CN107066015B - An all-cascode common source reference voltage source - Google Patents

Abstract

The invention discloses a fully-cascode reference voltage source,the circuit comprises a starting circuit, a reference current source circuit and a temperature compensation circuit which are connected in parallel between a power supply VDD and the ground; the starting circuit, the reference current source circuit and the temperature compensation circuit are connected in sequence; the output end of the starting circuit is connected with the reference current source circuit and used for providing starting current when the power supply is electrified so that the reference voltage source gets rid of a degenerated bias point; the output end of the reference current source circuit is connected with the temperature compensation circuit, and the power supply voltage rejection ratio and the voltage regulation rate are improved by utilizing the cascode current mirror and are used for generating reference current; the temperature compensation circuit is used for generating reference voltage with low temperature drift, a cascode current mirror is adopted, current is copied from the reference current source circuit, and the output voltage of the temperature compensation circuit is the output voltage V of the reference voltage source_ref. The invention relates to an ultra-low power consumption full cascode reference voltage source, which can better inhibit power supply noise.

Description

An all-cascode common source reference voltage source

technical field

The invention relates to the technical field of integrated circuits, in particular to a full cascode common source reference voltage source.

Background technique

Reference voltage sources are analog-to-digital converters (ADC), digital-to-analog converters (DAC), switching regulators (SPSM, LDO, DC-DC converters, etc.), oscillators, PLLs, temperature sensors, rechargeable battery protection chips, and It is an indispensable part of analog integrated circuits such as network communication circuits and digital-analog hybrid integrated circuits. It is used to generate a voltage with high precision and high stability, which does not change with changes in ambient temperature, power supply voltage, manufacturing process, noise and other factors, and provides a reference voltage for other circuit modules. Therefore, the reference voltage source is used in analog integrated circuits. Occupy a very important position, it directly affects the performance and precision of the circuit system.

With the increasing integration of integrated circuit systems, improving the performance and integration of reference sources has always been a research hotspot in this field. In response to the low power consumption requirements of electronic products in the market, the voltage reference source is a basic unit circuit, and its low power consumption design has become an inevitable trend. However, the traditional bandgap reference voltage source requires a large current and causes a large power consumption. To achieve low power consumption, the circuit structure is complex, and bipolar transistors need to be used in the design process, which occupies a large chip area and is incompatible with standard CMOS processes. The CMOS reference voltage source circuit proposed later used CMOS operating in the saturation region, which caused excessive power consumption. The reference voltage source based on the sub-threshold region proposed recently has better temperature drift and power supply suppression, but the power supply voltage regulation rate is poor, the chip area is too large, and the power consumption is too large.

Contents of the invention

The invention aims to solve the problems of poor power supply voltage adjustment rate, excessive chip area and excessive power consumption of the traditional reference voltage source circuit, and provides a full cascode common source reference voltage source.

In order to solve the above problems, the present invention is achieved through the following schemes:

A fully common-gate common-source reference voltage source, including a start-up circuit, a reference current source circuit, and a temperature compensation circuit connected in parallel between the power supply VDD and ground; the start-up circuit, the reference current source circuit, and the temperature compensation circuit are connected in sequence; the start-up circuit The output terminal is connected to the reference current source circuit, which is used to provide the starting current when the power supply is powered on, so that the reference voltage source can get rid of the degeneracy bias point; the output terminal of the reference current source circuit is connected to the temperature compensation circuit, and the cascode current mirror is used to Improve the power supply voltage rejection ratio and voltage adjustment rate to generate the reference current; the temperature compensation circuit is used to generate the reference voltage with low temperature drift, and the cascode current mirror is used to copy the current from the reference current source circuit, and the temperature compensation circuit outputs The voltage is the output voltage V _ref of the reference voltage source.

