A hybrid bandgap reference with current driving capability and integrated circuit

Abstract

The application provides a hybrid bandgap reference with current driving capability and an integrated circuit, and relates to the field of integrated circuits.A current-mode bandgap reference core is connected with a voltage-mode bandgap reference core through a second resistance trimming network, the current-mode bandgap reference core generates a first-order zero-temperature drift current, and the first-order zero-temperature drift current is a current independent of temperature;the voltage-mode bandgap reference core compensates for the nonlinearity of a bandgap reference voltage based on the first-order zero-temperature drift current by adjusting the resistance of a first resistance trimming network and a second resistance trimming network, and generates a current driving capability of a milliamper level or above through a driving module.The application creatively proposes a V BE The hybrid bandgap reference with high-order term compensation and current-voltage mode achieves the purpose of low temperature drift design and has good current driving capability, can be applied to high-precision AD and other application scenarios requiring low temperature drift and current driving capability, and reduces trimming cost.

Description

Technical Field

[0001] This invention relates to the field of integrated circuits, and more particularly to a hybrid bandgap reference and integrated circuit with current-driven capability. Background Technology

[0002] Traditional bandgap references only have first-order curvature compensation, resulting in significant temperature drift. To reduce temperature drift, various higher-order compensation techniques have been applied to bandgap references. However, due to circuit structure limitations, traditional bandgap references cannot be directly connected to resistive loads at their output terminals. This is because the load would divert some current, affecting the core function of the bandgap reference circuit and preventing the generation of a stable reference voltage.

[0003] Therefore, a unity-gain buffer operational amplifier or an LDO (Low Dropout Regulator) is usually connected to the output of the bandgap reference source so that the bandgap reference source can be used in applications such as ADCs that require a bandgap reference and have a certain current driving capability.

[0004] However, both output buffer op-amps and LDOs introduce new temperature drift, thus requiring an additional resistor adjustment network at the LDO or unity-gain buffer op-amp (i.e., adding a resistor adjustment network on top of the traditional resistor adjustment network included in the bandgap reference structure). This significantly increases the adjustment cost. Without adding an additional resistor adjustment network, the LDO or unity-gain buffer op-amp introduces new temperature drift, and not using a unity-gain buffer op-amp or LDO would prevent the bandgap reference source from being used in applications requiring a bandgap reference and a certain current drive capability, such as ADCs.

[0005] Therefore, there is an urgent need to propose a bandgap reference that can have current driving capability without requiring an additional resistor adjustment network. Summary of the Invention

[0006] In view of the above problems, the present invention is proposed to provide a hybrid bandgap reference and integrated circuit with current drive capability that solves or partially solves the above problems.

[0007] The first aspect of this invention provides a hybrid bandgap reference with current-driven capability, the hybrid bandgap reference comprising: a current-mode bandgap reference core, a voltage-mode bandgap reference core, and a resistor adjustment network;

[0008] The voltage-mode bandgap reference core includes a driving module, which includes a first resistor adjustment network.

[0009] The current-mode bandgap reference core is connected to the voltage-mode bandgap reference core through a second resistor adjustment network. The current-mode bandgap reference core generates a first-order zero-temperature drift current, which is a temperature-independent current.

[0010] The voltage-mode bandgap reference core is based on the first-order zero-temperature drift current. By adjusting the resistance of the first resistor adjustment network and the resistance of the second resistor adjustment network, it compensates for the nonlinearity of the bandgap reference voltage and generates a current driving capability of milliampere level or above through the driving module.

[0011] Optionally, the driving module further includes: a first resistor, a second resistor, an amplifier, and a driving unit; the voltage mode bandgap reference core further includes: a startup circuit, a third resistor, a first transistor, and a second transistor;

[0012] The startup circuit is connected between the negative terminal of the amplifier and the power supply terminal;

[0013] One end of the driving unit is connected to the power supply terminal, and the other two ends are respectively connected to the input terminal of the first resistor adjustment network and the output terminal of the amplifier.

