Bandgap reference circuit, voltage source, chip and electronic device
By using a chopper module to adjust the connection relationship in the bandgap reference circuit, flicker noise was eliminated, solving the circuit area and cost problems caused by noise interference, and enabling miniaturized design and wide application.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHIPSEA TECH SHENZHEN CO LTD
- Filing Date
- 2025-05-09
- Publication Date
- 2026-06-16
Smart Images
Figure CN224366362U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electronic circuit technology, specifically to a bandgap reference circuit, voltage source, chip, and electronic device. Background Technology
[0002] A bandgap reference circuit is an analog integrated circuit module that generates a stable, low-temperature-coefficient reference voltage, and is a crucial component of analog and mixed-signal systems. From precision measuring instruments to everyday mobile devices, from complex communication systems to advanced automotive electronics, all kinds of electronic products rely on bandgap reference circuits to provide a stable and accurate reference voltage to ensure proper circuit operation and accurate signal processing.
[0003] However, bandgap reference circuits currently face many technical bottlenecks, among which noise interference is a key factor affecting their performance. In order to reduce the flicker noise caused by resistors in bandgap reference circuits, related technologies usually sacrifice area, which is not only costly but also not conducive to miniaturization design and limits application scenarios. Utility Model Content
[0004] In view of the above problems, this application provides a bandgap reference circuit, voltage source, chip and electronic device to solve the above technical problems.
[0005] In a first aspect, this application provides a bandgap reference circuit, the bandgap reference circuit comprising:
[0006] Current source module;
[0007] Temperature-sensitive module;
[0008] The feedback resistor module is connected to the output terminal of the current source module;
[0009] The operational amplifier module has its two input terminals connected to the two output terminals of the feedback resistor module, and its output terminal connected to the current source module.
[0010] The first chopper module is electrically connected to the two input terminals of the temperature-sensitive module and to the two common terminals of the operational amplifier module and the feedback resistor module. It is used to adjust the connection relationship between the two common terminals and the two input terminals of the temperature-sensitive module according to the chopper signal.
[0011] The second chopper module is electrically connected to the output of the operational amplifier module and is used to adjust the connection between the two input terminals of the operational amplifier module and the output terminal of the operational amplifier module according to the chopper signal.
[0012] In this bandgap reference circuit, the first chopper module is electrically connected to the two input terminals of the temperature-sensitive module and to the two common terminals of the operational amplifier module and the feedback resistor module. The connection relationship between the two input terminals and the two common terminals can be adjusted according to the chopper signal. In conjunction with the second chopper module, the input-output relationship of the operational amplifier module is adjusted to achieve signal inversion. This eliminates flicker noise in the signal throughout the entire signal cycle, improves the stability of the reference voltage, reduces the circuit area, lowers the cost, and expands the application scenarios.
[0013] Secondly, this application also provides a voltage source, including the bandgap reference circuit described above.
[0014] Thirdly, this application also provides a chip, including a chip body and a bandgap reference circuit or voltage source as described above disposed on the chip body.
[0015] Fourthly, this application also provides an electronic device, including a device body and a bandgap reference circuit, voltage source or chip disposed on the device body as described above.
[0016] The bandgap reference circuit provided in this application is electrically connected to the two input terminals of the temperature-sensitive module via a first chopper module, and connected to the two common terminals of the operational amplifier module and the feedback resistor module. The connection relationship between the two input terminals and the two common terminals can be adjusted according to the chopper signal. In conjunction with the second chopper module, the input-output relationship of the operational amplifier module can be adjusted to achieve signal inversion and eliminate flicker noise in the signal throughout the entire signal cycle. Compared with related technologies that eliminate flicker noise at the expense of area, this reduces the circuit area, lowers the cost, and expands the application scenarios. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.
