Band-gap reference circuit with full-temperature-range self-adaptive adjustment function

Abstract

The invention discloses a full-temperature-range self-adaptive adjustment band-gap reference circuit, and relates to the field of integrated circuits, the full-temperature-range self-adaptive adjustment band-gap reference circuit comprises a temperature detection module, a control module and a band-gap reference core circuit, and the control module is connected with the temperature detection module and the band-gap reference core circuit; the circuit working process comprises the steps that the environment temperature of the band-gap reference circuit is detected; a corresponding voltage signal is output to the control module according to the environment temperature; converting the received voltage signal into a control signal; the control signal is output to the band-gap reference core circuit; according to the received control signal, band-gap reference voltage meeting the environment temperature requirement is output. By introducing the temperature detection and control module, the relation between the temperature and the output reference voltage can be established, and the purpose of adaptive adjustment is achieved, so that the resistance module in the band-gap reference can be adaptively trimmed at each temperature section, and the high-precision band-gap reference voltage within the full temperature range is obtained.

Description

Technical Field

[0001] The invention relates to the field of integrated circuits, and in particular to a bandgap reference circuit capable of adaptively adjusting the entire temperature range. Background Art

[0002] In various circuits with high-precision requirements, such as high-precision voltage comparators, high-precision digital-to-analog and address conversion modules, high-precision phase-locked loop circuits, and high-precision power management circuits, the bandgap reference is used as the core circuit to provide a DC voltage reference that is almost unaffected by the power supply voltage and has a determined relationship with temperature. Its performance is directly related to the stability and output accuracy of the entire circuit.

[0003] Currently, consumer-grade, industrial-grade, and automotive-grade chip products all have certain requirements for the operating temperature range. For example, automotive-grade chips usually require that they work normally at -40°C to 125°C. In traditional bandgap reference circuits, the positive temperature coefficient voltage can offset the linear part of the negative temperature coefficient voltage by weighting, and output a bandgap reference voltage with a zero temperature coefficient at a certain temperature point, and is almost unaffected by the power supply voltage, but the nonlinear part of the negative temperature coefficient voltage is not taken into account. Due to the influence of the nonlinear part, even if the circuit parameters are very well matched, the output bandgap reference voltage V REF , the accuracy is still low over the entire temperature range and no longer meets the design requirements of high-precision and high-stability chips. Summary of the invention

[0004] The present invention provides a bandgap reference circuit capable of adaptive adjustment within a full temperature range, so as to overcome at least one technical problem existing in the prior art.

[0005] The present invention provides a bandgap reference circuit with full temperature range adaptive adjustment, comprising a temperature detection module, a control module and a bandgap reference core circuit, wherein the control module is respectively connected to the temperature detection module and the bandgap reference core circuit; the circuit workflow comprises:

[0006] Detecting the ambient temperature of the bandgap reference circuit;

[0007] According to the ambient temperature, output a corresponding voltage signal to the control module;

[0008] Converting the received voltage signal into a control signal;

[0009] outputting the control signal to the bandgap reference core circuit;

[0010] A bandgap reference voltage that meets the accuracy requirement at the current ambient temperature is output according to the control signal.

[0011] Optionally, the control module includes an address conversion module and a memory;

[0012] The memory includes N storage units, and the storage units are used to store control signals;

[0013] The address conversion module is used to convert the voltage signal, output an address signal corresponding to the ambient temperature, and address the corresponding storage unit according to the address signal to read the control signal.

