Operational amplifier module, linear voltage regulator circuit and chip

Abstract

The present application relates to an operational amplifier module, a linear voltage regulator circuit and a chip. The module includes: an input stage unit, which is used to obtain the difference information between the input reference voltage and the feedback voltage according to the input reference voltage and the feedback voltage; a load unit, which is used to generate a first voltage based on the difference information; wherein the first voltage represents the output voltage of the operational amplifier module; a line loss compensation unit, which is used to detect the change of the load current of the linear regulator according to the first voltage, and provide a compensation current to the load unit according to the change, so as to increase the output voltage of the linear regulator, so that the voltage of the external load end connected to the linear regulator maintains the target voltage. This method can detect the change of the load current of the linear regulator, and provide a compensation current according to the change to increase the output voltage of the linear regulator, so as to reduce the voltage drop effect formed by the transmission path and improve the accuracy of the output voltage.

Description

Technical Field

[0001] The present application relates to the technical field of integrated circuits, and in particular to an operational amplifier module, a linear voltage regulator circuit and a chip. Background Art

[0002] As portable electronic products are widely used in all aspects of work and life, higher requirements are placed on the performance of power supplies. As an important input voltage management module, linear regulators (LDOs) are widely used in chip design due to their low noise, low cost, and fast transient characteristics.

[0003] See also Figure 1 , the LDO circuit in traditional technology is as follows Figure 1 As shown, VIN is the power supply voltage, VREF is the reference voltage, VFB is the feedback voltage, OP is the operational amplifier, P0 is the P-type power tube, resistors R1 and R2 are the feedback resistors of the LDO circuit, VOUTpad is the circuit output voltage point inside the chip, which is connected to the corresponding package pin through the bonding wire and then connected to the external load, VOUT is the power supply voltage VOUT received by the power supply end of the external load, and Rw is the impedance corresponding to the bonding wire.

[0004] Since the resistance of Rw is small, generally in the ohm level; and the resistance of resistors R1 and R2 is large, generally in the 100kΩ~MΩ level, when the load current Iout is small, Rw can be ignored when calculating the VOUT value. At this time, the expression of the VOUT voltage value is:

[0005] VOUT = VOUTpad = VREF × (1 + (R1 / R2)

[0006] When there is a large load current Iout, the voltage drop on Rw will increase with the increase of Iout. At this time, the expression of VOUT voltage value is:

[0007] VOUT=VOUTpad-Iout×Rw= VREF×(1+(R1 / R2)-Iout×Rw

[0008] Assuming Rw is 5 ohms and Iout is 20mA, VOUT is 100mV lower than the no-load voltage. If the LDO output voltage is 3V at this time, VOUT will drop to 2.9V, which exceeds the 1% accuracy.

[0009] Therefore, how to reduce the voltage drop effect formed on the transmission path when the load current is large and ensure the accuracy of the output voltage has become an urgent problem to be solved. Summary of the invention

[0010] Based on this, it is necessary to provide an operational amplifier module, a linear voltage regulator circuit and a chip to address the above technical problems, so as to solve the problem that when the load current is large in traditional technology, the voltage drop caused by the transmission path on the output voltage affects the output voltage accuracy.

[0011] In a first aspect, the present application provides an operational amplifier module, which is applied to a linear regulator, and the module includes:

[0012] The input stage unit is used to obtain the difference information between the input reference voltage and the feedback voltage according to the input reference voltage and the feedback voltage;

[0013] A load unit, configured to generate a first voltage based on the difference information; wherein the first voltage represents an output voltage of the operational amplifier module;

[0014] The line loss compensation unit is used to detect the change of the load current of the linear regulator according to the first voltage, and provide a compensation current for the load unit according to the change to increase the output voltage of the linear regulator so that the voltage of the external load terminal connected to the linear regulator maintains the target voltage.

[0015] In one of the embodiments, the line loss compensation unit includes: a first transistor;

[0016] The control terminal of the first transistor is connected to the first voltage, the first terminal is connected to the power supply voltage, and the second terminal is connected to the load unit;

[0017] Wherein, the first transistor is a PMOS transistor.

