Bandgap reference circuit

Abstract

This application discloses a bandgap reference circuit, relating to the field of integrated circuit technology, comprising a power supply circuit configured to output a first current having a first temperature index and a second current having a second temperature index; a first modulation sub-circuit coupled to the power supply circuit and configured to follow the first current to output a first current that gives the base-emitter voltage a first curvature; a second modulation sub-circuit coupled to the power supply circuit and configured to follow the first current to output a second current that gives the base-emitter voltage a first curvature; a conversion sub-circuit coupled to the first and second modulation sub-circuits and configured to convert the first current into a first voltage and the second current into a second voltage; and a summing sub-circuit coupled to the conversion sub-circuit and configured to output a reference voltage based on the first and second voltages; wherein, one of the first and second curvatures is greater than zero, and one of the first and second curvatures is less than zero.

Description

Technical Field

[0001] This application relates to the field of integrated circuit technology, and in particular to a bandgap reference circuit. Background Technology

[0002] In high-performance computing devices such as servers, the stability of the internal reference voltage is one of the core factors ensuring the server's operational stability and long-term reliability. For example, power management circuits provide core information for server power consumption control, fault warning, and energy efficiency optimization through current and / or voltage monitoring, and the stability of the reference voltage directly determines the accuracy of the power management circuit's current and / or voltage monitoring.

[0003] However, with the rapid development of cloud computing and big data technologies, servers, as central nodes for data processing, are experiencing continuously increasing demands for computing density and power consumption. This leads to a significant rise in the operating temperature of the entire machine, causing the reference voltage to drift due to the increased temperature. Therefore, an improved bandgap reference circuit is needed to solve the temperature drift problem of the reference voltage. Summary of the Invention

[0004] This application provides a bandgap reference circuit to at least address the problem of temperature drift of reference voltage in related technologies.

[0005] On one hand, a bandgap reference circuit is provided, comprising: a power supply circuit configured to output a first current having a first temperature index and a second current having a second temperature index; a first modulation sub-circuit coupled to the power supply circuit, the first modulation sub-circuit configured to follow the first current to output the first current giving a base-emitter voltage a first curvature; a second modulation sub-circuit coupled to the power supply circuit, the second modulation sub-circuit configured to follow the second current to output the second current giving a base-emitter voltage a second curvature; a conversion sub-circuit coupled to the first modulation sub-circuit and the second modulation sub-circuit, the conversion sub-circuit configured to convert the first current to a first voltage and the second current to a second voltage; and a summing sub-circuit coupled to the conversion sub-circuit, the summing sub-circuit configured to output a reference voltage based on the first voltage and the second voltage; wherein one of the first curvature and the second curvature is greater than zero, and one of the first curvature and the second curvature is less than zero.

[0006] In one feasible embodiment, the first modulator circuit includes a first transistor, and the second modulator circuit includes a second transistor; a first terminal of the first transistor is used to receive the first current, and a second terminal of the first transistor is used to output the first current, the first current causing the base-emitter voltage of the first transistor to have a first curvature; a first terminal of the second transistor is used to receive the second current, and a second terminal of the second transistor is used to output the second current, the second current causing the base-emitter voltage of the second transistor to have a second curvature; a control terminal of the second transistor is coupled to a control terminal of the first transistor; the sum of the first temperature index and the second temperature index is equal to twice the process constant of the first transistor, and the process constant of the first transistor is equal to the process constant of the second transistor.

[0007] In one feasible embodiment, both the first transistor and the second transistor are bipolar junction transistors.

[0008] In one feasible embodiment, the conversion sub-circuit includes a first conversion sub-circuit and a second conversion sub-circuit; the first conversion sub-circuit includes a first resistor, which is used to adjust the amplitude of the first voltage; the second conversion sub-circuit includes a second resistor, which is used to adjust the amplitude of the second voltage; wherein, the ratio of the resistance value of the first resistor to the resistance value of the second resistor is equal to the ratio of the first temperature index to the second temperature index.

[0009] In one feasible embodiment, the system further includes: a feedback subcircuit coupled to the first modulation subcircuit and the second modulation subcircuit, the feedback subcircuit being configured to output at least one of a first feedback signal and a second feedback signal based on the first current and the second current; a control subcircuit configured to output a control signal based on at least one of the first feedback signal and the second feedback signal; and the power supply circuit being further configured to receive the control signal and adjust at least one of the first temperature index and the second temperature index based on the control signal.

[0010] In one feasible embodiment, the feedback sub-circuit includes a first feedback sub-circuit, and the control signal includes a first control signal; the first feedback sub-circuit is coupled to a first modulation sub-circuit, and the first feedback sub-circuit is configured to output a first feedback signal based on the first current; a control sub-circuit is configured to receive the first feedback signal and output a first control signal based on the first feedback signal.