[0014] Optionally, the bandgap reference core circuit includes: transistor PNP1, transistor PNP2, transistor PNP3, operational amplifier OPA, N-type field effect transistor NM1, N-type field effect transistor NM2, N-type field effect transistor NM3, resistor R0, resistor module R1; wherein:

[0015] The reverse input terminal of the operational amplifier OPA is connected to the emitter of the transistor PNP1 and the drain of the N-type field effect transistor NM1, the non-inverting input terminal of the operational amplifier OPA is connected to one end of the resistor R0 and the drain of the N-type field effect transistor NM2, and the output terminal of the operational amplifier OPA is connected to the gate of the N-type field effect transistor NM1; the gate of the N-type field effect transistor NM1, the gate of the N-type field effect transistor NM2 and the gate of the N-type field effect transistor NM3 are connected to form a current mirror network; the N The source of the N-type field effect transistor NM1, the source of the N-type field effect transistor NM2 and the source of the N-type field effect transistor NM3 are connected to the power supply VDD; the collector and the base of the transistor PNP1 are grounded, the collector and the base of the transistor PNP2 are grounded, and the collector and the base of the transistor PNP3 are grounded; the other end of the resistor R0 is connected to the emitter of the transistor PNP2; one end of the resistor module R1 is connected to the emitter of the transistor PNP3, and the other end is connected to the drain of the N-type field effect transistor NM3 and serves as the output end of the bandgap reference voltage.

[0016] Optionally, after the operational amplifier OPA feedback is stabilized, the voltages at the non-inverting input terminal and the reverse input terminal are equal and equal to the negative temperature coefficient voltage V BE1 , the ratio of the number of transistors PNP1 to PNP2 is M, and a voltage drop ΔV is generated on the resistor R0 BE It is expressed as:

[0017]

[0018] Among them, V BE1 Represents the base-emitter voltage of transistor PNP1, V BE2 Represents the base-emitter voltage of transistor PNP2, V TRepresents thermal voltage.

[0019] Optionally, the voltage drop ΔV BE A positive temperature coefficient circuit is generated on R0 and is mirrored to the resistor module R1 through a current mirror network to form a positive temperature coefficient voltage. The output bandgap reference voltage V REF It is expressed as:

[0020]

[0021] Among them, V BE3 Represents the base-emitter voltage of transistor PNP3.

[0022] Optionally, the control signal is output to the bandgap reference core circuit, specifically:

[0023] Outputting the control signal to the resistance module R1 of the bandgap reference core circuit;

[0024] The resistor module R1 is trimmed and adjusted according to the control signal to change its resistance value, and a bandgap reference voltage that meets the accuracy requirement in the corresponding temperature range is output.

[0025] Optionally, the control signal writing process of the memory includes:

[0026] Create a lookup table;

[0027] According to the lookup table, filter the data to obtain control data;

[0028] The control data is written.

[0029] Optionally, establishing the lookup table includes obtaining the intersection of control signals corresponding to the plurality of chips in N temperature ranges, specifically:

[0030] The full temperature range required by the circuit is divided into T1~T N N temperature segments;

[0031] Take multiple chips, adjust the ambient temperature to each temperature range for each chip, write data to the memory in each temperature range, and record the corresponding output bandgap reference voltage V REF ; Set the voltage value to Bandgap reference voltage V REF The corresponding data set is used as the control signal set of the current chip in the current temperature range;

[0032] Take the intersection of the control signal sets of all the chips under test in the corresponding temperature range;

[0033] The lookup table is constructed using the intersection of all temperature section control signal sets.

[0034] Optionally, data is filtered according to the lookup table, specifically:

[0035] A lookup table is used to select one universal control signal from the intersection of each temperature segment control signal set to form the control data to be written.

[0036] Optionally, the control data is written, specifically:

[0037] The control data is written into the memory.

[0038] The innovative features of the embodiments of the present invention include:

[0039] 1. In this embodiment, by introducing a temperature detection and control module, a connection between temperature and output reference voltage can be established to achieve the purpose of adaptive adjustment, thereby being able to adaptively adjust the resistance module inside the bandgap reference in each temperature range to obtain a high-precision bandgap reference voltage over the entire temperature range, which is one of the innovative features of the embodiment of the present invention.

