Linear voltage regulator and electronic device

Abstract

The application provides a linear voltage stabilizer and electronic equipment, and relates to the technical field of electronic circuits.The linear voltage stabilizer comprises a starting circuit, a transient enhancement circuit and an output circuit connected in sequence.The starting circuit is used for providing a starting voltage.The transient enhancement circuit is used for transmitting the starting voltage so as to output an output voltage corresponding to the starting voltage through the output circuit.The transient enhancement circuit is further used for performing fast output control on the output voltage when the output voltage fluctuates, so as to stabilize the output of the output voltage.The linear voltage stabilizer and the electronic equipment provided by the application can complete starting before a reference level is established, so as to ensure normal working of the linear voltage stabilizer.The introduced transient enhancement circuit can greatly improve the load response speed of the linear voltage stabilizer, so that the linear voltage stabilizer of the application can be applied to various application scenarios and has high efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic circuits, and in particular to a linear voltage regulator and an electronic device. BACKGROUND

[0002] The power supply scheme is the primary problem faced by electronic devices. The 220V alternating current for civilian use or the 380V alternating current for industrial use generally needs to be stepped down and AC-DC converted before being safely supplied to the internal power supply of the electronic device. For the chips inside the electronic device, generally, direct current power supply can be low-voltage power supply such as 5V or higher-voltage power supply such as 24V, 36V, etc. If it is high-voltage power supply, the chip needs to integrate a linear voltage regulator to obtain a relatively stable output voltage for internal use.

[0003] The linear voltage regulator is generally composed of a feedback circuit, an error amplifier, a power tube and a compensation circuit. According to the actual application requirements, the performance of the linear voltage regulator will have different emphases, such as high precision, low noise, high power supply rejection ratio, fast response speed, etc. However, the commonly used linear voltage regulator generally needs a reference level to be normally used, and in some projects, there may be no reference level or inaccurate reference level, and when there is a large change in the power supply or the load, it will also cause the change of the output voltage of the linear voltage regulator, which is difficult to stabilize the output. SUMMARY

[0004] Therefore, the purpose of the present application is to provide a linear voltage regulator and an electronic device to alleviate the above technical problems.

[0005] In a first aspect, an embodiment of the present application provides a linear voltage regulator, comprising: a start-up circuit, a transient enhancement circuit and an output circuit connected in sequence; wherein the start-up circuit is configured to provide a start-up voltage, the transient enhancement circuit is configured to transmit the start-up voltage to output an output voltage corresponding to the start-up voltage through the output circuit; and the transient enhancement circuit is configured to output adjust the output voltage when the fluctuation of the output voltage exceeds a preset threshold, so as to stabilize the output of the output voltage.

[0006] With reference to the first aspect, in a first possible implementation manner of the first aspect, the starting circuit comprises a voltage generating circuit and a starting power tube; an input end of the voltage generating circuit is configured to be connected with an external power supply, and is configured to provide the starting voltage; an output end of the voltage generating circuit is connected with a gate of the starting power tube; a drain of the starting power tube is connected with the output circuit; and a source of the starting power tube is connected with the transient enhancement circuit; the voltage generating circuit is configured to generate a voltage signal, the starting voltage is generated by the voltage signal through the starting power tube, and the starting voltage is transmitted to the output circuit through the transient enhancement circuit for output.

[0007] With reference to the first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, the voltage generating circuit comprises a current source and a regulating resistor connected in series with the current source; and an output end of the voltage generating circuit is arranged at a connection point of the current source and the regulating resistor.

[0008] With reference to the first possible implementation manner of the first aspect, in a third possible implementation manner of the first aspect, the output circuit comprises an adjusting power tube, a pull-down circuit and an output interface; a gate of the adjusting power tube is connected with a drain of the starting power tube; a source of the adjusting power tube is connected with the external power supply; a drain of the adjusting power tube is connected to the output interface; and one end of the pull-down circuit is connected with the drain of the adjusting power tube, and the other end of the pull-down circuit is grounded.