[0011] In one feasible embodiment, the first feedback sub-circuit includes: a first sampling unit coupled to the first modulation sub-circuit, the first sampling unit being configured to output a first sampling signal based on the first current and a first reference signal; and a first comparator coupled to the first sampling unit, the first comparator being configured to output the first feedback signal based on the first sampling signal and a first threshold signal.

[0012] In one feasible embodiment, the first comparator is configured to output the first feedback signal when the first sampled signal is greater than or equal to the first threshold signal.

[0013] In one feasible embodiment, the feedback sub-circuit further includes a second feedback sub-circuit, and the control signal further includes a second control signal: the second feedback sub-circuit is coupled to the second modulation sub-circuit, and the second feedback sub-circuit is configured to output a second feedback signal based on the second current; the control sub-circuit is further configured to receive the second feedback signal and output a second control signal based on the second feedback signal.

[0014] In one feasible embodiment, the second feedback sub-circuit includes: a second sampling unit coupled to the second modulation sub-circuit, the second sampling unit being configured to output a second sampling signal based on the second current and a second reference signal; and a second comparator coupled to the second sampling unit, the second comparator being configured to output the second feedback signal based on the second sampling signal and a first threshold signal.

[0015] In one feasible embodiment, the second comparator is configured to output the second feedback signal when the second sampled signal is less than or equal to the first threshold signal.

[0016] The bandgap reference circuit provided in this application adopts a symmetrical architecture based on the first transistor and the second transistor, and utilizes the characteristic that the curvature of the nonlinear part of the base-emitter voltage has opposite signs and complementary amplitudes under bias currents with different temperature indices. This allows for the physical cancellation of curvature errors at the summing sub-circuit. Therefore, it can effectively solve the temperature drift problem of traditional bandgap reference circuits and achieve the effect of outputting a high linearity reference voltage over a wide temperature range.

[0017] Furthermore, due to the introduction of a dynamic regulation mechanism consisting of a feedback sub-circuit and a control sub-circuit, the operating status of the first and second modulation sub-circuits can be monitored in real time and the temperature index of the current supplied to the electronic circuit can be automatically adjusted accordingly. Therefore, it can effectively cope with the circuit parameter mismatch caused by process deviations or drastic temperature changes, and achieve the goal of dynamically maintaining the optimal temperature index configuration under various operating conditions, thereby improving the stability and robustness of the reference voltage across the entire temperature range. Attached Figure Description

[0018] To more clearly illustrate the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of a bandgap reference circuit according to some embodiments;

[0020] Figure 2 for Figure 1 The circuit structure diagram of the first electronic power supply circuit;

[0021] Figure 3 for Figure 1 Circuit diagram of the second power supply circuit;

[0022] Figure 4 This is a schematic diagram of another bandgap reference circuit provided according to some embodiments;

[0023] Figure 5 This is a temperature characteristic curve of the base-emitter voltage of a bipolar junction transistor. Detailed Implementation

[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this application.

[0025] It should be noted that, in the description of this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. The terms "first," "second," etc., in this application are used to distinguish similar objects and are not used to describe a specific order or sequence.

[0026] In this document, the use of "configured to" implies open and inclusive language, which does not exclude devices configured to perform additional tasks or steps. In describing some embodiments, the term "coupled" and its derivative expressions may be used. For example, the term "coupled" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact. However, the term "coupled" may also refer to two or more components that do not have direct contact with each other but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the content of this document.

[0027] Unless the context otherwise requires, throughout the specification and claims, the term "comprise" and its other forms, such as the third-person singular "comprises" and the present participle "comprising," are interpreted as open-ended and encompassing, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiments," "example," "specific example," or "some examples," etc., are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this application. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples.

[0028] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this application, unless otherwise stated, "multiple" means two or more. The use of "based on" implies openness and inclusivity, because processes, steps, calculations, or other actions "based on" one or more of the stated conditions or values ​​may in practice be based on additional conditions or values ​​beyond those stated.

[0029] "At least one of A, B, and C" has the same meaning as "at least one of A, B, or C," both including the following combinations of A, B, and C: only A, only B, only C, a combination of A and B, a combination of A and C, a combination of B and C, and a combination of A, B, and C. "A and / or B" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural.

[0030] In this document, the transistor can be selected from a bipolar junction transistor (BJT) or a metal-oxide-semiconductor field-effect transistor (MOSFET). When the transistor is selected from a bipolar junction transistor, the first terminal, the second terminal, and the control terminal of the transistor are the collector, the emitter, and the base, respectively. When the transistor is selected from a metal-oxide-semiconductor field-effect transistor, the first terminal, the second terminal, and the control terminal of the transistor are the source, the drain, and the gate, respectively. Alternatively, the first terminal, the second terminal, and the control terminal of an exemplary transistor can also be the drain, the source, and the gate, respectively.

