n-1 connecting terminals are drawn between adjacent resistors;

Each connection terminal is respectively connected to the first pole of the corresponding switch tube, the second poles of the n-1 switch tubes are the control terminals of the voltage dividing unit, connected to the management unit, the n- The third pole of one switch tube is connected to the output end of the voltage dividing unit.

Optionally, the second control signal includes a sub-control signal corresponding to each switch tube, the management unit is a decoder, the input end of the decoder is used to receive the voltage output demand instruction, and the decoder The n-1 output terminals of the n-1 switch tubes are connected in one-to-one correspondence with the second poles of the n-1 switch tubes;

The decoder is used to generate n-1 sub-control signals according to the voltage output demand command, and send the n-1 sub-control signals to the second poles of the corresponding switching tubes respectively, so as to adjust the pass-through of the corresponding switching tubes. off state.

Optionally, at the same time, at most one switch tube is allowed to be in a conduction state.

Optionally, the switch tube is a PMOS tube, the source of the PMOS tube is used as the first pole of the switch tube, the gate of the PMOS tube is used as the second pole of the switch tube, and the PMOS tube The drain of the switch tube is used as the third pole.

Optionally, the output voltage adjustment unit includes a PMOS transistor or a plurality of parallel-connected PMOS transistors;

Alternatively, the output voltage adjustment unit includes one NMOS transistor or multiple NMOS transistors connected in parallel.

Optionally, the inverting input terminal of the error amplifier is connected to the output terminal of the reference voltage conversion circuit as its first input terminal, and the non-inverting input terminal of the error amplifier is connected to the output terminal as its second input terminal. The second terminal of the voltage regulation unit.

In a second aspect, an embodiment of the present application provides a system on chip, including: the above-mentioned low dropout linear voltage regulator.

Compared with the prior art, the embodiment of the present application provides a dynamically adjustable low-dropout linear regulator and system-on-a-chip, including a main circuit and a reference voltage conversion circuit, the main circuit includes an error amplifier and an output voltage adjustment unit; the error The first input end of the amplifier is connected to the output end of the reference voltage conversion circuit, the output of the error amplifier is connected to the first end of the output voltage adjustment unit, and the second input end of the error amplifier is connected to the second end of the output voltage adjustment unit, The second end of the output voltage adjustment unit is also used to connect to the subsequent load circuit, and the third end of the output voltage adjustment unit is connected to the first drive power supply; the reference voltage conversion circuit is used to output the corresponding reference voltage based on the voltage output demand command. The reference voltage conversion circuit can generate different reference voltages according to the voltage output demand command, so as to obtain different expected output voltages and achieve the purpose of dynamically adjusting the output voltage.

In order to make the above-mentioned purpose, features and advantages of the present application more comprehensible, preferred embodiments will be described in detail below together with the accompanying drawings.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the accompanying drawings that are required in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and thus It should be regarded as a limitation on the scope, and those skilled in the art can also obtain other related drawings based on these drawings without creative work.

FIG. 1 is a schematic structural diagram of a low dropout line voltage regulator provided in an embodiment of the present application;

FIG. 2 is a schematic structural diagram of a reference voltage conversion circuit provided in an embodiment of the present application;

FIG. 3 is a schematic structural diagram of a voltage dividing unit provided in an embodiment of the present application;

FIG. 4 is a schematic diagram of a simulation result of a low-dropout linear regulator for dynamically adjusting an output provided by an embodiment of the present application.

In the figure: 10-main circuit; 20-reference voltage conversion circuit; 30-post load circuit; 101-error amplifier; 102-voltage adjustment unit; 103-compensation network; 104-bias circuit; 105-bandgap output buffer device; 201-management unit; 202-voltage dividing unit.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, 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. Obviously, the described embodiments It is a part of the embodiments of this application, not all of them. The components of the embodiments of the application generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations.

Accordingly, the following detailed description of the embodiments of the application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the application. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of this application.

It should be noted that like numerals and letters denote similar items in the following figures, therefore, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures. Meanwhile, in the description of the present application, the terms "first", "second" and the like are only used to distinguish descriptions, and cannot be understood as indicating or implying relative importance.