[0014] The output terminal of the first resistor adjustment network is connected to the first terminal of the first resistor and the first terminal of the second resistor, respectively.

[0015] The second end of the first resistor is connected to the first end of the third resistor and the positive terminal of the amplifier, respectively.

[0016] The second end of the second resistor is connected to the negative terminal of the amplifier and the emitter of the first transistor, respectively.

[0017] The second end of the third resistor is connected to the emitter of the second transistor;

[0018] The base of the first transistor is connected to its own collector and grounded;

[0019] The base of the second transistor is connected to its own collector and grounded.

[0020] Optionally, the driving unit includes: a driving MOS transistor;

[0021] The first terminal of the driving MOS transistor is connected to the power supply terminal, the second terminal is connected to the output terminal of the amplifier, and the third terminal is connected to the input terminal of the first resistor adjustment network, and the third terminal outputs a bandgap reference voltage.

[0022] Optionally, the driving unit further includes: a Miller compensation capacitor;

[0023] One end of the Miller compensation capacitor is connected to the second end of the driving MOS transistor;

[0024] The other end of the Miller compensation capacitor is connected to the third end of the driving MOS transistor.

[0025] Optionally, the second resistor adjustment network includes: a first sub-resistance adjustment network and a second sub-resistance adjustment network;

[0026] The first terminal of the first sub-resistor tuning network receives the first-order zero-temperature drift current, and the second terminal is connected to the negative terminal of the amplifier.

[0027] The first end of the second sub-resistor adjustment network receives the first-order zero-temperature drift current, and the second end is connected to the positive terminal of the amplifier.

[0028] Optionally, the current-mode bandgap reference core includes: a third transistor;

[0029] The emitter of the third transistor receives the first-order zero-temperature drift current, and its base is connected to its own collector and grounded.

[0030] The emitter area ratio of the first transistor, the second transistor, and the third transistor is 1:N:1.

[0031] Optionally, the resistance value of the first resistor is equal to the resistance value of the second resistor, but different from the resistance value of the third resistor.

[0032] Optionally, when unloaded, the output current at the third terminal of the driving MOS transistor flows only through the first resistor adjustment network;

[0033] When there is load current, the voltage at the second terminal of the driving MOSFET is pulled low, and the output current at the third terminal of the driving MOSFET increases, generating a current driving capability of milliampere level or above to provide additional current to the load.

[0034] Optionally, the second terminal of the driving MOS transistor has a major pole, and the third terminal of the driving MOS transistor has a minor major pole. The Miller compensation capacitor is used to separate the major pole and the minor major pole.

[0035] A second aspect of the present invention provides an integrated circuit, the integrated circuit including a hybrid bandgap reference having current-driven capability as described in any of the first aspects above.

[0036] The present invention provides a hybrid bandgap reference with current driving capability, comprising: a current-mode bandgap reference core, a voltage-mode bandgap reference core, and a resistor adjustment network; the voltage-mode bandgap reference core comprises: a driving module, and the driving module comprises: a first resistor adjustment network.

[0037] The current-mode bandgap reference core is connected to the voltage-mode bandgap reference core through a second resistor adjustment network. The current-mode bandgap reference core generates a first-order zero-temperature drift current, which is a temperature-independent current.

[0038] The voltage-mode bandgap reference core is based on first-order zero-temperature-drift current. By adjusting the resistance of the first resistor adjustment network and the resistance of the second resistor adjustment network, it compensates for the nonlinearity of the bandgap reference voltage and generates a current driving capability of milliampere level or above through the drive module.

[0039] The hybrid bandgap reference with current-driven capability proposed in this invention differs from the current traditional structure with unity-gain buffer operational amplifiers or LDOs and additional resistor adjustment networks. It creatively proposes a structure based on V... BE The high-order term compensated current-voltage hybrid bandgap reference uses the current model bandgap reference to provide a first-order zero-temperature drift current as the bias of the transistor, and combines the current model bandgap reference and the voltage model bandgap reference by utilizing the resistor adjustment network contained in the bandgap reference itself.