[0009] With reference to the third possible implementation manner of the first aspect, in a fourth possible implementation manner of the first aspect, the transient enhancement circuit comprises a first current mirror and a second current mirror; the first current mirror comprises a plurality of first power tubes; gates of the plurality of first power tubes are connected with a gate of the starting power tube; drains of the plurality of first power tubes are connected with the second current mirror; sources of the plurality of first power tubes are connected with the output interface; the second current mirror comprises a plurality of second power tubes; gates of the plurality of second power tubes are connected with a preset current source, and the preset current source is connected with the external power supply; drains of the plurality of second power tubes are connected with the first current mirror; and sources of the plurality of second power tubes are grounded.

[0010] With reference to the fourth possible implementation manner of the first aspect, in a fifth possible implementation manner of the first aspect, the output circuit further comprises a clamping power tube; a drain of the clamping power tube is connected with a source of the starting power tube, and the drain of the clamping power tube and the source of the starting power tube are further connected to two of the second power tubes in the second current mirror through an off power tube.

[0011] With reference to the fourth possible implementation manner of the first aspect, the embodiments of the present application provide a sixth possible implementation manner of the first aspect, wherein one power tube of the first current mirror and one power tube of the second current mirror constitute a first current comparator; the first current comparator is provided with a first output point, which is connected to the gate of the turn-off power tube.

[0012] With reference to the fourth possible implementation manner of the first aspect, the embodiments of the present application provide a seventh possible implementation manner of the first aspect, wherein one power tube of the first current mirror and one power tube of the second current mirror constitute a second current comparator; the power tubes constituting the second current comparator are different from the power tubes constituting the first current comparator; the second current comparator is further provided with a second output point, which is connected to the gate of a second turn-off power tube; the drain of the second turn-off power tube is connected to the external power supply, for charging the gate of the adjusting power tube; the source of the second turn-off power tube is connected to the ground.

[0013] With reference to the third possible implementation manner of the first aspect, the embodiments of the present application provide an eighth possible implementation manner of the first aspect, wherein the linear voltage regulator further comprises an operational amplifier feedback regulation loop; the operational amplifier feedback regulation loop is provided with an operational amplifier chip, one input end of the operational amplifier chip is connected to the output interface, to obtain a feedback voltage corresponding to the output voltage; the other input end of the operational amplifier chip is used to obtain a preset reference voltage; the output end of the operational amplifier chip is connected to the starting circuit, to regulate the output voltage of the starting circuit.

[0014] In the second aspect, the embodiments of the present application further provide an electronic device, which is configured with the linear voltage regulator of the first aspect.

[0015] The embodiments of the present application have the following beneficial effects:

[0016] The linear voltage regulator and the electronic device provided by the embodiments of the present application can provide a starting voltage through the starting circuit, and transmit the starting voltage through the transient enhancement circuit, to output an output voltage corresponding to the starting voltage through the output circuit; and the transient enhancement circuit can further output regulate the output voltage when the fluctuation of the output voltage exceeds a preset threshold, to stabilize the output of the output voltage; the starting circuit can complete starting before the reference level is established, to ensure the normal work of the linear voltage regulator; the introduced transient enhancement circuit can greatly improve the load response speed of the linear voltage regulator, not only making the linear voltage regulator applicable to various application scenarios, but also improving the use efficiency of the linear voltage regulator.

[0017] Other features and advantages of the present application will be set forth in the descriptions that follow, and in part will be apparent from the description, or can be learned by practice of the application. The purposes and other advantages of the application will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

[0018] In order to make the above objectives, features and advantages of the present application more apparent, the following will describe a preferred embodiment in detail, and the accompanying drawings will be described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0020] Figure 1 A structural block diagram of a linear voltage regulator provided by the embodiment of the present application is provided.

[0021] Figure 2 A circuit schematic diagram of a linear voltage regulator provided by the embodiment of the present application is provided.