[0018] In one of the embodiments, the line loss compensation unit includes: a first transistor, a second transistor and a third transistor;

[0019] The control end of the first transistor is connected to the first voltage, and the first end is connected to the power supply voltage; the second end of the second transistor, the control end of the second transistor and the control end of the third transistor are connected, and then connected to the second end of the first transistor;

[0020] The first end of the second transistor and the first end of the third transistor are connected to the ground line, and the second end of the third transistor is connected to the load unit;

[0021] The first transistor is a PMOS transistor, and the second transistor and the third transistor are NMOS transistors.

[0022] In one of the embodiments, the input stage unit includes: a fourth transistor and a fifth transistor;

[0023] The control terminal of the fourth transistor is used as the first input terminal of the input stage unit and is connected to the reference voltage;

[0024] The control terminal of the fifth transistor serves as the second input terminal of the input stage unit and is connected to the feedback voltage;

[0025] After the first end of the fourth transistor and the first end of the fifth transistor are connected, the third input end of the input stage unit is connected to the power supply voltage;

[0026] The second end of the fourth transistor serves as the first output end of the input stage unit and is connected to the first input end of the load unit;

[0027] The second end of the fifth transistor serves as the second output end of the input stage unit and is connected to the second input end of the load unit;

[0028] Wherein, the fourth transistor and the fifth transistor are PMOS transistors.

[0029] In one embodiment, the input stage unit further comprises:

[0030] The current source subunit is used to connect or disconnect the connection channel between the power supply voltage and the input stage unit according to the input bypass signal, so as to provide a current signal for the input stage unit.

[0031] In one of the embodiments, the current source subunit includes: a sixth transistor;

[0032] The control terminal of the sixth transistor is connected to the bypass signal, and the first terminal is connected to the power supply voltage;

[0033] The second end of the sixth transistor serves as the output end of the current source sub-unit and is connected to the third input end of the input stage unit.

[0034] In one embodiment, the load unit includes a first load subunit and a second load subunit; the first load subunit includes a seventh transistor and an eighth transistor, and the second load subunit includes a ninth transistor, a tenth transistor, an eleventh transistor, and a twelfth transistor;

[0035] The control end of the seventh transistor, the second end of the seventh transistor and the control end of the eighth transistor are connected, and then connected to the second end of the eleventh transistor;

[0036] The first end of the seventh transistor and the first end of the eighth transistor are connected to the power supply voltage;

[0037] After the second end of the eighth transistor is connected to the second end of the twelfth transistor, the second end serves as the output end of the load unit to output the first voltage;

[0038] After the control end of the ninth transistor, the second end of the ninth transistor and the control end of the eleventh transistor are connected, they serve as the first input end of the load unit and are connected to the first output end of the input stage unit;

[0039] After the control end of the tenth transistor, the second end of the tenth transistor and the control end of the twelfth transistor are connected, they serve as the second input end of the load unit and are connected to the second output end of the input stage unit;

[0040] First ends of the ninth transistor, the tenth transistor, the eleventh transistor and the twelfth transistor are respectively connected to ground lines.

[0041] In a second aspect, the present application further provides a linear voltage stabilization circuit, the circuit comprising:

[0042] The operational amplifier module described in any one of the first aspects above is used to output a first voltage according to an input reference voltage and a feedback voltage, and detect a change in a load current of an external load of the linear voltage regulator circuit, and provide a compensation current for a load unit of the operational amplifier module according to the change, so as to increase the output voltage of the linear voltage regulator circuit, so that the voltage of an external load terminal connected to the linear voltage regulator maintains a target voltage;

[0043] a power module, configured to adjust an output current of the linear voltage regulator circuit according to the first voltage, so that the output voltage of the linear voltage regulator circuit is maintained at a target voltage;

[0044] The feedback module is used to divide the output voltage of the linear voltage stabilization circuit and output the feedback voltage obtained by the voltage division to the input end of the operational amplifier module.

[0045] In one of the embodiments, the power module includes an output power tube, and the feedback module includes two voltage-dividing resistors;

[0046] The control end of the output power tube is connected to the output end of the operational amplifier module, and the first end is connected to the power supply voltage;

[0047] The two voltage-dividing resistors are connected in series, and one end of the series connection is connected to the second end of the output power tube to serve as the output end of the linear voltage stabilizing circuit; the other end of the series connection is connected to the ground wire;

[0048] The middle node of the two voltage-dividing resistors is connected to the input end of the operational amplifier module for outputting the feedback voltage.