In the above solution, the start-up circuit is composed of MOS tube M1-MOS tube M11; the sources of MOS tube M1, MOS tube M5, MOS tube M8 and MOS tube M11 are connected to the power supply VDD; MOS tube M4, MOS tube M7 and MOS tube M10 The source and drain of the MOS transistor M6 and MOS transistor M9 are connected to the ground GND; the gate and drain of the MOS transistor M1 are connected to the source of the MOS transistor M2; the gate of the MOS transistor M2 After being connected to the drain, it is connected to the source of the MOS transistor M3; after the gate of the MOS transistor M3 is connected to the drain, it is connected to the gate of the MOS transistor M4; the gate of the MOS transistor M5 is connected to the gate of the MOS transistor M6 After being connected together, it is connected to the gate of MOS transistor M3; after the drain of MOS transistor M5 is connected to the drain of MOS transistor M6, it is connected to the gate of MOS transistor M7; the gate of MOS transistor M8 is connected to the gate of MOS transistor M9 After the grid is connected together, it is connected to the gate of the MOS transistor M7; after the drain of the MOS transistor M8 is connected to the drain of the MOS transistor M9, it is connected to the gate of the MOS transistor M10; the gate of the MOS transistor M11 is connected to the gate of the MOS transistor M11. The gate of the tube M10 is connected; the drain of the MOS tube M11 is used as the output terminal of the start-up circuit, and is connected with the input terminal of the reference current source circuit.

In the above scheme, the reference current source circuit is composed of MOS transistor M12-MOS transistor M19 and resistor R1; the sources of MOS transistor M12 and MOS transistor M13 are connected to the power supply VDD; the source of MOS transistor M18 is connected to ground GND; the MOS transistor M12 The drain of the MOS transistor M14 is connected to the source of the MOS transistor M14; the gate of the MOS transistor M13 is connected with the drain, and then connected to the gate of the MOS transistor M12; the drain of the MOS transistor M13 forms the first current branch of the reference current source circuit The output terminal of the circuit is connected to the input terminal of the first current branch of the temperature compensation circuit; the drain of the MOS transistor M13 is connected to the source of the MOS transistor M15; The gate of M14 is connected, and the drain of MOS transistor M15 forms the second current branch output end of the reference current source circuit, and is connected with the second current branch input end of the temperature compensation circuit; the drain electrode of MOS transistor M17 is connected with the MOS transistor The drain of M15 is connected; the source of MOS transistor M17 is connected to the drain of MOS transistor M19; the source of MOS transistor M19 is connected to ground GND through resistor R1; The gate of the tube M17 is connected; the drain of the MOS tube M16 is connected to the drain of the MOS tube M14; the gate of the MOS tube M18 is connected to the drain of the MOS tube M19; the drain of the MOS tube M18 Connect with the source of MOS tube M16.

In the above scheme, the temperature compensation circuit is composed of MOS tube M20-MOS tube M28, resistor R2 and capacitor C1; the sources of MOS tube M20 and MOS tube M21 are connected to power supply VDD; the source of MOS tube M26 is connected to ground GND; The gate of the tube M20 and the gate of the MOS tube M21 form the input end of the first current branch of the temperature compensation circuit, which is connected to the output end of the first current branch of the reference current source circuit; the drain of the MOS tube M20 is connected to the MOS tube The source of M22 is connected; the gate of MOS transistor M22 and the gate of MOS transistor M23 form the input end of the second current branch of the temperature compensation circuit, which is connected with the output end of the second current branch of the reference current source circuit; After the gate and drain of M24 are connected together, they are connected to the gate of MOS transistor M25; the drain of MOS transistor M24 is connected to the drain of MOS transistor M22; The gate of the tube M27 is connected; the drain of the MOS tube M26 is connected to the source of the MOS tube M24; the drain of the MOS tube M21 is connected to the source of the MOS tube M23; the drain of the MOS tube M23 is connected to the drain of the MOS tube M25 Connection; the source of the MOS transistor M25 is connected to the drain of the MOS transistor M27; the source of the MOS transistor M28 is connected to the ground GND through the resistor R2; one end of the capacitor C1 is grounded to GND, the other end of the capacitor C1 is connected to the gate of the MOS transistor M28 After being connected with the drain and the source of the MOS transistor M27, an output terminal of the temperature compensation circuit is formed, which is the output terminal of the reference voltage V _ref of the entire reference voltage source.

Compared with prior art, the present invention has following characteristics:

1. Ultra-low power consumption full cascode reference voltage source, better suppress power supply noise;

2. The start-up circuit does not use capacitors, reducing the layout area; using two inverters, the power-on time is slow, and it is better to get rid of the degeneracy bias point.