[0040] By adjusting the resistance of the resistor adjustment network, the nonlinearity of the bandgap reference voltage is compensated, while the driving module generates a current driving capability in the milliampere level or above. This allows the invention to achieve the goal of low temperature drift design while possessing good current driving capability. It can be applied to applications requiring both low temperature drift and current driving capability, such as high-precision AD converters. Furthermore, it avoids the need for an additional resistor adjustment network when connecting an LDO or unity-gain buffer op-amp, reducing adjustment costs and demonstrating high practicality. Attached Figure Description

[0041] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a schematic diagram of the structure of a traditional reference voltage output via an LDO;

[0043] Figure 2 This is a schematic diagram of the traditional reference voltage output via an RVB (Reference Voltage Buffer);

[0044] Figure 3 This is a schematic diagram of a hybrid bandgap reference with current-driven capability in an embodiment of the present invention;

[0045] Figure 4 This is the corresponding embodiment of the present invention. Figure 3A simplified circuit diagram of the model. Detailed Implementation

[0046] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] The inventors discovered that the basic principle of a conventional bandgap reference voltage source circuit for outputting a reference voltage that is almost unaffected by temperature changes is to superimpose a voltage with a positive temperature coefficient that increases with temperature and a voltage with a negative temperature coefficient that decreases with temperature, thereby canceling out the temperature coefficients of the two. The resulting superimposed voltage is a reference voltage that is essentially independent of temperature.

[0048] Further research by the inventors revealed that while the reference voltage circuit can generate a high-precision and highly interference-resistant voltage when parameters such as input voltage and ambient temperature change, it lacks the driving capability for load currents with large variations. The loads driven by the reference voltage circuit are typically small currents, often below the milliampere level.

[0049] To address the aforementioned issues, the inventors discovered that currently, a unity-gain buffer operational amplifier or an LDO is connected to the output of the bandgap reference source. LDOs are a type of voltage regulator that can drive load currents up to several amperes while consuming minimal power, effectively reducing the heat dissipation burden on the chip. Furthermore, LDOs respond quickly to non-drastic load current surges. Therefore, LDOs are typically connected to the output of the reference source to enable its application in scenarios requiring current-driven capabilities.

[0050] Reference Figure 1 The diagram shown illustrates the structure of the reference voltage output via an LDO. The bandgap reference module generates a high-precision reference voltage (i.e., the reference voltage V). REF The feedback network detects the output voltage and feeds it back to the input of the error amplifier. The error amplifier compares the feedback voltage with the reference voltage and generates an error signal. The regulating transistor MP adjusts its current according to the error signal, so that the LDO maintains the output voltage within an acceptable range near the target value, and the output voltage is to a certain extent unaffected by changes in environmental conditions such as noise, temperature, load current and power supply voltage.

[0051] However, LDOs all introduce new temperature drift, so an additional resistor adjustment network needs to be added at the LDO. Figure 1 , 2 (For the sake of simplicity, the additional resistor adjustment network is not shown in the diagram; otherwise, the reference voltage would change with environmental conditions such as noise, temperature, load current, and power supply voltage.)

[0052] The inventors also discovered another common practice, which involves connecting a reference voltage buffer (i.e., a unity-gain buffer op-amp) after the bandgap reference to provide drive. For example... Figure 2 The diagram shows the structure of the reference voltage output via RVB (Reference Voltage Buffer). The reference voltage is generated by the bandgap reference, and a replication branch is formed using MN1 transistor. The operating state of the branch containing MN transistor is replicated in a matched manner to obtain the required reference voltage.

[0053] This isolates the branch containing the reference voltage MN1 from the driver stage, ensuring that voltage fluctuations at the reference voltage output node do not affect the operation of the feedback loop and improving setup performance. The driving capability of RVB is mainly reflected in its large-signal driving capability and small-signal driving capability. The large-signal driving capability mainly relies on the output stage current, while the small-signal driving capability relies on the RC characteristics of the output poles.