[0031] To enable those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] In high-performance computing devices such as servers, the stability of the internal reference voltage is one of the core factors ensuring the server's operational stability and long-term reliability. For example, power management circuits provide core information for server power consumption control, fault warning, and energy efficiency optimization through current and / or voltage monitoring, and the stability of the reference voltage directly determines the accuracy of the power management circuit's current and / or voltage monitoring.

[0033] However, with the rapid development of cloud computing and big data technologies, servers, as the central nodes of data processing, are experiencing a continuous increase in computing density and power consumption, leading to a significant rise in the operating temperature of the entire machine. This also causes the reference voltage to drift due to the increased temperature. For example, in an ideal analog-to-digital converter (ADC), the digital value is equal to the product of the ratio of the input voltage to the reference voltage and 2^N, where N is the number of bits in the ADC. The reference voltage is provided by a bandgap reference circuit. When the temperature fluctuates, the reference voltage also deviates due to temperature drift, resulting in deviations in the digital value of the ADC. This, in turn, affects the operational stability and long-term reliability of electronic devices using this ADC.

[0034] Against this backdrop, related technologies typically involve adding an independent high-precision power supply circuit to the outside of the chip to provide a reference voltage for the chip, or testing the chip during production to obtain a current-temperature curve, and then applying this curve to the internal calibration of the chip.

[0035] External independent power supply circuits not only increase costs and occupy more space, but also require additional power management and signal wiring, and introduce new noise coupling paths or parasitic parameters. The rationality and reliability of internal calibration data depend heavily on the number of samples and the division of temperature gradients. Although it can reduce the temperature drift of the reference voltage to some extent, it cannot guarantee good compensation for different batches of chips or chips in the same batch operating at different temperatures. In addition, related technologies are also difficult to deal with temperature drift caused by sudden changes in CPU load and device aging.

[0036] In view of this, this application provides a bandgap reference circuit, such as Figure 1 The diagram shown is a schematic representation of a bandgap reference circuit according to some embodiments. The bandgap reference circuit 100 includes a power supply circuit 110, a first modulation sub-circuit 121, a second modulation sub-circuit 122, a conversion sub-circuit 130, and a summing sub-circuit 140.

[0037] The power supply circuit 110 is configured to output a first current I1 having a first temperature index and a second current I2 having a second temperature index.

[0038] In some embodiments, the power supply circuit 110 includes a first power supply circuit 111 and a second power supply circuit 112, wherein the first power supply circuit 111 is configured to output a first current I1 having a first temperature index, and the second power supply circuit 112 is configured to output a second current I2 having a second temperature index.

[0039] In some embodiments, the power supply circuit 110 further includes a third power supply circuit 113, which is configured to output a first power supply voltage Vs1.

[0040] The first modulator circuit 121 is coupled to the power supply circuit 110 to receive the first current I1 output by the power supply circuit 110. The first modulator circuit 121 is configured to follow the first current I1 to output the first current I1 having a first curvature.

[0041] In some embodiments, the first modulator circuit 121 includes a first transistor Q1, a first terminal of the first transistor Q1 for receiving a first current I1, a second terminal of the first transistor Q1 for outputting a first current I1 with a first curvature, and a control terminal of the first transistor Q1 for receiving a first power supply voltage Vs1 output by the third power supply circuit 113.

[0042] The second modulator circuit 122 is coupled to the power supply circuit 110 to receive the second current I2 output by the power supply circuit 110. The second modulator circuit 122 is configured to follow the second current I2 to output a second current I2 having a second curvature. One of the first curvature and the second curvature is greater than zero, and the other of the first curvature and the second curvature is less than zero.

[0043] In some embodiments, the second modulator circuit 122 includes a second transistor Q2, a first terminal of the second transistor Q2 for receiving a second current I2, a second terminal of the second transistor Q2 for outputting a second current I2 having a second curvature, and a control terminal of the second transistor Q2 coupled to the control terminal of the first transistor Q1.

[0044] In some embodiments, the sum of the first temperature index and the second temperature index is equal to twice the process constant of the first transistor Q1, and the process constant of the first transistor Q1 is equal to the process constant of the second transistor Q2.

[0045] For example, both the first transistor Q1 and the second transistor Q2 are selected from bipolar junction transistors, and the first transistor Q1 and the second transistor Q2 are symmetrical transistors.

[0046] See Figure 5 This is a temperature characteristic curve of the base-emitter voltage of a bipolar junction transistor (BJT), where the horizontal axis represents temperature in degrees Celsius, and the vertical axis represents the base-emitter voltage (V). BE The unit is volt. (From) Figure 5 As can be seen, the bipolar junction transistor has a negative temperature characteristic, and the base-emitter voltage V0 BE It decreases as the temperature rises.

[0047] Specifically, the base-emitter voltage of the first transistor Q1

[0048]

[0049] in,

[0050]

[0051] For V BE The nonlinear part.

