Band-gap reference circuit, chip and electronic equipment

Abstract

The utility model provides a band-gap reference circuit, a chip and electronic equipment, and belongs to the technical field of electronics. The band-gap reference circuit comprises a band-gap reference voltage generation module, a positive temperature coefficient current generation module, a negative temperature coefficient current generation module, a zero temperature coefficient current generation module and a current comparison module; the positive temperature coefficient current generation module is connected with the band-gap reference voltage generation module, the negative temperature coefficient current generation module is connected with the positive temperature coefficient current generation module, and the zero temperature coefficient current generation module is respectively connected with the positive temperature coefficient current generation module and the negative temperature coefficient current generation module; the first input end of the current comparison module is connected with the zero temperature coefficient current generation module, the second input end is connected with the positive temperature coefficient current generation module or the negative temperature coefficient current generation module, and the output end is connected with the band-gap reference voltage generation module. According to the invention, self-calibration of temperature compensation is carried out, and the problem of high temperature drift coefficient is reduced.

Description

Technical Field

[0001] The present application relates to the field of electronic technology, and in particular to a bandgap reference circuit, a chip and an electronic device. Background Art

[0002] Bandgap reference circuits are widely used in analog circuits. They can provide a voltage that is independent of process, voltage, and temperature. The reference voltage source in the bandgap reference circuit has become an indispensable basic circuit module for large-scale and ultra-large-scale basic circuits and all digital analog systems. The reference voltage source can be widely used in circuits such as high-precision comparators, A / D converters (Analog to Digital) and D / A converters (Digital to Analog), random dynamic memory, flash memory, and system integrated chips.

[0003] In the traditional first-order bandgap reference circuit, the basic idea is to use the resistor voltage and the emitter-base voltage of the PNP transistor to superimpose to obtain the bandgap reference voltage. The resistor voltage has a positive temperature characteristic, and the emitter-base voltage of the PNP transistor has a negative temperature characteristic, which makes the bandgap reference voltage have high performance.

[0004] However, the emitter-base voltage of the PNP transistor has a nonlinear relationship with temperature. The resistance voltage of the traditional first-order bandgap reference circuit cannot compensate for the temperature drift of the transistor. Therefore, the output voltage of the traditional first-order bandgap reference circuit has a high temperature drift coefficient, which greatly limits the application of the traditional first-order bandgap reference circuit in high-precision systems. Utility Model Content

[0005] In order to solve the problems of the prior art, the embodiments of the present application provide a bandgap reference circuit, chip and electronic device, which can perform self-calibration of temperature compensation, thereby alleviating the problem of high temperature drift coefficient of the traditional first-order bandgap reference circuit. The technical solution is as follows:

[0006] According to one aspect of the present application, a bandgap reference circuit is provided, the bandgap reference circuit comprising a bandgap reference voltage generation module, a positive temperature coefficient current generation module, a negative temperature coefficient current generation module, a zero temperature coefficient current generation module and a current comparison module;

[0007] Wherein, the second end of the positive temperature coefficient current generating module is connected to the first end of the bandgap reference voltage generating module, the first end of the negative temperature coefficient current generating module is connected to the first end of the positive temperature coefficient current generating module, and the first end of the zero temperature coefficient current generating module is connected to the first end of the positive temperature coefficient current generating module and the second end of the negative temperature coefficient current generating module respectively;

[0008] The first input terminal of the current comparison module is connected to the second terminal of the zero temperature coefficient current generation module, the second input terminal is connected to the second terminal of the positive temperature coefficient current generation module or the third terminal of the negative temperature coefficient current generation module, and the output terminal is connected to the second terminal of the bandgap reference voltage generation module.

[0009] According to another aspect of the present application, a chip is provided, comprising the above-mentioned bandgap reference circuit.

[0010] According to another aspect of the present application, an electronic device is provided, comprising the above-mentioned bandgap reference circuit.

[0011] In the present application, the bandgap reference circuit includes a bandgap reference voltage generation module, a positive temperature coefficient current generation module, a negative temperature coefficient current generation module, a zero temperature coefficient current generation module and a current comparison module. The zero temperature coefficient current generation module generates a zero temperature coefficient current based on the positive temperature coefficient current generated by the positive temperature coefficient current generation module and the negative temperature coefficient current generated by the negative temperature coefficient current generation module, and compares the positive temperature coefficient current or the negative temperature coefficient current with the zero temperature coefficient current through the current comparison module, thereby generating a temperature drift comparison result to adjust the bandgap reference voltage of the bandgap reference voltage generation module. The bandgap reference circuit provided in this embodiment can perform self-calibration of temperature compensation, so that the bandgap reference circuit can reduce the temperature influence on the bandgap reference voltage within a certain temperature range, thereby alleviating the problem of high temperature drift coefficient of the traditional first-order bandgap reference circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Further details, features and advantages of the present application are disclosed in the following description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0013] Figure 1 A schematic diagram of a conventional first-order bandgap reference circuit provided according to an exemplary embodiment of the present application is shown;

[0014] Figure 2 A schematic diagram of a bandgap reference circuit provided according to an exemplary embodiment of the present application is shown;

[0015] Figure 3 A schematic diagram of a zero temperature coefficient current generating module provided according to an exemplary embodiment of the present application is shown;

[0016] Figure 4 A schematic diagram of a zero temperature coefficient first current mirror module provided according to an exemplary embodiment of the present application is shown;

[0017] Figure 5 A schematic diagram of another zero temperature coefficient current generating module provided according to an exemplary embodiment of the present application is shown;

[0018] Figure 6 A schematic diagram of a negative temperature coefficient current generating module provided according to an exemplary embodiment of the present application is shown;

[0019] Figure 7 A schematic diagram of a subthreshold field effect transistor module provided according to an exemplary embodiment of the present application is shown;

[0020] Figure 8 A schematic diagram of a second negative temperature coefficient current mirror branch provided according to an exemplary embodiment of the present application is shown;

[0021] Fig. 9 A schematic diagram of a positive temperature coefficient current generating module provided according to an exemplary embodiment of the present application is shown;

[0022] Fig.10 A sixth positive temperature coefficient current mirror branch schematic diagram provided according to an exemplary embodiment of the present application is shown;

[0023] Fig.11 A schematic diagram of a bandgap reference voltage generation module provided according to an exemplary embodiment of the present application is shown;

[0024] Fig.12 A schematic diagram of a variable resistance unit provided according to an exemplary embodiment of the present application is shown;

[0025] Fig.13 A schematic diagram of a selector module provided according to an exemplary embodiment of the present application is shown;

[0026] Fig.14 A specific bandgap reference circuit provided according to an exemplary embodiment of the present application is shown.