It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is a relationship between these entities or operations. There is no such actual relationship or order between them. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer" etc. is based on the orientation or positional relationship shown in the drawings, or the The usual orientation or positional relationship of the application product when used is only for the convenience of describing the application and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, therefore It should not be construed as a limitation of the application.

In the description of this application, it should also be noted that, unless otherwise clearly stipulated and limited, the terms "setting" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, or Integral connection; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in this application in specific situations.

Some implementations of the present application will be described in detail below in conjunction with the accompanying drawings. In the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.

Please refer to FIG. 1 , which is a schematic structural diagram of a low dropout line voltage regulator provided by an embodiment of the present application. As shown in FIG. 1 , the low dropout linear regulator for dynamically adjusting output includes a main circuit 10 and a reference voltage conversion circuit 20 , and the main circuit 10 includes an error amplifier 101 and an output voltage adjustment unit 102 .

The first input end of the error amplifier 101 is connected to the output end of the reference voltage conversion circuit 20, the output end of the error amplifier 101 is connected to the first end of the output voltage adjustment unit 102, and the second input end of the error amplifier 101 is connected to the output voltage adjustment unit. The second end of the unit 102, the second end of the output voltage adjustment unit 102 is also used to connect the subsequent load circuit 30, and the third end of the output voltage adjustment unit 102 is connected to the first driving power supply VDD1;

The reference voltage conversion circuit 20 is used for outputting a corresponding reference voltage based on the voltage output demand instruction.

It should be understood that the voltage output demand command corresponds to the demand voltage of the subsequent load circuit 30 that is currently connected to the output voltage adjustment unit 102 , and the demand voltage may be equal to the reference voltage.

It is assumed that the output voltage adjustment unit 102 includes a PMOS transistor or a plurality of parallel-connected PMOS transistors. In order to provide a stable output and a larger load current, the output voltage regulation unit 102 usually uses a larger number of output transistors (such as MP transistors). It should be understood that the error amplifier 101 performs a voltage comparison between the input reference voltage Vref and the output voltage feedback signal of the output voltage adjustment unit 102, and if the output voltage feedback signal is higher than Vref, the error amplifier 101 will output a gate voltage that inhibits the opening of the MP, Therefore, the output voltage is pulled down; if the output voltage feedback signal is lower than Vref, the error amplifier 101 outputs a gate voltage that boosts MP to turn on, thereby pulling up the output voltage. Therefore, the input reference voltage Vref has an important influence on the output voltage of the LDO. If the first input terminal of the error amplifier 101 is connected to an external reference voltage source, the external reference voltage source provides a fixed input reference voltage Vref, thereby obtaining a fixed output voltage. When the LDO is required to provide multiple different voltages externally, that is, the output voltage of the LDO needs to be adjustable, the fixed input reference voltage Vref will not be able to meet the need for an adjustable output voltage.

In the scheme of this application, the reference voltage conversion circuit 20 can convert the fixed voltage provided by the reference voltage source, thereby outputting the reference voltage Vref of different gears, and realizing the LDO circuit design with adjustable reference input voltage and output voltage. The circuit design of the adjustable input reference voltage Vref, so that different Vref can be generated according to the input of the gear setting, so as to obtain the desired different output voltages, and realize the purpose of dynamically adjusting the output voltage.

In summary, the embodiment of the present application provides a low-dropout linear regulator that dynamically adjusts the output, including a main circuit and a reference voltage conversion circuit, the main circuit includes an error amplifier and an output voltage adjustment unit; the first input of the error amplifier terminal is connected to the output terminal of the reference voltage conversion circuit, the output of the error amplifier is single-connected to the first terminal of the output voltage regulation unit, the second input terminal of the error amplifier is connected to the second terminal of the output voltage regulation unit, and the output voltage regulation unit’s The second terminal is also used to connect to the subsequent load circuit, and the third terminal of the output voltage adjustment unit is connected to the first drive power supply; the reference voltage conversion circuit is used to output the corresponding reference voltage based on the voltage output demand command. The reference voltage conversion circuit can generate different reference voltages according to the voltage output demand command, so as to obtain different expected output voltages and achieve the purpose of dynamically adjusting the output voltage.