[0052] It is the bandgap voltage of the first transistor Q1 at an absolute temperature of 0K; η is the process constant, usually 3-4; k is the Boltzmann constant; q is the charge number; T0 is a constant; VBE is the voltage at absolute temperature T0; T is the absolute temperature; α is the temperature index of the collector current of the first transistor Q1. The second transistor Q2 is basically the same as the first transistor Q1, so it will not be described further.

[0053] The conversion sub-circuit 130 is coupled to the first modulation sub-circuit 121 and the second modulation sub-circuit 122 to receive a first current I1 with a first curvature output from the first modulation sub-circuit 121 and a second current I2 with a second curvature output from the second modulation sub-circuit 122. The conversion sub-circuit 130 is configured to convert the first current I1 into a first voltage V1 and the second current I2 into a second voltage V2.

[0054] In some embodiments, the conversion sub-circuit 130 includes a first conversion sub-circuit 131 and a second conversion sub-circuit 132. The first conversion sub-circuit 131 includes a first resistor R1, and the second conversion sub-circuit 132 includes a second resistor R2. A first terminal of the first resistor R1 is coupled to a second terminal of the first transistor Q1 to receive a first current I1 having a first curvature, and the second terminal of the first resistor R1 is used to output a first voltage V1. A first terminal of the second resistor R2 is coupled to a second terminal of the second transistor Q2 to receive a second current I2 having a second curvature, and the second terminal of the second resistor R2 is used to output a second voltage V2.

[0055] In some embodiments, the ratio of the resistance of the first resistor R1 to the resistance of the second resistor R2 is equal to the ratio of the first temperature constant to the second temperature constant.

[0056] The summing sub-circuit 140 is coupled to the conversion sub-circuit 130 to receive a first voltage V1 and a second voltage V2. The summing sub-circuit 140 is configured to output a reference voltage Vout based on the first voltage V1 and the second voltage V2.

[0057] For example, the reference voltage Vout is equal to the sum of the first voltage V1 and the second voltage V2.

[0058] In the bandgap reference circuit 100 provided in this embodiment, the first transistor Q1 operates under a strong PTAT (Proportional To Absolute Temperature) current, and its collector current Ic exhibits a temperature characteristic with a first temperature index of 5, meaning that Ic is positively correlated with the fifth power of the absolute temperature. The second transistor Q2 operates in a medium PTAT current region, and its collector current Ic corresponds to a second temperature index of 2, meaning that Ic is positively correlated with the square of the absolute temperature. The first transistor Q1 and the second transistor Q2 are coupled to the summing sub-circuit 140 through a first resistor R1 and a second resistor R2, respectively.

[0059] The first transistor Q1 and the second transistor Q2 are coupled to the summing sub-circuit 140 through the first resistor R1 and the second resistor R2, respectively. Considering that the process constant η of the transistor is usually between 3 and 4, under the first temperature index condition, the first current I1 output by the first transistor Q1 exhibits a negative curvature characteristic, that is, its base-emitter voltage V BE The nonlinear component in the transistor exhibits negative curvature; however, under the second temperature index condition, the second current I2 output by the second transistor Q2 displays positive curvature characteristics, i.e., its base-emitter voltage V... BE The nonlinear part has positive curvature.

[0060] Since the curvature characteristics of the first current I1 and the second current I2 are opposite, after they are converted into voltage and weighted by the first resistor R1 and the second resistor R2 respectively, the resulting first voltage V1 and second voltage V2 exhibit complementary characteristics in amplitude. Therefore, the first resistor R1 and the second resistor R2 not only perform the function of current-to-voltage conversion, but also play a role in regulating the amplitude of the first current I1 and the second current I2.

[0061] By properly configuring the first temperature index, the second temperature index, and the resistance ratio of the first resistor R1 to the second resistor R2, the base-emitter voltage V of the first transistor Q1 and the second transistor Q2 is made equal to... BE The nonlinear components in the summing circuit cancel each other out when superimposed at the summing sub-circuit 140, thereby eliminating curvature error at the physical level and ultimately obtaining a reference voltage Vout with highly linear characteristics.

[0062] The bandgap reference circuit 100 provided in this application embodiment effectively solves the curvature error problem existing in the bandgap reference voltage, and can achieve ultra-low temperature drift characteristics over a wide temperature range, especially significantly reducing the influence of high-order temperature drift. This circuit constructs a pair of symmetrically arranged transistors—namely, first transistor Q1 and second transistor Q2—with their control terminals connected in common and their second terminals output through first resistor R1 and second resistor R2 respectively. These transistors operate under bias currents with different temperature indices, utilizing their base-emitter voltage V... BE The opposite signs and complementary amplitudes of the curvature errors allow them to cancel each other out during voltage superposition in the summing circuit 140, thus eliminating the nonlinear temperature drift component at the physical level. This solution requires no adjustment to the layout of the bandgap reference circuit 100, does not rely on complex algorithm compensation, and does not sacrifice other system performance indicators.

