阅读说明：本技术 高压集成电路及其温度检测电路 (High-voltage integrated circuit and temperature detection circuit thereof ) 是由 吴飞权 刘杰 于 2020-04-30 设计创作，主要内容包括：本发明提供一种高压集成电路及其温度检测电路,包括基准电流生成模块、第一电流生成模块、第二电流生成模块以及减法模块,基准电流生成模块根据电源电压产生基准电流,第一电流生成模块生成第一电流,第二电流生成模块生成第二电流,减法模块根据第一电流和第二电流获取电流差值,并根据电流差值输出电压；本发明技术方案第一电流与第二电流的差值设定电压偏置,通过减法模块输出正温度系数电压,实现了温度检测,并且由于可以通过调整第一电流生成模块的电流镜像模块的比例关系进而调整第一电流,以及通过调整第二电流生成模块中电流镜像模块的比例关系进而调整第二电流,因此可以调整减法模块中偏置电压的大小,并且输出电压灵敏度高。(The invention provides a high-voltage integrated circuit and a temperature detection circuit thereof, which comprise a reference current generation module, a first current generation module, a second current generation module and a subtraction module, wherein the reference current generation module generates reference current according to power supply voltage, the first current generation module generates first current, the second current generation module generates second current, and the subtraction module acquires a current difference value according to the first current and the second current and outputs voltage according to the current difference value; according to the technical scheme, the voltage bias is set according to the difference value of the first current and the second current, the positive temperature coefficient voltage is output through the subtraction module, temperature detection is achieved, the first current can be adjusted by adjusting the proportional relation of the current mirror module of the first current generation module, the second current can be adjusted by adjusting the proportional relation of the current mirror module in the second current generation module, the magnitude of the bias voltage in the subtraction module can be adjusted, and the output voltage sensitivity is high.)

1. A temperature sensing circuit for a high voltage integrated circuit, comprising:

the input end of the reference current generation module is connected with the power voltage and used for generating reference current according to the power voltage;

the input end of the first current generation module is connected with a power supply voltage, and the control end of the first current generation module is connected with the first output end of the reference current generation module and is used for generating a first current according to the reference current;

a first input end of the second current generation module is connected with the power supply voltage, and a control end of the second current generation module is connected with a second output end of the reference current generation module and is used for generating a second current according to the reference current;

and the input end of the subtraction module is connected with the output end of the first current generation module, the first output end of the subtraction module is connected with the second input end of the second current generation module, and the second output end of the subtraction module outputs bias voltage, so that a current difference value is obtained according to the first current and the second current, and voltage is output according to the current difference value.

2. The temperature detection circuit of claim 1, wherein the reference current generation module comprises a first current mirror module, a second current mirror module, a first resistor, and a first switch module;

the input of first current mirror module does the input of reference current generation module, the first output of first current mirror module is connected the first input and the control end of second current mirror module, and constitute the second output of reference current generation module, the control end and the second output of first current mirror module connect the back jointly the second input of second current mirror module, and constitute the first output of reference current generation module, the first output of second current mirror module is connected the first input of first switch module, the second output of second current mirror module is connected the first end of first resistance, the second end of first resistance is connected the second input of first switch module, the earthing terminal ground connection of first switch module.

3. The temperature detecting circuit according to claim 2, wherein the first current mirror module comprises a MOS transistor P1 and a MOS transistor P2, a source of the MOS transistor P1 and a source of the MOS transistor P2 are connected in common to form an input terminal of the first current mirror module, a drain of the MOS transistor P1 forms a first output terminal of the first current mirror module, and a gate of the MOS transistor P1, a gate of the MOS transistor P2 and a drain of the MOS transistor P2 are connected in common to form a second output terminal of the first current mirror module;

the second current mirror module comprises a MOS transistor N1 and a MOS transistor N2, the drain electrode of the MOS transistor N1, the gate electrode of the MOS transistor N1 and the gate electrode of the MOS transistor N2 are connected in common to form a first input end of the second current mirror module, the drain electrode of the MOS transistor N2 forms a second input end of the second current mirror module, the source electrode of the MOS transistor N1 is a first output end of the second current mirror module, and the source electrode of the MOS transistor N2 is a second output end of the second current mirror module;

the first switch module comprises a transistor Q1 and a transistor Q2, a collector of the transistor Q1 is a first input terminal of the first switch module, a collector of the transistor Q2 is a second input terminal of the first switch module, and a base of the transistor Q1, an emitter of the transistor Q1, a base of the transistor Q2 and an emitter of the transistor Q2 are connected to the ground in common.