3. Using cascode type temperature compensation circuit structure can not only realize temperature compensation, but also enhance power supply rejection ratio.

Description of drawings

FIG. 1 is a schematic diagram of a full-cascode common-source reference voltage source.

Detailed ways

The present invention proposes an all-cascode common-source reference voltage source. Its specific circuit structure is shown in FIG. 1 , including a start-up circuit, a reference current source circuit and a temperature compensation circuit connected in parallel between the power supply VDD and the ground GND. The output end of the start-up circuit is connected with the reference current source circuit, and is used for providing a start-up current when the power supply is powered on, so that the reference voltage source gets rid of the degeneracy bias point. The output terminal of the reference current source circuit is connected with the temperature compensation circuit, and the cascode current mirror is used to improve the power supply voltage rejection ratio and the voltage adjustment rate, and is used to generate the reference current. The temperature compensation circuit is used to generate a reference voltage with low temperature drift. A cascode current mirror is used to copy the current from the reference current source circuit. The output voltage of the temperature compensation circuit is the output voltage V _ref of the reference voltage source.

The above start-up circuit includes MOS transistor M1-MOS transistor M11. Wherein, the sources of the MOS transistor M1 , the MOS transistor M5 , the MOS transistor M8 and the MOS transistor M11 are connected to the power supply VDD. The sources and drains of the MOS transistor M4, the MOS transistor M7 and the MOS transistor M10, and the sources of the MOS transistor M6 and the MOS transistor M9 are connected to the ground GND. The gate and the drain of the MOS transistor M1 are connected in common and then connected to the source of the MOS transistor M2. The gate and the drain of the MOS transistor M2 are connected together and then connected to the source of the MOS transistor M3. After the gate and the drain of the MOS transistor M3 are commonly connected, they are connected to the gate of the MOS transistor M4. After the gate of the MOS transistor M5 is connected to the gate of the MOS transistor M6, it is connected to the gate of the MOS transistor M3. After the drain of the MOS transistor M5 is connected to the drain of the MOS transistor M6, it is connected to the gate of the MOS transistor M7. After the gate of the MOS transistor M8 is connected to the gate of the MOS transistor M9, it is connected to the gate of the MOS transistor M7. After the drain of the MOS transistor M8 is connected to the drain of the MOS transistor M9, it is connected to the gate of the MOS transistor M10. The gate of the MOS transistor M11 is connected to the gate of the connected MOS transistor M10. The drain of the MOS transistor M11 is connected to the reference current source circuit as an output.

The start-up circuit is composed of MOS tube M1, MOS tube M2, and MOS tube M3 to form an active resistance, MOS tube M4, MOS tube M7 and MOS tube M10 to form a capacitor, and MOS tube M5, MOS tube M6, MOS tube M8 and MOS tube M9 to form The two inverters output the current through the drain of the MOS transistor M11, and are used to make the reference source get rid of the degeneracy bias point when the power supply is powered on. This start-up circuit does not require large capacitors and large resistors, and has no DC current in normal operation, reducing the area and reducing power consumption.

The above-mentioned reference current source circuit includes MOS transistor M12-MOS transistor M19 and resistor R1. Wherein, the sources of the MOS transistor M12 and the MOS transistor M13 are connected to the power supply VDD. The source of the MOS transistor M18 is connected to the ground GND. The drain of the MOS transistor M12 is connected to the source of the MOS transistor M14. After the gate and the drain of the MOS transistor M13 are commonly connected, they are connected to the gate of the MOS transistor M12. The drain of the MOS transistor M13 outputs the first current branch and is connected to the temperature compensation circuit. The drain of the MOS transistor M13 is connected to the source of the MOS transistor M15. After the gate and drain of the MOS transistor M15 are connected together, they are connected to the gate of the MOS transistor M14, and the drain of the MOS transistor M15 outputs the second current branch, and is connected to the temperature compensation circuit. The drain of the MOS transistor M17 is connected to the drain of the MOS transistor M15. The source of the MOS transistor M17 is connected to the drain of the MOS transistor M19. The source of the MOS transistor M19 is connected to the ground GND through the resistor R1. After the gate and the drain of the MOS transistor M16 are connected together, they are connected to the gate of the MOS transistor M17. The drain of the MOS transistor M16 is connected to the drain of the MOS transistor M14. After the gate and the drain of the MOS transistor M18 are commonly connected, they are connected to the gate of the MOS transistor M19. The drain of the MOS transistor M18 is connected to the source of the MOS transistor M16.