[0027] In the figure,

[0028] 1. Bandgap reference voltage generation module; 11. Operational amplifier unit; 12. First positive temperature coefficient current generation branch; 13. Second positive temperature coefficient current generation branch; 14. Bandgap reference voltage generation branch; 2. Positive temperature coefficient current generation module; 21. Positive temperature coefficient current reference branch; 22. Fourth positive temperature coefficient current mirror branch; 23. Fifth positive temperature coefficient current mirror branch; 24. Sixth positive temperature coefficient current mirror branch; 3. Negative temperature coefficient current generation module; 31. Second positive temperature coefficient current mirror branch; 32. Third positive temperature coefficient current mirror branch; 33. Subthreshold field effect transistor module; 331. First subthreshold field effect transistor Unit; 332, second subthreshold field effect transistor unit; 34, negative temperature coefficient current reference branch; 35, second negative temperature coefficient current mirror branch; 4, zero temperature coefficient current generation module; 41, zero temperature coefficient first current mirror module; 411, first positive temperature coefficient current mirror branch; 412, first negative temperature coefficient current mirror branch; 413, zero temperature coefficient first reference branch; 414, zero temperature coefficient first mirror branch; 42, zero temperature coefficient second current mirror module; 421, zero temperature coefficient second reference branch; 422, zero temperature coefficient second mirror branch; 5, current comparison module; 51, current comparison unit; 52, selector module. DETAILED DESCRIPTION

[0029] The embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be construed as being limited to the embodiments described herein. Instead, these embodiments are provided to provide a more thorough and complete understanding of the present application. It should be understood that the drawings and embodiments of the present application are only for exemplary purposes and are not intended to limit the scope of protection of the present application.

[0030] The term "including" and its variations used in this document are open inclusions, that is, "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments". Relevant definitions of other terms will be given in the description below. It should be noted that the concepts of "first", "second", etc. mentioned in this application are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0031] It should be noted that the modifications of "one" and "plurality" mentioned in the present application are illustrative rather than restrictive, and those skilled in the art should understand that unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0032] The names of the messages or information exchanged between multiple devices in the embodiments of the present application are only used for illustrative purposes and are not used to limit the scope of these messages or information.

[0033] The present application embodiment provides a bandgap reference circuit. Figure 1 Based on the traditional first-order bandgap reference circuit shown, the accuracy of the reference voltage is improved by using a self-calibration temperature compensation method. The bandgap reference circuit provided in this embodiment can be integrated in a chip or arranged in an electronic device.

[0034] like Figure 1 In the conventional first-order bandgap reference circuit shown in FIG. 1 , the resistors R5 and R6 are made of the same material, the PMOS tube (Positive channel Metal Oxide Semiconductor) M1 and the PMOS tube M2 have the same channel width-to-length ratio, the emitter area of ​​the PNP transistor Q4 is N times the emitter area of ​​the PNP transistor Q5, and the low-frequency gain Ad of the amplifier A1 is Ad>>1, then the drain current l1 of the PMOS tube M1 is Where q is the electron charge, k is the Boltzmann constant, and T is the absolute temperature. PMOS tube M3 and PMOS tube M2 have the same channel width-to-length ratio, so the output voltage V of the bandgap reference circuit is REF for Among them, V EB6 It is the emitter-base voltage of the PNP transistor Q6. By optimizing the resistance values ​​of resistors R5 and R6 and parameter N, a reference voltage V with zero temperature drift characteristics can be obtained within a certain temperature range. REF .

[0035] Since V EB6 It has temperature nonlinearity, so Figure 1 The output voltage of the conventional first-order bandgap reference circuit shown in FIG. 1 has a high temperature drift coefficient, which greatly limits the application of the conventional first-order bandgap reference circuit in high-precision systems. Based on this, the present application proposes the following Figure 2 The bandgap reference circuit shown.

[0036] Reference Figure 2 The bandgap reference circuit shown may include a bandgap reference voltage generating module 1 , a positive temperature coefficient current generating module 2 , a negative temperature coefficient current generating module 3 , a zero temperature coefficient current generating module 4 and a current comparing module 5 .

[0037] Wherein, the second end of the positive temperature coefficient current generating module 2 is connected to the first end of the bandgap reference voltage generating module 1, the first end of the negative temperature coefficient current generating module 3 is connected to the first end of the positive temperature coefficient current generating module 2, and the first end of the zero temperature coefficient current generating module 4 is connected to the first end of the positive temperature coefficient current generating module 2 and the second end of the negative temperature coefficient current generating module 3 respectively;

[0038] The first input terminal of the current comparison module 5 is connected to the second terminal of the zero temperature coefficient current generation module 4, the second input terminal is connected to the second terminal of the positive temperature coefficient current generation module 2 or the third terminal of the negative temperature coefficient current generation module 3, and the output terminal is connected to the second terminal of the bandgap reference voltage generation module 1.

[0039] The implementation principle can be as follows:

[0040] The positive temperature coefficient current generating module 2 can be used to generate multiple positive temperature coefficient currents;

[0041] The negative temperature coefficient current generating module 3 can be used to generate a negative temperature coefficient current related to the positive temperature coefficient current based on the positive temperature coefficient current;

[0042] The zero temperature coefficient current generating module 4 can be used to generate a zero temperature coefficient current according to the positive temperature coefficient current and the negative temperature coefficient current;

[0043] The current comparison module 5 can be used to compare the positive temperature coefficient current or the negative temperature coefficient current with the zero temperature coefficient current to generate a temperature drift comparison result;

[0044] The bandgap reference voltage generating module 1 can be used to generate a bandgap reference voltage based on the positive temperature coefficient current; whenever the temperature compensation condition is reached, the bandgap reference voltage is adjusted based on the temperature drift comparison result.

[0045] In a possible implementation, the positive temperature coefficient current generation module 2 can generate multiple positive temperature coefficient currents, which can be generated by resistors with positive temperature characteristics. Positive temperature coefficient current refers to a current that is proportional to absolute temperature (PTAT). The higher the absolute temperature, the greater the current; the lower the absolute temperature, the smaller the current.

[0046] The negative temperature coefficient current generating module 3 can receive or mirror the above-mentioned positive temperature coefficient current, so that the current with positive temperature characteristics related to the positive temperature coefficient current can flow through the negative temperature coefficient current generating module 3, and generate a negative temperature coefficient current through the current with positive temperature characteristics. At this time, since the negative temperature coefficient current is generated by the above-mentioned positive temperature coefficient current, the negative temperature coefficient current is correlated with the positive temperature coefficient current. The negative temperature coefficient current refers to a current that is inversely proportional to the absolute temperature (Complementary To Absolute Temperature, CTAT). The higher the absolute temperature, the smaller the current; the smaller the absolute temperature, the larger the current.

[0047] The zero temperature coefficient current generating module 4 can receive or mirror the above-mentioned positive temperature coefficient current, and receive or mirror the above-mentioned negative temperature coefficient current, and superimpose the positive temperature coefficient current and the negative temperature coefficient current through an appropriate superposition ratio, thereby generating a zero temperature coefficient current. The zero temperature coefficient current refers to a current that is approximately independent of absolute temperature, and the current floats within a certain range, which can be ignored.

[0048] The first input end of the current comparison module 5 can receive the above-mentioned zero temperature coefficient current, and the second input end can receive the above-mentioned positive temperature coefficient current or the above-mentioned negative temperature coefficient current, compare the zero temperature coefficient current with the positive temperature coefficient current, or compare the zero temperature coefficient current with the negative temperature coefficient current, and output the corresponding comparison result.

[0049] The bandgap reference voltage generation module 1 can generate the above-mentioned positive temperature coefficient current, and generate a bandgap reference voltage based on the positive temperature coefficient current through a resistor with positive temperature characteristics and a PNP transistor with negative temperature characteristics.

[0050] Moreover, whenever the temperature compensation condition is reached, for example, whenever the temperature rises by 27° C., the bandgap reference circuit provided in this embodiment can perform self-calibration. At this time, the bandgap reference voltage generation module 1 can receive the comparison result output by the current comparison module 5 as a control signal, and adjust the generated bandgap reference voltage for temperature compensation based on the control signal, so that the bandgap reference voltage is restored to the set value or near the set value.