[0054] To account for manufacturing errors, a resistor adjustment network is typically added to the bandgap reference to reduce V. REF The temperature drift of the op-amp in LDO and RVB varies with temperature (i.e., new temperature drift is introduced), which in turn affects V. OUT (i.e., the output reference voltage V) REF The temperature coefficient of V is important; therefore, to obtain a V with driving capability and low temperature drift... OUT Additional resistor adjustment networks need to be added to the LDO and RVB circuits to adjust V. OUT Adjusting the temperature drift increases the chip area, making the chip testing process more complex.

[0055] Without adding an additional resistor adjustment network, LDOs or RVBs introduce new temperature drift. Not using unit RVBs or LDOs would prevent bandgap reference sources from being used in applications such as ADCs that require bandgap references and have a certain current drive capability.

[0056] To address the aforementioned problems, the inventors have creatively proposed a hybrid bandgap reference and integrated circuit with current-driven capability according to the present invention. The following provides a detailed explanation and description of the hybrid bandgap reference and integrated circuit with current-driven capability proposed in this invention.

[0057] The present invention proposes a hybrid bandgap reference with current driving capability, comprising: a current-mode bandgap reference core, a voltage-mode bandgap reference core, and a resistor adjustment network; the voltage-mode bandgap reference core comprises: a driving module, and the driving module comprises: a first resistor adjustment network.

[0058] The current-mode bandgap reference core is connected to the voltage-mode bandgap reference core through a second resistor adjustment network. This innovative use of the resistor adjustment network combines the current-mode and voltage-mode bandgap reference cores. (The last sentence appears to be incomplete and possibly refers to a different topic.) BE Nonlinear compensation bandgap references require a first-order zero-temperature drift current to provide bias for BJTs (i.e., transistors). However, in traditional voltage model bandgap references, the current is PTAT (proportional to temperature). Therefore, this invention generates a first-order zero-temperature drift current from the core of a current-mode bandgap reference to provide bias for the BJT, and the first-order zero-temperature drift current is a temperature-independent current.

[0059] The voltage-mode bandgap reference core is based on first-order zero-temperature drift current. By adjusting the resistance of the first resistor adjustment network and the resistance of the second resistor adjustment network, the nonlinearity of the bandgap reference voltage is compensated. At the same time, the driving module generates a current driving capability of milliampere level or above.

[0060] In some possible embodiments, the driving module further includes: a first resistor, a second resistor, an amplifier, and a driving unit; the voltage mode bandgap reference core further includes: a startup circuit, a third resistor, a first transistor, and a second transistor.

[0061] The startup circuit is connected between the negative terminal of the amplifier and the power supply terminal; one end of the drive unit is connected to the power supply terminal, and the other two ends are connected to the input terminal of the first resistor adjustment network and the output terminal of the amplifier, respectively; the output terminal of the first resistor adjustment network is connected to the first terminal of the first resistor and the first terminal of the second resistor, respectively.

[0062] The second end of the first resistor is connected to the first end of the third resistor and the positive terminal of the amplifier, respectively; the second end of the second resistor is connected to the negative terminal of the amplifier and the emitter of the first transistor, respectively; the second end of the third resistor is connected to the emitter of the second transistor; the base of the first transistor is connected to its own collector and grounded; the base of the second transistor is connected to its own collector and grounded.

[0063] For the drive module, any circuit or component that can provide current to the first resistor adjustment network under no-load conditions and increase the output current under load conditions, providing additional current to the load, is acceptable. A preferred choice for the drive unit is:

[0064] The driving unit includes: a driving MOSFET; the first terminal of the driving MOSFET is connected to the power supply terminal, the second terminal is connected to the output terminal of the amplifier, the third terminal is connected to the input terminal of the first resistor adjustment network, and the third terminal outputs a bandgap reference voltage.

[0065] Since the driving MOSFET operates under the action of a negative feedback loop, there is a dominant pole at the second terminal of the driving MOSFET and a secondary dominant pole at the third terminal. In order to separate the two, the inventors creatively proposed to use Miller compensation capacitors to separate the dominant pole and the secondary dominant pole.