The reference current source circuit uses the gate-source voltage difference between the MOS transistor M18 and MOS transistor M19 working in the sub-threshold region to generate a bias voltage, and then converts the bias voltage into a bias current through the resistor R1, and then passes the cascode current mirror Duplicate the bias current into the temperature compensation circuit. A cascode current mirror is used to suppress power supply noise.

The above temperature compensation circuit includes MOS transistor M20-MOS transistor M28, resistor R2 and capacitor C1. Wherein, the sources of the MOS transistor M20 and the MOS transistor M21 are connected to the power supply VDD. The source of the MOS transistor M26 is connected to the ground GND. The capacitor C1 is connected in parallel between the output terminal of the reference voltage V _ref and the ground GND. The gates of the MOS transistor M20 and the MOS transistor M21 are connected to the first current branch of the reference current source circuit. The drain of the MOS transistor M20 is connected to the source of the MOS transistor M22. The gate of the MOS transistor M22 and the gate of the MOS transistor M23 are connected to the second current branch of the reference current source circuit. After the gate and the drain of the MOS transistor M24 are connected together, they are connected to the gate of the MOS transistor M25. The drain of the MOS transistor M24 is connected to the drain of the MOS transistor M22. After the gate and the drain of the MOS transistor M26 are connected together, they are connected to the gate of the MOS transistor M27. The drain of the MOS transistor M26 is connected to the source of the MOS transistor M24. The drain of the MOS transistor M21 is connected to the source of the MOS transistor M23. The drain of the MOS transistor M23 is connected to the drain of the MOS transistor M25. The source of the MOS transistor M25 is connected to the drain of the MOS transistor M27. After the gate and drain of the MOS transistor M28 are connected together, they are connected to the source of the MOS transistor M27, and the drain of the MOS transistor M28 is connected to the output terminal of the reference voltage V _ref . The source of the MOS transistor M28 is connected to the ground GND through the resistor R2.

The temperature compensation circuit uses the 1.8V and 3.3V MOS transistor grid-source voltage difference to generate a reference voltage with low temperature drift, and plays a role in suppressing power supply noise, and then the 3.3V MOS transistor M26 and 1.8V MOS transistor M27 grid-source The voltage difference produces a reference voltage V _ref with a low temperature drift.

Working principle of the present invention is:

In the start-up circuit, the gate and drain of MOS tube M1, MOS tube M2, and MOS tube M3 are connected to act as resistors, the source and drain of MOS tube M4, MOS tube M7 and MOS tube M10 are connected to the ground, which is equivalent to a capacitor, and the MOS tube M5, MOS tube M6 forms the first inverter, MOS transistor M8 and MOS transistor M9 form the second inverter, the source voltage of MOS transistor M5, MOS transistor M8, and MOS transistor M11 is VDD, and the power supply voltage VDD rises from zero to V _TH Finally, the MOS tube M1, MOS tube M2, and MOS tube M3 are gradually turned on to charge the MOS tube M4 as a capacitor. The tube M7 is charged. When the MOS tube M4 is charged, the upper plate of the MOS tube M4 is at a high level, the MOS tube M5 is cut off, the MOS tube M6 is turned on, the upper plate of the MOS tube M7 is at a low level, and the MOS tube M8 is turned on. The MOS tube M9 is turned off to charge the MOS tube M10. When the charging of the MOS tube M7 is completed, the upper plate of the MOS tube M7 is at a high level, the MOS tube M8 is turned off, and the MOS tube M9 is turned on. When the potential of the upper plate of the MOS tube M10 is low Level, so that the MOS tube M11 is turned on, and the current is injected into the reference current source circuit through eleven MOS tubes to get rid of the degeneracy bias point. When the MOS tube M10 is fully charged, the upper plate potential is high, so that the MOS tube When M11 is off, the start-up circuit is separated from the core circuit of the reference source. After the start-up is completed, the MOS transistor M1, MOS transistor M2, and MOS transistor M3 are in the cut-off state, with no quiescent current and no power consumption.