[0049] In a third aspect, the present application further provides a chip, comprising: the linear voltage stabilization circuit described in the second aspect.

[0050] The above operational amplifier module, linear voltage regulator circuit and chip have at least the following advantages:

[0051] The present application provides a line loss compensation unit in the operational amplifier module, which can detect changes in the load current of the linear regulator and provide compensation current to the load module according to the changes, so as to increase the output voltage of the linear regulator, reduce the impact of the voltage drop formed by the transmission path, and improve the accuracy of the output voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0054] Figure 1 It is a schematic diagram of the structure of the LDO circuit in the traditional technology;

[0055] Figure 2 is a structural block diagram of an operational amplifier module in one embodiment;

[0056] Figure 3 is a structural block diagram of an operational amplifier module in another embodiment;

[0057] Figure 4 is a schematic diagram of the structure of an operational amplifier module in one embodiment;

[0058] Figure 5 for Figure 4 Schematic diagram of simulation results of the operational amplifier module;

[0059] Figure 6 is a schematic structural diagram of a line loss compensation unit in another embodiment;

[0060] Figure 7 is a structural block diagram of a linear voltage stabilizing circuit in one embodiment;

[0061] Figure 8 FIG. 4 is a structural block diagram of a chip in one embodiment.

[0062] Description of reference numerals:

[0063] 100, operational amplifier module; 200, power module; 300, feedback module;

[0064] 110, input stage unit; 120, load unit; 130, line loss compensation unit;

[0065] 111, current source subunit; 121, first load subunit; 122, second load subunit. DETAILED DESCRIPTION

[0066] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0067] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0068] In the case of using “including”, “having”, and “comprising” described herein, another component may be added unless a clear limiting term such as “only”, “consisting of”, etc. is used. Unless mentioned otherwise, a term in the singular form may include a plural form and should not be understood as being one in number.

[0069] It should be understood that although the terms "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element without departing from the scope of the present application.

[0070] In this application, unless otherwise clearly specified and limited, the terms "connected", "connection" and the like should be understood in a broad sense, for example, it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0071] See also Figure 2In some feasible embodiments, the present application provides an operational amplifier module 100, which is applied to a linear regulator and is disposed in the linear regulator. Specifically, it includes: an input stage unit 110, a load unit 120 and a line loss compensation unit 130.

[0072] The input stage unit 110 includes a first input terminal, a second input terminal, a first output terminal, and a second output terminal. The first input terminal of the input stage unit 110 is connected to the input reference voltage VREF, the second input terminal is connected to the input feedback voltage VFB, and the first output terminal and the second output terminal are respectively connected to the input terminal of the load unit 120. The input stage unit 110 in this embodiment is used to obtain the difference information of the input reference voltage and the feedback voltage according to the input reference voltage and the feedback voltage, and transmit the difference information to the load unit 120 through the first output terminal and the second output terminal. Among them, the first input terminal and the second input terminal of the input stage unit 110 also serve as the first input terminal and the second input terminal of the operational amplifier module 100.

[0073] The load unit 120 includes a first input terminal, a second input terminal and an output terminal. The first input terminal of the load unit 120 is connected to the first output terminal of the input stage unit 110, and the second input terminal is connected to the second output terminal of the input stage unit 110. The output terminal of the load unit 120 serves as the output terminal of the operational amplifier module 100, and is used to generate a first voltage VPG based on the above-mentioned difference information. Among them, the first voltage represents the output voltage of the operational amplifier module 100. When current flows through the load unit 120, the load unit 120 will generate a first voltage. Furthermore, the first input terminal or the second input terminal of the load unit 120 is also connected to the output terminal of the line loss compensation unit 130, and is used to receive the compensation current input by the line loss compensation unit 130, and increase the output voltage of the linear regulator according to the compensation current.

[0074] The line loss compensation unit 130 includes an input terminal and an output terminal. The input terminal of the line loss compensation unit 130 is connected to the output terminal of the load unit 120, and is used to introduce a first voltage into the line loss compensation unit 130 to detect changes in the load current of the linear regulator. The output terminal of the line loss compensation unit 130 is connected to the third input terminal of the load unit 120, and is used to provide a compensation current to the load unit 120 according to changes in the load current, so as to increase the output voltage of the linear regulator when the load current is large, so that the voltage of the external load terminal connected to the linear regulator maintains the target voltage, thereby reducing the voltage drop effect formed by the transmission path and ensuring the accuracy of the output voltage.