[0040] 2. In this embodiment, the implementation of a high-precision bandgap reference voltage enables the circuit to have a wider range of applications and can be applied to core circuits of more demanding chip designs, which is one of the innovations of the embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 A schematic diagram of a circuit structure provided by an embodiment of the present invention;

[0043] Figure 2 A circuit working flow diagram provided for an embodiment of the present invention;

[0044] Figure 3 A schematic diagram of the control module structure provided by an embodiment of the present invention;

[0045] Figure 4 A schematic diagram of a bandgap reference core circuit provided by an embodiment of the present invention;

[0046] Figure 5 A schematic diagram of the temperature characteristics of the output bandgap reference voltage provided by an embodiment of the present invention;

[0047] Figure 6 A flow chart of memory control signal writing provided by an embodiment of the present invention;

[0048] Figure 7 A flow chart of establishing a lookup table provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] It should be noted that the terms "including" and "having" and any variations thereof in the embodiments of the present invention and the accompanying drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0051] The embodiment of the present invention discloses a bandgap reference circuit with full temperature range adaptive adjustment, which is described in detail below.

[0052] Figure 1 A schematic diagram of a circuit structure provided by an embodiment of the present invention, Figure 2 For the circuit working flow diagram provided by the embodiment of the present invention, please refer to Figure 1 and Figure 2 The bandgap reference circuit with full temperature range adaptive adjustment provided by the embodiment of the present invention includes: a temperature detection module, a control module and a bandgap reference core circuit, wherein the control module is connected to the temperature detection module and the bandgap reference core circuit respectively; the working process of the circuit includes:

[0053] Step 1: Detect the ambient temperature of the bandgap reference circuit;

[0054] Step 2: According to the ambient temperature, output the corresponding voltage signal to the control module;

[0055] Step 3: Convert the received voltage signal into a control signal;

[0056] Step 4: Output the control signal to the bandgap reference core circuit;

[0057] Step 5: Output a bandgap reference voltage that meets the accuracy requirement at the current ambient temperature according to the control signal.

[0058] Specifically, the traditional bandgap reference circuit does not take into account the influence of the nonlinear part of the negative temperature coefficient voltage. Even if the circuit parameters are well matched, the output bandgap reference voltage V REF , the accuracy is still low in the full temperature range. Therefore, based on the traditional bandgap reference circuit, the present invention introduces a temperature detection and control module to adaptively adjust the resistance module inside the bandgap reference to obtain a high-precision bandgap reference voltage in the full temperature range. Based on this, the embodiment of the present invention proposes a bandgap reference circuit with full temperature range adaptive adjustment, please refer to Figure 1 ,The circuit includes a temperature detection module, a control module and a bandgap reference core circuit.

[0059] In the bandgap reference circuit provided in the present invention, the control module is connected to the temperature detection module and the bandgap reference core circuit respectively to form the entire chip structure. When the circuit works in different temperature ranges, the bandgap reference voltage will have deviations and fail to meet the accuracy requirements. In order to be able to output a bandgap reference voltage that meets the accuracy requirements in the entire temperature range, the present invention introduces a temperature detection module and a control module. Please refer to Figure 2 In the present invention, first, in step 1, a temperature detection module is used to detect the current ambient temperature of the circuit. After obtaining the current ambient temperature, in step 2, a voltage signal V corresponding to the current ambient temperature is generated. Det , and the voltage signal V Det Output to the control module.

[0060] The control module receives the voltage signal V Det Then, in step 3, the received voltage signal V Det The control module includes an address conversion module and a memory, in which the control signal is stored. Here, the voltage signal V Det Converting the voltage signal V into a control signal Det Convert it into an address signal, and then use the address signal to address the memory to obtain the corresponding control signal.

[0061] After the control signal is obtained, the control signal is output to the bandgap reference core circuit through step 4. After the bandgap reference core circuit receives the control signal, in step 5, the resistance value of the internal resistor of the bandgap reference core circuit is changed according to the received control signal, thereby outputting a bandgap reference voltage that meets the current ambient temperature requirements.

