Bandgap reference circuit with high-order temperature compensation
Patent Information
- Application Number
- CN202522282362.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-28
- Publication Date
- 2026-09-01
- Estimated Expiration
- 2035-10-28
AI Technical Summary
[0004]本实用新型提供一种带有高阶温度补偿的带隙基准电路，以解决现有技术中高阶温度补偿电路复杂、影响一阶温度补偿的精度的问题
[0014]本实用新型提供的带有高阶温度补偿的带隙基准电路，通过第一差分放大器的同相端与第一电阻之间的节点A以及其反相端与第一双极型晶体管之间的节点B拉出高阶温度补偿电流，电路简单，简化了高阶温度补偿的带隙基准电路，并且高阶温度补偿电流是从一阶带隙基准电路中拉出，而不是灌入一阶带隙基准电路中，将高阶温度补偿电流与低阶温度补偿电流分开来，不会对低阶温度补偿的精度产生影响，进而补偿精度高。
Smart Images
Figure CN224708394U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of integrated circuits, and in particular to a bandgap reference circuit with high-order temperature compensation. Background Technology
[0002] A bandgap reference circuit is a circuit that provides a constant voltage output and is essential for many analog and mixed-signal electronic devices. In analog and mixed-signal circuits such as power management controllers, oscillators, and phase-locked loops, a bandgap reference provides these devices with a voltage reference signal that has a low temperature coefficient and a high power supply rejection ratio, unaffected by temperature, process, and power supply voltage variations. This is a prerequisite for ensuring the chip's anti-interference capability and long-term reliability, and for ensuring the stable operation of the circuit in different environments.
[0003] Existing bandgap reference circuits for implementing high-order temperature compensation are relatively complex. Furthermore, high-order temperature compensation involves injecting current from the node into the bandgap reference circuit, allowing the current to flow into the BJT transistor. The results of first-order temperature compensation are significantly affected by process deviations and matching accuracy. Utility Model Content
[0004] This invention provides a bandgap reference circuit with high-order temperature compensation to solve the problem that high-order temperature compensation circuits in the prior art are complex and affect the accuracy of first-order temperature compensation.
[0005] To solve the above-mentioned technical problems, this utility model is achieved through the following technical solution: This invention provides a bandgap reference circuit with high-order temperature compensation, comprising: A first-order bandgap reference circuit includes: a first differential amplifier, a first transistor, a first resistor, a second resistor, a third resistor, a first bipolar transistor, and a second bipolar transistor; the non-inverting input of the first differential amplifier is connected to one end of the first resistor; node A between the first differential amplifier and the first resistor is connected to one end of the second resistor; the inverting input of the first differential amplifier is connected to the emitter of the first bipolar transistor; node B between the first differential amplifier and the first bipolar transistor is connected to one end of the third resistor; the output of the first differential amplifier is connected to the gate of the first transistor; the source of the first transistor is connected to VDD; the other end of the first resistor is connected to the emitter of the second bipolar transistor; the base and collector of the first bipolar transistor and the base and collector of the second bipolar transistor are connected to GND; the other end of the second resistor and the other end of the third resistor are connected to the drain of the first transistor and serve as the output of the reference voltage. A high-order temperature compensation circuit is connected to the first-order bandgap reference circuit and is used to generate a high-order temperature compensation current based on the first-order bandgap reference circuit. The high-order temperature compensation current is output from the node A and the node B respectively.
[0006] Optionally, the high-order temperature compensation circuit includes: A high-order temperature-compensated current generating unit is connected to the first-order bandgap reference circuit. The current access unit, which is connected to the high-order temperature compensation current generating unit, also includes: two compensation current access terminals, which are respectively connected to node A and node B.
[0007] Optionally, the current access unit includes: a second transistor, a third transistor, and a fourth transistor; the gate of the second transistor is interconnected with the gate of the third transistor and the gate of the fourth transistor; the source of the second transistor, the source of the third transistor, and the source of the fourth transistor are connected to GND; the drain of the second transistor is connected to node A; the drain of the third transistor is connected to node B; and the drain of the fourth transistor and its gate are interconnected to serve as the output terminal of the current access unit. The second transistor has the same dimensions as the third transistor.