[0066] Therefore, the driving unit also includes: a Miller compensation capacitor; one end of the Miller compensation capacitor is connected to the second terminal of the driving MOSFET; the other end of the Miller compensation capacitor is connected to the third terminal of the driving MOSFET. In summary, the driving MOSFET, Miller compensation capacitor, first resistor adjustment network, first resistor, second resistor, and amplifier constitute a negative feedback loop, which can provide milliampere-level or higher current driving capability.

[0067] Since the amplifier has two branches with positive and negative terminals, the second resistor adjustment network connected to it includes: a first sub-resistor adjustment network and a second sub-resistor adjustment network; the first terminal of the first sub-resistor adjustment network receives a first-order zero-temperature drift current, and the second terminal is connected to the negative terminal of the amplifier; the first terminal of the second sub-resistor adjustment network receives a first-order zero-temperature drift current, and the second terminal is connected to the positive terminal of the amplifier.

[0068] To better illustrate the hybrid bandgap reference with current-driven capability proposed in this invention, refer to... Figure 3 The diagram shows a schematic representation of a hybrid bandgap reference with current-driven capability in an embodiment of the present invention. Figure 3 An example is the PMOS transistor MP and the Miller capacitor C. C Let's take an example to illustrate.

[0069] Figure 3 The dashed box 10 on the left represents the current-mode bandgap reference core, and the dashed box 20 on the right represents the voltage-mode bandgap reference core. Both are connected by a second resistor adjustment network R. NL Connections. Start-Up indicates the startup circuit, meaning there is one startup circuit in each of the two bandgap reference cores. VDDA represents the power supply terminal, and VSSA represents ground.

[0070] The current-mode bandgap reference core generates a first-order zero-temperature-drift current as the bias of its transistors. Specifically, the third transistor Q3 in the current-mode bandgap reference core carries a temperature-independent first-order zero-temperature-drift current I3, and the first transistor Q1 in the voltage-mode bandgap reference core carries a PTAT current.

[0071] In the core of the voltage-mode bandgap reference, the Start-Up circuit is connected between the negative terminal of the amplifier Omp and the power supply terminal VDDA; the source of the driving MOSFET MP is connected to the power supply terminal VDDA, the drain is connected to the input drain of the first resistor adjustment network R1, and the gate is connected to the output terminal of the amplifier Omp.

[0072] Miller compensation capacitor C C A reference voltage V is connected between the gate and drain of the driving MOSFET MP, and the drain of the driving MOSFET MP outputs the reference voltage V. REF .

[0073] The output of the first resistor adjustment network R1 is connected to the first resistor R 2A First terminal, second resistor R 2B The first terminals are connected to the first resistor R. 2A The second terminal is connected to the first terminal of the third resistor R0 and the positive terminal of the amplifier Omp, respectively.

[0074] Second resistor R 2B The second terminal of the third resistor R0 is connected to the negative terminal of amplifier Omp and the emitter of the first transistor Q1, respectively; the second terminal of the third resistor R0 is connected to the emitter of the second transistor Q2; the base of the first transistor Q1 is connected to its own collector and grounded to VSSA; the base of the second transistor Q2 is connected to its own collector and grounded to VSSA. This drives the MOSFET MP and the Miller compensation capacitor C. C First resistor adjustment network R1, first resistor R 2A Second resistor R 2B The amplifier Omp forms a negative feedback loop (i.e., the aforementioned drive module), which can provide current drive capability at the milliampere level or above.

[0075] The current model bandgap reference provides a first-order zero-temperature-drift current I3, corresponding to Figure 3 The simplified model is Figure 4 The emitter area ratio of the first transistor Q1, the second transistor Q2, and the third transistor Q3 can be set to 1:N:1; the resistance of the first resistor R2A and the resistance of the second resistor R... 2B The resistance values ​​are the same, assuming they are all equal to the resistance value R2, that is: R 2A =R 2B =R2.