[0063] The bandgap reference circuit 100 provided in this application embodiment implements its curvature compensation mechanism through a purely analog circuit architecture. This compensation process is completed entirely in the analog domain, without the need for any digital control or calibration circuitry, thus fundamentally avoiding the introduction of digital switching noise. This fundamental advantage of analog implementation gives the circuit a series of outstanding advantages, including intrinsically low noise, instantaneous response, simple structure, and low static power consumption.

[0064] For example, when the bandgap reference circuit 100 provided in the embodiments of this application is applied to an analog-to-digital converter circuit, it can effectively improve the output accuracy and long-term operational stability of the analog-to-digital converter circuit.

[0065] In some embodiments, Figure 1 The first power supply circuit 111 in the middle can be specifically implemented as follows: Figure 2 The first power supply circuit 111 is shown. Figure 2 for Figure 1 The circuit structure diagram of the first power supply circuit is shown. The first power supply circuit 111 includes a seventh current generation unit and a first current generation unit.

[0066] The seventh current generation unit is configured to output a seventh current Ip with a third temperature index, for example, the third temperature index is 1.

[0067] In some embodiments, the seventh current generation unit includes a third current source Is3, a fourth current source Is4, a first voltage-controlled current source G1, a second voltage-controlled current source G2, a third transistor Q3, a fourth transistor Q4, a third resistor R3, a fourth resistor R4, a seventh transistor M1, and an eighth transistor M2.

[0068] The first terminal of the third current source Is3 is used to output the third current I3, and the second terminal is grounded. The first terminal of the fourth current source Is4 is used to output the fourth current I4, and the second terminal is grounded.

[0069] The first terminal of the third transistor Q3 is coupled to the third current source Is3 to receive the third current I3, and the second terminal is grounded. The first terminal of the fourth transistor Q4 is coupled to the fourth current source Is4 to receive the fourth current I4, and the second terminal is grounded. The control terminals of the third transistor Q3 and the fourth transistor Q4 are coupled to the first node N1.

[0070] For example, both the third transistor Q3 and the fourth transistor Q4 are selected from bipolar junction transistors.

[0071] The first end of the third resistor R3 is coupled to the first node N1, and the second end of the third resistor R3 is grounded.

[0072] In this embodiment, the voltage of the first node N1 is positively correlated with the absolute temperature T. A first control terminal of the first voltage-controlled current source G1 is coupled to the first node N1 to receive the voltage of the first node N1, and a second control terminal is grounded. The first terminal of the first voltage-controlled current source G1 is used to output a first voltage-controlled current Ig1, and the second terminal is grounded. The first voltage-controlled current source G1 is configured to output the first voltage-controlled current Ig1 based on the voltage of the first node N1.

[0073] The first end of the fourth resistor R4 is coupled to the first end of the first voltage-controlled current source G1, and the second end of the fourth resistor R4 is grounded.

[0074] The first terminal of the seventh transistor M1 is coupled to the second node N2, the second terminal is grounded, and the control terminal is coupled to the first terminal of the fourth resistor R4. The first terminal of the eighth transistor M2 is coupled to the second node N2, the second terminal is grounded, and the control terminal is coupled to the first terminal of the fourth resistor R4.

[0075] The first control terminal of the second voltage-controlled current source G2 is coupled to the second node N2, and the second control terminal is grounded. The second terminal of the second voltage-controlled current source G2 is also grounded. The first terminal of the ninth transistor M3 is coupled to the first terminal of the second voltage-controlled current source G2, and the second terminal is grounded. The control terminal of the ninth transistor M3 is coupled to the first terminal of the ninth transistor M3.

[0076] The seventh transistor M1 and the eighth transistor M2 are configured to regulate the voltage of the second node N2 based on the voltage at the first end of the fourth resistor R4, and the second voltage-controlled current source G2 is configured to output the seventh current Ip based on the voltage of the second node N2.

[0077] The first current generating unit is coupled to the seventh current generating unit to receive the seventh current Ip. The first current generating unit is configured to output a first current I1 with a first temperature index based on the seventh current Ip with a third temperature index.

[0078] In some embodiments, the first current generation unit includes a tenth transistor M4, an eleventh transistor M5, a twelfth transistor M6, a thirteenth transistor M7, and a fourteenth transistor M8.

[0079] The control terminal of the tenth transistor M4 is coupled to the first terminal of the ninth transistor M3 to receive the seventh current Ip, and the second terminal of the tenth transistor M4 is grounded.

[0080] The control terminals of the eleventh transistor M5, twelfth transistor M6, thirteenth transistor M7, and fourteenth transistor M8 are all coupled to the control terminal of the tenth transistor M4. The second terminals of the eleventh transistor M5, twelfth transistor M6, thirteenth transistor M7, and fourteenth transistor M8 are all grounded. The first terminals of the eleventh transistor M5, twelfth transistor M6, thirteenth transistor M7, and fourteenth transistor M8 are all coupled to the first terminal of the tenth transistor M4 to output a first current I1 with a first temperature index.