[0018] Figure 1 This is a schematic diagram of a bandgap reference circuit in related technologies;
[0019] Figure 2 This is a schematic diagram of a bandgap reference circuit provided in an embodiment of this application;
[0020] Figure 3 This is a schematic diagram of a first chopper module provided in an embodiment of this application;
[0021] Figure 4This is a schematic diagram of a second chopper module provided in an embodiment of this application;
[0022] Figure 5 This is a schematic diagram of a feedback resistor module provided in an embodiment of this application;
[0023] Figure 6 This is a schematic diagram of a temperature-sensitive module provided in an embodiment of this application;
[0024] Figure 7 This is a schematic diagram of a bandgap reference circuit provided in an embodiment of this application;
[0025] Figure 8 This is a schematic diagram of a calibration module provided in an embodiment of this application;
[0026] Figure 9 This is a schematic diagram of a bandgap reference circuit provided in the embodiments of this application;
[0027] Figure 10 yes Figure 9 A schematic diagram of the connection relationship of the bandgap reference circuit in the image when the chopper signal is high level;
[0028] Figure 11 yes Figure 9 A schematic diagram of the connection relationship of the bandgap reference circuit when the chopper signal is low. Detailed Implementation
[0029] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.
[0030] To enable those skilled in the art to better understand the solutions of this application, 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 a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.
[0031] In the embodiments of this application, it should be noted that, in this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.
[0032] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.
[0033] In the description of the embodiments of this application, the words "example" or "for example" are used to indicate exemplification, illustration, or description. Any embodiment or design described as "example" or "for example" in the embodiments of this application is not to be construed as being more preferred or having more advantages than another embodiment or design. The use of the words "example" or "for example" is intended to present relative concepts in a clear manner.
[0034] Furthermore, in the embodiments of this application, "multiple" refers to two or more. Therefore, in the embodiments of this application, "multiple" can also be understood as "at least two". "At least one" can be understood as one or more, such as one, two, or more. For example, including at least one means including one, two, or more, and is not limited to which ones are included. For example, including at least one of A, B, and C, then it could include A, B, C, A and B, A and C, B and C, or A and B and C.
[0035] It should be noted that in the embodiments of this application, "connection" can be understood as electrical connection. The connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.
[0036] In the embodiments of this application, the first terminal / first end of each transistor is one of the source and the drain, and the second terminal / second end of each transistor is the other of the source and the drain. Since the source and drain of a transistor can be structurally symmetrical, they can be structurally indistinguishable. That is, the first terminal / first end and the second terminal / second end of the transistor in the embodiments of this application can be structurally indistinguishable. For example, when the transistor is a P-type transistor, the first terminal / first end is the source, and the second terminal / second end is the drain; for example, when the transistor is an N-type transistor, the first terminal / first end is the drain, and the second terminal / second end is the source.
[0037] In the circuit structure provided by the embodiments of this application, nodes such as the first node and the second node do not represent actual existing components, but rather represent the junction points of related couplings in the circuit diagram. In other words, these nodes are equivalent to the junction points of related couplings in the circuit diagram.
[0038] Before introducing the bandgap reference circuit, voltage source, chip, and electronic device of this application, we will first introduce the relevant background information of the embodiments of this application.
[0039] Currently, the noise in bandgap reference circuits is mainly the flicker noise of operational amplifiers and resistors. This flicker noise, also known as 1 / f noise, is caused by the slow, random fluctuations in emitted electrons due to local fluctuations in the device, and usually occurs at lower frequencies.
[0040] like Figure 1 As shown, a traditional bandgap reference circuit typically connects a chopping frequency of f to the input and output terminals of an operational amplifier. ch A chopper switch is used to process the flicker noise of the operational amplifier. And for resistor R... 1A and resistance R 1B This is usually achieved by using a resistor with a larger area to reduce the resistance R. 1A and resistance R 1B The resulting flicker noise will continue until it accounts for a relatively low percentage of the total noise.
[0041] However, this method of suppressing resistor flicker noise comes at the cost of circuit area, which is not only costly but also unfavorable for miniaturization design, limiting its application scenarios.
[0042] Based on this, embodiments of this application provide a bandgap reference circuit, a voltage source, a chip, and an electronic device, which will be described in detail below.
[0043] First, this application provides a bandgap reference circuit, please refer to... Figure 2 , Figure 2This is a schematic diagram of a bandgap reference circuit provided in an embodiment of this application. The bandgap reference circuit 100 may include a current source module 110, a feedback resistor module 120, a first chopper module 130, a temperature sensitive module 140, an operational amplifier module 150, and a second chopper module 160. The current source module 110 is connected to the two input terminals of the feedback resistor module 120. The two output terminals of the feedback resistor module 120 are correspondingly connected to the two input terminals of the operational amplifier module 150, forming two common terminals, namely the first node N1 and the second node N2. The output terminal of the operational amplifier module 150 is connected to the current source module 110. The first chopper module 130 is electrically connected to the two input terminals of the temperature sensitive module 140 and is also connected to the first node N1 and the second node N2. It is used to adjust the connection relationship between the first node N1 and the second node N2 and the two input terminals of the temperature sensitive module 140 according to the chopper signal. The second chopper module 160 is electrically connected to the output terminal of the operational amplifier module 150. It is used to adjust the connection relationship between the two input terminals and the output terminal of the operational amplifier module 150 according to the chopper signal.