[0075] In the above embodiment, the input stage unit 110 detects the voltage difference between the input reference voltage and the feedback voltage, and transmits the difference information between the two to the load unit 120, so that the load unit 120 outputs the first voltage according to the difference information. Further, the line loss compensation unit 130 can detect the change of the load current of the linear regulator according to the first voltage, and provide a compensation current to the load unit 120, so as to adjust the output voltage of the linear regulator to the target voltage when the load current is large. By adopting the above scheme, the output voltage of the linear regulator can be increased to reduce the voltage drop effect formed by the transmission path, thereby improving the accuracy of the output voltage.

[0076] See also Figure 3 Optionally, the line loss compensation unit 130 includes: a first transistor, which is a PMOS tube, denoted as MP1. The control end of the first transistor MP1 is connected to the output end of the load unit 120 as the input end of the line loss compensation unit 130, and is used to access the first voltage VPG. The first end of the first transistor MP1 is connected to the power supply voltage VDD, and the second end is connected to the third input end of the load unit 120 as the output end of the line loss compensation unit 130.

[0077] Optionally, the input stage unit 110 includes: a fourth transistor and a fifth transistor, wherein the fourth transistor and the fifth transistor are a pair of differential transistors, and both the fourth transistor and the fifth transistor are PMOS transistors, which are respectively denoted as MP2 and MP3.

[0078] The control end of the fourth transistor MP2 is connected to the reference voltage VREF as the first input end of the input stage unit 110. The control end of the fifth transistor MP3 is connected to the feedback voltage VFB as the second input end of the input stage unit 110. After the first end of the fourth transistor MP2 and the first end of the fifth transistor MP3 are connected, they are connected to the power supply voltage VDD as the third input end of the input stage unit 110. The second end of the fourth transistor MP2 is connected to the first input end of the load unit 120 as the first output end of the input stage unit 110. The second end of the fifth transistor MP3 is connected to the second input end of the load unit 120 as the second output end of the input stage unit 110.

[0079] See also Figure 4 Optionally, the input stage unit 110 further includes: a current source subunit 111 .

[0080] The current source subunit 111 includes an input terminal and an output terminal. The input terminal of the current source subunit 111 is connected to the input bypass signal VBP, and the output terminal is connected to the first terminal of the fourth transistor MP2 and the first terminal of the fifth transistor MP3 of the input stage unit 110. It is used to turn on or off the connection channel between the power supply voltage and the input stage unit 110 according to the input bypass signal VBP, and provide a stable working current signal for the input stage unit 110.

[0081] See also Figure 3 Optionally, the current source subunit 111 includes: a sixth transistor, which is a PMOS tube, denoted as MP6. The control end of the sixth transistor MP6 is connected to the bypass signal, and the first end is connected to the power supply voltage VDD. The second end of the sixth transistor MP6 is connected to the third input end of the input stage unit 110 as the output end of the current source subunit 111.

[0082] Optionally, the load unit 120 includes a first load subunit 121 and a second load subunit 122 .

[0083] The first load subunit 121 includes a seventh transistor and an eighth transistor, wherein the seventh transistor and the eighth transistor are both PMOS transistors, which are respectively denoted as MP4 and MP5.

[0084] The second load subunit 122 includes a ninth transistor, a tenth transistor, an eleventh transistor and a twelfth transistor, wherein the ninth transistor, the tenth transistor, the eleventh transistor and the twelfth transistor are all NMOS transistors, which are respectively denoted as MN1, MN2, MN3 and MN4.

[0085] After the control end of the seventh transistor MP4, the second end of the seventh transistor MP4 and the control end of the eighth transistor MP5 are connected, they are connected to the second end of the eleventh transistor MN3. The first end of the seventh transistor MP4 and the first end of the eighth transistor MP5 are connected to the power supply voltage VDD. After the second end of the eighth transistor MP5 is connected to the second end of the twelfth transistor MN4, it serves as the output end of the load unit 120 to output the first voltage VPG. After the control end of the ninth transistor MN1, the second end of the ninth transistor MN1 and the control end of the eleventh transistor MN3 are connected, they serve as the first input end of the load unit 120 and are connected to the first output end of the input stage unit 110; after the control end of the tenth transistor MN2, the second end of the tenth transistor MN2 and the control end of the twelfth transistor MN4 are connected, they serve as the second input end of the load unit 120 and are connected to the second output end of the input stage unit 110; the first ends of the ninth transistor MN1, the tenth transistor MN2, the eleventh transistor MN3 and the twelfth transistor MN4 are connected to the ground respectively.