Optionally, the error amplifier 101 is configured to output a first control signal based on a comparison result between the output voltage of the output voltage adjustment unit 102 and the reference voltage when the enable signal is received;

The output voltage adjusting unit 102 is used for adjusting the output voltage based on the first control signal.

It should be understood that the first control signal may be the voltage signal shown in P1 in FIG. 1 , and the output voltage of the output voltage adjustment unit 102 can be adjusted through the first control signal so that the output voltage is equal to the reference voltage. The reference voltage is adjustable, and the output voltage There are a variety of gear options to meet the voltage requirements of different loads and periods.

Optionally, on the basis of FIG. 1, regarding the structure of the reference voltage conversion circuit 20, the embodiment of the present application also provides a possible implementation, please refer to FIG. 2, which shows the reference voltage provided by the embodiment of the present application Schematic diagram of the conversion circuit.

As shown in FIG. 2 , the reference voltage conversion circuit 20 includes a management unit 201 and a voltage division unit 202, the management unit 201 is connected to the control terminal of the voltage division unit 202, and the first end of the voltage division unit 202 is connected to the second drive power supply VDD2, The second terminal of the voltage dividing unit 202 is grounded VSS, and the output terminal of the voltage dividing unit 202 is used as the output terminal of the reference voltage conversion circuit 20 and connected to the first input terminal of the error amplifier 101 for outputting the reference voltage Vref.

The management unit 201 is configured to send a second control signal (shown as P2 in FIG. 2 ) to the voltage dividing unit 202 according to the voltage output demand command.

The voltage dividing unit 202 is configured to output a corresponding reference voltage after receiving the second control signal.

Please refer to FIG. 3 , which is a schematic structural diagram of a voltage dividing unit provided in an embodiment of the present application. As shown in FIG. 3 , the voltage dividing unit 202 includes n voltage dividing resistors Ri and n-1 switching tubes Qt, n is greater than or equal to 3, i indicates the serial number of the voltage dividing resistor, t indicates the serial number of the switching tube, 1≤i ≤n, 1≤t≤n-1.

Wherein, the switching transistor Qt may be a PMOS transistor, a triode, a field effect transistor and the like.

n voltage dividing resistors Ri are connected in series in sequence, and n-1 connecting terminals are drawn out between adjacent resistors. One end of the series resistor (one end of the voltage dividing resistor R1 ) is connected to the second driving power supply VDD2 , and the other end of the series resistor (one end of the voltage dividing resistor Rn ) is grounded to VSS.

Each connection terminal is respectively connected to the first pole of the corresponding switching tube Qt, and the second poles of the n-1 switching tubes Qt are the control terminals of the voltage dividing unit 202, connected to the management unit 201, and the n-1 switching tubes The third pole of Qt is connected to the output terminal of the voltage dividing unit 202 , and is used as the output terminal of the reference voltage conversion circuit 20 , and is connected to the first input terminal of the error amplifier 101 .

In a possible implementation, the second control signal includes a sub-control signal corresponding to each switch tube Qt, the management unit 201 is a decoder (Decode), the input terminal of the decoder is used to receive the voltage output demand instruction, and the decoder The n-1 output ends (S[1]-S[n-1]) of the n-1 switch tubes Qt (Q1-Qn-1) are connected in one-to-one correspondence.

The decoder is used to generate n-1 sub-control signals according to the voltage output demand command, and send the n-1 sub-control signals to the second pole of the corresponding switching tube Qt to adjust the on-off state of the corresponding switching tube Qt.

Optionally, at the same time, at most one switching transistor Qt is allowed to be in a conducting state.

Optionally, the switch tube Qt is a PMOS tube, the source of the PMOS tube is used as the first pole of the switch tube Qt, and is connected to the connection terminal drawn from the voltage dividing unit 202, and the gate of the PMOS tube is used as the second pole of the switch tube Qt, It is connected to the management unit 201 , and the drain of the PMOS transistor serves as the third pole of the switch transistor Qt, and is connected to the first input end of the error amplifier 101 .