[0081] For example, the seventh transistor M1 to the fourteenth transistor M8 are all selected from metal-oxide-semiconductor field-effect transistors.

[0082] The temperature dependence of the seventh current Ip with the third temperature parameter is amplified step by step by cascading transistors and resistors, thereby accurately generating the first current I1 with the first temperature parameter.

[0083] In some embodiments, Figure 1 The second power supply circuit 112 in the middle can be specifically implemented as follows: Figure 3 The second power supply circuit 112 is shown. Figure 3 for Figure 1 The circuit structure diagram of the second power supply circuit is shown. The second power supply circuit 112 includes a seventh current generation unit and a second current generation unit.

[0084] The seventh current generation unit is configured to output a seventh current Ip with a third temperature index, for example, the third temperature index is 1.

[0085] In some embodiments, the seventh current generation unit includes a fifth current source Is5, a sixth current source Is6, a third voltage-controlled current source G3, a fourth voltage-controlled current source G4, a fifth transistor Q5, a sixth transistor Q6, a fifth resistor R5, a sixth resistor R6, a fifteenth transistor M9, and a sixteenth transistor M10.

[0086] The first terminal of the fifth current source Is5 is used to output the fifth current I5, and the second terminal is grounded. The first terminal of the sixth current source Is6 is used to output the sixth current I6, and the second terminal is grounded.

[0087] The first terminal of the fifth transistor Q5 is coupled to the fifth current source Is5 to receive the fifth current I5, and the second terminal is grounded. The first terminal of the sixth transistor Q6 is coupled to the sixth current source Is6 to receive the sixth current I6, and the second terminal is grounded. The control terminals of the fifth transistor Q5 and the sixth transistor Q6 are coupled to the third node N3.

[0088] For example, both the fifth transistor Q5 and the sixth transistor Q6 are selected from bipolar junction transistors.

[0089] The first end of the fifth resistor R5 is coupled to the third node N3, and the second end of the fifth resistor R5 is grounded.

[0090] In this embodiment, the voltage of the third node N3 is positively correlated with the absolute temperature T. The first control terminal of the third voltage-controlled current source G3 is coupled to the third node N3 to receive its voltage, and the second control terminal is grounded. The first terminal of the third voltage-controlled current source G3 is used to output the third voltage-controlled current Ig3, and the second terminal is grounded. The third voltage-controlled current source G3 is configured to output the third voltage-controlled current Ig3 based on the voltage of the third node N3.

[0091] The first end of the sixth resistor R6 is coupled to the first end of the third voltage-controlled current source G3, and the second end of the sixth resistor R6 is grounded.

[0092] The first terminal of the fifteenth transistor M9 is coupled to the fourth node N4, the second terminal is grounded, and the control terminal is coupled to the first terminal of the sixth resistor R6. The first terminal of the sixteenth transistor M10 is coupled to the fourth node N4, the second terminal is grounded, and the control terminal is coupled to the first terminal of the sixth resistor R6.

[0093] The first control terminal of the fourth voltage-controlled current source G4 is coupled to the fourth node N4, the second control terminal is grounded, and the second terminal of the fourth voltage-controlled current source G4 is grounded. The first terminal of the seventeenth transistor M11 is coupled to the first terminal of the fourth voltage-controlled current source G4, the second terminal is grounded, and the control terminal of the seventeenth transistor M11 is coupled to the first terminal of the seventeenth transistor M11.

[0094] The fifteenth transistor M9 and the sixteenth transistor M10 are configured to regulate the voltage of the fourth node N4 based on the voltage at the first terminal of the sixth resistor R6, and the fourth voltage-controlled current source G4 is configured to output the seventh current Ip based on the voltage of the fourth node N4.

[0095] For example, the fifteenth transistor M9 and the sixteenth transistor M10 are both selected from metal-oxide-semiconductor field-effect transistors.

[0096] The second current generating unit is coupled to the seventh current generating unit to receive the seventh current Ip. The second current generating unit is configured to output a second current I2 with a second temperature index based on the seventh current Ip with a third temperature index.

[0097] In some embodiments, the second current generation unit includes an eighteenth transistor M12 and a nineteenth transistor M13.

[0098] The control terminal of the eighteenth transistor M12 is coupled to the first terminal of the seventeenth transistor M11 to receive the seventh current Ip, and the second terminal of the eighteenth transistor M12 is grounded.

[0099] The control terminal of the nineteenth transistor M13 is coupled to the control terminal of the eighteenth transistor M12, and the second terminal of the nineteenth transistor M13 is grounded. The first terminal of the nineteenth transistor M13 is coupled to the first terminal of the tenth transistor M4 to output a second current I2 with a second temperature index.

[0100] For example, the eighteenth transistor M12 and the nineteenth transistor M13 are both selected from metal-oxide-semiconductor field-effect transistors.