4. The temperature detecting circuit of claim 2, wherein the first current generating module is a MOS transistor P3, the source of the MOS transistor P3 is the input terminal of the first current generating module, the gate of the MOS transistor P3 is the control terminal of the first current generating module, and the drain of the MOS transistor P3 is the output terminal of the first current generating module.

5. The temperature detection circuit of claim 2, wherein the second current generation module comprises a third current mirror module, a second switch module, a second resistor, and a fourth current mirror module;

the input of third current mirror module does the first input of second electric current generation module, the control end and the first output of third current mirror module connect after connecing the input of second switch module, the control end of second switch module does the control end of second electric current generation module, the first end of second resistance is connected to the output of second switch module, and the second end ground connection of second resistance, the second output of third current mirror module is connected the second input and the control end of fourth current mirror module, the first input of fourth current mirror module does the second input of second electric current generation module, the earthing terminal ground connection of fourth current mirror module.

6. The temperature detecting circuit according to claim 5, wherein the third current mirror module comprises a MOS transistor P4 and a MOS transistor P5, a source of the MOS transistor P4 and a source of the MOS transistor P5 are connected in common to form an input terminal of the third current mirror module, a gate of the MOS transistor P4, a gate of the MOS transistor P5 and a drain of the MOS transistor P4 are connected in common to form a first output terminal of the third current mirror module, and a drain of the MOS transistor P5 is connected in common to form a second output terminal of the third current mirror module.

7. The temperature detecting circuit of claim 5, wherein the second switch module is a MOS transistor N3, the source of the MOS transistor N3 is the input terminal of the second switch module, the gate of the MOS transistor N3 is the control terminal of the second switch module, and the drain of the MOS transistor N3 is the output terminal of the second switch module.

8. The temperature sensing circuit of claim 5, wherein the fourth current mirror module comprises a MOS transistor N4 and a MOS transistor N5, a drain of the MOS transistor N5 is a first input terminal of the fourth current mirror module, a drain of the MOS transistor N4, a gate of the MOS transistor N4 and a gate of the MOS transistor N5 are commonly connected to form a second input terminal of the fourth current mirror module, and a source of the MOS transistor N4 and a source of the MOS transistor N5 are commonly connected to ground.

9. The temperature sensing circuit of claim 2, wherein the subtraction module comprises a resistor R3, wherein a first terminal of the resistor R3 is an input terminal of the subtraction module, a first output terminal of the subtraction module, and a second output terminal of the subtraction module, and wherein a second terminal of the resistor R3 is a ground terminal of the subtraction module.

10. A high voltage integrated circuit comprising the temperature detection circuit of any of claims 1 to 9.

Technical Field

The invention belongs to the technical field of integrated circuits, and particularly relates to a high-voltage integrated circuit and a temperature detection circuit thereof.

Background

The high-voltage integrated circuit technology is an indispensable technology in the modern power electronic technology field, and is increasingly applied to the driving field of power MOSFETs and IGBTs. The chip formed by packaging the high-voltage integrated circuit and the high-voltage power switch device is called an intelligent power driving chip. Because the high-voltage power switch device generally works under high voltage and large current, the switching loss is large, the generated heat is large, and if the heat cannot be rapidly dissipated from the chip, the internal temperature of the chip can be continuously increased. If the temperature monitoring measures are not taken, the normal operation of the chip is seriously influenced by further heat accumulation, and even the chip is directly failed. Therefore, the temperature detection circuit becomes an important component in the high voltage integrated circuit.