[0022] Figure 3 Another circuit schematic diagram of a linear voltage regulator provided by the embodiment of the present application is provided. DETAILED DESCRIPTION

[0023] In order to make the objectives, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the present application will be described clearly and completely in the following with reference to the drawings. Obviously, the described embodiments are some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0024] At present, in chip design, the power supply voltage range is relatively wide, which cannot be directly used for power supply of internal devices of the chip, so a circuit module is needed to convert the voltage varying in a wide range from outside to a relatively stable low voltage power supply voltage inside, and the linear voltage regulator is a module to realize this function.

[0025] Generally, the linear voltage regulator needs a reference level to work normally, but in actual projects, there may be no reference level provided or the reference level may be inaccurate, so a linear voltage regulator that can be started independently and work normally is needed.

[0026] Further, the transient response characteristic is an important index of the linear regulator. In a large-current linear regulator with a P-type power tube as an output, if a main pole is at a gate GATE end of the power tube, then a bandwidth of a loop is necessarily small, and a loop response speed is very slow. In this case, if a power supply or a load has a large change instantaneously, then a change of an output voltage of the linear regulator is caused. When the output voltage is not recovered to a normal working voltage for a long time, then internal other circuits can be caused to be in error, and a serious problem can cause a chip to be burned. Therefore, a transient response enhancement circuit needs to be added in the linear regulator. The transient response enhancement circuit enhances a transient characteristic of the loop when an error amplifier loop has not responded yet, and helps the output voltage of the linear regulator to be quickly recovered to the normal output voltage.

[0027] Based on this, the linear regulator and the electronic device provided by the embodiment of the present application can realize starting without a reference voltage, and can also quickly respond to a change of an output voltage of the linear regulator, so as to improve overall stability.

[0028] In order to facilitate understanding of the embodiment, first, a linear regulator disclosed by the embodiment of the present application is introduced in detail.

[0029] In a possible implementation manner, the embodiment of the present application provides a linear regulator, as shown in a structure block diagram of a linear regulator. Figure 1 The linear regulator in the embodiment of the present application includes: a starting circuit 10, a transient enhancement circuit 20 and an output circuit 30 connected in sequence.

[0030] The starting circuit 10 is used for providing a starting voltage, and the transient enhancement circuit 20 is used for transmitting the starting voltage, so as to output an output voltage corresponding to the starting voltage through the output circuit 30.

[0031] Further, the transient enhancement circuit 20 is also used for performing output control on the output voltage when a fluctuation of the output voltage exceeds a preset threshold, so as to make the output voltage to be stably output.

[0032] The linear regulator provided by the embodiment of the present application can provide the starting voltage through the starting circuit, and transmit the starting voltage through the transient enhancement circuit, so as to output the output voltage corresponding to the starting voltage through the output circuit. Further, the transient enhancement circuit can perform output adjustment on the output voltage when the fluctuation of the output voltage exceeds the preset threshold, so as to make the output voltage to be stably output. The starting circuit can be completed before the reference level is established, so as to ensure normal working of the linear regulator. The introduced transient enhancement circuit can greatly improve a load response speed of the linear regulator, not only makes the linear regulator to be applicable to various application scenarios, but also improves use efficiency of the linear regulator.

[0033] In actual use, the starting circuit 10 comprises a voltage generating circuit and a starting power tube; an input end of the voltage generating circuit is connected with an external power supply for providing a starting voltage; an output end of the voltage generating circuit is connected with a gate of the starting power tube; a drain of the starting power tube is connected with the output circuit 30; and a source of the starting power tube is connected with the transient enhancement circuit.

[0034] The voltage generating circuit is configured to generate a voltage signal, the starting power tube is configured to generate a starting voltage based on the voltage signal, and the transient enhancement circuit is configured to transmit the starting voltage to the output circuit for output.