[0086] In order to enable those skilled in the art to fully understand the present application, the following Figure 3 , the working principle of the operational amplifier module 100 with the above structure is described in detail.

[0087] Figure 3 The current i1 in the output terminal of the load unit 120 flows through the ninth transistor MN1, the eleventh transistor MN3, the seventh transistor MP4, and the eighth transistor MP5, and the current i2 flows through the tenth transistor MN2 and the twelfth transistor MN4 into the output terminal of the load unit 120, wherein, Figure 4 The ninth transistor MN1 and the eleventh transistor MN3 form a pair of current mirrors, the seventh transistor MP4 and the eighth transistor MP5 form a pair of current mirrors, and the tenth transistor MN2 and the twelfth transistor MN4 form a pair of current mirrors, wherein the ratio of the current mirrors formed by the ninth transistor MN1 and the eleventh transistor MN3, the tenth transistor MN2 and the twelfth transistor MN4 are all set to 1:K; the ratio of the current mirror formed by the seventh transistor MP4 and the eighth transistor MP5 is set to 1:1. When the line loss compensation unit 130 is not connected, according to the working principle of the operational amplifier, at this time VREF=VFB, i1=i2, the current flowing through the eighth transistor MP5 is K×i1, and the current flowing through the twelfth transistor MN4 is K×i2, then the output voltage VOUTpad of the linear regulator is VREF×(1+R1 / R2). In the case of a large load current, the actual output voltage expression at this time is: VOUT=VOUTpad-Iout×Rw.

[0088] When the line loss compensation unit 130 is connected, since the current i3 is added to the current i2, the current flowing through the eighth transistor MP5 is still K×i1, and the current flowing through the twelfth transistor MN4 becomes K×(i2+i3). According to the working principle of the operational amplifier, in order to make the current consistent, the feedback voltage VFB=VREF+ΔVREF at this time, and the output voltage of the linear regulator will become higher. At this time, VOUTpad= (VREF+ΔVREF) ×(1+R1 / R2), which is higher than the previous output voltage VREF×(1+R1 / R2).

[0089] When the load current is large, the actual output voltage expression is:

[0090] VOUT=VOUTpad-Iout×Rw= (VREF+ΔVREF) ×(1+R1 / R2)-Iout×Rw= VREF×(1+R1 / R2)+(ΔVREF×(1+R1 / R2)- Iout×Rw).

[0091] From the above expression, it can be seen that if ΔVREF×(1+R1 / R2)- Iout×Rw is closer to zero, the output voltage can be closer to the output voltage when the load current is small, thereby reducing the impact of the voltage drop formed by the transmission path and ensuring the accuracy of the output voltage.

[0092] in, Figure 4 The resistor R1, the resistor R2 and the impedance Rw corresponding to the bonding transmission line are all fixed values. At this time, there is a corresponding relationship between ΔVREF and the load current Iout.

[0093] Furthermore, since the Vgs and Vth of P0 and MP1 are the same, according to the current formula

[0094] (1)

[0095] You can get:

[0096] (2)

[0097] In addition, i1+i2=ib, i1=i2+i3, we can get i1=(ib+i3) / 2, i2=(ib-i3) / 2, then

[0098] (3)

[0099] Where ib is the current provided by the current source subunit, β is the current coefficient of the transistor, Vgs is the voltage between the gate and source of the transistor, and Vth is the threshold voltage of the transistor. From equation (3), it can be seen that there is a relationship between ΔVREF and Iout.

[0100] Therefore, after reasonably setting the parameters in the above expression, ΔVREF×(1+R1 / R2)- Iout×Rw can be satisfied to be close to zero, thereby reducing the impact of the voltage drop formed by the transmission path and ensuring the accuracy of the output voltage.