The temperature detection circuit converts the temperature change in the chip into an electric signal and feeds the electric signal back to the microcontroller at the front end so as to realize real-time monitoring, and further ensure that the intelligent power driving chip can work normally more reliably and stably.

Fig. 1 shows a conventional temperature detection circuit, which includes a transistor Q1, a transistor Q2, a resistor R1, a resistor R2, a MOS transistor P1, a MOS transistor P2, a MOS transistor P3, a MOS transistor N1, and a MOS transistor N2. The I1 branch and the I2 branch form a reference current generating circuit, and the reference current is proportional To the temperature, so the reference current is called PTAT (proportional To Absolute temperature) reference current. Since the difference in VBE between transistor Q1 and transistor Q2 is equal to the voltage drop across resistor R1, the difference in VBE between transistor Q1 and transistor Q2 is equal to the voltage drop across resistor R1

I1＝I2＝ΔVBE/R1＝VTlnN/R1……(Ⅰ)

Wherein VT is a thermal voltage, VT ═ kT/q; k is the Boltzvine constant (1.38X 10-23J/K); q is the charge amount of electrons (1.60X 10-19C); n is the ratio of the area of the emitter of transistor Q2 to the area of the emitter of transistor Q1; t is the thermodynamic temperature. MOS transistor P3 mirrors I1 or I2 current to obtain output current I3, and acts on resistor R2 to obtain output voltage Vtemp, so Vtemp can be expressed as Vtemp ═ I3 ═ R2 ═ WP3/WP2 ═ R2/R1 ═ kTlnN/q … … (ii)

In the formula, WP3 and WP2 are the gate widths of MOS transistor P3 and MOS transistor P2, respectively, and the gate lengths of MOS transistor P3 and MOS transistor P2 are equal. As can be seen from equation (ii), if the temperature characteristics of the resistor R1 and the resistor R2 are completely matched, the output voltage Vtemp is proportional to T. Therefore, the conventional temperature detection circuit is a linear detection system in which the output voltage is proportional to the temperature.

Disclosure of Invention

The invention aims to provide a high-voltage integrated circuit and a temperature detection circuit thereof, and aims to solve the problem that the circuit design of the temperature detection circuit is too complex to cause the chip volume to be too large in the prior art.

The present invention is achieved in such a way that, in a first aspect, there is provided a temperature detection circuit for a high voltage integrated circuit, including:

the input end of the reference current generation module is connected with the power voltage and used for generating reference current according to the power voltage;

the input end of the first current generation module is connected with a power supply voltage, and the control end of the first current generation module is connected with the first output end of the reference current generation module and is used for generating a first current according to the reference current;

a first input end of the second current generation module is connected with the power supply voltage, and a control end of the second current generation module is connected with a second output end of the reference current generation module and is used for generating a second current according to the reference current;

and the input end of the subtraction module is connected with the output end of the first current generation module, the first output end of the subtraction module is connected with the second input end of the second current generation module, and the second output end of the subtraction module outputs bias voltage, and the subtraction module is used for obtaining a current difference value according to the first current and the second current and outputting the bias voltage according to the current difference value.

The second aspect of the present invention provides a high voltage integrated circuit, which includes the temperature detection circuit.

The invention provides a high-voltage integrated circuit and a temperature detection circuit thereof, which comprise a reference current generation module, a first current generation module, a second current generation module and a subtraction module, wherein the reference current generation module generates reference current according to power supply voltage; according to the technical scheme, the voltage bias is set according to the difference value of the first current generated by the first current generation module and the second current generated by the second current module, the positive temperature coefficient voltage is output through the subtraction module, temperature detection is achieved, the first current can be adjusted by adjusting the proportional relation of the current mirror module of the first current generation module, the second current can be adjusted by adjusting the proportional relation of the current mirror module in the second current generation module, the magnitude of the bias voltage in the subtraction module can be adjusted, and the output voltage sensitivity is high.