[0035] For the convenience of understanding, in the following, Figure 1 , Figure 2 a circuit schematic diagram of a linear voltage stabilizer is further shown, as shown in Figure 2 , a starting circuit, a transient enhancement circuit and an output circuit are shown, and the starting circuit comprises a voltage generating circuit and a starting power tube, wherein, Figure 2 the power tube M7 is the starting power tube, and further, Figure 2 the voltage generating circuit comprises a current source I1 and a regulating resistor connected in series with the current source I1, wherein, in the embodiment of the present application, the regulating resistor is composed of two series-connected resistors, i.e., Figure 2 the resistors R3 and R4 in the above, and the output end of the voltage generating circuit is arranged at the connection point of the current source and the regulating resistor.

[0036] Further, as shown in Figure 2 , the output circuit comprises an adjusting power tube, a pull-down circuit and an output interface; wherein, Figure 2 the power tube M24 in the above is the adjusting power tube, the pull-down circuit comprises series-connected resistors R5 and R6, and the drain of the adjusting power tube M24 is connected with the connection point of the pull-down circuit, which is the output interface VOUT.

[0037] Specifically, the gate of the adjusting power tube M24 is connected with the drain of the starting power tube M7, the source of the adjusting power tube M24 is connected with an external power supply VCC, and the drain of the adjusting power tube M24 is connected with the output interface; one end of the pull-down circuit is connected with the drain of the adjusting power tube M24, and the other end is grounded.

[0038] Further, Figure 2 the transient enhancement circuit comprises a first current mirror and a second current mirror; the first current mirror comprises a plurality of first power tubes, i.e., power tubes M8, M19, M20 and M21, the gates of the plurality of first power tubes are all connected with the gate of the starting power tube M7; the drains of the plurality of first power tubes are all connected with the second current mirror; and the sources of the plurality of first power tubes are all connected with the output interface.

[0039] Further, the second current mirror comprises a plurality of second power tubes, i.e. power tubes M9, M10, M11, M12, M13; a preset current source is connected to the gates of the plurality of second power tubes, and the preset current source is connected to an external power source; the drains of the plurality of second power tubes are all connected to the first current mirror; and the sources of the plurality of second power tubes are all grounded.

[0040] Further, the output circuit further comprises a clamping power tube, i.e. a clamping power tube M8 in Figure 2 The drain of the clamping power tube is connected to the source of the start-up power tube M7, and the drain of the clamping power tube M8 and the source of the start-up power tube M7 are further connected to two second power tubes in the second current mirror, i.e. M10 and M11 in Figure 2

[0041] Based on the circuit schematic diagram of the linear voltage regulator shown in Figure 2 As long as an initial bias current I1 flows through resistors R3 and R4 when a reference voltage-free start-up is performed, a fixed voltage V_GATE, i.e. the start-up voltage of the embodiment of the present application, can be obtained, and current sources I2 and I3 can be obtained through the mirrored current I1. When the start-up power tube M7 is not turned on, the source of the start-up power tube M7 is pulled down to GND, and at this time, if the V_GATE exceeds the threshold voltage of the start-up power tube M7, the GATE of the adjustment power tube M24 is pulled down, and finally, the output voltage VOUT of the output interface is clamped by the clamping power tube M8 at V_GATE+VGS(M8), i.e. the output voltage VOUT can be stably output even without a reference voltage.

[0042] Further, one power tube of the first current mirror and one power tube of the second current mirror constitute a first current comparator; the first current comparator is provided with a first output point, and the first output point is connected to the gate of the turn-off power tube M18.

[0043] Specifically, Figure 2 The power tube M19 of the first current mirror and the power tube M12 of the second current mirror constitute the first current comparator, and when the current of the power tube M19 is stronger than that of the power tube M12, the output level of the first output point A is high, and vice versa.