[0062] The bandgap reference circuit with full temperature range adaptive adjustment provided by the embodiment of the present invention, based on the traditional bandgap reference circuit, can establish a connection between temperature and output reference voltage by introducing a temperature detection and control module, so as to achieve the purpose of adaptive adjustment, thereby being able to adaptively adjust the resistance module inside the bandgap reference in each temperature range, and obtain a high-precision bandgap reference voltage in the full temperature range, so that the circuit has a larger scope of application and can be applied to the core circuits of more high-demand chip designs.

[0063] Optionally, Figure 3 For a schematic diagram of the control module structure provided by an embodiment of the present invention, please refer to Figure 3 The control module includes an address conversion module and a memory; the memory includes N storage units, and the storage unit is used to store the control signal; the address conversion module is used to convert the voltage signal, output the address signal corresponding to the ambient temperature, and address the corresponding storage unit according to the address signal to read the control signal.

[0064] Specifically, please refer to Figure 3 The control module includes an address conversion module and a non-volatile memory, which can write control signals to the bandgap reference circuit to achieve adjustment. The working process of the control module can be regarded as the process of reading memory data and then outputting control signals. Assume that the full temperature range required by the chip (for example, the automotive-grade chip is required to work at -40℃~125℃) is divided into N temperature segments T1, T2…T N .

[0065] The address conversion module converts the input voltage signal V det Match the corresponding temperature segment and output the address signal of the corresponding temperature segment.

[0066] The corresponding memory also has N storage units storing the data of the control signal. After the address conversion module outputs the address signal, the circuit performs addressing according to the address signal, reads the data of the corresponding storage unit of the memory, outputs the control signal, and gives it to the bandgap reference core circuit.

[0067] Optionally, Figure 4 For the schematic diagram of the bandgap reference core circuit provided by the embodiment of the present invention, please refer to Figure 4, a bandgap reference core circuit, including: a transistor PNP1, a transistor PNP2, a transistor PNP3, an operational amplifier OPA, an N-type field effect transistor NM1, an N-type field effect transistor NM2, an N-type field effect transistor NM3, a resistor R0, and a resistor module R1; wherein, the reverse input end of the operational amplifier OPA is connected to the emitter of the transistor PNP1 and the drain of the N-type field effect transistor NM1, the same-direction input end of the operational amplifier OPA is connected to one end of the resistor R0 and the drain of the N-type field effect transistor NM2, and the output end of the operational amplifier OPA is connected to the gate of the N-type field effect transistor NM1; the gate of the N-type field effect transistor NM1 The gates of the N-type field effect transistors NM2 and N-type field effect transistors NM3 are connected to form a current mirror network; the source of the N-type field effect transistors NM1, N-type field effect transistors NM2 and N-type field effect transistors NM3 are connected to the power supply VDD; the collector and base of the transistor PNP1 are grounded, the collector and base of the transistor PNP2 are grounded, and the collector and base of the transistor PNP3 are grounded; the other end of the resistor R0 is connected to the emitter of the transistor PNP2; one end of the resistor module R1 is connected to the emitter of the transistor PNP3, and the other end is connected to the drain of the N-type field effect transistor NM3 and serves as the output end of the bandgap reference voltage.

[0068] Specifically, please refer to Figure 4 The bandgap reference core circuit is designed with a resistor module R1 inside, and the resistance value is changed by the control signal. Figure 4 It is a commonly used bandgap reference circuit for generating a reference voltage VREF, including transistors PNP1, PNP2, and PNP3, an operational amplifier OPA, and N-type field effect transistors NM1, N-type field effect transistors NM2, and N-type field effect transistors NM3, a resistor R0, and a resistor module R1.

[0069] The emitter of transistor PNP1 is connected to the inverting input terminal A of operational amplifier OPA and is grounded through the gate and base; one end of resistor R0 is connected to the non-inverting input terminal B of operational amplifier OPA, and the other end is connected to the emitter of transistor PNP2 and is grounded through its collector and base; the drains of N-type field effect transistors NM1 and N-type field effect transistors NM2 are connected to the input terminal of operational amplifier OPA, the gates are connected to the output terminal of operational amplifier OPA and are connected to the gate of N-type field effect transistor NM3 to form a current mirror network; one end of resistor module R1 is connected to the emitter of transistor PNP3 and is grounded through its collector and base, and the other end is connected to the drain of N-type field effect transistor NM3 and serves as the output terminal of bandgap reference voltage.