In the scheme of this application, the design architecture of providing adjustable Vref output to the gear position is provided by adding resistor voltage divider to the decoder. Through a series of resistors with the same or different resistance values, N+1 voltage divisions are performed from VDD to VSS. Each voltage division point is controlled by the voltage of Vref[*] through the pmos tube. When S[*] is low potential, The corresponding pmos tube is turned on, and the corresponding divided voltage is sent out to form the selected Vref as the input to participate in the voltage comparison of the error amplifier 101, and the voltage of the output voltage feedback signal is compared with the high and low, and then the power tube is performed according to the comparison result. The turn-on regulation of MP until the output voltage stabilizes at the Vref voltage.

S[0], S[1]...S[m], S[n-1] are generated by the input gear signal D[J:0] through the decoder. For example, the 8-bit D[7:0] input gear signal can generate 128 control gears S[127:0], each time only one S[*] is valid for low voltage, open the corresponding pmos and select vref [*], there are 128 Vref input reference voltages that can be selected and adjusted.

In the LDO design framework with adjustable Vref design, through the voltage division decoding Vref circuit, through the input configuration of the voltage output demand command (adjustable gear input signal D[j:0]), different Vref can be selected, and then input to The error amplifier 101 generates an output voltage Vout of the same voltage. When the Vref voltage becomes adjustable, the voltage of Vout is also adjustable. At this time, the LDO can provide output Vout with different voltages according to the input configuration.

Optionally, the output voltage adjustment unit 102 includes a PMOS transistor or a plurality of parallel-connected PMOS transistors; or, the output voltage adjustment unit 102 includes an NMOS transistor or a plurality of parallel-connected NMOS transistors.

In a possible implementation, the inverting input terminal of the error amplifier 101 is connected to the output terminal of the reference voltage conversion circuit 20 as its first input terminal, and the non-inverting input terminal of the error amplifier 101 is connected to the output terminal as its second input terminal. The second terminal of the voltage regulation unit 102 .

Please continue to refer to FIG. 1. In a possible implementation, the main circuit 10 further includes a bias circuit 104 and a compensation network 103. The bias circuit 104 is connected to the first input terminal of the error amplifier 101 and the first input terminal of the compensation network 103, respectively. terminal connection, the second end of the compensation network 103 is connected to the output end of the error amplifier 101, the third end of the compensation network 103 is connected to the second input end of the error amplifier 101, and the first end of the compensation network 103 is also connected to the error amplifier 101 drive end.

Optionally, the bias circuit 104 is used to provide a bias voltage, and the compensation network 103 is used to perform phase margin compensation.

The main circuit 10 further includes a bandgap output buffer 105 (BG Buffer). One end of the bandgap output buffer 105 is connected to the bias circuit 104 , and the other end is connected to the first input end of the error amplifier 101 . The bandgap output buffer 105 is also connected between the first input terminal of the error amplifier 101 and the reference voltage converting circuit 20 .

The BG buffer is used to drive the input voltage to the input terminal of the error amplifier 101 and provide current. The compensation network 103 adopts a zero point compensation technique to compensate the phase margin of the LDO loop by introducing a zero point. The bias circuit 104 provides a stable bias voltage for the LDO.

Please refer to FIG. 4 . FIG. 4 is a schematic diagram of a simulation result of a low-dropout linear regulator that dynamically adjusts an output provided by an embodiment of the present application. Wherein, D is a voltage output demand command (adjustable gear input signal D[j:0]), VDDIN represents the first driving power supply, Vref is a reference voltage, and Vout is an output voltage. Based on the same 1.05v VDDIN, when the voltage adjustment gear is 3-bit D[2:0], it can generate 8 gears of different Vref and Vout, the output voltage range is 0.9V ~ 0.83V, and the step voltage interval is 10mV.

The solution of the present application also provides a system on chip, including: the above-mentioned low-dropout linear voltage regulator.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, there may be various modifications and changes in the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included within the protection scope of this application.