[0044] In this embodiment, the current source module 110 may include any existing switching transistor, including but not limited to metal-oxide-semiconductor field-effect transistors (MOSFETs), bipolar junction transistors (BJTs), junction field-effect transistors (JFETs), etc. The specific type can be determined according to the actual application scenario and is not limited here. The output terminal of the current source module 110 is connected to the two input terminals of the feedback resistor module 120. The feedback resistor module 120, the operational amplifier module 150, and the current source module 110 together form a feedback loop.
[0045] The temperature-sensitive module 140 is connected to the feedback resistor module 120 and the operational amplifier module 150 respectively through the first chopper module 130, and can be used to generate a temperature-independent voltage value output to the operational amplifier module 150.
[0046] The first chopper module 130 adjusts the connection relationship between the first node N1 and the second node N2 and the two input terminals of the temperature-sensitive module 140 according to the received chopper signal. For example, when the chopper signal is high, the first node N1 is connected to the first temperature-sensitive input terminal a of the temperature-sensitive module 140, and the second node N2 is connected to the second temperature-sensitive input terminal b of the temperature-sensitive module 140; while when the chopper signal is low, the first node N1 is switched to be connected to the second temperature-sensitive input terminal b, and the second node N2 is switched to be connected to the first temperature-sensitive input terminal a.
[0047] The second chopper module 160 is electrically connected to the output of the operational amplifier module 150. Based on the received chopper signal, it adjusts the connection between the two input terminals and the output of the operational amplifier module 150. For example, when the chopper signal is high, the non-inverting input terminal of the operational amplifier module 150 is connected to the non-inverting output terminal, and the inverting input terminal is connected to the inverting output terminal, resulting in a positive output voltage. When the chopper signal is low, the non-inverting input terminal is switched to be connected to the inverting output terminal, and vice versa, resulting in a negative output voltage, thus inverting the signal. In this way, for the entire signal cycle, the positive and negative flicker noise can cancel each other out, thereby eliminating flicker noise caused by components in the circuit such as resistors and operational amplifiers.
[0048] The bandgap reference circuit 100 provided in this embodiment is electrically connected to the two input terminals of the temperature-sensitive module 140 via a first chopper module 130, and connected to the two common terminals of the operational amplifier module 150 and the feedback resistor module 120. The connection relationship between the two input terminals and the two common terminals can be adjusted according to the chopper signal. In conjunction with the second chopper module 160, the input-output relationship of the operational amplifier module 150 is adjusted to achieve signal inversion and eliminate flicker noise in the signal throughout the entire signal cycle. Compared with related technologies that eliminate flicker noise at the expense of area, this reduces the circuit area, lowers the cost, and expands the application scenarios.
[0049] Next, continue with Figure 2 The modules shown are described in detail, along with the specific implementation methods that may be used in practical applications.
[0050] like Figure 3As shown, in some embodiments of this application, the first chopper module 130 may include a first chopper switch 1301, the feedback resistor module 120 is configured with a first feedback output terminal c and a second feedback output terminal d, and the temperature sensitive module 140 is configured with a first temperature sensitive input terminal a and a second temperature sensitive input terminal b; the first chopper switch 1301 can be used to alternately connect the first feedback output terminal c with the first temperature sensitive input terminal a and the second temperature sensitive input terminal b according to the chopping signal, and the second feedback output terminal d is alternately connected with the second temperature sensitive input terminal b and the first temperature sensitive input terminal a.
[0051] In this embodiment, the first chopper switch 1301 can be implemented using any existing chopper, which can switch the connection relationship between the first feedback output terminal c, the second feedback output terminal d, the first temperature-sensitive input terminal a, and the second temperature-sensitive input terminal b according to the level change of the received chopper signal.