The core circuit of the present invention includes a reference current source circuit and a temperature compensation circuit.

In the reference current source circuit, the MOS transistors all work in the sub-threshold region, and the I-V characteristics of the MOS transistors working in the sub-threshold region can be expressed as formula (1):

When V _DS is greater than 4 times V _T , the influence of V _DS can be ignored, and the IV characteristics working in the subthreshold region can be expressed as (2) formula:

Furthermore, the gate-source voltage of the MOS transistor can be obtained as formula (3):

The voltage across the resistor R1 is equal to the difference between the gate-source voltage of the MOS transistor M18 operating in the sub-threshold region and the gate-source voltage of the MOS transistor _M19 , and the current ID of the reference current source circuit can be obtained as in formula (4):

in,

μ=μ ₀ (T ₀ /T) ^m (6)

V _T =k _B T/q (7)

By adjusting the ratio of K ₁₈ and K ₁₉ to adjust the relationship between ID and temperature _T , we can get

In the above formula, ID is the drain current of the MOS tube, _K =W/L is the width-to-length ratio of the MOS tube; W is the width of the MOS tube; L is the length of the MOS tube; I ₀ is the characteristic current; μ is the MOS tube The electron mobility of the tube; μ ₀ is the electron mobility at the reference temperature T ₀ ; T ₀ is the reference temperature; T is the absolute temperature; m is the temperature index; V _GS is the gate-source voltage of the MOS tube; V _DS is the voltage of the MOS tube Drain-source voltage; V _TH is the threshold voltage of the MOS tube; η is the slope factor of the sub-threshold region, which depends on the capacitance of the gate oxide layer and the loss layer, and is set as a constant; V _T is the thermal voltage; k _B is the Boltzmann constant; q is the electron charge.

In the temperature compensation circuit, a reference voltage with low temperature drift is obtained by using the gate-source voltage difference between the 1.8V MOS tube and the 3.3V MOS tube. The output reference voltage V _ref can be obtained from the circuit connection relationship, such as formula (8):

V _ref =V _GSM26 -V _GSM27 (8)

Using the IV characteristics of the working MOS transistor in the subthreshold region, the output voltage V _ref can be further obtained, as shown in formula (9):

The expression of the threshold voltage is (10) formula:

V _TH =V _TH0 -κT (10)

V _T has a positive temperature coefficient, and △V _TH has a negative temperature coefficient. By using V _T with a positive temperature coefficient and △V _TH with a negative temperature coefficient to adjust each other, an output reference voltage V _ref that has nothing to do with temperature can be obtained; the threshold voltage It can be further expressed as formula (11):

in,

The temperature coefficient of the threshold voltage is as in formula (13):

The process has almost no influence on the change of the temperature coefficient κ, so the temperature coefficient TC of the reference voltage V _ref hardly depends on the process change, and then the temperature coefficient TC of the reference voltage can be obtained as formula (14):

Let the temperature coefficient of the reference voltage be zero, then the width and length of the MOS tube can be determined such as formula (15):

It can be seen from (15) that by carefully adjusting k ₂₇ /k ₂₆ , temperature compensation can be better realized; use capacitor C1 to improve the power supply voltage rejection ratio of the bandgap reference voltage source.

In the above formula, t _OX,i represents the thickness of the gate oxide layer of the MOS transistor Mi; V _TH0 represents the threshold voltage value when the absolute temperature is 0K; κ=dV _TH /dT is the temperature coefficient TC of VTH; E _g is the band gap; ψ _B is the difference between the Fermi level potential energy and the intrinsic energy level potential energy; △V _TH is the difference between the threshold voltage; ε _Si is the relative dielectric constant of the silicon substrate; N _A is the substrate doping concentration; N _c is the conductivity Nv is the effective density of states of the valence band; _{n i} is the intrinsic carrier concentration.