[0076] Combination Figure 3 , Figure 4 From the circuit structure, we can see that:

[0077] Since the current flowing through the first transistor Q1 is the PTAT current, the base-emitter voltage V of the first transistor Q1 is... BE1 It can be represented as:

[0078]

[0079] The current flowing through the third transistor Q3 is a temperature-independent current, and the base-emitter voltage V of the third transistor Q3 is... BE3 It can be represented as:

[0080]

[0081] The nonlinear compensation current I can then be derived. NL for:

[0082]

[0083] Ignoring the op-amp offset voltage, V can be obtained REF The expression is:

[0084]

[0085] If compensation V is required BE1 The nonlinear temperature coefficient term requires that:

[0086]

[0087] In the above formula, V g0 It is the bandgap voltage at -273℃, T r Let η be the required operating temperature of the circuit, and η be a process-dependent constant. Therefore, it can be seen that the nonlinearity of the bandgap reference voltage can be effectively compensated by selecting an appropriate resistor ratio.

[0088] The driving MOSFET MP can provide a large current to R1 and the current load. When unloaded, the drain current of the driving MOSFET MP flows through R1. When there is a load current I... L At this time, under the action of the negative feedback loop, the gate voltage of the driving MOSFET MP is pulled low, and its drain current I D Increase the current driving capability to the milliampere level or above, so as to provide additional current to the load.

[0089] To ensure that the reference has sufficient current drive capability and good load regulation, the driver MOSFET MP should be designed to have a large width-to-length ratio.

[0090] In the negative feedback loop, the gate of the driving MOSFET MP has a dominant pole, and the drain has a secondary dominant pole. A Miller compensation capacitor C is used. C Connecting the gate and drain of the driving MOSFET MP separates the primary and secondary poles, increasing the stability of the negative feedback loop.

[0091] To compensate for the adverse effects of process deviations on the accuracy of the reference voltage, the hybrid bandgap reference with current-driven capability proposed in this invention is designed with R1 and R2. NL Two resistance adjustment networks are used to correct the first-order temperature coefficient and higher-order nonlinear terms, respectively.

[0092] The hybrid bandgap reference with current driving capability proposed in this invention has been verified by simulation. The temperature drift of the reference voltage output by the bandgap reference is less than 2ppm / ℃, and it can provide mA-level driving current. It can be applied to high-precision AD and other application scenarios that require low temperature drift and current driving capability.

[0093] Based on the aforementioned hybrid bandgap reference with current-driven capability, this invention also proposes an integrated circuit, which includes the hybrid bandgap reference with current-driven capability as described above.

[0094] Through the above examples, the hybrid bandgap reference with current driving capability provided by the present invention includes: a current-mode bandgap reference core, a voltage-mode bandgap reference core, and a resistance adjustment network; the voltage-mode bandgap reference core includes: a driving module, and the driving module includes: a first resistance adjustment network.

[0095] The current-mode bandgap reference core is connected to the voltage-mode bandgap reference core through a second resistor adjustment network. The current-mode bandgap reference core generates a first-order zero-temperature drift current to provide bias for the transistor, and the first-order zero-temperature drift current is a temperature-independent current.

[0096] The voltage-mode bandgap reference core is based on first-order zero-temperature-drift current. By adjusting the resistance of the first resistor adjustment network and the resistance of the second resistor adjustment network, it compensates for the nonlinearity of the bandgap reference voltage and generates a current driving capability of milliampere level or above through the drive module.

[0097] The hybrid bandgap reference with current-driven capability proposed in this invention differs from the current traditional structure with unity-gain buffer operational amplifiers or LDOs and additional resistor adjustment networks. It creatively proposes a structure based on V... BE The high-order term compensated current-voltage hybrid bandgap reference uses the current model bandgap reference to provide a first-order zero-temperature drift current as the bias of the transistor, and combines the current model bandgap reference and the voltage model bandgap reference by utilizing the resistor adjustment network contained in the bandgap reference itself.