[0052] For example, when the chopping signal is high, the first chopper switch 1301 can respond to the high-level chopping signal by connecting the first feedback output terminal c to the first temperature-sensitive input terminal a and the second feedback output terminal d to the second temperature-sensitive input terminal b, as follows. Figure 3 The red trace in the diagram; when the chopping signal transitions to a low level, the first chopper switch 1301 can respond to the low-level chopping signal by connecting the first feedback output terminal c to the second temperature-sensitive input terminal b, and the second feedback output terminal d to the first temperature-sensitive input terminal a, as shown. Figure 3 The green traces in the diagram. This allows for the alteration of the signals at the non-inverting and inverting inputs of the operational amplifier module 150.
[0053] like Figure 4 As shown, in some embodiments of this application, the second chopper module 160 may include a second chopper switch 1601, and the operational amplifier module 150 is configured with a non-inverting input terminal, an inverting input terminal, a non-inverting output terminal, and an inverting output terminal. The non-inverting input terminal is connected to the first feedback output terminal c, and the inverting input terminal is connected to the second feedback output terminal d. The second chopper switch 1601 can be used to alternately connect the non-inverting input terminal to the non-inverting output terminal and the inverting output terminal, and alternately connect the inverting input terminal to the inverting output terminal and the non-inverting output terminal, according to the chopper signal.
[0054] In this embodiment of the application, the second chopper switch 1601 can also be implemented using any existing chopper, which can switch the connection relationship between the non-inverting input terminal, the inverting input terminal, the non-inverting output terminal and the inverting output terminal according to the level change of the received chopper signal.
[0055] For example, when the chopping signal is high, the second chopper switch 1601 can respond to the high-level chopping signal by connecting the non-inverting input terminal to the non-inverting output terminal and the inverting input terminal to the inverting output terminal, such as... Figure 4 The red trace in the diagram; when the chopper signal transitions to a low level, the second chopper switch 1601 can respond to the low-level chopper signal by connecting the non-inverting input terminal to the inverting output terminal and vice versa, as shown in the diagram. Figure 3 The green traces in the diagram. In this way, by adjusting the duty cycle of the chopper signal to 50%, the positive and negative flicker noise in the output signal can cancel each other out within one signal cycle of the chopper signal.
[0056] like Figure 5 As shown, in some embodiments of this application, the feedback resistor module 120 may include a first resistor unit 1201 and a second resistor unit 1202. The first end of the first resistor unit 1201 and the first end of the second resistor unit 1202 are respectively connected to the output terminal of the current source module 110. The second end of the first resistor unit 1201 is connected to the non-inverting input terminal of the operational amplifier module 150, and the second end of the second resistor unit 1202 is connected to the inverting input terminal of the operational amplifier module 150.
[0057] In this embodiment of the application, the first resistor unit 1201 and the second resistor unit 1202 can be implemented using one or more series resistors. The specific implementation can be determined according to the actual application scenario and is not limited here.
[0058] The first resistor unit 1201 is connected to the non-inverting input terminal of the operational amplifier module 150, thereby forming a positive feedback loop of the bandgap reference circuit 100 with the first resistor unit 1201, the operational amplifier module 150, and the current source module 110; the second resistor unit 1202 is connected to the inverting input terminal of the operational amplifier module 150, thereby forming a negative feedback loop of the bandgap reference circuit 100 with the second resistor unit 1202, the operational amplifier module 150, and the current source module 110.
[0059] like Figure 6 As shown, in some embodiments of this application, the temperature-sensitive module 140 may include a first transistor Q1, a second transistor Q2, and a third resistor unit 1401. The first terminal of the third resistor unit 1401 and the first terminal of the first transistor Q1 are connected to the first chopper module 130. The control terminal of the first transistor Q1, the second terminal of the first transistor Q1, the control terminal of the second transistor Q2, and the second terminal of the second transistor Q2 are connected to the ground terminal GND1401.
[0060] In this embodiment, the first transistor Q1 and the second transistor Q2 can be implemented using any existing switching transistor, including but not limited to transistors, MOSFETs, etc.; the third resistor unit 1401 can be implemented using one or more series resistors.
[0061] Understandably, the transistor pair consisting of the first transistor Q1 and the second transistor Q2 can be used to provide a voltage that is negatively correlated with temperature, and the third resistor unit 1401 can provide a voltage that is positively correlated with temperature because it carries a current that is positively correlated with temperature. By adjusting the parameters of the first transistor Q1, the second transistor Q2 and / or the third resistor unit 1401, the operational amplifier module 150 can generate an output voltage that is independent of temperature.