[0051] Through the above modules (i.e., bandgap reference voltage generation module 1, positive temperature coefficient current generation module 2, negative temperature coefficient current generation module 3, zero temperature coefficient current generation module 4 and current comparison module 5), the bandgap reference circuit provided in this embodiment can perform self-calibration of temperature compensation, so that the bandgap reference circuit can reduce the temperature influence on the bandgap reference voltage within a certain temperature range, and alleviate the problem of high temperature drift coefficient of the above traditional first-order bandgap reference circuit. In addition, the above modules can be set in the same chip, that is, the above zero temperature coefficient current is the on-chip reference current, eliminating the requirement of off-chip reference current, and making it easier to set the bandgap reference circuit.

[0052] At the same time, the zero temperature coefficient current is correlated with both the positive temperature coefficient current and the negative temperature coefficient current, so that the current comparison module 5 can use any current of the positive temperature coefficient current and the negative temperature coefficient current to compare with the zero temperature coefficient current, which broadens the application scenarios of the bandgap reference circuit and can reduce power consumption.

[0053] Moreover, since it is a zero temperature coefficient current within the chip, which is obtained by superimposing the positive temperature coefficient current and the negative temperature coefficient current, the change trend of the corresponding zero temperature coefficient current is consistent with the change of the positive temperature coefficient current or the negative temperature coefficient current relative to the process. Therefore, the set temperature point is relatively constant and is less affected by process changes.

[0054] The zero temperature coefficient current generation module and its implementation principle are introduced below.

[0055] Optional, see Figure 3 The schematic diagram of the zero temperature coefficient current generating module is shown, the zero temperature coefficient current generating module 4 may include a zero temperature coefficient first current mirror module 41 and a zero temperature coefficient second current mirror module 42, the first end of the zero temperature coefficient first current mirror module 41 is respectively connected to the first end of the positive temperature coefficient current generating module 2 and the second end of the negative temperature coefficient current generating module 3, the first end of the zero temperature coefficient second current mirror module 42 is connected to the second end of the zero temperature coefficient first current mirror module 41, and the second end of the zero temperature coefficient second current mirror module 42 is connected to the first input end of the current comparison module 5.

[0056] The implementation principle can be as follows:

[0057] The zero temperature coefficient first current mirror module 41 can be used to mirror the positive temperature coefficient current generated by the positive temperature coefficient current generating module 2 and the negative temperature coefficient current generated by the negative temperature coefficient current generating module 3, and superimpose the positive temperature coefficient current and the negative temperature coefficient current obtained by the mirroring to generate a zero temperature coefficient current;

[0058] The zero temperature coefficient second current mirror module 42 can be used to mirror the zero temperature coefficient current generated by the zero temperature coefficient first current mirror module 41. The zero temperature coefficient current mirrored by the zero temperature coefficient second current mirror module 42 can be used to access the current comparison module 5.

[0059] In a possible implementation, based on the current mirror principle, the zero temperature coefficient first current mirror module 41 can mirror the positive temperature coefficient current generated by the positive temperature coefficient current generation module 2 and the negative temperature coefficient current generated by the negative temperature coefficient current generation module 3 to this module, and superimpose the positive temperature coefficient current and the negative temperature coefficient current obtained by mirroring according to a preset superposition ratio, thereby generating a zero temperature coefficient current. Similarly, the zero temperature coefficient second current mirror module 42 can mirror the zero temperature coefficient current to obtain at least one zero temperature coefficient current to be connected to the current comparison module 5.

[0060] Optional, see Figure 4 A schematic diagram of a zero temperature coefficient first current mirror module is shown, wherein the zero temperature coefficient first current mirror module 41 includes a first positive temperature coefficient current mirror branch 411 and a first negative temperature coefficient current mirror branch 412, wherein the first end of the first positive temperature coefficient current mirror branch 411 is connected to the first end of the positive temperature coefficient current generating module 2, the first end of the first negative temperature coefficient current mirror branch 412 is connected to the second end of the negative temperature coefficient current generating module 3, and the second end of the first positive temperature coefficient current mirror branch 411 is connected to the second end of the first negative temperature coefficient current mirror branch 412.

[0061] In a possible implementation, a positive temperature coefficient current reference branch 21 may be provided in the positive temperature coefficient current generating module 2, and the positive temperature coefficient current reference branch may form a set of current mirror circuits with the first positive temperature coefficient current mirror branch 411 in the zero temperature coefficient first current mirror module 41. When the positive temperature coefficient current flows through the positive temperature coefficient current reference branch 21, the first positive temperature coefficient current mirror branch 411 may obtain a corresponding positive temperature coefficient current by mirroring according to the current proportional relationship between the first positive temperature coefficient current mirror branch 411 and the positive temperature coefficient current reference branch 21.

[0062] Similarly, the negative temperature coefficient current generating module 3 may be provided with a negative temperature coefficient current reference branch 34, and the negative temperature coefficient current reference branch 34 may form a set of current mirror circuits with the first negative temperature coefficient current mirror branch 412 in the zero temperature coefficient first current mirror module 41. When the negative temperature coefficient current flows through the negative temperature coefficient current reference branch 34, the first negative temperature coefficient current mirror branch 412 may obtain a corresponding negative temperature coefficient current by mirroring according to the current ratio relationship between the first negative temperature coefficient current mirror branch 412 and the negative temperature coefficient current reference branch 34.

[0063] Furthermore, the positive temperature coefficient current mirrored by the first positive temperature coefficient current mirror branch 411 and the negative temperature coefficient current mirrored by the first negative temperature coefficient current mirror branch 412 can be superimposed at the output end where the two are connected (i.e., the connection between the second end of the first positive temperature coefficient current mirror branch 411 and the second end of the first negative temperature coefficient current mirror branch 412) to generate a zero temperature coefficient current.

[0064] Optionally, the first stacking ratio of the first positive temperature coefficient current mirror branch 411 may be a, and the second stacking ratio of the first negative temperature coefficient current mirror branch 412 may be b. The first stacking ratio a and the second stacking ratio b are adjustable.

[0065] In a possible implementation, the current flowing through the two branches can be adjusted by adjusting the current ratio of the first positive temperature coefficient current mirror branch 411 and the current ratio of the first negative temperature coefficient current mirror branch 412, thereby adjusting the first superposition ratio a and the second superposition ratio b. Assuming that the positive temperature coefficient current is I PTAT , the negative temperature coefficient current is I CTAT , then the zero temperature coefficient current I 0TC It can be expressed as I 0TC =aI PTAT +bI CTAT .

[0066] Optional, see Figure 5 As shown in the schematic diagram of the zero temperature coefficient current generating module, the zero temperature coefficient first current mirror module 41 also includes a zero temperature coefficient first reference branch 413 and a zero temperature coefficient first mirror branch 414, and the zero temperature coefficient second current mirror module 42 includes a zero temperature coefficient second reference branch 421 and a zero temperature coefficient second mirror branch 422.

[0067] The first end of the zero temperature coefficient first reference branch 413 is connected to the second end of the first positive temperature coefficient current mirror branch 411 and the second end of the first negative temperature coefficient current mirror branch 412, and the first end of the zero temperature coefficient first mirror branch 414 is connected to the second end of the zero temperature coefficient first reference branch 413;

[0068] The first end of the zero temperature coefficient second reference branch 421 is connected to the second end of the zero temperature coefficient first mirror branch 414, the first end of the zero temperature coefficient second mirror branch 422 is connected to the second end of the zero temperature coefficient second reference branch 421, and the second end of the zero temperature coefficient second mirror branch 422 is connected to the first input end of the current comparison module 5.