[0098] By adjusting the resistance of the resistor adjustment network, the nonlinearity of the bandgap reference voltage is compensated, while negative feedback generates a current drive capability in the milliampere level or higher. This allows the invention to achieve the goal of low temperature drift design while possessing good current drive capability. It can be applied to applications requiring both low temperature drift and current drive capability, such as high-precision AD converters. Furthermore, it avoids the need for an additional resistor adjustment network when connecting an LDO or unity-gain buffer op-amp, reducing adjustment costs and demonstrating high practicality.

[0099] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0100] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A hybrid bandgap reference with current-driven capability, characterized in that, The hybrid bandgap reference includes: a current-mode bandgap reference core, a voltage-mode bandgap reference core, and a second resistor adjustment network; The voltage-mode bandgap reference core includes: a driving module, a third resistor, a first transistor, and a second transistor. The driving module includes: a first resistor adjustment network, an amplifier, a driving unit, a first resistor, and a second resistor. The current-mode bandgap reference core is connected to the voltage-mode bandgap reference core through the second resistor adjustment network. The current-mode bandgap reference core generates a first-order zero-temperature drift current, which is a temperature-independent current. The voltage-mode bandgap reference core is based on the first-order zero-temperature drift current. By adjusting the resistance of the first resistor adjustment network and the resistance of the second resistor adjustment network, it compensates for the nonlinearity of the bandgap reference voltage and generates a current driving capability of milliampere level or above through the driving module. The output terminal of the first resistor adjustment network is connected to the first terminal of the first resistor and the first terminal of the second resistor, respectively; the second terminal of the first resistor is connected to the first terminal of the third resistor and the positive terminal of the amplifier, respectively; the second terminal of the second resistor is connected to the negative terminal of the amplifier and the emitter of the first transistor, respectively; the second terminal of the third resistor is connected to the emitter of the second transistor. The driving unit includes a driving MOSFET and a Miller compensation capacitor. The first terminal of the driving MOSFET is connected to the power supply terminal, the second terminal is connected to the output terminal of the amplifier, and the third terminal is connected to the input terminal of the first resistor adjustment network, and the third terminal outputs a bandgap reference voltage. One end of the Miller compensation capacitor is connected to the second terminal of the driving MOSFET, and the other end of the Miller compensation capacitor is connected to the third terminal of the driving MOSFET. The second resistor adjustment network includes: a first sub-resistor adjustment network and a second sub-resistor adjustment network; the first end of the first sub-resistor adjustment network receives the first-order zero-temperature drift current, and the second end is connected to the negative terminal of the amplifier; the first end of the second sub-resistor adjustment network receives the first-order zero-temperature drift current, and the second end is connected to the positive terminal of the amplifier.

2. The hybrid bandgap reference according to claim 1, characterized in that, The voltage-mode bandgap reference core also includes: a startup circuit; The startup circuit is connected between the negative terminal of the amplifier and the power supply terminal; The base of the first transistor is connected to its own collector and grounded; The base of the second transistor is connected to its own collector and grounded.

3. The hybrid bandgap reference according to claim 1, characterized in that, The current-mode bandgap reference core includes: a third transistor; The emitter of the third transistor receives the first-order zero-temperature drift current, and its base is connected to its own collector and grounded. The emitter area ratio of the first transistor, the second transistor, and the third transistor is 1:N:

1.

4. The hybrid bandgap reference according to claim 1, characterized in that, The resistance value of the first resistor is equal to the resistance value of the second resistor, but different from the resistance value of the third resistor.

5. The hybrid bandgap reference according to claim 1, characterized in that, When unloaded, the output current at the third terminal of the driving MOS transistor flows only through the first resistor adjustment network; When there is load current, the voltage at the second terminal of the driving MOSFET is pulled low, and the output current at the third terminal of the driving MOSFET increases, generating a current driving capability of milliampere level or above to provide additional current to the load.

6. The hybrid bandgap reference according to claim 1, characterized in that, The second terminal of the driving MOS transistor has a major pole, and the third terminal of the driving MOS transistor has a minor major pole. The Miller compensation capacitor is used to separate the major pole and the minor major pole.

7. An integrated circuit, characterized in that, The integrated circuit includes a hybrid bandgap reference with current-driven capability as described in any one of claims 1-6.

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