Band-gap reference voltage circuit and integrated circuit
Through the combination of operational amplifier OP, MOS tube M1, transistor Q1, resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, first-stage and second-stage temperature compensation modules, the problem of insufficient output voltage accuracy of the bandgap reference circuit is solved, and high-precision and low-noise reference voltage output is achieved.
Patent Information
- Application Number
- CN202423139169.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-19
- Publication Date
- 2025-10-21
- Estimated Expiration
- 2034-12-19
AI Technical Summary
Under the influence of non-ideal factors such as process parameter deviation and circuit mismatch, the output voltage accuracy of existing bandgap reference circuits is insufficient, making it difficult to provide a stable reference voltage.
A combination of an operational amplifier OP, a MOS tube M1, a transistor Q1, a transistor Q2, resistors R1, R2, R3, R4, R5, a first-stage temperature compensation module, and a second-stage temperature compensation module is adopted. Temperature compensation is achieved through a resistor array controlled by a digital circuit and a subthreshold self-bias circuit, thereby reducing noise and power consumption and improving the accuracy of the output reference voltage.
It achieves the output of high-precision reference voltage in a wide temperature range, reduces noise and power consumption, and improves the stability and accuracy of the circuit.
Smart Images
Figure CN223461814U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to integrated circuit analog circuit design technical field, especially related to a band gap reference voltage circuit and integrated circuit. BACKGROUND
[0002] The band gap reference circuit is the most common and important integrated circuit module in the analog integrated circuit design. Its function is to generate a stable voltage source as a reference voltage for other modules to use as a reference voltage. The band gap voltage reference circuit is usually used to realize the voltage reference. However, in the actual manufacturing process, process parameter deviation and circuit mismatch and other non-ideal factors cannot be avoided. These non-ideal factors will affect the output voltage precision of the band gap reference, and make it deviate from the design value. Therefore, how to provide a stable reference voltage circuit is a problem to be solved at present. SUMMARY
[0003] To achieve the above purpose, the utility model adopts the following technical scheme:
[0004] The utility model embodiment provides a band gap reference voltage circuit, include: operational amplifier OP, MOS tube M1, triode Q1, triode Q2, resistance R1, resistance R2, resistance R3, resistance R4, resistance R5, first stage temperature compensation module, second stage temperature compensation module.
[0005] The base and the collector of the triode Q1 and the triode Q2 are grounded. The emitter of the triode Q1 is connected to one end of the resistance R1. The positive input end of the operational amplifier OP is connected to the common end of the resistances R1 and R3. The first stage temperature compensation module is connected to Vref and one end of the resistance R3 respectively. The emitter of the triode Q2 is connected to one end of the resistance R2. The negative input end of the operational amplifier OP is connected to the common end of the resistances R2 and R4. The resistances R5 is connected to the resistance R4 and the drain of the MOS tube M1 respectively. The source of the MOS tube M1 is connected to the power supply. The gate of the MOS tube M1 is connected to the output end of the operational amplifier OP. The second stage temperature compensation module is connected to the negative input end and the output end of the operational amplifier OP respectively.
[0006] Further, the first stage temperature compensation module selects a resistance array controlled by a digital circuit. The voltage amplitude of each resistance node in the resistance array changes with temperature, and the corresponding temperature coefficient is different in different temperature ranges. Through the control of the external digital circuit, the appropriate temperature compensation resistance can be selected, so that the reference voltage VREF with the minimum temperature coefficient in the wide temperature range is output at the node, further reducing the noise and power consumption, and improving the precision of the output reference voltage.
[0007] Further, the second-stage temperature compensation module comprises MOS transistor M2, MOS transistor M3 and MOS transistor M4; the source of MOS transistor M2 and the source of MOS transistor M3 are both connected to a power supply; the gate of MOS transistor M2 is connected to the output terminal of operational amplifier OP; the drain of MOS transistor M3 is connected to the inverting input terminal of operational amplifier OP; the drain of MOS transistor M2 is connected to the gate of MOS transistor M3 and the source of MOS transistor M4 respectively; the gate and the drain of MOS transistor M4 are both connected to ground.
[0008] Further, the resistance value of resistor R3 is the same as that of resistor R4; the total resistance value of the first-stage temperature compensation module is the same as that of resistor R5.
[0009] The utility model embodiment further provides a kind of integrated circuit, and the integrated circuit uses the band gap reference voltage circuit described above.
[0010] The band gap reference voltage circuit provided by the utility model has the advantages of simple structure, easy implementation, small area, low power consumption, high precision of output reference voltage and good temperature drift characteristics. BRIEF DESCRIPTION OF DRAWINGS
[0011] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or prior art, the drawings needed to be used in the embodiment or prior art description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can be obtained according to these drawings without creative labor.
[0012] Figure 1 The utility model provides a kind of band gap reference voltage circuit's circuit schematic diagram for the embodiment of the utility model. DETAILED DESCRIPTION
[0013] The technical scheme in the embodiments of the utility model will be described clearly and completely by combining with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the utility model.
[0014] Figure 1The utility model discloses a band gap reference voltage circuit, including: OP, MOS tube M1, triode Q1, triode Q2, resistance R1, resistance R2, resistance R3, resistance R4, resistance R5, first stage temperature compensation module U1, second stage temperature compensation module U2, the base and the collector of triode Q1 and triode Q2 are all grounded, triode Q1's emitter connects resistance R1 one end, and the common end of resistance R1 and R3 is connected to the positive input end of OP, and the both ends of first stage temperature compensation module are connected with Vref and resistance R3 one end respectively, triode Q2's emitter connects resistance R2 one end, and the common end of resistance R2 and R4 is connected to the reverse input end of OP, and the both ends of resistance R5 are connected with resistance R4 and MOS tube M1's drain respectively, the source of MOS tube M1 is connected with power supply, and the gate of MOS tube M1 is connected with the output end of OP, and the both ends of second stage temperature compensation module are connected with the reverse input end and the output end of OP respectively.