[0044] Further, one power tube of the first current mirror and one power tube of the second current mirror constitute a second current comparator; the power tubes constituting the second current comparator are different from the power tubes constituting the first current comparator; specifically, the power tube M21 of the first current mirror and the power tube M13 of the second current mirror constitute the second current comparator, and the second current comparator is further provided with a second output point, i.e. Figure 2 ​The second output point B is connected with the gate of the second off power tube M17; the drain of the second off power tube M17 is connected with an external power source for charging the gate of the adjusting power tube M24; the source of the second off power tube M17 is connected with the ground; the drain of the second off power tube M17 is further provided with the power tube group M22 and M23, which are connected with the external power source; the source of the second off power tube M17 is further provided with the power tube group M14 and M15, which are grounded; and the second output point B is further connected with a power tube M16, the gate of which is connected with the second output point B, the source of which is grounded, and the drain of which is connected with an output interface VOUT.

[0045] Further, based on the circuit schematic diagram of the linear voltage regulator shown in Figure 2 When the initial bias current I1 has an initial current flowing through the resistors R3 and R4, a fixed voltage V_GATE is generated; in normal operation, the output voltage VOUT is clamped at a fixed value (VOUT=V_GATE+VGS_M8) by the VGS of the clamping power tube M8 and the V_GATE voltage, which is the designed output voltage value of the linear voltage regulator, i.e., the set value, which can be adjusted by adjusting the initial current I1 or the resistance value of the resistors R3 and R4 to adjust the set value of the output voltage.

[0046] When the power supply voltage (external power source) VCC is higher than the set value, the output voltage of the linear voltage regulator is the set value; when the power supply voltage is lower than the set value, the current of the clamping power tube M8 disappears, the current of the starting power tube M7 increases, and then the starting power tube M7 pulls down the GATE of the adjusting power tube M24, and the adjusting power tube M24 works in the linear region, at this time, the output voltage VOUT≈VCC.

[0047] And in actual use, Figure 2 The starting power tube M7, the second off power tube M17 and the adjusting power tube M24 in the linear voltage regulator are high-voltage tubes, so the input voltage range of the linear voltage regulator in the embodiment of the present application can be from 2.5V to the maximum withstand voltage of the high-voltage tube.

[0048] Further, based on the circuit schematic diagram of the linear voltage regulator shown in Figure 2 When the initial bias current I1 has an initial current flowing through the resistors R3 and R4, a fixed voltage V_GATE is generated; in normal operation, the output voltage VOUT is clamped at a fixed value (VOUT=V_GATE+VGS_M8) by the VGS of the clamping power tube M8 and the V_GATE voltage, which is the designed output voltage value of the linear voltage regulator, i.e., the set value, which can be adjusted by adjusting the initial current I1 or the resistance value of the resistors R3 and R4 to adjust the set value of the output voltage.

[0049] Figure 3In the middle, the power tube M8, M19, M20, M21 constitutes the first current mirror, wherein the current I_M8 of M8 = I_M10 + I_M18 - I_M7, wherein I_M10, I_M18, I_M7 represent the current of M10, M18 and M7 respectively, the power tube M9, M10, M11, M12, M13 constitutes the second current mirror, for providing bias. The power tube M12 and the power tube M19 constitute the first current comparator, when the current of the power tube M19 is higher than that of the power tube M12, the output level of the first output point A point is high, and vice versa. The power tube M21 and the power tube M13 constitute the second current comparator. In the steady state, the pull-down current of the power tube M12 is weaker than that of the power tube M19, the first output point A point is high, at this time the power tube M18 is in the off state, the pull-down current of the power tube M13 is higher than that of the power tube M21, the second output point B point is low, and the second off power tube M17 is in the off state. If the output voltage VOUT voltage suddenly rises, because V_GATE is relatively stable, the VGS of the first power tube in the first current mirror of the clamping power tube M8 will increase instantaneously, at this time there are three loops to adjust the voltage of VOUT:

[0050] The first loop includes the clamping power tube M8, the starting power tube M7 and the adjusting power tube M24, wherein the current of the clamping power tube M8 increases, the current of the starting power tube M7 decreases, I3 pulls up the GATE of the adjusting power tube M24, thereby reducing the current flowing through the adjusting power tube M24, and finally the output voltage VOUT gradually falls to the set value (VOUT = V_GATE + VGS_M8);

[0051] The second loop includes the power tube M21, the second off power tube M17, the power tube M22, M23 and the adjusting power tube M24, wherein the current of the power tube M21 increases, the B point becomes high, the second off power tube M17 opens, and then charges the GATE of the adjusting power tube M24 through M22, M23 to make it increase rapidly;

[0052] The third loop includes the power tube M21 and the power tube M16, wherein the power tube M16 in the pull-down circuit directly pulls down and bleeds the output voltage VOUT.