[0008] Optionally, the high-order temperature-compensated current generating unit includes: a fifth transistor, a sixth transistor, a seventh transistor, an eighth transistor, a second differential amplifier, a third differential amplifier, a fourth resistor, a fifth resistor, and a third bipolar transistor; wherein, The drain of the fifth transistor is connected to the output terminal of the current access unit. The non-inverting terminal of the second differential amplifier is interconnected with the drain of the sixth transistor and one end of the fourth resistor. The output terminal of the second differential amplifier is interconnected with the gate of the fifth transistor and the gate of the sixth transistor. The source of the fifth transistor and the source of the sixth transistor are connected to VDD. The drain of the seventh transistor is interconnected with the emitter of the third bipolar transistor and the other end of the fourth resistor. The non-inverting input of the third differential amplifier is interconnected with the drain of the eighth transistor and one end of the fifth resistor. The output of the third differential amplifier is interconnected with the gate of the seventh transistor and the gate of the eighth transistor. The source of the seventh transistor and the source of the eighth transistor are connected to VDD. The base and collector of the third bipolar transistor and the other end of the fifth resistor are connected to GND. The inverting input of the second differential amplifier is connected to the inverting input of the third differential amplifier, and then connected to the node between the first resistor and the second bipolar transistor.
[0009] Optionally, the fifth resistor has the same resistance value as the first resistor.
[0010] Optionally, the high-order temperature current generating unit includes: a ninth transistor, a tenth transistor, an eleventh transistor, a twelfth transistor, a current source, a fourth differential amplifier, a sixth resistor, and a fourth bipolar transistor; wherein, The drain of the ninth transistor is connected to the output terminal of the current input unit. The source of the ninth transistor, the source of the tenth transistor, the input terminal of the current source, the output terminal of the fourth differential amplifier, and the inverting terminal of the fourth differential amplifier are interconnected. The non-inverting terminal of the fourth differential amplifier is connected to the output terminal of the reference voltage. The gate of the ninth transistor is interconnected with the gate of the tenth transistor, the drain of the tenth transistor, and the drain of the eleventh transistor. The gate of the eleventh transistor is interconnected with the gate of the twelfth transistor, the drain of the twelfth transistor, and the output terminal of the current source. The source of the eleventh transistor is connected to one end of the sixth resistor. The source of the twelfth transistor is connected to the emitter of the fourth bipolar transistor. The base and collector of the fourth bipolar transistor and the other end of the sixth resistor are connected to GND.
[0011] Optionally, the resistance value of the sixth resistor is the same as that of the first resistor.
[0012] Optionally, the second resistor and the third resistor have the same resistance value.
[0013] Optionally, the second resistor and the third resistor have the same model number.
[0014] The bandgap reference circuit with high-order temperature compensation provided by this utility model draws out the high-order temperature compensation current through node A between the non-inverting input of the first differential amplifier and the first resistor, and node B between its inverting input and the first bipolar transistor. The circuit is simple, simplifying the high-order temperature compensation bandgap reference circuit. Furthermore, the high-order temperature compensation current is drawn from the first-order bandgap reference circuit, rather than being poured into the first-order bandgap reference circuit, thus separating the high-order temperature compensation current from the low-order temperature compensation current. This does not affect the accuracy of the low-order temperature compensation, resulting in high compensation accuracy. Attached Figure Description
[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0016] Figure 1 This is a schematic diagram of a bandgap reference circuit with high-order temperature compensation according to an embodiment of the present invention. Figure 2 A schematic diagram of a bandgap reference circuit with high-order temperature compensation according to another embodiment of this utility model. Explanation of reference numerals in the attached figures: 1- First-order bandgap reference circuit; 2-High-order temperature compensation circuit; 21-High-order temperature-compensated current generation unit; 22-Current input unit. Detailed Implementation
[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0018] In the description of this utility model, it should be understood that the terms "upper part", "lower part", "upper end", "lower end", "lower surface", "upper surface", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.
[0019] In the description of this utility model, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.
[0020] In the description of this utility model, "multiple" means multiple, such as two, three, four, etc., unless otherwise explicitly specified.
[0021] In the description of this utility model, unless otherwise expressly specified and limited, the term "connection" and other such terms should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral part; it can refer to a mechanical connection, an electrical connection, or a connection that allows communication between the components; it can refer to a direct connection or an indirect connection through an intermediate medium; it can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0022] The technical solution of this utility model will be described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.
[0023] In one embodiment, a bandgap reference circuit with high-order temperature compensation is provided, comprising: a first-order bandgap reference circuit 1 and a high-order temperature compensation circuit 2. Please refer to [reference needed]. Figure 1 Among them, the first-order bandgap reference circuit 1 is used for first-order temperature compensation, and the high-order temperature compensation circuit 2 is used for high-order temperature compensation.