[0062] As an example, Figure 6 The first transistor Q1 and the second transistor Q2 are NPN transistors, and the first transistor Q1 and the second transistor Q2 are mirrored. By adjusting the ratio between the first transistor Q1 and the second transistor Q2 and the resistance value of each resistor unit, the output voltage can be made to remain unchanged with temperature, thereby improving the reliability of the output voltage.
[0063] like Figure 7 As shown, in some embodiments of this application, the bandgap reference circuit 100 may further include a calibration module 170, which may be connected between the current source module 110 and the feedback resistor module 120 to calibrate the reference voltage signal output by the current source module 110.
[0064] Please see Figure 8 The calibration module 170 may include a variable resistor unit 1701, the first end of which is connected to the output of the current source module 110, and the second end of which is connected to the input of the feedback resistor module 120.
[0065] In this embodiment, the variable resistor unit 1701 can be implemented using any existing adjustable resistor, including but not limited to a Trimming DAC (trimming digital-to-analog converter), a digital potentiometer, etc.; the reference voltage signal is calibrated by adjusting the resistance value of the variable resistor unit 1701.
[0066] like Figure 9 As shown, as an example, the current source module 110 includes a PMOS transistor M1, the variable resistor unit 1701 includes an adjustable resistor RT, the first resistor unit 1201 includes an eleventh resistor R11, the second resistor unit 1202 includes a twelfth resistor R12, the first chopper switch 1301 is chop1, the second chopper switch 1601 is chop2, the third resistor unit 1401 includes a fourteenth resistor R14, and the operational amplifier module 150 includes an operational amplifier U1. The connection relationship of each device is as described in the above embodiment and as follows: Figure 9 As can be seen, this will not be elaborated upon here.
[0067] The following is combined Figure 9The working principle of the bandgap reference circuit provided in the embodiments of this application will be described in detail.
[0068] Let the chopping signal be the clock signal CLK_chop. Set the high level potential of the clock signal CLK_chop as the first phase and the low level potential of the clock signal CLK_chop as the second phase P2.
[0069] The circuit connection relationship in the first phase is as follows: Figure 10 As shown, assuming the gain of op-amp U1 is Av, the flicker noise of the eleventh resistor R11 and the twelfth resistor R12 is equivalent to Vnoise_res at the lower end of the eleventh resistor R11, and the input noise of op-amp U1 is equivalent to Vos_op at the non-inverting input terminal, then in the first phase case, the noise at the output terminal of op-amp U1 is Av(Vnoise_res+Vos_op).
[0070] In the second phase case, the entire circuit connection is as follows: Figure 11 As shown, in the second phase case, the noise at the output of op-amp U1 is -Av(Vnoise_res+Vos_op).
[0071] Since flicker noise is low-frequency noise, the frequency of (Vnoise_res + Vos_op) is very low compared to the clock signal CLK_chop. Therefore, the noise magnitude in the first and second phases is approximately equal and the direction is opposite. After long-term observation, the noise output of op-amp U1 is approximately 0. In other words, using the chopping method in the bandgap reference circuit of this application, the low-frequency noise of op-amp U1 can be eliminated, and the flicker noise of the resistor can also be eliminated without sacrificing area, making it more suitable for the miniaturization design pursued in current electronic design.
[0072] Based on the above embodiments, this application also provides a voltage source, which includes the above-described bandgap reference circuit.
[0073] Because this voltage source incorporates the bandgap reference circuit of the above embodiments, it possesses all the beneficial effects of the bandgap reference circuit in any of the above embodiments, which will not be elaborated here.
[0074] Based on the above embodiments, this application also provides a chip, which includes a chip body and a bandgap reference circuit or voltage source disposed on the chip body as described above.
[0075] The chip can be, but is not limited to, a system-on-chip (SOC) or a system-in-package (SIP) chip. It can be used in applications such as communications, audio amplifiers, power supply equipment, and automobiles. No specific limitations are specified here.
[0076] Because the chip is equipped with the bandgap reference circuit of the above embodiments, it has all the beneficial effects of the bandgap reference circuit in any of the above embodiments, which will not be repeated here.