Drawings

Fig. 1 is a circuit diagram of a temperature detection circuit provided in the prior art;

fig. 2 is a schematic structural diagram of a temperature detection circuit of a high voltage integrated circuit according to an embodiment of the present invention;

FIG. 3 is a circuit diagram of a temperature detection circuit of a high voltage integrated circuit according to an embodiment of the present invention;

fig. 4 is a simulation graph of the output voltage of the temperature detection circuit of the high voltage integrated circuit varying with temperature according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The following detailed description of implementations of the invention refers to the accompanying drawings in which:

fig. 1 shows a temperature detection circuit of a high voltage integrated circuit according to an embodiment of the present invention, and for convenience of description, only the relevant portions of the embodiment are shown, and the following details are described below:

an embodiment of the invention provides a temperature detection circuit for a high voltage integrated circuit, as shown in fig. 1,

a reference current generating module 101, an input end of which is connected to the power voltage, for generating a reference current according to the power voltage;

a first current generating module 102, an input end of which is connected to the power voltage, and a control end of which is connected to the first output end of the reference current generating module 101, for generating a first current according to the reference current;

a second current generating module 103, a first input end of which is connected to the power voltage, and a control end of which is connected to a second output end of the reference current generating module 101, for generating a second current according to the reference current;

the subtraction module 104 has an input end connected to the output end of the first current generation module 102, a first output end connected to the second input end of the second current generation module 103, and a second output end outputting a bias voltage, and is configured to obtain a current difference according to the first current and the second current and output a voltage according to the current difference.

The reference current generating module 101 may include a current mirror module, where the current mirror module generally includes two MOS transistors, and the reference current may be obtained by performing mirror copy on the power supply voltage.

The first current generating module 102 may be an MOS transistor, and another current mirror module is formed by the MOS transistor and an MOS transistor of a current mirror module in the reference current generating module 101, and the reference current is copied by the current mirror module to obtain the first current.

The second current generation module 103 may include a current mirror module and an MOS transistor, and another current mirror module is formed by the MOS transistor and the MOS transistor of the current mirror module in the reference current generation module 101, the reference current is copied by the current mirror module to obtain a third current, and the third current is copied by the current mirror module to obtain a second current.

The subtraction module 104 may include a first branch and a second branch of two branches, a first current passes through a combination of the two branches, a resistor is disposed on the first branch to form an output voltage, and a second current passes through the second branch, so that a current value on the first branch is a difference between the first current and the second current.

The invention provides a temperature detection circuit of a high-voltage integrated circuit, which comprises a reference current generation module 101, a first current generation module 102, a second current generation module 103 and a subtraction module 104, wherein the reference current generation module 101 generates reference current according to power supply voltage, the first current generation module 102 generates first current according to the reference current, the second current generation module 103 generates second current according to the reference current, and the subtraction module 104 acquires a current difference value according to the first current and the second current and outputs voltage according to the current difference value; according to the technical scheme of the invention, the voltage bias is set by the difference value of the first current generated by the first current generation module 102 and the second current generated by the second current module, the positive temperature coefficient voltage is output through the subtraction module 104, so that the temperature detection is realized, and the first current can be adjusted by adjusting the proportional relation of the current mirror module of the first current generation module 102, and the second current can be adjusted by adjusting the proportional relation of the current mirror module in the second current generation module 103, so that the magnitude of the bias voltage in the subtraction module 104 can be adjusted, and meanwhile, the sensitivity of the output voltage is high.

For the reference current generating module 101, the reference current generating module 101 includes a first current mirror module 111, a second current mirror module 112, a first resistor, and a first switch module 113;

the input end of the first current mirror module 111 is the input end of the reference current generating module 101, the first output end of the first current mirror module 111 is connected to the first input end and the control end of the second current mirror module 112 to form the second output end of the reference current generating module 101, the control end and the second output end of the first current mirror module 111 are connected to the second input end of the second current mirror module 112 after being connected in common, and form the first output end of the reference current generating module 101, the first output end of the second current mirror module 112 is connected to the first input end of the first switch module 113, the second output end of the second current mirror module 112 is connected to the first end of the first resistor, the second end of the first resistor is connected to the second input end of the first switch module 113, and the ground end of the first switch module 113 is grounded.