[0070] After the operational amplifier OPA feedback is stable, the voltages at points A and B are clamped to be equal and equal to the negative temperature coefficient voltage VBE1 , the ratio of the number of transistors PNP1 to PNP2 is M, then a voltage drop ΔV is generated on the resistor R0 BE It is expressed as:

[0071]

[0072] Among them, V BE1 Represents the base-emitter voltage of transistor PNP1, V BE2 Represents the base-emitter voltage of transistor PNP2, V T Here, the ratio of the number of transistors PNP1 to that of transistors PNP2 can usually be 8.

[0073] Voltage drop ΔV BE A positive temperature coefficient circuit is generated on R0 and is mirrored to the resistor module R1 through the current mirror network to form a voltage with a positive temperature coefficient. At this time, the output bandgap reference voltage V REF It can be expressed as:

[0074]

[0075] Among them, V BE3 Represents the base-emitter voltage of transistor PNP3.

[0076] Optionally, the control signal is output to the bandgap reference core circuit, specifically: outputting the control signal to the resistance module R1 of the bandgap reference core circuit; adjusting the resistance module R1 according to the control signal to change its resistance value, and outputting a bandgap reference voltage that meets the accuracy requirements in the corresponding temperature range.

[0077] Specifically, in theory, under sub-micron technology, the reference voltage V REF =1.20V, but due to the influence of temperature and manufacturing process deviation, the output reference voltage will deviate at temperatures outside the temperature range where the zero temperature coefficient is located, and needs to be adjusted. The bandgap reference core circuit is designed with a resistor module R1. This embodiment outputs a control signal to the resistor module R1 of the bandgap reference core circuit, uses the control signal to adjust the resistor module R1, changes its resistance value, and outputs a bandgap reference voltage that meets the accuracy requirements in the corresponding temperature range, thereby obtaining a bandgap reference voltage that meets the accuracy requirements in each temperature range.

[0078] Nowadays, many high-precision chips have certain requirements for the output voltage accuracy of the bandgap reference. REF Precision can be defined as:

[0079]

[0080] Among them, V REF_relDefined as the measured voltage of the chip, V REF_nom is the ideal value of the required bandgap reference voltage. Under sub-micron technology, V REF_nom The technical solution proposed by the present invention outputs a bandgap reference voltage V REF The accuracy range is Within the full temperature range of -40℃~125℃, after the entire working process, the output reference voltage V REF Reference value Figure 5 , Figure 5 A schematic diagram of the temperature characteristics of the output bandgap reference voltage provided by an embodiment of the present invention.

[0081] Optionally, Figure 6 For a flowchart of memory control signal writing provided by an embodiment of the present invention, please refer to Figure 6 , the control signal writing process of the memory includes:

[0082] Step 10: Create a lookup table;

[0083] Step 11: Filter the data according to the lookup table to obtain the control data;

[0084] Step 12: Write control data.

[0085] Specifically, please refer to Figure 3 and Figure 6 , a non-volatile memory is added to the control module of the present invention, and control signals can be written to the memory during the chip testing phase. When writing the control signal, first in step 10, a lookup table is established by performing sample test statistics on multiple chips. Then in step 11, data in each temperature range is screened out according to the lookup table, that is, from the intersection of the control signal sets of each temperature segment, one universal control signal is selected to form the control data to be written. After obtaining the control data, step 12 is used to write the control data into the memory, and the control signal writing is completed.