[0015] Two triodes match two MOS tubes in traditional band gap reference voltage circuit, and the two MOS tubes are combined into one MOS tube M1 in the application compared with traditional circuit, so that the influence of MOS tube mismatch and temperature characteristic fluctuation can be effectively reduced, and the current matching precision can be improved by connecting resistance R3 and R4 with the same resistance value in series at the two ends of the two triode emitters. Figure 1
[0016] The first stage temperature compensation module U1 is controlled by a digital circuit on the basis of the traditional band gap reference voltage circuit, the first stage temperature compensation module U1 selects a resistance array controlled by a digital circuit, and the total resistance value of the resistance array is the same as the resistance value of the resistance R5. The voltage amplitudes of the resistance nodes in the resistance array are different, and the corresponding temperature coefficients are different in different temperature ranges. The appropriate temperature compensation resistance can be selected through the control of the external digital circuit, so that the reference voltage VREF with the minimum temperature coefficient in the wide temperature range is output at the node, the noise and power consumption are further reduced, and the precision of the output reference voltage is improved.
[0017] The second stage temperature compensation module U2 includes MOS tubes M2, M3 and M4, the source of the MOS tube M2 and the source of the MOS tube M3 are connected to the power supply, the gate of the MOS tube M2 is connected to the output end of the OP, the drain of the MOS tube M3 is connected to the reverse input end of the OP, the drain of the MOS tube M2 is connected to the gate of the MOS tube M3 and the source of the MOS tube M4, and the gate and the drain of the MOS tube M4 are grounded.
[0018] The second stage temperature compensation module U2 includes a sub-threshold self-bias circuit and an I NL generating circuit. The sub-threshold self-bias circuit is a PMOS tube M2 in the application. Figure 1 The INL The generating circuit is MOS transistor M3 and MOS transistor M4 in 1. The sub-threshold self-biasing circuit can keep the VGS-VTH of the generating INL current PMOS transistor in a specified sub-threshold range through a current limiting mechanism and dynamic feedback, so as to realize stable sub-threshold region working state control; the gate input voltage of M2 is the output voltage Amp_out of the operational amplifier, and the current limiting mechanism of MOS transistor M2 can limit the branch current in a certain range. MOS transistor M4 can stably control the gate input voltage of MOS transistor M3 in a certain branch current range, so that M3 realizes stable sub-threshold region working state, and M3 generates I NL Control in a preset range.
[0019] The second-stage temperature compensation module U2 is a curvature compensation circuit, and generates a sub-threshold compensation current I NL The compensation current is generated by the MOS transistor working in the sub-threshold region, the current value is realized in a precise current range through a suitable width-length ratio, the non-PTAP error caused by the base resistance is offset, and thus the temperature drift characteristic of the reference source is improved.
[0020] Optionally, the embodiment of the present application further provides an integrated circuit using the bandgap reference voltage circuit.
[0021] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.
Claims
1. A bandgap reference voltage circuit, characterized by, Comprise: operational amplifier OP, MOS tube M1, triode Q1, triode Q2, resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, first-stage temperature compensation module, second-stage temperature compensation module; wherein, the base and the collector of the triode Q1 and the triode Q2 are grounded; the emitter of the triode Q1 is connected to one end of the resistor R1, the positive input end of the operational amplifier OP is connected to the common end of the resistor R1 and R3, and the two ends of the first-stage temperature compensation module are respectively connected to Vref and one end of the resistor R3; the emitter of the triode Q2 is connected to one end of the resistor R2, the negative input end of the operational amplifier OP is connected to the common end of the resistor R2 and R4, and the two ends of the resistor R5 are respectively connected to the resistor R4 and the drain of the MOS tube M1; the source of the MOS tube M1 is connected to the power supply, and the gate of the MOS tube M1 is connected to the output end of the operational amplifier OP; the two ends of the second-stage temperature compensation module are respectively connected to the negative input end and the output end of the operational amplifier OP.
2. The circuit of claim 1, wherein, The first-stage temperature compensation module selects a resistance array controlled by a digital circuit; the voltage amplitude of each resistance node in the resistance array changes with temperature, and the corresponding temperature coefficient is different in different temperature ranges; by controlling the external digital circuit, the appropriate temperature compensation resistance can be selected, so that the reference voltage VREF with the minimum temperature coefficient in the wide temperature range is output at the node, further reducing noise and power consumption, and improving the precision of the output reference voltage.
3. The circuit of claim 1, wherein, The second-stage temperature compensation module comprises: MOS tube M2, MOS tube M3 and MOS tube M4; the source of the MOS tube M2 and the source of the MOS tube M3 are both connected to the power supply; the gate of the MOS tube M2 is connected to the output end of the operational amplifier OP; the drain of the MOS tube M3 is connected to the negative input end of the operational amplifier OP; the drain of the MOS tube M2 is respectively connected to the gate of the MOS tube M3 and the source of the MOS tube M4; the gate and the drain of the MOS tube M4 are both grounded.
4. The circuit of claim 1, wherein, The resistance value of the resistor R3 and the resistor R4 is the same; the total resistance value of the first-stage temperature compensation module and the resistance value of the resistor R5 are the same.
5. An integrated circuit, characterized by The integrated circuit uses the bandgap reference voltage circuit of any one of claims 1 to 4.