[0053] The adjusting speed of the first loop is directly related to the current size of I3. Generally, I3 will not be too large, because too large will affect the recovery speed of the output voltage VOUT after undershoot, therefore, the current path controlled by the second off power tube M17 can speed up the recovery speed of the output voltage VOUT overshoot.

[0054] Similarly, if the output voltage VOUT suddenly decreases, the current of the clamping power tube M8 and the power tube M19 decreases, the voltage of point A decreases to turn off the power tube M18, the current of the power tube M7 increases several times, and then the GATE of the regulating power tube M24 is quickly pulled down to increase the current of the regulating power tube M24, thereby restoring the output voltage VOUT, so that the turn-off power tube M18 control loop can effectively speed up the recovery speed of the VOUT undershoot, thereby realizing the function of transient enhancement of the circuit, and therefore, the transient enhancement circuit in the embodiment of the present application actually stabilizes the output voltage VOUT at a certain preset voltage, and the value of the preset voltage is related to the reference voltage.

[0055] In actual use, the current of the loop in which the turn-off power tube M18 and the second turn-off power tube M17 are located is controlled by the second current mirror during the transient enhancement process, and in actual use, the second current mirror can also be removed, that is, the source of the turn-off power tube M18 and the second turn-off power tube M17 can be directly grounded or grounded through a current-limiting resistor, and the specific setting is made according to the actual use, and the embodiment of the present application does not limit this.

[0056] Further, the regulating resistor of the voltage generating circuit is composed of two series-connected resistors R3 and R4, which can provide a voltage signal, and in actual use, the resistors R3 and R4 in the regulating resistor can also be replaced by other devices with clamping function, and the specific setting can be made according to the actual use, and the embodiment of the present application also does not limit this.

[0057] Further, the linear voltage stabilizer provided by the embodiment of the present application can also be provided with an operational amplifier feedback regulation loop.

[0058] Specifically, the operational amplifier feedback regulation loop is provided with an operational amplifier chip, one input end of the operational amplifier chip is connected to an output interface of the output circuit 30 to obtain a feedback voltage corresponding to the output voltage, the other input end of the operational amplifier chip is used to obtain a preset reference voltage, and the output end of the operational amplifier chip is connected to the start-up circuit to regulate the output voltage of the start-up circuit.

[0059] Since the operational amplifier feedback regulation loop only makes the variation range of the output voltage smaller, in actual use, the operational amplifier feedback regulation loop in the linear voltage stabilizer can be omitted, and of course, in other embodiments, the operational amplifier feedback regulation loop can be retained, that is, the voltage generating circuit and the operational amplifier feedback regulation loop are retained in the linear voltage stabilizer at the same time to ensure the normal start of the linear voltage stabilizer and make the output more accurate.

[0060] In order to facilitate understanding, Figure 3 a circuit schematic diagram of another linear voltage stabilizer is shown, wherein, Figure 2 a schematic diagram of the operational amplifier feedback regulation loop is shown. Compared with the circuit schematic diagram of the linear voltage stabilizer shown in Fig.Figure 3 , Figure 3 The specific circuit structure of the current source I1-3 is shown in the embodiment, and the power tubes M1-M3 and the resistors R1 and R2 constitute a current generating circuit. The power tubes M4-M6 mirror the current of the power tube M3 respectively, and supply the obtained current to the circuit components connected thereto. Specifically, in the current generating circuit, one end of the resistor R2 is connected to VCC, the other end is connected to the drain of the power tube M1, the source of the power tube M1 is grounded, the drain is connected to one end of the resistor R1, the other end of the resistor R1 is grounded, and the gate of the power tube M2 is connected to the drain of the power tube M1, the source of the power tube M2 is connected to one end of the resistor R1, and the drain of the power tube M2 is connected to the drain of the power tube M3, the source of the power tube M3 is connected to VCC, and the gate of the power tube M3 is connected to the current mirror composed of the power tubes M4-M6.