It will be apparent to those skilled in the art that the present application is not limited to the details of the exemplary embodiments described above, but that the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be regarded as exemplary and not restrictive in all points of view, and the scope of the application is defined by the appended claims rather than the foregoing description, and it is intended that the scope of the present application be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in this application. Any reference sign in a claim should not be construed as limiting the claim concerned.

Claims (6)

1. A low-dropout linear voltage regulator for dynamically adjusting output, characterized in that, the low-dropout linear voltage regulator includes a main circuit and a reference voltage conversion circuit, and the main circuit includes an error amplifier and an output voltage adjustment unit; The first input end of the error amplifier is connected to the output end of the reference voltage conversion circuit, the output of the error amplifier is single-connected to the first end of the output voltage adjustment unit, and the second input end of the error amplifier connected to the second end of the output voltage adjustment unit, the second end of the output voltage adjustment unit is also used to connect to the subsequent load circuit, and the third end of the output voltage adjustment unit is connected to the first driving power supply; The reference voltage conversion circuit is used to output a corresponding reference voltage based on a voltage output demand command; The error amplifier is configured to output a first control signal based on a comparison result between the output voltage of the output voltage adjustment unit and the reference voltage when an enable signal is received; The output voltage adjustment unit is configured to adjust the output voltage based on the first control signal; The reference voltage conversion circuit includes a management unit and a voltage division unit, the management unit is connected to the control terminal of the voltage division unit, the first terminal of the voltage division unit is connected to the second driving power supply, and the voltage division unit The second terminal of the voltage dividing unit is connected to the first input terminal of the error amplifier as the output terminal of the reference voltage conversion circuit; The management unit is configured to send a second control signal to the voltage dividing unit according to the voltage output demand command; The voltage dividing unit is configured to output a corresponding reference voltage after receiving the second control signal; The voltage dividing unit includes n voltage dividing resistors and n-1 switching tubes, where n is greater than or equal to 3; The n voltage dividing resistors are connected in series in sequence, and n-1 connecting terminals are drawn between adjacent resistors; Each connection terminal is respectively connected to the first pole of the corresponding switch tube, the second poles of the n-1 switch tubes are the control terminals of the voltage dividing unit, and are connected to the management unit, and the n- The third pole of one switch tube is connected to the output terminal of the voltage dividing unit; The second control signal includes a sub-control signal corresponding to each switch tube, the management unit is a decoder, the input terminal of the decoder is used to receive the voltage output demand instruction, and n-1 of the decoder The output terminals are connected to the second poles of the n-1 switch tubes in one-to-one correspondence; The decoder is used to generate n-1 sub-control signals according to the voltage output demand command, and send the n-1 sub-control signals to the second poles of the corresponding switching tubes respectively, so as to adjust the on-off of the corresponding switching tubes. off state. 2. The low dropout linear voltage regulator with dynamically regulated output as claimed in claim 1, characterized in that, at the same time, at most one switch tube is allowed to be in the conduction state. 3. The low-dropout linear voltage regulator with dynamically regulated output as claimed in claim 1, wherein the switch tube is a PMOS tube, and the source of the PMOS tube is used as the first pole of the switch tube, so The gate of the PMOS transistor is used as the second pole of the switch transistor, and the drain of the PMOS transistor is used as the third pole of the switch transistor. 4. The low-dropout linear voltage regulator for dynamically adjusting output as claimed in claim 1, wherein the output voltage adjusting unit comprises a PMOS transistor or a plurality of parallel-connected PMOS transistors; Alternatively, the output voltage adjustment unit includes one NMOS transistor or multiple NMOS transistors connected in parallel. 5. the low-dropout linear voltage regulator of dynamic adjustment output as claimed in claim 1, is characterized in that, the inverting input end of described error amplifier is connected to the output end of described reference voltage conversion circuit as its first input end , the non-inverting input terminal of the error amplifier is connected to the second terminal of the output voltage adjustment unit as its second input terminal. 6. A system on chip, characterized by comprising: the low dropout linear voltage regulator according to any one of claims 1-5.