[0101] See also Figure 5 , Figure 5 The simulation results of the operational amplifier module 100 using the above structure. When the impedance Rw is 5 ohms, the Iout value range is 0-50mA, and the target value of the linear regulator output voltage is 3V, when the line loss compensation unit 130 is not connected, the actual output voltage VOUT_old of the linear regulator drops to 2.7V, and there is a large voltage drop. When the line loss compensation unit 130 is connected, the actual output voltage VOUT_patent of the linear regulator and the output voltage VOUTpad of the operational amplifier module 100 are almost the same as 3V. It can be seen that due to the compensation current of the line loss compensation unit 130, even when the load current is large, the output voltage drop is very small, meeting the accuracy requirements.

[0102] Optionally, the above Figure 3 The structure of the neutral line loss compensation unit 130 is only an example. In another embodiment, the same function can be achieved by changing the structure of the neutral line loss compensation unit 130 and the position where the current i3 is connected to the load unit 120.

[0103] See also Figure 6 , Figure 6 The line loss compensation unit 130 in the embodiment includes, in addition to the first transistor MP1, a second transistor and a third transistor. The second transistor and the third transistor are both NMOS transistors, which are respectively denoted as MN5 and MN6.

[0104] The control end of the first transistor MP1 is connected to the first voltage VPG as the input end of the line loss compensation unit 130, and the first end is connected to the power supply voltage VDD. The second end of the second transistor MN5, the control end of the second transistor MN5 and the control end of the third transistor MN6 are connected, and then connected to the second end of the first transistor MP1. The first end of the second transistor MN5 and the first end of the third transistor MN6 are connected to the ground line, and the second end of the third transistor MN6 is connected to the first input end of the load unit 120 as the output end of the line loss compensation unit 130.

[0105] With the above structure, the second transistor MN5 and the third transistor MN6 connect the current i3 of the first transistor MP1 to the current i1, so the current flowing into the ninth transistor MN1 becomes i1-i3, and the current flowing through the eighth transistor MP5 becomes K×(i1-i3), and the current flowing through the twelfth transistor MN4 is K×i2. Based on the same principle, the same result as the above formula (3) can be obtained.

[0106] Therefore, after reasonably setting the parameters in the above expression, ΔVREF×(1+R1 / R2)- Iout×Rw can be satisfied to be close to zero, thereby reducing the impact of the voltage drop formed by the transmission path and ensuring the accuracy of the output voltage.

[0107] The above operational amplifier module 100, wherein the input stage unit 110 is used to generate difference information related to the voltage difference between the input reference voltage and the feedback voltage, and transmit the difference information to the load unit 120, so that the load unit 120 outputs a first voltage according to the difference information; the line loss compensation unit 130 can detect the change of the load current of the linear regulator, and provide a compensation current to the load unit 120, so that the load unit 120 can increase the output voltage of the linear regulator according to the compensation current, so that the voltage of the external load end connected to the linear regulator maintains the target voltage. The above scheme can be used to increase the output voltage of the linear regulator to reduce the voltage drop effect formed by the transmission path, thereby improving the accuracy of the output voltage.

[0108] See also Figure 7 In some feasible embodiments, the embodiments of the present application further provide a linear voltage stabilization circuit, including: the operational amplifier module 100 provided in the above embodiments, as well as the power module 200 and the feedback module 300.

[0109] The operational amplifier module 100 is used to output a first voltage according to an input reference voltage and a feedback voltage; and detect changes in the load current of an external load of the linear voltage regulator circuit, and provide a compensation current for the load unit of the operational amplifier module according to the changes to increase the output voltage of the linear voltage regulator circuit so that the voltage of the external load terminal connected to the linear regulator maintains a target voltage.

[0110] The power module 200 is used to adjust the output current of the linear voltage regulator circuit according to the first voltage, so that the output voltage of the linear voltage regulator circuit is maintained at a target voltage.

[0111] The feedback module 300 is used to divide the output voltage of the linear voltage regulator circuit and output the feedback voltage obtained by the voltage division to the input end of the operational amplifier module 100 .