The present invention relates to the field of integrated circuit design, in particular to a full-cascode common-source reference voltage source, which mainly solves the problems of large power consumption, large layout area, mismatch between devices and standard CMOS reference voltage sources, and poor performance in the prior art. The problem. It mainly consists of three parts: (1) Start-up circuit. In a preferred embodiment of the present invention, the above-mentioned start-up circuit includes PMOS transistors MOS transistor M1, MOS transistor M2, MOS transistor M3, MOS transistor M5, MOS transistor M8, MOS transistor M11 and NMOS tube MOS tube M4, MOS tube M6, MOS tube M7, MOS tube M9, MOS tube M10; used to provide current when the power supply is powered on, so that the reference voltage source can get rid of the degeneracy bias point, and does not need large-area capacitors and large resistance Value resistance, no DC current in normal operation, reduced area and reduced power consumption. (2) Reference current source circuit. In a preferred embodiment of the present invention, the reference current source circuit includes PMOS transistors MOS transistor M12, MOS transistor M13, MOS transistor M14, MOS transistor M15 and NMOS transistors MOS transistor M16, MOS transistor M17, MOS transistor M18, MOS transistor M19 and resistor R1; use cascode current mirror to suppress power supply noise, and use the working characteristics of MOS transistors working in the sub-threshold region to generate reference current. (3) Temperature compensation circuit. In a preferred embodiment of the present invention, the above temperature compensation circuit includes PMOS transistors MOS transistor M20, MOS transistor M21, MOS transistor M22, MOS transistor M23 and NMOS transistors MOS transistor M24, MOS transistor M25, MOS transistor M26, MOS tube M27, MOS tube M28, resistor R1, and capacitor C1; use cascode current mirror to suppress power supply noise, use 1.8V MOS tube and 3.3V MOS tube gate-source voltage difference, through mutual adjustment, get a Temperature Independent Reference Voltage. The extremely low power consumption is only on the order of nanowatts, and no bipolar transistors are used, which can not only eliminate the influence of temperature changes, reduce the layout area, but also be fully compatible with standard CMOS processes, reduce production costs, and have high Power supply voltage rejection ratio, low power supply voltage regulation rate, low temperature drift coefficient and other good performance characteristics. Under the SMIC 0.18-um CMOS process standard, the power supply voltage rejection ratio of this reference voltage source under the Cadence Specter emulator is -54.9dB at low frequencies, -76dB at high frequencies, and in the temperature range of -50—120 It has a temperature coefficient of 21.3ppm/℃, a power supply voltage regulation rate of 0.03% in the range of 1.3V-3.3V power supply voltage, and a power consumption of 108nW. These simulation results verify the effectiveness of the above measures.

The power consumption of the present invention is only nanowatts, and no bipolar transistors are used, which can not only eliminate the influence of temperature changes, reduce the layout area, but also be fully compatible with standard CMOS processes, reducing production costs, and at the same time It has the characteristics of high power supply voltage rejection ratio, extremely low power supply voltage adjustment rate, and low temperature drift coefficient.

Claims (3)