[0069] In a possible implementation, the zero temperature coefficient first reference branch 413 and the zero temperature coefficient first mirror branch 414 form a set of current mirror circuits. After the positive temperature coefficient current and the negative temperature coefficient current are superimposed to generate a zero temperature coefficient current, the zero temperature coefficient current can flow through the zero temperature coefficient first reference branch 413. Based on the current mirror principle, the zero temperature coefficient first mirror branch 414 can mirror to obtain a corresponding zero temperature coefficient current.

[0070] At this time, since the first end of the zero temperature coefficient second reference branch 421 is connected to the second end of the zero temperature coefficient first mirror branch 414, that is, the zero temperature coefficient second reference branch 421 and the zero temperature coefficient first mirror branch 414 belong to the same current loop, the zero temperature coefficient current obtained by mirroring the zero temperature coefficient first mirror branch 414 will flow through the zero temperature coefficient second reference branch 421. The zero temperature coefficient second reference branch 421 and the zero temperature coefficient second mirror branch 422 constitute a current mirror circuit. Based on the current mirror principle, the zero temperature coefficient second mirror branch 422 can mirror to obtain a corresponding zero temperature coefficient current, and the zero temperature coefficient current can be connected to the current comparison module 5 through the second end of the zero temperature coefficient second mirror branch 422.

[0071] Optionally, the zero temperature coefficient second current mirror module 42 includes at least one zero temperature coefficient second mirror branch 422, and the current comparison module 5 includes at least one current comparison unit 51, the current comparison unit 51 corresponds to the zero temperature coefficient second mirror branch 422 one by one, and the second end of the zero temperature coefficient second mirror branch 422 is connected to the first input end of the corresponding current comparison unit 51. As an example, if four current comparison units 51 are provided, four zero temperature coefficient second mirror branches 422 can be provided accordingly, and four zero temperature coefficient currents are output and connected to each current comparison unit 51 respectively.

[0072] The negative temperature coefficient current generation module and its implementation principle are introduced below.

[0073] Optional, see Figure 6 The schematic diagram of the negative temperature coefficient current generating module is shown, and the negative temperature coefficient current generating module 3 includes a second positive temperature coefficient current mirror branch 31, a third positive temperature coefficient current mirror branch 32, a subthreshold field effect transistor module 33 and a negative temperature coefficient current reference branch 34.

[0074] Wherein, the first end of the second positive temperature coefficient current mirror branch 31 is connected to the first end of the positive temperature coefficient current generating module 2, and the first end of the third positive temperature coefficient current mirror branch 32 is connected to the first end of the positive temperature coefficient current generating module 2;

[0075] A first end of the negative temperature coefficient current reference branch 34 is connected to a second end of the third positive temperature coefficient current mirror branch 32;

[0076] The first end of the subthreshold region field effect transistor module 33 is connected to the second end of the second positive temperature coefficient current mirror branch 31, the second end is connected to the second end of the third positive temperature coefficient current mirror branch 32, and the third end is connected to the second end of the negative temperature coefficient current reference branch 34;

[0077] The first end of the negative temperature coefficient current reference branch 34 is also connected to the first end of the zero temperature coefficient current generating module 4 .

[0078] In a possible implementation, a positive temperature coefficient current reference branch 21 may be provided in the positive temperature coefficient current generation module 2, and the positive temperature coefficient current reference branch 21 may form a current mirror circuit with the second positive temperature coefficient current mirror branch 31 and the third positive temperature coefficient current mirror branch 32, wherein the mirror branch may mirror the current flowing through the reference branch. When the positive temperature coefficient current flows through the positive temperature coefficient current reference branch 21, the second positive temperature coefficient current mirror branch 31 may mirror the corresponding positive temperature coefficient current according to the current proportional relationship between it and the positive temperature coefficient current reference branch 21. Similarly, the third positive temperature coefficient current mirror branch 32 may also mirror the corresponding positive temperature coefficient current according to the current proportional relationship between it and the positive temperature coefficient current reference branch 21.

[0079] The subthreshold field effect transistor module 33 can receive the positive temperature coefficient current output by the second positive temperature coefficient current mirror branch 31 and the positive temperature coefficient current output by the third positive temperature coefficient current mirror branch 32, and generate a negative temperature coefficient current through the subthreshold field effect transistor.

[0080] Since the third end of the subthreshold field effect transistor module 33 is connected to the second end of the negative temperature coefficient current reference branch 34, the negative temperature coefficient current generated by the subthreshold field effect transistor module 33 can flow through the negative temperature coefficient current reference branch 34, so that any mirror branch of the current mirror circuit formed with the negative temperature coefficient current reference branch 34 can mirror the negative temperature coefficient current, such as the first negative temperature coefficient current mirror branch 412 in the zero temperature coefficient current generation module 4.

[0081] Optional, see Figure 7The schematic diagram of the subthreshold region field effect transistor module is shown, and the subthreshold region field effect transistor module 33 may include a first subthreshold region field effect transistor unit 331, a second subthreshold region field effect transistor unit 332, a first transistor unit Q1 and a first resistor unit R1, and the control end of the first subthreshold region field effect transistor unit 331 is connected to the control end of the second subthreshold region field effect transistor unit 332. As a specific example: the control end of the first subthreshold region field effect transistor unit 331 may refer to the gate, the first end may refer to the source / drain, and the corresponding second end may refer to the drain / source; similarly, the control end of the second subthreshold region field effect transistor unit 332 may refer to the gate, the first end may refer to the source / drain, and the corresponding second end may refer to the drain / source; the first end of the first transistor unit Q1 may refer to the emitter / collector, the second end may refer to the base, and the corresponding third end may refer to the collector / emitter.

[0082] The first end of the first subthreshold region field effect tube unit 331 is connected to the second end of the second positive temperature coefficient current mirror branch 31, and the first end of the first subthreshold region field effect tube unit 331 is also connected to the second end of the first subthreshold region field effect tube unit 331;

[0083] The first end of the first transistor unit Q1 is connected to the third end of the first subthreshold region field effect transistor unit 331, the second end is connected to the third end of the first transistor unit Q1, and the third end is grounded;

[0084] The first end of the second subthreshold region field effect tube unit 332 is connected to the second end of the third positive temperature coefficient current mirror branch 32, and the second end is connected to the second end of the first subthreshold region field effect tube unit 331;

[0085] The first end of the first resistor unit R1 is connected to the third end of the second subthreshold region field effect transistor unit 332, the first end is also connected to the second end of the negative temperature coefficient current reference branch 34, and the second end is grounded.

[0086] Optionally, the current ratio between the second positive temperature coefficient current mirror branch 31 and the third positive temperature coefficient current mirror branch 32 is 1:n, and the size ratio between the first subthreshold region field effect tube unit 331 and the second subthreshold region field effect tube unit 332 is 1:m, and n and m are adjustable.

[0087] The implementation principle is as follows:

[0088] Assume that the subthreshold current of the first subthreshold field effect transistor unit 331 is I D , it can be expressed as:

[0089]

[0090] Wherein, W refers to the channel width of the first subthreshold region field effect transistor unit 331, L refers to the channel length of the first subthreshold region field effect transistor unit 331, V GS1 refers to the gate-source voltage of the first subthreshold region field effect transistor unit 331, V TH is the threshold voltage, V T refers to the temperature voltage equivalent, ε refers to the non-ideal constant, I D0 It refers to the characteristic current.