[0112] Specifically, the operational amplifier module 100 generates difference information related to the voltage difference according to the voltage difference between the input reference voltage and the feedback voltage, and generates a first voltage VPG after amplifying the difference information, and outputs the first voltage to the input end of the power module 200 to provide the power supply current for the power module 200, thereby adjusting the output current Iout and the output voltage VOUTpad of the linear voltage regulator circuit. At the same time, the feedback module 300 feeds back the feedback voltage obtained by the voltage division to the input end of the operational amplifier module 100. The above modules interact with each other, and by continuously adjusting the output current of the linear voltage regulator circuit, the linear voltage regulator circuit can maintain a stable output voltage when the external load and input voltage change. Furthermore, the operational amplifier module 100 also detects the change in the load current of the external load of the linear voltage regulator circuit, and generates a compensation current according to the change, and then adjusts the output current of the linear voltage regulator circuit, and finally adjusts the output voltage of the linear voltage regulator circuit, reduces the voltage drop effect formed by the transmission path, and improves the accuracy of the output voltage.

[0113] See also Figure 3 and Figure 6 Optionally, the power module 200 includes an output power tube P0, and the feedback module 300 includes two voltage-dividing resistors. Among them, the control end of the output power tube P0 is connected to the output end of the operational amplifier module 100, and the first end is connected to the power supply voltage VDD. The two voltage-dividing resistors are connected in series, and after one end of the series connection is connected to the second end of the output power tube P0, it serves as the output end of the linear voltage stabilization circuit; the other end of the series connection is connected to the ground wire. The middle node of the two voltage-dividing resistors is connected to the input end of the operational amplifier module 100 for outputting a feedback voltage. The first voltage VPG output by the operational amplifier module 100 is input to the control end of the transistor P0 to control the conduction or cutoff of the transistor P0. At the same time, the voltage across the voltage-dividing resistor R2 is used as a feedback voltage and is connected back to the input end of the operational amplifier module 100.

[0114] In the above-mentioned linear voltage regulator circuit, the operational amplifier module 100 amplifies the difference information between the input reference voltage and the feedback voltage to generate a first voltage. The first voltage is used to provide a power supply current to the power module 200, thereby adjusting the output voltage of the linear voltage regulator circuit to maintain it at a stable second target voltage. At the same time, the operational amplifier module 100 of the embodiment of the present application can also detect the change of the load current of the linear voltage regulator circuit, and increase the output voltage of the linear voltage regulator circuit by providing a compensation current, thereby reducing the voltage drop effect formed by the transmission path when the load current is large, and improving the accuracy of the output voltage.

[0115] See also Figure 8 In some feasible embodiments, the present application also provides a chip, including: the linear voltage regulator circuit provided in the above embodiments.

[0116] A linear voltage stabilizing circuit, the output end of which is connected to the corresponding pin of the chip through a bonding wire, and an external load is connected to the pin. The linear voltage stabilizing circuit of the embodiment of the present application is used to provide a stable output voltage VOUT for the external load according to the input voltage signal. When the load current of the external load is large, a compensation current can be generated inside the linear voltage stabilizing circuit to increase the output voltage of the linear voltage stabilizing circuit, thereby offsetting the situation in which the output voltage is reduced due to the impedance of the bonding wire in the transmission path, thereby improving the accuracy of the output voltage. Among them, the input voltage signal includes a reference voltage and a feedback voltage.

[0117] The above chip has a built-in linear voltage regulator circuit, which can detect changes in the load current of the linear voltage regulator circuit and increase the output voltage of the linear voltage regulator circuit by providing a compensation current, thereby reducing the impact of the voltage drop formed on the transmission path when the load current is large, thereby improving the accuracy of the output voltage.

[0118] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0119] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the present application. It should be noted that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. An operational amplifier module, characterized in that: Applied to linear regulator, the module includes: The input stage unit is used to obtain the difference information between the input reference voltage and the feedback voltage according to the input reference voltage and the feedback voltage; A load unit, configured to generate a first voltage based on the difference information; wherein the first voltage represents an output voltage of the operational amplifier module; The line loss compensation unit is used to detect the change of the load current of the linear regulator according to the first voltage, and provide a compensation current for the load unit according to the change to increase the output voltage of the linear regulator so that the voltage of the external load terminal connected to the linear regulator maintains the target voltage.

2. The operational amplifier module according to claim 1, characterized in that: The line loss compensation unit includes: a first transistor; The control terminal of the first transistor is connected to the first voltage, the first terminal is connected to the power supply voltage, and the second terminal is connected to the load unit; Wherein, the first transistor is a PMOS transistor.