1. A full common-gate common-source reference voltage source, comprising a start-up circuit, a reference current source circuit and a temperature compensation circuit connected in parallel between the power supply VDD and the ground GND; the start-up circuit, the reference current source circuit and the temperature compensation circuit are sequentially connected ; The output terminal of the start-up circuit is connected with the reference current source circuit, which is used to provide a start-up current when the power supply is powered on, so that the reference voltage source gets rid of the degeneracy bias point; The output terminal of the reference current source circuit is connected with the temperature compensation circuit, and the cascode current mirror is used to improve the power supply voltage rejection ratio and the voltage adjustment rate for generating the reference current; The temperature compensation circuit is used to generate a reference voltage with low temperature drift, and a cascode current mirror is used to copy the current from the reference current source circuit, and the output voltage of the temperature compensation circuit is the output voltage V _ref of the reference voltage source; It is characterized by: The temperature compensation circuit is composed of MOS tube M20-MOS tube M28, resistor R2 and capacitor C1; The sources of the MOS transistor M20 and the MOS transistor M21 are connected to the power supply VDD; the source of the MOS transistor M26 is connected to the ground GND; the gate of the MOS transistor M20 and the gate of the MOS transistor M21 form the first current branch of the temperature compensation circuit The input end is connected to the output end of the first current branch of the reference current source circuit; the drain of the MOS transistor M20 is connected to the source of the MOS transistor M22; the gate of the MOS transistor M22 and the gate of the MOS transistor M23 form a temperature compensation circuit The input terminal of the second current branch circuit is connected with the output terminal of the second current branch circuit of the reference current source circuit; after the gate and drain of the MOS transistor M24 are connected together, they are connected with the gate electrode of the MOS transistor M25; the MOS transistor M24 The drain of the MOS transistor M22 is connected to the drain of the MOS transistor M22; the gate of the MOS transistor M26 is connected to the drain of the MOS transistor M27, and is connected to the gate of the MOS transistor M27; the drain of the MOS transistor M26 is connected to the source of the MOS transistor M24; The drain of the tube M21 is connected to the source of the MOS tube M23; the drain of the MOS tube M23 is connected to the drain of the MOS tube M25; the source of the MOS tube M25 is connected to the drain of the MOS tube M27; the source of the MOS tube M28 Connect to ground GND through resistor R2; one end of capacitor C1 is grounded to GND, and the other end of capacitor C1, the gate and drain of MOS transistor M28, and the source of MOS transistor M27 are connected to form the output end of the temperature compensation circuit. The output terminal of the temperature compensation circuit is the output terminal of the reference voltage V _ref of the entire reference voltage source. 2. A kind of all-cascode common-source reference voltage source according to claim 1, characterized in that: the start-up circuit is composed of MOS transistor M1-MOS transistor M11; The sources of MOS transistor M1, MOS transistor M5, MOS transistor M8 and MOS transistor M11 are connected to the power supply VDD; the source and drain of MOS transistor M4, MOS transistor M7 and MOS transistor M10, and the MOS transistor M6 and MOS transistor M9 The source is connected to the ground GND; the gate and drain of the MOS transistor M1 are connected to the source of the MOS transistor M2; the gate and the drain of the MOS transistor M2 are connected to the source of the MOS transistor M3; After the gate and drain of the tube M3 are connected together, they are connected to the gate of the MOS tube M4; after the gates of the MOS tube M5 and the gates of the MOS tube M6 are co-connected, they are connected to the gate of the MOS tube M3; the MOS tube M5 After the drain of the MOS transistor M6 is connected to the drain of the MOS transistor M6, it is connected to the gate of the MOS transistor M7; after the gate of the MOS transistor M8 is connected to the gate of the MOS transistor M9, it is connected to the gate of the MOS transistor M7; After the drain of the tube M8 is connected with the drain of the MOS tube M9, it is connected to the gate of the MOS tube M10; the gate of the MOS tube M11 is connected to the gate of the MOS tube M10; the drain of the MOS tube M11 is used as a starting circuit The output terminal of is connected with the input terminal of the reference current source circuit. 3. A kind of full cascode common source reference voltage source according to claim 1, is characterized in that: reference current source circuit is made up of MOS transistor M12-MOS transistor M19 and resistance R1; The sources of the MOS transistor M12 and the MOS transistor M13 are connected to the power supply VDD; the source of the MOS transistor M18 is connected to the ground GND; the drain of the MOS transistor M12 is connected to the source of the MOS transistor M14; the gate and the drain of the MOS transistor M13 After common connection, it is connected with the gate of MOS transistor M12; the drain of MOS transistor M13 forms the first current branch output end of the reference current source circuit, and is connected with the first current branch input end of the temperature compensation circuit; The drain of M13 is connected to the source of MOS transistor M15; after the gate and drain of MOS transistor M15 are connected together, they are connected to the gate of MOS transistor M14, and the drain of MOS transistor M15 forms the second current of the reference current source circuit The branch output terminal is connected to the second current branch input terminal of the temperature compensation circuit; the drain of the MOS transistor M17 is connected to the drain of the MOS transistor M15; the source of the MOS transistor M17 is connected to the drain of the MOS transistor M19; The source of the MOS transistor M19 is connected to the ground GND through the resistor R1; the gate and the drain of the MOS transistor M16 are connected to the gate of the MOS transistor M17; the drain of the MOS transistor M16 is connected to the drain of the MOS transistor M14 After the gate and drain of the MOS transistor M18 are connected together, they are connected to the gate of the MOS transistor M19; the drain of the MOS transistor M18 is connected to the source of the MOS transistor M16.