[0091] According to the above current ratio and size ratio, the subthreshold region current of the second subthreshold region field effect transistor unit 332 can be expressed as:

[0092]

[0093] The second end of the second subthreshold region field effect tube unit 332 is connected to the second end of the first subthreshold region field effect tube unit 331, that is, the gates of the two are connected, and the voltages here are equal, and the following relationship exists:

[0094] V EB1 +V GS1 =V GS2 +(nI PTAT +I CTAT )R1

[0095] Among them, V EB1 It refers to the emitter-base voltage of the first transistor unit Q1, nI PTAT It refers to the positive temperature coefficient current obtained by the third positive temperature coefficient current mirror branch 32, I CTAT It refers to the negative temperature coefficient current flowing through the negative temperature coefficient current reference branch 34 .

[0096] After finishing, we can get:

[0097]

[0098] By I CTAT It can be seen from the expression that I CTAT With positive temperature coefficient current I PTAT is related and decreases with increasing temperature.

[0099] Optionally, when the second input terminal of the current comparison module 5 is connected to the third terminal of the negative temperature coefficient current generation module 3, the negative temperature coefficient current generation module 3 also includes at least one second negative temperature coefficient current mirror branch 35, and the current comparison module 5 includes at least one current comparison unit 51, and the current comparison unit 51 corresponds to the second negative temperature coefficient current mirror branch 35. As an example, if four current comparison units 51 are provided, four second negative temperature coefficient current mirror branches 35 can be provided accordingly, and four negative temperature coefficient currents are output, which are respectively connected to each current comparison unit 51.

[0100] Reference Figure 8 The schematic diagram of the second negative temperature coefficient current mirror branch is shown, the first end of the second negative temperature coefficient current mirror branch 35 is connected to the first end of the negative temperature coefficient current reference branch 34, and the second end is connected to the second input end of the corresponding current comparison unit 51.

[0101] The positive temperature coefficient current generation module and its implementation principle are introduced below.

[0102] Optional, see Fig. 9 The schematic diagram of the positive temperature coefficient current generating module is shown. The positive temperature coefficient current generating module 2 may include a positive temperature coefficient current reference branch 21 , a fourth positive temperature coefficient current mirror branch 22 and a fifth positive temperature coefficient current mirror branch 23 .

[0103] Wherein, the second end of the positive temperature coefficient current reference branch 21 is connected to the first current input end of the bandgap reference voltage generation module 1;

[0104] A first end of the fourth positive temperature coefficient current mirror branch 22 is connected to a first end of the positive temperature coefficient current reference branch 21, and a second end is connected to a second current input end of the bandgap reference voltage generating module 1;

[0105] A first end of the fifth positive temperature coefficient current mirror branch 23 is connected to a first end of the positive temperature coefficient current reference branch 21 , and a second end of the fifth positive temperature coefficient current mirror branch 23 is connected to a third current input end of the bandgap reference voltage generation module 1 .

[0106] In a possible implementation, the bandgap reference voltage generation module 1 can be used to generate a positive temperature coefficient current. Based on the connection between the second end of the positive temperature coefficient current reference branch 21 and the first current input end of the bandgap reference voltage generation module 1, the positive temperature coefficient current can flow through the positive temperature coefficient current reference branch 21.

[0107] The positive temperature coefficient current reference branch 21 and the fourth positive temperature coefficient current mirror branch 22 and the fifth positive temperature coefficient current mirror branch 23 form a current mirror circuit. Based on the current mirror principle, the fourth positive temperature coefficient current mirror branch 22 and the fifth positive temperature coefficient current mirror branch 23 can mirror the positive temperature coefficient current flowing through the positive temperature coefficient current reference branch 21. Thus, at least two positive temperature coefficient currents can be generated to access the bandgap reference voltage generation module 1.

[0108] Optionally, when the second input terminal of the current comparison module 5 is connected to the second terminal of the positive temperature coefficient current generation module 2, the positive temperature coefficient current generation module 2 further includes at least one sixth positive temperature coefficient current mirror branch 24, and the current comparison module 5 includes at least one current comparison unit 51, and the current comparison unit 51 corresponds to the sixth positive temperature coefficient current mirror branch 24. As an example, if four current comparison units 51 are provided, four sixth positive temperature coefficient current mirror branches 24 may be provided accordingly, and four positive temperature coefficient currents may be output, which are respectively connected to each current comparison unit 51.

[0109] Reference Fig.10 The sixth positive temperature coefficient current mirror branch schematic diagram is shown, the first end of the sixth positive temperature coefficient current mirror branch 24 is connected to the first end of the positive temperature coefficient current reference branch 21, and the second end is connected to the second input end of the corresponding current comparison unit 51.

[0110] The bandgap reference voltage generation module and its implementation principle are introduced below.

[0111] Optional, see Fig.11 The schematic diagram of the bandgap reference voltage generation module is shown. The bandgap reference voltage generation module 1 includes an operational amplifier unit 11, a first positive temperature coefficient current generation branch 12, a second positive temperature coefficient current generation branch 13 and a bandgap reference voltage generation branch 14.

[0112] The first input terminal of the operational amplifier unit 11 is connected to the first current input terminal of the first positive temperature coefficient current generating branch 12, the second input terminal is connected to the second current input terminal of the second positive temperature coefficient current generating branch 13, and the output terminal is connected to the first terminal of the positive temperature coefficient current reference branch 21;

[0113] The first positive temperature coefficient current generating branch 12 includes a fourth resistor unit R4 and a second transistor unit Q2 connected in series, and the first current input terminal of the first positive temperature coefficient current generating branch 12 is also connected to the second terminal of the positive temperature coefficient current reference branch 21;

[0114] The second positive temperature coefficient current generating branch 13 includes a third transistor unit Q3, and the second current input terminal of the second positive temperature coefficient current generating branch 13 is also connected to the second terminal of the fourth positive temperature coefficient current mirror branch 22;

[0115] The bandgap reference voltage generating branch 14 includes a second resistance unit R2 and a variable resistance unit R3 connected in series. The third current input terminal of the bandgap reference voltage generating branch 14 is connected to the second end of the fifth positive temperature coefficient current mirror branch 23, and the current output terminal is connected to the second current input terminal of the positive temperature coefficient current second generating branch 13. The control terminal of the variable resistance unit R3 is connected to the output terminal of the current comparison module 5, wherein the bandgap reference voltage refers to the voltage at the third current input terminal of the bandgap reference voltage generating branch 14.

[0116] In a possible implementation, based on the principle of virtual short and virtual open, the voltages at the first input terminal and the second input terminal of the operational amplifier unit 11 can be considered equal, and the following relationship exists:

[0117] V EB3 =V EB2 +I PTAT R4

[0118] Among them, V EB3 Refers to the emitter-base voltage of the third transistor unit Q3, V EB2 It refers to the emitter-base voltage of the second transistor unit Q2. PTAT It refers to the positive temperature coefficient current output by the positive temperature coefficient current reference branch 21, and the fourth positive temperature coefficient current mirror branch 22 and the fifth positive temperature coefficient current mirror branch 23 can be mirrored in equal proportion, that is, the output current can be I PTAT .

[0119] Arranging the above formula gives:

[0120]

[0121] Here, c refers to the proportionality coefficient between the second triode unit Q2 and the third triode unit Q3.