[0024] Specifically, the first-order bandgap reference circuit 1 includes: a first differential amplifier A1, a first transistor M1, a first resistor R1, a second resistor R2, a third resistor R3, a first bipolar transistor Q1, and a second bipolar transistor Q2. In this circuit, the non-inverting input of the first differential amplifier A1 is connected to one end of the first resistor R1; node A between the first differential amplifier A1 and the first resistor R1 is connected to one end of the second resistor R2; the inverting input of the first differential amplifier A1 is connected to the emitter of the first bipolar transistor Q1; node B between the first differential amplifier A1 and the first bipolar transistor Q1 is connected to one end of the third resistor R3; the output terminal of the first differential amplifier A1 is connected to the gate of the first transistor M1; the source of the first transistor M1 is connected to VDD; the other end of the first resistor R1 is connected to the emitter of the second bipolar transistor Q2; the base and collector of the first bipolar transistor Q1 and the base and collector of the second bipolar transistor Q2 are connected to GND; and the other ends of the second resistor R2 and the third resistor R3 are connected to the drain of the first transistor M1 and serve as the output terminal VREF of the reference voltage. A high-order temperature compensation circuit 2 is connected to the first-order bandgap reference circuit 1 and is used to generate a high-order temperature compensation current based on the first-order bandgap reference circuit 1. The high-order temperature compensation current is drawn from nodes A and B, respectively.
[0025] In practice, the base and collector of the first bipolar transistor Q1 and the base and collector of the second bipolar transistor Q2 are connected to GND. They can be connected to GND separately or connected to each other and then connected to GND.
[0026] In this embodiment, the high-order temperature compensation circuit 2 includes a high-order temperature compensation current generation unit 21 and a current access unit 22. The high-order temperature compensation current generation unit 21 is connected to a first-order bandgap reference circuit, and the current access unit 22 is connected to the high-order temperature compensation current generation unit 21. It also includes two compensation current access terminals, respectively used to connect to node A and node B.
[0027] In this embodiment, the current access unit 22 includes a second transistor M2, a third transistor M3, and a fourth transistor M4. The gate of the second transistor M2 is interconnected with the gates of the third transistor M3 and the fourth transistor M4. The sources of the second transistor M2, the third transistor M3, and the fourth transistor M4 are connected to GND. The drain of the second transistor M2 is connected to node A, the drain of the third transistor M3 is connected to node B, and the drain of the fourth transistor M4 is interconnected with its gate and then connected to the high-order temperature compensation current generating unit 21. Since the second transistor M2 and the third transistor M3 have the same size, the current at both access terminals of the current access unit is the same.
[0028] In practice, the source of the second transistor M2, the source of the third transistor M3, and the source of the fourth transistor M4 are connected to GND. They can be connected to GND individually or connected to each other and then connected to GND.
[0029] In practice, the second resistor R2 and the third resistor R3 have the same resistance value.
[0030] Preferably, the second resistor R2 and the third resistor R3 are of the same type, which can avoid the influence of different resistor materials, resistance values, etc. on the temperature drift of the circuit.
[0031] In the above embodiment, the circuit works as follows: assuming the area ratio of Q1 to Q2 is 1:N, and the resistance of R1 is R... A The resistance values of R2 and R3 are R B V of the first and second bipolar transistors BE It has a negative temperature coefficient. It is a negative temperature coefficient, where, Let be the voltage at node B. Let be the voltage at node A. , The thermal voltage is ; adjusted by a first-order bandgap reference circuit. By adjusting , This allows us to obtain results that are independent of the temperature coefficient. .but The second derivative with respect to temperature is negative, i.e. As the temperature decreases at an increasingly rapid rate, a first-order bandgap reference circuit can only compensate for the first-order temperature. A higher-order temperature compensation circuit introduces a higher-order positive temperature coefficient to offset this. The resulting high-order negative temperature coefficient, the current at the two input terminals of the current input unit. It has a positive temperature coefficient, at this time .