3. The operational amplifier module according to claim 1, characterized in that: The line loss compensation unit includes: a first transistor, a second transistor and a third transistor; The control end of the first transistor is connected to the first voltage, and the first end is connected to the power supply voltage; the second end of the second transistor, the control end of the second transistor and the control end of the third transistor are connected, and then connected to the second end of the first transistor; The first end of the second transistor and the first end of the third transistor are connected to the ground line, and the second end of the third transistor is connected to the load unit; The first transistor is a PMOS transistor, and the second transistor and the third transistor are NMOS transistors.

4. The operational amplifier module according to claim 2 or 3, characterized in that: The input stage unit comprises: a fourth transistor and a fifth transistor; The control terminal of the fourth transistor is used as the first input terminal of the input stage unit and is connected to the reference voltage; The control terminal of the fifth transistor serves as the second input terminal of the input stage unit and is connected to the feedback voltage; After the first end of the fourth transistor and the first end of the fifth transistor are connected, the third input end of the input stage unit is connected to the power supply voltage; The second end of the fourth transistor serves as the first output end of the input stage unit and is connected to the first input end of the load unit; The second end of the fifth transistor serves as the second output end of the input stage unit and is connected to the second input end of the load unit; Wherein, the fourth transistor and the fifth transistor are PMOS transistors.

5. The operational amplifier module according to claim 4, characterized in that: The input stage unit also includes: The current source subunit is used to connect or disconnect the connection channel between the power supply voltage and the input stage unit according to the input bypass signal, so as to provide a current signal for the input stage unit.

6. The operational amplifier module according to claim 5, characterized in that: The current source subunit comprises: a sixth transistor; The control terminal of the sixth transistor is connected to the bypass signal, and the first terminal is connected to the power supply voltage; The second end of the sixth transistor serves as the output end of the current source sub-unit and is connected to the third input end of the input stage unit.

7. The operational amplifier module according to claim 2 or 3, characterized in that: The load unit includes a first load subunit and a second load subunit; the first load subunit includes a seventh transistor and an eighth transistor, and the second load subunit includes a ninth transistor, a tenth transistor, an eleventh transistor and a twelfth transistor; The control end of the seventh transistor, the second end of the seventh transistor and the control end of the eighth transistor are connected, and then connected to the second end of the eleventh transistor; The first end of the seventh transistor and the first end of the eighth transistor are connected to the power supply voltage; After the second end of the eighth transistor is connected to the second end of the twelfth transistor, the second end serves as the output end of the load unit to output the first voltage; After the control end of the ninth transistor, the second end of the ninth transistor and the control end of the eleventh transistor are connected, they serve as the first input end of the load unit and are connected to the first output end of the input stage unit; After the control end of the tenth transistor, the second end of the tenth transistor and the control end of the twelfth transistor are connected, they serve as the second input end of the load unit and are connected to the second output end of the input stage unit; First ends of the ninth transistor, the tenth transistor, the eleventh transistor and the twelfth transistor are respectively connected to ground lines.

8. A linear voltage stabilizing circuit, characterized in that: The circuit comprises: The operational amplifier module according to any one of claims 1 to 7, configured to output a first voltage according to an input reference voltage and a feedback voltage, and detect a change in a load current of an external load of the linear voltage regulator circuit, provide a compensation current for a load unit of the operational amplifier module according to the change, and increase the output voltage of the linear voltage regulator circuit so that the voltage of an external load terminal connected to the linear voltage regulator maintains a target voltage; a power module, configured to adjust an output current of the linear voltage regulator circuit according to the first voltage, so that the output voltage of the linear voltage regulator circuit is maintained at a target voltage; The feedback module is used to divide the output voltage of the linear voltage stabilization circuit and output the feedback voltage obtained by the voltage division to the input end of the operational amplifier module.

9. The linear voltage stabilizing circuit according to claim 8, characterized in that: The power module includes an output power tube, and the feedback module includes two voltage-dividing resistors; The control end of the output power tube is connected to the output end of the operational amplifier module, and the first end is connected to the power supply voltage; The two voltage-dividing resistors are connected in series, and one end of the series connection is connected to the second end of the output power tube to serve as the output end of the linear voltage stabilizing circuit; the other end of the series connection is connected to the ground wire; The middle node of the two voltage-dividing resistors is connected to the input end of the operational amplifier module for outputting the feedback voltage.

10. A chip, characterized in that: include: The linear voltage stabilizing circuit according to claim 8 or 9.

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