[0122] Bandgap reference voltage V REF It can be equal to the sum of the emitter-base voltage of the third transistor unit Q3 and the voltage across the second resistor unit R2 and the variable resistor unit R3, and can be expressed as follows:

[0123]

[0124] From this expression, we can see that V EB3 With negative temperature characteristic, V TWith positive temperature characteristics, by adjusting the resistance of the variable resistor unit R3, V REF temperature drift.

[0125] Optionally, the variable resistance unit R3 may include at least one third resistance unit, and the current comparison module 5 includes at least one current comparison unit 51, and the current comparison unit 51 corresponds to the third resistance unit one by one. The third resistance unit is connected in parallel with the switch unit S, and the output end of the corresponding current comparison unit 51 is connected to the control end of the switch unit S. Fig.12 1. The schematic diagram of the variable resistance unit shown in FIG. 1 shows that if four current comparison units 51 are provided, the variable resistance unit R3 may include four third resistance units R 3-1 To R 3-4 , respectively connected in parallel with the four switch units S1 to S4. The comparison results output by the four current comparison units 51 can be used to control the switching off or on of the four switch units S1 to S4. On this basis, since the current comparison unit 51 corresponds to the third resistor unit one by one, the temperature compensation accuracy of the bandgap reference circuit provided in this embodiment is relatively high.

[0126] The self-calibration principle of temperature compensation is as follows:

[0127] Combined with the above positive temperature coefficient current I PTAT and negative temperature coefficient current I CTAT The expression of zero temperature coefficient current I can be obtained 0TC The expression is as follows:

[0128]

[0129] During the debugging phase of the circuit, the parameters a, b, m, and n can be adjusted to obtain a zero temperature coefficient current I that meets the current temperature conditions. 0TC .

[0130] In the application stage of the circuit, when temperature compensation is not performed, each switch unit S can be in an initial state (for example, all in a closed state), and the bandgap reference circuit can output a bandgap reference voltage that meets the set value, and the bandgap reference voltage may drift to a certain extent as the temperature changes. At this time, the negative temperature coefficient current generation module 3, the zero temperature coefficient current generation module 4 and the current comparison module 5 can be in a closed state.

[0131] Whenever the temperature compensation condition is reached, the negative temperature coefficient current generating module 3, the zero temperature coefficient current generating module 4 and the current comparison module 5 can be enabled, the bandgap reference voltage generating module 1 can receive the control signal output by the current comparison module 5, and control each switch unit S to turn off or close, so that the bandgap reference voltage can be restored to the set value or near the set value.

[0132] Optional, see Fig.13 As shown in the schematic diagram of the selector module, the second input end of the current comparison module 5 can also be provided with a selector module 52, the first input end of the selector module 52 is connected to the second end of the positive temperature coefficient current generating module 2, the second input end is connected to the third end of the negative temperature coefficient current generating module 3, and the output end is connected to the second input end of the current comparison module 5.

[0133] In a possible implementation, the selector module 52 may select the positive temperature coefficient current output by the positive temperature coefficient current generation module 2 or the negative temperature coefficient current output by the negative temperature coefficient current generation module 3 according to the selection signal to access the second input terminal of the current comparison module 5 .

[0134] Fig.14 A specific bandgap reference circuit is shown, which includes PMOS transistors MP1 to MP13, NMOS transistors (Negative channel Metal Oxide Semiconductor, N-channel Metal Oxide Semiconductor Field Effect Transistor) MN1 to MN4, resistors R1, R2, R 3-1 To R 3-k , R4, switches S1 to S k , PNP transistors Q1 to Q3, comparators C1 to Ck, inverters N1 to Nk, and operational amplifier OP.

[0135] MP1 to MP5 correspond to the above-mentioned positive temperature coefficient current generation module 2. MP1 corresponds to the above-mentioned positive temperature coefficient current reference branch 21, the source is used to receive the power supply voltage VDD, the drain is connected to one end of the resistor R4, and the gate is connected to the gate of MP2. MP2 corresponds to the above-mentioned fourth positive temperature coefficient current mirror branch 22, the source is used to receive the power supply voltage VDD, the drain is connected to the emitter of the transistor Q3, and the gate is connected to the gate of MP2. MP3 corresponds to the above-mentioned fifth positive temperature coefficient current mirror branch 23, the source is used to receive the power supply voltage VDD, the drain is connected to the resistor R 3-k The gate is connected to the gate of MP1. Any PMOS transistor such as MP4 to MP5 corresponds to the sixth positive temperature coefficient current mirror branch 24, the source is used to receive the power supply voltage VDD, the drain is connected to the non-inverting input terminal of the corresponding comparator, and the gate is connected to the gate of MP1. At this time, it can correspond to the situation where the second input terminal of the current comparison module 5 is connected to the second end of the positive temperature coefficient current generation module 2.

[0136] Operational amplifier OP, resistors R4, R2, R 3-1 To R 3-k, transistors Q2 and Q3 correspond to the above-mentioned bandgap reference voltage generation module 1. The non-inverting input terminal of the operational amplifier OP is connected to one end of the resistor R4, the inverting input terminal is connected to the emitter of the transistor Q3, and the output terminal is connected to the gate of MP1. The resistor R4 and the transistor Q2 are connected in series to form the above-mentioned positive temperature coefficient current first generation branch 12; one end of the resistor R2 is connected to the non-inverting input terminal of the operational amplifier OP, and the other end is connected to the emitter of the transistor Q2; the emitter of the transistor Q2 is connected to the other end of the resistor R4, and the collector and base are grounded. The transistor Q3 constitutes the above-mentioned positive temperature coefficient current second generation branch 13, the emitter of the transistor Q3 is connected to the drain of MP2, and the collector and base are grounded. Resistors R2, R 3-1 To R 3-k , switches S1 to S k , forming the bandgap reference voltage generating branch 14, wherein the resistor R2 corresponds to the second resistor unit R2, and the resistor R 3-1 To R 3-k , switches S1 to S k Corresponding to the above variable resistance unit R3. 3-k One end is connected to the drain of MP3, and resistors R2 and R 3-1 To R 3-k The other end of the resistor R2 is connected in series with the emitter of the transistor Q3. k With resistor R 3-1 To R 3-k They are connected in parallel one by one and are respectively controlled by control signals output by the current comparison module 5 composed of comparators C1 to Ck and inverters N1 to Nk.

[0137] PMOS transistors MP6, MP7, MP8, NMOS transistors MN1, MN2, transistor Q1, and resistor R1 correspond to the above-mentioned negative temperature coefficient current generation module 3. MP6 corresponds to the above-mentioned second positive temperature coefficient current mirror branch 31, with a source electrode used to receive the power supply voltage VDD, a drain electrode connected to the drain electrode of MN1, and a gate electrode connected to the gate electrode of MP1. MP7 corresponds to the above-mentioned third positive temperature coefficient current mirror branch 32, with a source electrode used to receive the power supply voltage VDD, a drain electrode connected to the drain electrode of MN2, and a gate electrode connected to the gate electrode of MP1. MP8 corresponds to the above-mentioned negative temperature coefficient current reference branch 34, with a source electrode used to receive the power supply voltage VDD, a drain electrode connected to one end of the resistor R1, and a gate electrode connected to the drain electrode of MP7. MN1, MN2, transistor Q1, and resistor R1 correspond to the above-mentioned subthreshold field effect transistor module 33; MN1 corresponds to the above-mentioned first subthreshold field effect transistor unit 331, the source is connected to the emitter of transistor Q1, the drain is connected to the drain of MP6, the gate is connected to the gate of MN2, and the gate is also connected to the drain of MN1; MN2 corresponds to the above-mentioned second subthreshold field effect transistor unit 332, the source is connected to one end of resistor R1, the drain is connected to the drain of MP7, and the gate is connected to the gate of MN1; transistor Q1 corresponds to the above-mentioned first transistor unit Q1, the emitter is connected to the source of MN1, and the collector and base are grounded; resistor R1 corresponds to the first resistor unit R1, one end is connected to the source of MN2 and the drain of MP8, and the other end is grounded.