[0032] In this embodiment, the high-order temperature compensation current generating unit 21 comprises: a fifth transistor M5, a sixth transistor M6, a seventh transistor M7, an eighth transistor M8, a second differential amplifier A2, a third differential amplifier A3, a fourth resistor R4, a fifth resistor R5, and a third bipolar transistor Q3. Wherein, the drain of the fifth transistor M5 is connected to the output terminal of the current access unit, the non-inverting terminal of the second differential amplifier A2 is interconnected with the drain of the sixth transistor M6 and one end of the fourth resistor R4, the output terminal of the second differential amplifier A2 is interconnected with the gate of the fifth transistor M5 and the gate of the sixth transistor M6, and the sources of the fifth transistor M5 and the sixth transistor M6 are connected to VDD; the drain of the seventh transistor M7 is interconnected with the emitter of the third bipolar transistor Q3 and the other end of the fourth resistor R4, the non-inverting terminal of the third differential amplifier A3 is interconnected with the drain of the eighth transistor M8 and one end of the fifth resistor R5, the output terminal of the third differential amplifier A3 is interconnected with the gate of the seventh transistor M7 and the gate of the eighth transistor M8, the sources of the seventh transistor M7 and the eighth transistor M8 are connected to VDD, the base and collector of the third bipolar transistor Q3 and the other end of the fifth resistor R5 are connected to GND; the inverting terminal of the second differential amplifier A2 is connected to the inverting terminal of the third differential amplifier A3, and then connected to the node between the first resistor R1 and the second bipolar transistor Q2.
[0033] According to an embodiment, the resistance of the fifth resistor R5 is equal to that of the first resistor R1, the size of the seventh transistor M7 is equal to that of the eighth transistor M8, and the size of the sixth transistor M6 is equal to that of the fifth transistor M5. The working principle of the high-order temperature compensation current generating unit 21 is as follows: due to the existence of A3, the voltage across R5 is equal to the voltage across Q2, and since the size of M7 is the same as that of M8, the currents through R5 and Q3 are equal; due to the existence of A2, the voltage at the right side of R4 is equal to the voltage of Q2; meanwhile, since the sizes of M6 and M5 are the same, the currents flowing through R4 and M4 are the same; by adjusting the resistance of R4, the high-order temperature compensation current IA can be obtained. Assuming that the area ratio of Q1, Q2 and Q3 is 1:N:M, where N<M, we obtain .
[0034] According to an embodiment, the base and collector of the third bipolar transistor Q3 and the other end of the fifth resistor R5 are connected to GND, which may be connected to GND separately, or may be connected to each other and then connected to GND.
[0035] In another embodiment, a bandgap reference circuit with high-order temperature compensation is provided, please refer to Figure 2 , which differs from the embodiment of Figure 1 in the high-order temperature compensation current generating unit, and other parts are the same as those in the embodiment of Figure 1 , and will not be repeated here.
[0036] Specifically, the high-order temperature-compensated current generating unit 21 includes: a ninth transistor M9, a tenth transistor M10, an eleventh transistor M11, a twelfth transistor M12, a current source S, a fourth differential amplifier A4, a sixth resistor R6, and a fourth bipolar transistor Q4. In this configuration, the drain of the ninth transistor M9 is connected to the output terminal of the current input unit. The source of the ninth transistor M9, the source of the tenth transistor M10, the input terminal of the current source S, the output terminal of the fourth differential amplifier A4, and the inverting terminal of the fourth differential amplifier A4 are interconnected. The non-inverting terminal of the fourth differential amplifier A4 is connected to the output terminal VREF of the reference voltage. The gate of the ninth transistor M9 is interconnected with the gate of the tenth transistor M10, the drain of the tenth transistor M10, and the drain of the eleventh transistor M11. The gate of the eleventh transistor M11 is interconnected with the gate of the twelfth transistor M12, the drain of the twelfth transistor M12, and the output terminal of the current source S. The source of the eleventh transistor M11 is connected to one end of the sixth resistor R6. The source of the twelfth transistor M12 is connected to the emitter of the fourth bipolar transistor Q4. The base and collector of the fourth bipolar transistor Q4 and the other end of the sixth resistor R6 are connected to GND.
[0037] In practice, the resistance value of the sixth resistor R6 is the same as that of the first resistor R1. The formula for the current IA in this embodiment is: .
[0038] In practice, the base and collector of the fourth bipolar transistor Q4 and the other end of the sixth resistor R6 are connected to GND. They can be connected to GND separately or connected to each other and then connected to GND.
[0039] In the description of this specification, the references to terms such as "an embodiment," "an example," "a specific implementation process," and "an example" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.