[0086] Optionally, Figure 7 For a flowchart of establishing a lookup table provided in an embodiment of the present invention, please refer to 6 and Figure 7 In step 10, establishing a lookup table includes obtaining the intersection of control signals corresponding to multiple chips in N temperature segments, specifically: step 101, dividing the full temperature range required by the circuit from low to high into T1~T N N temperature segments; Step 102, taking multiple chips, adjusting the ambient temperature to each temperature segment for each chip, writing data to the memory in turn in each temperature segment, and recording the corresponding output bandgap reference voltage V REF ; Set the voltage value to Bandgap reference voltage VREF The corresponding data set is used as the control signal set of the current chip in the current temperature range; step 103, taking the intersection of the control signal sets of all the tested chips in the corresponding temperature range; step 104, using the intersection of all temperature range control signal sets to form a lookup table.

[0087] Specifically, please refer to Figure 7 During the chip testing phase, data can be written to the memory of the control module. When writing data, firstly, through step 101, the full temperature range required by the circuit is divided into T1~T2 from low to high. N Then, through step 102, take a single chip, first adjust the ambient temperature to the T1 range, take the control signal as 8 bits as an example, write data 00000000 to 11111111 to the memory in sequence, and record the corresponding output bandgap reference voltage V REF , for voltage values ​​in The set of control signals corresponding to the bandgap reference voltage within the range is statistically formed as the control signal set that meets the requirements of the current chip in the T1 temperature segment.

[0088] Adjust the ambient temperature to the T2 range, and use the same method to obtain the control signal set that meets the requirements of the current chip in the T2 temperature range. Similarly, the control signal set that meets the requirements of the current chip in the T1~T N The N temperature segments each meet the required control signal set.

[0089] In order to improve the accuracy of the sample, this embodiment tests and counts multiple chips. For each chip, the same method as above is used to obtain the control signal sets of all chips in each temperature range. In the same temperature range, there are intersections between the control signal sets of different chips. Through step 103, the intersection of the control signal sets between different chips in each temperature range is taken out as the intersection of the control signal sets of the corresponding temperature range. Through step 104, the intersection of the control signal sets of all temperature ranges is used to form a lookup table, which lists the control signal sets of T1~T N There are N temperature segments, and the intersection of the control signal sets corresponding to each temperature segment is taken out.

[0090] It should be noted that the control signal is 8 bits, which is only an implementation in this embodiment and is not intended to limit the present invention. The circuit provided by the present invention is universal and applicable to circuits with control signals of any word length. This embodiment establishes a lookup table through a large number of test samples, from which universal data can be found.

[0091] Those skilled in the art can understand that the accompanying drawings are only schematic diagrams of an embodiment, and the modules or processes in the accompanying drawings are not necessarily required to implement the present invention.

[0092] Those skilled in the art can understand that the modules in the device in the embodiment can be distributed in the device in the embodiment according to the description of the embodiment, or can be changed accordingly and located in one or more devices different from the embodiment. The modules in the above embodiment can be combined into one module, or can be further divided into multiple sub-modules.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A bandgap reference circuit with full temperature range adaptive adjustment, comprising a temperature detection module, a control module and a bandgap reference core circuit, wherein the control module is connected to the temperature detection module and the bandgap reference core circuit respectively; characterized in that: The circuit workflow includes: Detecting the ambient temperature of the bandgap reference circuit; According to the ambient temperature, output a corresponding voltage signal to the control module; Converting the received voltage signal into a control signal; outputting the control signal to the bandgap reference core circuit; A bandgap reference voltage that meets the accuracy requirement at the current ambient temperature is output according to the control signal.

2. The bandgap reference circuit with full temperature range adaptive adjustment according to claim 1, characterized in that: The control module includes an address conversion module and a memory; The memory includes N storage units, and the storage units are used to store control signals; The address conversion module is used to convert the voltage signal, output an address signal corresponding to the ambient temperature, and address the corresponding storage unit according to the address signal to read the control signal.