[0101] The temperature dependence of the seventh current Ip with the third temperature parameter is amplified step by step by cascading transistors and resistors, thereby accurately generating the second current I2 with the second temperature parameter.

[0102] In some embodiments, this application also provides a bandgap reference circuit 100 with adaptive bias adjustment function, such as... Figure 4 The diagram shown is a schematic representation of another bandgap reference circuit provided according to some embodiments.

[0103] The bandgap reference circuit 100 further includes a feedback sub-circuit 200 and a control sub-circuit 300. The feedback sub-circuit 200 is coupled to a first modulation sub-circuit 121 and a second modulation sub-circuit 122 to receive a first current I1 and a second current I2. The feedback sub-circuit 200 is configured to output at least one of a first feedback signal Vfb1 and a second feedback signal Vfb2 based on the first current I1 and the second current I2.

[0104] In some embodiments, the feedback sub-circuit 200 includes a first feedback sub-circuit 210, which is coupled to a first modulation sub-circuit 121 to receive a first current I1. The first feedback sub-circuit 210 is configured to output a first feedback signal Vfb1 based on the first current I1.

[0105] In this embodiment, the first feedback sub-circuit 210 includes a first sampling unit 211 and a first comparator 212. The first input terminal of the first sampling unit 211 is coupled to the second terminal of the first transistor Q1 to receive a first current I1, and the second input terminal of the first sampling unit 211 is used to receive a first reference signal Vref1. The first sampling unit 211 is configured to output a first sampling signal Vsen1 based on the first current I1 and the first reference signal Vref1.

[0106] The first input terminal of the first comparator 212 is coupled to the output terminal of the first sampling unit 211 to receive the first sampling signal Vsen1. The second input terminal of the first comparator 212 is used to receive the first threshold signal Vth1. The first comparator 212 is configured to output a first feedback signal Vfb1 based on the first sampling signal Vsen1 and the first threshold signal Vth1.

[0107] In this embodiment, the first comparator 212 is configured to output a first feedback signal Vfb1 when the first sampled signal Vsen1 is greater than or equal to the first threshold signal Vth1.

[0108] In some embodiments, the feedback sub-circuit 200 further includes a second feedback sub-circuit 220, which is coupled to the second modulation sub-circuit 122 to receive the second current I2, and is configured to output a second feedback signal Vfb2 based on the second current I2.

[0109] In this embodiment, the second feedback sub-circuit 220 includes a second sampling unit 221 and a second comparator 222. The first input terminal of the second sampling unit 221 is coupled to the second terminal of the second transistor Q2 to receive the second current I2, and the second input terminal of the second sampling unit 221 is used to receive the second reference signal Vref2. The second sampling unit 221 is configured to output a second sampling signal Vsen2 based on the second current I2 and the second reference signal Vref2.

[0110] The first input terminal of the second comparator 222 is coupled to the output terminal of the second sampling unit 221 to receive the second sampling signal Vsen2. The second input terminal of the second comparator 222 is used to receive the first threshold signal Vth1. The second comparator 222 is configured to output a second feedback signal Vfb2 based on the second sampling signal Vsen2 and the first threshold signal Vth1.

[0111] In this embodiment, the second comparator 222 is configured to output a second feedback signal Vfb2 when the second sampled signal Vsen2 is less than or equal to the first threshold signal Vth1.

[0112] For example, the first sampling unit 211 and the second sampling unit 221 are selected from differential amplifiers.

[0113] The control sub-circuit 300 is coupled to the feedback sub-circuit 200 to receive at least one of the first feedback signal Vfb1 and the second feedback signal Vfb2. The control sub-circuit 300 is configured to output a control signal based on at least one of the first feedback signal Vfb1 and the second feedback signal Vfb2.

[0114] In some embodiments, the control signal includes a first control signal Vc1 and / or a second control signal Vc2.

[0115] The power supply circuit 110 is also coupled to the control sub-circuit 300 to receive the control signal output by the control sub-circuit 300. The power supply circuit 110 is also configured to adjust at least one of the first temperature index and the second temperature index based on the control signal.

[0116] In some embodiments, see Figure 2 The third current I3 and / or the fourth current I4 of the first power supply circuit 111 receive the first control signal Vc1 output by the control sub-circuit 300 to adjust the third current I3 and / or the fourth current I4, thereby adjusting the first temperature index of the first current I1 output by the first power supply circuit 111.

[0117] In some embodiments, see Figure 3 The fifth current I5 and / or the sixth current I6 of the second power supply circuit 112 receive the second control signal Vc2 output by the control sub-circuit 300 to adjust the fifth current I5 and / or the sixth current I6, thereby adjusting the second temperature parameter of the second current I2 output by the second power supply circuit 112.