[0138] PMOS transistors MP9, MP10, MP11, and NMOS transistors MN3 and MN4 correspond to the above-mentioned zero temperature coefficient current generation module 4. MP9, MP10, MN3, and MN4 constitute the above-mentioned zero temperature coefficient first current mirror module 41; MP9 corresponds to the above-mentioned first negative temperature coefficient current mirror branch 412, with a source electrode used to receive the power supply voltage VDD, a drain electrode connected to the drain electrode of MN3, and a gate electrode connected to the gate electrode of MP8; MP10 corresponds to the above-mentioned first positive temperature coefficient current mirror branch 411, with a source electrode used to receive the power supply voltage VDD, a drain electrode connected to the drain electrode of MN3, and a gate electrode connected to the gate electrode of MP1; MN3 corresponds to the above-mentioned zero temperature coefficient first reference branch 413, with a source electrode grounded, a drain electrode connected to the drain electrode of MP9 and MP10, a gate electrode connected to the gate electrode of MN4, and a gate electrode also connected to the drain electrode of MN3; MN4 corresponds to the above-mentioned zero temperature coefficient first mirror branch 414, with a source electrode grounded, a drain electrode connected to the drain electrode of MP11, and a gate electrode connected to the gate electrode of MN3. PMOS tubes such as MP11 to MP13 correspond to the above-mentioned zero temperature coefficient second current mirror module 42, MP11 corresponds to the above-mentioned zero temperature coefficient second reference branch 421, the source is used to receive the power supply voltage VDD, the drain is connected to the drain of MN4, and the gate is connected to the gate of PMOS tubes such as MP12 to MP13; any PMOS tube among the PMOS tubes such as MP12 to MP13 corresponds to the above-mentioned zero temperature coefficient second mirror branch 422, the source is used to receive the power supply voltage VDD, the drain is connected to the inverting input terminal of the corresponding comparator, and the gate is connected to the gate of MP11.

[0139] Comparators C1 to Ck and inverters N1 to Nk correspond to the current comparison module 5. Any comparator among comparators C1 to Cm corresponds to the current comparison unit 51, and the output end is connected to the input end of the corresponding inverter, and the output end of the inverter is connected to the corresponding switch.

[0140] Among them, the current I output by PMOS tubes such as MP4 to MP5 PT1 to I PTk That is, the positive temperature coefficient current obtained by the mirror image, the current I output by the PMOS tubes such as MP12 to MP13 0TC1 to I 0TCk This is the zero temperature coefficient current obtained by mirroring. The current I output by MP6 PTAT The positive temperature coefficient current obtained by mirroring, the current nI output by MP7 PTAT This is another positive temperature coefficient current obtained by mirroring, and the mirror ratio between MP6 and MP7 is 1:n. CTAT is the generated negative temperature coefficient current, I 0TC is the generated zero temperature coefficient current.

[0141] The implementation principle is the same as above and will not be repeated here.

[0142] The embodiments of the present application can achieve the following beneficial effects:

[0143] (1) The bandgap reference circuit includes a bandgap reference voltage generation module, a positive temperature coefficient current generation module, a negative temperature coefficient current generation module, a zero temperature coefficient current generation module and a current comparison module. The zero temperature coefficient current generation module generates a zero temperature coefficient current based on the positive temperature coefficient current generated by the positive temperature coefficient current generation module and the negative temperature coefficient current generated by the negative temperature coefficient current generation module, and compares the positive temperature coefficient current or the negative temperature coefficient current with the zero temperature coefficient current through the current comparison module, thereby generating a temperature drift comparison result to adjust the bandgap reference voltage of the bandgap reference voltage generation module. The bandgap reference circuit provided in this embodiment can perform self-calibration of temperature compensation, so that the bandgap reference circuit can reduce the temperature influence on the bandgap reference voltage within a certain temperature range, thereby alleviating the problem of high temperature drift coefficient of the traditional first-order bandgap reference circuit.

[0144] (2) The above modules can be arranged in the same chip, that is, the above zero temperature coefficient current is an on-chip reference current, eliminating the requirement for an off-chip reference current and making it easier to set up a bandgap reference circuit.

[0145] (3) The zero temperature coefficient current is correlated with both the positive temperature coefficient current and the negative temperature coefficient current, so that the current comparison module can use any current of the positive temperature coefficient current and the negative temperature coefficient current to compare with the zero temperature coefficient current, which broadens the application scenarios of the bandgap reference circuit and can reduce power consumption.

[0146] (4) The bandgap reference circuit provided in this embodiment can use the existing transistors in the traditional first-order bandgap reference circuit, eliminating the need for additional transistors.

[0147] (5) The bandgap reference circuit provided in this embodiment is a first-order structure and does not require the design of a complex high-order temperature compensation circuit, thereby eliminating structural complexity and saving area.

[0148] The exemplary embodiment of the present application also provides a chip, including the bandgap reference circuit provided by the embodiment of the present application. The bandgap reference circuit provided by the embodiment can perform self-calibration of temperature compensation, so that the bandgap reference circuit can reduce the temperature influence on the bandgap reference voltage within a certain temperature range, alleviate the problem of high temperature drift coefficient of the traditional first-order bandgap reference circuit, and improve chip performance.

[0149] The exemplary embodiment of the present application also provides an electronic device, including the bandgap reference circuit provided by the embodiment of the present application. The bandgap reference circuit provided by the embodiment can perform self-calibration of temperature compensation, so that the bandgap reference circuit can reduce the temperature influence on the bandgap reference voltage within a certain temperature range, alleviate the problem of high temperature drift coefficient of the traditional first-order bandgap reference circuit, and improve the performance of the electronic device.

Claims

1. A bandgap reference circuit, characterized in that: The bandgap reference circuit comprises a bandgap reference voltage generation module, a positive temperature coefficient current generation module, a negative temperature coefficient current generation module, a zero temperature coefficient current generation module and a current comparison module; Wherein, the second end of the positive temperature coefficient current generating module is connected to the first end of the bandgap reference voltage generating module, the first end of the negative temperature coefficient current generating module is connected to the first end of the positive temperature coefficient current generating module, and the first end of the zero temperature coefficient current generating module is connected to the first end of the positive temperature coefficient current generating module and the second end of the negative temperature coefficient current generating module respectively; The first input terminal of the current comparison module is connected to the second terminal of the zero temperature coefficient current generation module, the second input terminal is connected to the second terminal of the positive temperature coefficient current generation module or the third terminal of the negative temperature coefficient current generation module, and the output terminal is connected to the second terminal of the bandgap reference voltage generation module.

2. The bandgap reference circuit according to claim 1, characterized in that: The zero temperature coefficient current generating module comprises a zero temperature coefficient first current mirror module and a zero temperature coefficient second current mirror module, the first end of the zero temperature coefficient first current mirror module is respectively connected to the first end of the positive temperature coefficient current generating module and the second end of the negative temperature coefficient current generating module, the first end of the zero temperature coefficient second current mirror module is connected to the second end of the zero temperature coefficient first current mirror module, and the second end of the zero temperature coefficient second current mirror module is connected to the first input end of the current comparison module.