3. The bandgap reference circuit with full temperature range adaptive adjustment according to claim 1, characterized in that: The bandgap reference core circuit includes: transistors PNP1, PNP2, PNP3, operational amplifier OPA, N-type field effect transistors NM1, N-type field effect transistors NM2, N-type field effect transistors NM3, resistor R0, and resistor module R1; wherein: The reverse input terminal of the operational amplifier OPA is connected to the emitter of the transistor PNP1 and the drain of the N-type field effect transistor NM1, the non-inverting input terminal of the operational amplifier OPA is connected to one end of the resistor R0 and the drain of the N-type field effect transistor NM2, and the output terminal of the operational amplifier OPA is connected to the gate of the N-type field effect transistor NM1; the gate of the N-type field effect transistor NM1, the gate of the N-type field effect transistor NM2 and the gate of the N-type field effect transistor NM3 are connected to form a current mirror network; the N The source of the N-type field effect transistor NM1, the source of the N-type field effect transistor NM2 and the source of the N-type field effect transistor NM3 are connected to the power supply VDD; the collector and the base of the transistor PNP1 are grounded, the collector and the base of the transistor PNP2 are grounded, and the collector and the base of the transistor PNP3 are grounded; the other end of the resistor R0 is connected to the emitter of the transistor PNP2; one end of the resistor module R1 is connected to the emitter of the transistor PNP3, and the other end is connected to the drain of the N-type field effect transistor NM3 and serves as the output end of the bandgap reference voltage.

4. The bandgap reference circuit with full temperature range adaptive adjustment according to claim 3, characterized in that: After the operational amplifier OPA feedback is stable, the voltages at the same-direction input and the reverse input are equal and equal to the negative temperature coefficient voltage V BE1 , the ratio of the number of transistors PNP1 to PNP2 is M, and a voltage drop ΔV is generated on the resistor R0 BE It is expressed as: Among them, V BE1 Represents the base-emitter voltage of transistor PNP1, V BE2 Represents the base-emitter voltage of transistor PNP2, V T Represents thermal voltage.

5. The bandgap reference circuit with full temperature range adaptive adjustment according to claim 4, characterized in that: Voltage drop ΔV BE A positive temperature coefficient circuit is generated on R0 and is mirrored to the resistor module R1 through a current mirror network to form a positive temperature coefficient voltage. The output bandgap reference voltage V REF It is expressed as: Among them, V BE3 Represents the base-emitter voltage of transistor PNP3.

6. The bandgap reference circuit with full temperature range adaptive adjustment according to claim 3, characterized in that: Outputting the control signal to the bandgap reference core circuit is specifically: Outputting the control signal to the resistance module R1 of the bandgap reference core circuit; The resistor module R1 is trimmed and adjusted according to the control signal to change its resistance value, and a bandgap reference voltage that meets the accuracy requirement in the corresponding temperature range is output.

7. The bandgap reference circuit with full temperature range adaptive adjustment according to claim 2, characterized in that: The control signal writing process of the memory includes: Create a lookup table; According to the lookup table, filter the data to obtain control data; The control data is written.

8. The bandgap reference circuit with full temperature range adaptive adjustment according to claim 7, characterized in that: Establishing the lookup table includes obtaining the intersection of the control signals corresponding to multiple chips in N temperature ranges, specifically: The full temperature range required by the circuit is divided into T1~T N N temperature segments; Take multiple chips, adjust the ambient temperature to each temperature range for each chip, write data to the memory in each temperature range, and record the corresponding output bandgap reference voltage V REF ; Set the voltage value to Bandgap reference voltage V REF The corresponding data set is used as the control signal set of the current chip in the current temperature range; Take the intersection of the control signal sets of all the chips under test in the corresponding temperature range; The lookup table is constructed using the intersection of all temperature section control signal sets.

9. The bandgap reference circuit with full temperature range adaptive adjustment according to claim 7, characterized in that: According to the lookup table, the data is filtered, specifically: A lookup table is used to select one universal control signal from the intersection of each temperature segment control signal set to form the control data to be written.

10. The bandgap reference circuit with full temperature range adaptive adjustment according to claim 7, characterized in that: Write the control data, specifically: The control data is written into the memory.

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