[0118] This embodiment of the application constructs a closed-loop control system by introducing a feedback sub-circuit 200 and a control sub-circuit 300. This system can monitor the curvature balance state of the first transistor Q1 and the second transistor Q2 in real time, and based on this monitoring result, dynamically fine-tune the output current of the first power supply circuit 111 and / or the second power supply circuit 112. This adaptive adjustment mechanism enables the bandgap reference circuit 100 to automatically track and lock the current parameter that optimizes the curvature error compensation, thereby effectively overcoming performance degradation caused by semiconductor process deviations or drastic changes in operating temperature, and significantly improving the robustness and applicability of the circuit.

[0119] The bandgap reference circuit provided in this application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only intended to help understand the method and core ideas of this application. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of this application.

Claims

1. A bandgap reference circuit, characterized in that, include: An electronic power supply circuit is configured to output a first current having a first temperature index and a second current having a second temperature index. A first modulator circuit, coupled to the power supply circuit, is configured to follow the first current to output the first current that gives the base-emitter voltage a first curvature; the first modulator circuit includes a first transistor. A second modulator circuit, coupled to the power supply circuit, is configured to follow the second current to output the second current that gives the base-emitter voltage a second curvature; the second modulator circuit includes a second transistor. A conversion sub-circuit, coupled to the first modulation sub-circuit and the second modulation sub-circuit, is configured to convert the first current into a first voltage and the second current into a second voltage; the conversion sub-circuit includes a first resistor and a second resistor, the first resistor being used to adjust the amplitude of the first voltage and the second resistor being used to adjust the amplitude of the second voltage; A summing sub-circuit, coupled to the conversion sub-circuit, is configured to output a reference voltage based on the first voltage and the second voltage; wherein... One of the first curvature and the second curvature is greater than zero, and the other of the first curvature and the second curvature is less than zero; The sum of the first temperature index and the second temperature index is equal to twice the first transistor process constant, and the first transistor process constant is equal to the second transistor process constant. The ratio of the resistance value of the first resistor to the resistance value of the second resistor is equal to the ratio of the first temperature index to the second temperature index.

2. The bandgap reference circuit according to claim 1, characterized in that, The first terminal of the first transistor is used to receive the first current, and the second terminal of the first transistor is used to output the first current. The first current causes the base-emitter voltage of the first transistor to have a first curvature. The first terminal of the second transistor is used to receive the second current, and the second terminal of the second transistor is used to output the second current. The second current causes the base-emitter voltage of the second transistor to have a second curvature. The control terminal of the second transistor is coupled to the control terminal of the first transistor.

3. The bandgap reference circuit according to claim 2, characterized in that, Both the first transistor and the second transistor are bipolar junction transistors.

4. The bandgap reference circuit according to claim 1, characterized in that, Also includes: A feedback sub-circuit, coupled to the first modulation sub-circuit and the second modulation sub-circuit, is configured to output at least one of a first feedback signal and a second feedback signal based on the first current and the second current. A control subcircuit configured to output a control signal based on at least one of the first feedback signal and the second feedback signal; The power supply circuit is also configured to receive the control signal and adjust at least one of the first temperature index and the second temperature index based on the control signal.

5. The bandgap reference circuit according to claim 4, characterized in that, The feedback sub-circuit includes a first feedback sub-circuit, and the control signal includes a first control signal; The first feedback sub-circuit is coupled to the first modulation sub-circuit, and the first feedback sub-circuit is configured to output a first feedback signal based on the first current. A control subcircuit, configured to receive the first feedback signal and output a first control signal based on the first feedback signal.

6. The bandgap reference circuit according to claim 5, characterized in that, The first feedback sub-circuit includes: A first sampling unit is coupled to the first modulation sub-circuit, and the first sampling unit is configured to output a first sampling signal based on the first current and the first reference signal; A first comparator is coupled to the first sampling unit and is configured to output the first feedback signal based on the first sampled signal and the first threshold signal.

7. The bandgap reference circuit according to claim 6, characterized in that, The first comparator is configured to output the first feedback signal when the first sampled signal is greater than or equal to the first threshold signal.

8. The bandgap reference circuit according to claim 4, characterized in that, The feedback sub-circuit further includes a second feedback sub-circuit, and the control signal further includes a second control signal: The second feedback sub-circuit is coupled to the second modulation sub-circuit, and the second feedback sub-circuit is configured to output a second feedback signal based on the second current; The control subcircuit is further configured to receive the second feedback signal and output a second control signal based on the second feedback signal.

9. The bandgap reference circuit according to claim 8, characterized in that, The second feedback sub-circuit includes: The second sampling unit is coupled to the second modulation sub-circuit and is configured to output a second sampling signal based on the second current and the second reference signal. A second comparator, coupled to the second sampling unit, is configured to output the second feedback signal based on the second sampled signal and the first threshold signal.

10. The bandgap reference circuit according to claim 9, characterized in that, The second comparator is configured to output the second feedback signal when the second sampled signal is less than or equal to the first threshold signal.

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