[0077] Based on the above embodiments, this application also provides an electronic device, which includes a device body and a bandgap reference circuit, voltage source or chip disposed on the device body as described above.
[0078] The electronic device can be a communication device, an audio amplifier, a power supply device, a control device in a car, a display device, etc. Because the electronic device is equipped with the bandgap reference circuit of the above embodiments, it has all the beneficial effects of the bandgap reference circuit in any of the above embodiments, which will not be repeated here.
[0079] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Although this application has disclosed preferred embodiments as above, it is not intended to limit this application. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the technical solution of this application. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.
Claims
1. A bandgap reference circuit, characterized in that, include: Current source module; Temperature-sensitive module; A feedback resistor module is connected to the output terminal of the current source module; An operational amplifier module, wherein the two input terminals of the operational amplifier module are connected to the two output terminals of the feedback resistor module respectively, and the output terminal of the operational amplifier module is connected to the current source module; The first chopper module is electrically connected to the two input terminals of the temperature-sensitive module and to the two common terminals of the operational amplifier module and the feedback resistor module. It is used to adjust the connection relationship between the two common terminals and the two input terminals of the temperature-sensitive module according to the chopper signal. The second chopper module is electrically connected to the output terminal of the operational amplifier module and is used to adjust the connection relationship between the two input terminals of the operational amplifier module and the output terminal of the operational amplifier module according to the chopper signal.
2. The bandgap reference circuit according to claim 1, characterized in that, The first chopper module includes a first chopper switch, the feedback resistor module is configured with a first feedback output terminal and a second feedback output terminal, and the temperature sensitive module is configured with a first temperature sensitive input terminal and a second temperature sensitive input terminal. The first chopper switch is used to alternately connect the first feedback output terminal to the first temperature-sensitive input terminal and the second temperature-sensitive input terminal according to the chopper signal, and to alternately connect the second feedback output terminal to the second temperature-sensitive input terminal and the first temperature-sensitive input terminal.
3. The bandgap reference circuit according to claim 2, characterized in that, The second chopper module includes a second chopper switch, and the operational amplifier module is configured with a non-inverting input terminal, an inverting input terminal, a non-inverting output terminal, and an inverting output terminal. The non-inverting input terminal is connected to the first feedback output terminal, and the inverting input terminal is connected to the second feedback output terminal. The second chopper switch is used to alternately connect the non-inverting input terminal to the non-inverting output terminal and the inverting output terminal according to the chopper signal, and to alternately connect the inverting input terminal to the inverting output terminal and the non-inverting output terminal.
4. The bandgap reference circuit according to any one of claims 1-3, characterized in that, The feedback resistor module includes a first resistor unit and a second resistor unit. The first end of the first resistor unit and the first end of the second resistor unit are respectively connected to the output terminal of the current source module. The second end of the first resistor unit is connected to the non-inverting input terminal of the operational amplifier module, and the second end of the second resistor unit is connected to the inverting input terminal of the operational amplifier module.
5. The bandgap reference circuit according to any one of claims 1-3, characterized in that, The temperature-sensitive module includes a first transistor, a second transistor, and a third resistor unit. The first end of the third resistor unit and the first end of the first transistor are respectively connected to the first chopper module. The second end of the third resistor unit is connected to the first end of the second transistor. The control terminal of the first transistor, the second end of the first transistor, the control terminal of the second transistor, and the second end of the second transistor are connected to the ground terminal.
6. The bandgap reference circuit according to any one of claims 1-3, characterized in that, The bandgap reference circuit also includes a calibration module, which is connected between the current source module and the feedback resistor module to calibrate the reference voltage signal output by the current source module.
7. The bandgap reference circuit according to claim 6, characterized in that, The calibration module includes a variable resistor unit, the first end of which is connected to the output terminal of the current source module, and the second end of which is connected to the input terminal of the feedback resistor module.
8. A voltage source, characterized in that, Includes the bandgap reference circuit as described in any one of claims 1-7.
9. A chip, characterized in that, It includes a chip body and a bandgap reference circuit as described in any one of claims 1-7 or a voltage source as described in claim 8, disposed on the chip body.
10. An electronic device, characterized in that, It includes a device body and a bandgap reference circuit as described in any one of claims 1-7, a voltage source as described in claim 8, or a chip as described in claim 9, disposed on the device body.