[0061] The specific model and connection mode of the power tube can refer to the circuit diagram shown in Figure 3 It should be understood that, Figure 3 The current generating circuit shown is only one possible implementation in the embodiment of the application, and in other embodiments, the specific form of the current generating circuit, and the model and parameters of the various power tubes and the like can be set according to actual use, and the embodiment of the application does not limit this.

[0062] Specifically, Figure 3 In the embodiment, the operational amplifier chip is denoted as OTA, the positive input end is used to obtain a preset reference voltage, and the negative input end is connected to an output interface. Specifically, Figure 3 In the embodiment, the negative input end is directly connected to a pull-down circuit, and the output voltage is divided by the resistors R5 and R6 to obtain the voltage value after the output voltage is divided as a corresponding feedback voltage.

[0063] At this time, the operational amplifier chip OTA can clamp VOUT at a fixed value according to the reference voltage and the feedback voltage.

[0064] And if there is no other power supply in the circuit, the power supply of the operational amplifier chip OTA and the reference voltage is also VOUT, so at the time of starting, they have not yet worked normally. If the output end of the operational amplifier chip OTA is directly connected to V_GATE, i.e., the gate of the starting power tube, the entire linear voltage regulator may fail to start due to the leakage of the output end of the operational amplifier chip OTA at the time of small current starting.

[0065] And ​The circuit schematic diagram of the shown operational amplifier feedback regulation loop can ensure normal starting of the voltage stabilizer, even if the operational amplifier chip OTA has not worked normally, that is, the output of the operational amplifier chip OTA is minimum 0, as long as it is ensured that V_GATE generated by the initial current flowing through the resistor R3 can open the starting power tube M7.

[0066] In conclusion, the linear voltage stabilizer provided by the embodiment of the present application can greatly improve the load response speed of the linear voltage stabilizer by introducing the transient enhancement circuit. Moreover, the linear voltage stabilizer provided by the embodiment of the present application can adapt to a wider input voltage range, when the input voltage is less than or equal to the set output voltage, the actual output voltage of the linear voltage stabilizer is approximately equal to the input voltage, when the input voltage is greater than the set output voltage, the output of the linear voltage stabilizer is equal to the set voltage, and the linear voltage stabilizer in the embodiment of the present application can complete starting and normal work before the reference level is established, which not only enables the linear voltage stabilizer to be applicable to various application scenarios, but also improves the use efficiency of the linear voltage stabilizer.

[0067] Further, the embodiment of the present application further provides an electronic device, which is configured with the linear voltage stabilizer provided by the above-mentioned embodiment.

[0068] The electronic device provided by the embodiment of the present application has the same technical features as the linear voltage stabilizer provided by the above-mentioned embodiment, so it can also solve the same technical problems and achieve the same technical effects.

[0069] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the electronic device described above can refer to the corresponding process in the foregoing method embodiment, which will not be described here.