3. The bandgap reference circuit according to claim 2, characterized in that: The zero temperature coefficient first current mirror module includes a first positive temperature coefficient current mirror branch and a first negative temperature coefficient current mirror branch, the first end of the first positive temperature coefficient current mirror branch is connected to the first end of the positive temperature coefficient current generating module, the first end of the first negative temperature coefficient current mirror branch is connected to the second end of the negative temperature coefficient current generating module, and the second end of the first positive temperature coefficient current mirror branch is connected to the second end of the first negative temperature coefficient current mirror branch.

4. The bandgap reference circuit according to claim 3, characterized in that: The zero temperature coefficient first current mirror module further includes a zero temperature coefficient first reference branch and a zero temperature coefficient first mirror branch, and the zero temperature coefficient second current mirror module includes a zero temperature coefficient second reference branch and a zero temperature coefficient second mirror branch; Wherein, the first end of the zero temperature coefficient first reference branch is connected to the second end of the first positive temperature coefficient current mirror branch and the second end of the first negative temperature coefficient current mirror branch, and the first end of the zero temperature coefficient first mirror branch is connected to the second end of the zero temperature coefficient first reference branch; The first end of the zero temperature coefficient second reference branch is connected to the second end of the zero temperature coefficient first mirror branch, the first end of the zero temperature coefficient second mirror branch is connected to the second end of the zero temperature coefficient second reference branch, and the second end of the zero temperature coefficient second mirror branch is connected to the first input end of the current comparison module.

5. The bandgap reference circuit according to claim 4, characterized in that: The zero temperature coefficient second current mirror module includes at least one zero temperature coefficient second mirror branch, and the current comparison module includes at least one current comparison unit, and the current comparison unit corresponds one-to-one to the zero temperature coefficient second mirror branch, and the second end of the zero temperature coefficient second mirror branch is connected to the first input end of the corresponding current comparison unit.

6. The bandgap reference circuit according to claim 1, characterized in that: The negative temperature coefficient current generation module includes a second positive temperature coefficient current mirror branch, a third positive temperature coefficient current mirror branch, a subthreshold region field effect transistor module and a negative temperature coefficient current reference branch; Wherein, the first end of the second positive temperature coefficient current mirror branch is connected to the first end of the positive temperature coefficient current generating module, and the first end of the third positive temperature coefficient current mirror branch is connected to the first end of the positive temperature coefficient current generating module; The first end of the negative temperature coefficient current reference branch is connected to the second end of the third positive temperature coefficient current mirror branch; The first end of the subthreshold region field effect tube module is connected to the second end of the second positive temperature coefficient current mirror branch, the second end is connected to the second end of the third positive temperature coefficient current mirror branch, and the third end is connected to the second end of the negative temperature coefficient current reference branch; The first end of the negative temperature coefficient current reference branch is also connected to the first end of the zero temperature coefficient current generating module.

7. The bandgap reference circuit according to claim 6, characterized in that: In the case where the second input terminal of the current comparison module is connected to the third terminal of the negative temperature coefficient current generation module, the negative temperature coefficient current generation module further includes at least one second negative temperature coefficient current mirror branch, and the current comparison module includes at least one current comparison unit, and the current comparison unit corresponds to the second negative temperature coefficient current mirror branch one by one; The first end of the second negative temperature coefficient current mirror branch is connected to the first end of the negative temperature coefficient current reference branch, and the second end is connected to the second input end of the corresponding current comparison unit.

8. The bandgap reference circuit according to claim 6, characterized in that: The subthreshold region field effect tube module comprises a first subthreshold region field effect tube unit, a second subthreshold region field effect tube unit, a first triode unit and a first resistor unit, and the control end of the first subthreshold region field effect tube unit is connected to the control end of the second subthreshold region field effect tube unit; Wherein, the first end of the first subthreshold region field effect tube unit is connected to the second end of the second positive temperature coefficient current mirror branch, and the first end of the first subthreshold region field effect tube unit is also connected to the second end of the first subthreshold region field effect tube unit; The first end of the first triode unit is connected to the third end of the first subthreshold region field effect transistor unit, the second end is connected to the third end of the first triode unit, and the third end is grounded; The first end of the second subthreshold region field effect tube unit is connected to the second end of the third positive temperature coefficient current mirror branch, and the second end is connected to the second end of the first subthreshold region field effect tube unit; The first end of the first resistor unit is connected to the third end of the second subthreshold region field effect tube unit, the first end is also connected to the second end of the negative temperature coefficient current reference branch, and the second end is grounded.

9. The bandgap reference circuit according to claim 1, characterized in that: The positive temperature coefficient current generation module includes a positive temperature coefficient current reference branch, a fourth positive temperature coefficient current mirror branch and a fifth positive temperature coefficient current mirror branch; Wherein, the second end of the positive temperature coefficient current reference branch is connected to the first current input end of the bandgap reference voltage generation module; The first end of the fourth positive temperature coefficient current mirror branch is connected to the first end of the positive temperature coefficient current reference branch, and the second end is connected to the second current input end of the bandgap reference voltage generation module; The first end of the fifth positive temperature coefficient current mirror branch is connected to the first end of the positive temperature coefficient current reference branch, and the second end is connected to the third current input end of the bandgap reference voltage generation module.

10. The bandgap reference circuit according to claim 9, characterized in that: In the case where the second input terminal of the current comparison module is connected to the second terminal of the positive temperature coefficient current generation module, the positive temperature coefficient current generation module further includes at least one fourth positive temperature coefficient current mirror branch, and the current comparison module includes at least one current comparison unit, and the current comparison unit corresponds to the fourth positive temperature coefficient current mirror branch one by one; The first end of the fourth positive temperature coefficient current mirror branch is connected to the first end of the positive temperature coefficient current reference branch, and the second end is connected to the second input end of the corresponding current comparison unit.

11. The bandgap reference circuit according to claim 9, characterized in that: The bandgap reference voltage generation module includes an operational amplifier unit, a first positive temperature coefficient current generation branch, a second positive temperature coefficient current generation branch and a bandgap reference voltage generation branch; The bandgap reference voltage generating branch includes a second resistance unit and a variable resistance unit connected in series, the current input end of the bandgap reference voltage generating branch is connected to the second end of the third positive temperature coefficient current mirror branch, the current output end is connected to the second positive temperature coefficient current generating branch, and the control end of the variable resistance unit is connected to the output end of the current comparison module, wherein the bandgap reference voltage refers to the voltage at the third current input end of the bandgap reference voltage generating branch.

12. The bandgap reference circuit according to claim 11, characterized in that: The variable resistance unit includes at least one third resistance unit, the current comparison module includes at least one current comparison unit, and the current comparison unit corresponds to the third resistance unit one by one; The third resistance unit is connected in parallel with the switch unit, and the output end of the current comparison unit corresponding to the third resistance unit is connected to the control end of the switch unit.

13. The bandgap reference circuit according to claim 1, characterized in that: The second input end of the current comparison module is also provided with a selector module; The first input terminal of the selector module is connected to the second terminal of the positive temperature coefficient current generating module, the second input terminal is connected to the third terminal of the negative temperature coefficient current generating module, and the output terminal is connected to the second input terminal of the current comparison module.

14. A chip, characterized in that: Comprising the bandgap reference circuit as claimed in any one of claims 1 to 13.

15. An electronic device, characterized in that: Comprising the bandgap reference circuit as claimed in any one of claims 1 to 13.

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