Claims
1. A bandgap reference circuit with high-order temperature compensation, characterized in that, include: A first-order bandgap reference circuit includes: a first differential amplifier, a first transistor, a first resistor, a second resistor, a third resistor, a first bipolar transistor, and a second bipolar transistor; the non-inverting input of the first differential amplifier is connected to one end of the first resistor; node A between the first differential amplifier and the first resistor is connected to one end of the second resistor; the inverting input of the first differential amplifier is connected to the emitter of the first bipolar transistor; node B between the first differential amplifier and the first bipolar transistor is connected to one end of the third resistor; the output of the first differential amplifier is connected to the gate of the first transistor; the source of the first transistor is connected to VDD; the other end of the first resistor is connected to the emitter of the second bipolar transistor; the base and collector of the first bipolar transistor and the base and collector of the second bipolar transistor are connected to GND; the other end of the second resistor and the other end of the third resistor are connected to the drain of the first transistor and serve as the output of the reference voltage. A high-order temperature compensation circuit, which is connected to the first-order bandgap reference circuit, is used to generate a high-order temperature compensation current based on the first-order bandgap reference circuit. The high-order temperature compensation current is drawn out from the node A and the node B respectively.
2. The bandgap reference circuit according to claim 1, characterized in that, The high-order temperature compensation circuit includes: A high-order temperature-compensated current generating unit is connected to the first-order bandgap reference circuit. The current access unit, which is connected to the high-order temperature compensation current generating unit, also includes: two compensation current access terminals, which are respectively connected to node A and node B.
3. The bandgap reference circuit according to claim 2, characterized in that, The current access unit includes: a second transistor, a third transistor, and a fourth transistor; the gate of the second transistor is interconnected with the gate of the third transistor and the gate of the fourth transistor; the source of the second transistor, the source of the third transistor, and the source of the fourth transistor are connected to GND; the drain of the second transistor is connected to node A; the drain of the third transistor is connected to node B; and the drain of the fourth transistor and its gate are interconnected to serve as the output terminal of the current access unit. The second transistor has the same dimensions as the third transistor.
4. The bandgap reference circuit according to claim 2, characterized in that, The high-order temperature-compensated current generating unit includes: a fifth transistor, a sixth transistor, a seventh transistor, an eighth transistor, a second differential amplifier, a third differential amplifier, a fourth resistor, a fifth resistor, and a third bipolar transistor; wherein, The drain of the fifth transistor is connected to the output terminal of the current access unit. The non-inverting terminal of the second differential amplifier is interconnected with the drain of the sixth transistor and one end of the fourth resistor. The output terminal of the second differential amplifier is interconnected with the gate of the fifth transistor and the gate of the sixth transistor. The source of the fifth transistor and the source of the sixth transistor are connected to VDD. The drain of the seventh transistor is interconnected with the emitter of the third bipolar transistor and the other end of the fourth resistor. The non-inverting input of the third differential amplifier is interconnected with the drain of the eighth transistor and one end of the fifth resistor. The output of the third differential amplifier is interconnected with the gate of the seventh transistor and the gate of the eighth transistor. The source of the seventh transistor and the source of the eighth transistor are connected to VDD. The base and collector of the third bipolar transistor and the other end of the fifth resistor are connected to GND. The inverting input of the second differential amplifier is connected to the inverting input of the third differential amplifier, and then connected to the node between the first resistor and the second bipolar transistor.
5. The bandgap reference circuit according to claim 4, characterized in that, The fifth resistor has the same resistance value as the first resistor.
6. The bandgap reference circuit according to claim 2, characterized in that, The high-order temperature current generating unit includes: a ninth transistor, a tenth transistor, an eleventh transistor, a twelfth transistor, a current source, a fourth differential amplifier, a sixth resistor, and a fourth bipolar transistor; wherein, The drain of the ninth transistor is connected to the output terminal of the current input unit. The source of the ninth transistor, the source of the tenth transistor, the input terminal of the current source, the output terminal of the fourth differential amplifier, and the inverting terminal of the fourth differential amplifier are interconnected. The non-inverting terminal of the fourth differential amplifier is connected to the output terminal of the reference voltage. The gate of the ninth transistor is interconnected with the gate of the tenth transistor, the drain of the tenth transistor, and the drain of the eleventh transistor. The gate of the eleventh transistor is interconnected with the gate of the twelfth transistor, the drain of the twelfth transistor, and the output terminal of the current source. The source of the eleventh transistor is connected to one end of the sixth resistor. The source of the twelfth transistor is connected to the emitter of the fourth bipolar transistor. The base and collector of the fourth bipolar transistor and the other end of the sixth resistor are connected to GND.
7. The bandgap reference circuit according to claim 6, characterized in that, The resistance value of the sixth resistor is the same as that of the first resistor.
8. The bandgap reference circuit according to any one of claims 1 to 7, characterized in that, The second resistor has the same resistance value as the third resistor.
9. The bandgap reference circuit according to claim 8, characterized in that, The second resistor has the same model number as the third resistor.