[0070] In addition, in the description of the embodiment of the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection" and "connection" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected, it can be mechanical connection, or electrical connection, it can be directly connected, or indirectly connected through an intermediate medium, it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0071] If the functions are realized in the form of software function units and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application or the parts of the present application that essentially contribute to the prior art or the parts of the technical solutions can be embodied in the form of software products. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the various embodiments of the present application. The aforementioned storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0072] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0073] Finally, it should be noted that: the above embodiments are only specific embodiments of the present application, which are used to illustrate the technical solutions of the present application, and are not limited thereto, the protection scope of the present application is not limited thereto, although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art within the technical range disclosed by the present application can modify or easily think of changes to the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part of the technical features; and these modifications, changes or replacements do not make the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A linear voltage regulator, characterized by, The application relates to a starting circuit, a transient enhancement circuit and an output circuit connected in sequence. The starting circuit is used for providing a starting voltage, and the transient enhancement circuit is used for transmitting the starting voltage to output an output voltage corresponding to the starting voltage through the output circuit. The transient enhancement circuit is used for output adjusting the output voltage when the fluctuation of the output voltage exceeds a preset threshold, so that the output voltage is stably output. The starting circuit comprises a voltage generating circuit and a starting power tube; the output end of the voltage generating circuit is connected with the gate of the starting power tube; the drain of the starting power tube is connected with the output circuit; and the source of the starting power tube is connected with the transient enhancement circuit. The output circuit comprises an adjusting power tube and an output interface. The gate of the adjusting power tube is connected with the drain of the starting power tube; the source of the adjusting power tube is connected with an external power supply; and the drain of the adjusting power tube is connected with the output interface. The transient enhancement circuit comprises a first current mirror and a second current mirror. The first current mirror comprises a plurality of first power tubes. The gates of the plurality of first power tubes are connected with the gate of the starting power tube; the drains of the plurality of first power tubes are connected with the second current mirror; and the sources of the plurality of first power tubes are connected with the output interface. The second current mirror comprises a plurality of second power tubes. The gates of the plurality of second power tubes are connected with a preset current source, and the preset current source is connected with an external power supply. The drains of the plurality of second power tubes are connected with the first current mirror; and the sources of the plurality of second power tubes are grounded. The input end of the voltage generating circuit is connected with an external power supply, and is used for providing the starting voltage.

2. The linear voltage regulator of claim 1, wherein, The voltage generating circuit is used for generating a voltage signal, the voltage signal generates the starting voltage through the starting power tube, and is transmitted to the output circuit through the transient enhancement circuit to be output. The voltage generating circuit comprises a current source and an adjusting resistor connected in series with the current source.

3. The linear voltage regulator of claim 2, wherein, The output end of the voltage generating circuit is arranged at the connection point of the current source and the adjusting resistor. The output circuit further comprises a pull-down circuit.

4. The linear voltage regulator of claim 2, wherein, One end of the pull-down circuit is connected with the drain of the adjusting power tube, and the other end is grounded. The output circuit further comprises a clamping power tube.

5. The linear voltage regulator of claim 1, wherein, The drain of the clamping power tube is connected with the source of the starting power tube, and the drain of the clamping power tube and the source of the starting power tube are further connected with two second power tubes in the second current mirror through an off power tube. One power tube of the first current mirror and one power tube of the second current mirror constitute a first current comparator.

6. The linear voltage regulator of claim 5, wherein, The first current comparator is provided with a first output point, and the first output point is connected with the gate of the off power tube. One power tube of the first current mirror and one power tube of the second current mirror constitute a second current comparator, and the power tubes constituting the second current comparator are different from the power tubes constituting the first current comparator.

7. The linear voltage regulator of claim 6, wherein, ​ The second current comparator is also provided with a second output point connected with the gate of the second off power tube; The drain of the second off power tube is connected with the external power supply, for charging the gate of the adjusting power tube; The source of the second off power tube is connected with the ground.

8. The linear voltage regulator of claim 4, wherein, The linear voltage stabilizer further comprises an operational amplifier feedback adjusting loop; The operational amplifier feedback adjusting loop is provided with an operational amplifier chip, one input end of the operational amplifier chip is connected with the output interface to obtain the feedback voltage corresponding to the output voltage; The other input end of the operational amplifier chip is used for obtaining the preset reference voltage; The output end of the operational amplifier chip is connected with the starting circuit to adjust the output voltage of the starting circuit.

9. An electronic device, comprising: The electronic equipment is configured with the linear voltage stabilizer of any one of claims 1-8.

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