As an embodiment, as shown in fig. 3, the first current mirror module 111 includes a MOS transistor P1 and a MOS transistor P2, a source of the MOS transistor P1 and a source of the MOS transistor P2 are connected in common to form an input terminal of the first current mirror module 111, a drain of the MOS transistor P1 forms a first output terminal of the first current mirror module 111, and a gate of the MOS transistor P1, a gate of the MOS transistor P2, and a drain of the MOS transistor P2 are connected in common to form a second output terminal of the first current mirror module 111;

the second current mirror module 112 includes a MOS transistor N1 and a MOS transistor N2, a drain of the MOS transistor N1, a gate of the MOS transistor N1, and a gate of the MOS transistor N2 are commonly connected to form a first input terminal of the second current mirror module 112, a drain of the MOS transistor N2 forms a second input terminal of the second current mirror module 112, a source of the MOS transistor N1 is a first output terminal of the second current mirror module 112, and a source of the MOS transistor N2 is a second output terminal of the second current mirror module 112;

the first switching module 113 includes a transistor Q1 and a transistor Q2, a collector of the transistor Q1 is a first input terminal of the first switching module 113, a collector of the transistor Q2 is a second input terminal of the first switching module 113, and a base of the transistor Q1, an emitter of the transistor Q1, a base of the transistor Q2, and an emitter of the transistor Q2 are connected to ground.

For the first current generating module 102, as an embodiment, as shown in fig. 3, the first current generating module 102 is a MOS transistor P3, a source of the MOS transistor P3 is an input terminal of the first current generating module 102, a gate of the MOS transistor P3 is a control terminal of the first current generating module 102, and a drain of the MOS transistor P3 is an output terminal of the first current generating module 102.

For the second current generating module 103, the second current generating module 103 includes a third current mirror module 131, a second switch module 132, a second resistor, and a fourth current mirror module 133;

the input end of the third current mirror module 131 is the first input end of the second current generation module 103, the control end and the first output end of the third current mirror module 131 are connected to the input end of the second switch module 132 after being connected in common, the control end of the second switch module 132 is the control end of the second current generation module 103, the output end of the second switch module 132 is connected to the first end of the second resistor, the second end of the second resistor is grounded, the second output end of the third current mirror module 131 is connected to the second input end and the control end of the fourth current mirror module 133, the first input end of the fourth current mirror module 133 is the second input end of the second current generation module 103, and the ground end of the fourth current mirror module 133 is grounded.

As an embodiment, as shown in fig. 3, the third current mirror module 131 includes a MOS transistor P4 and a MOS transistor P5, a source of the MOS transistor P4 and a source of the MOS transistor P5 are commonly connected to form an input terminal of the third current mirror module 131, a gate of the MOS transistor P4, a gate of the MOS transistor P5 and a drain of the MOS transistor P4 are commonly connected to form a first output terminal of the third current mirror module 131, and a drain of the MOS transistor P5 forms a second output terminal of the third current mirror module 131.

As an embodiment, as shown in fig. 3, the second switch module 132 is a transistor N3, a source of a transistor N3 is an input terminal of the second switch module 132, a gate of a transistor N3 is a control terminal of the second switch module 132, and a drain of a transistor N3 is an output terminal of the second switch module 132.

As an embodiment, as shown in fig. 3, the fourth current mirror module 133 includes a MOS transistor N4 and a MOS transistor N5, a drain of the MOS transistor N5 is a first input terminal of the fourth current mirror module 133, a drain of the MOS transistor N4, a gate of the MOS transistor N4, and a gate of the MOS transistor N5 are commonly connected to form a second input terminal of the fourth current mirror module 133, and a source of the MOS transistor N4 and a source of the MOS transistor N5 are commonly connected to ground.

For the subtraction module 104, as an embodiment, as shown in fig. 3, the subtraction module 104 includes a resistor R3, a first terminal of the resistor R3 is an input terminal of the subtraction module 104, a first output terminal of the subtraction module 104, and a second terminal of the resistor R3 is a ground terminal of the subtraction module 104.

The working principle of the embodiment is as follows:

the high-sensitivity PTAT current (first current) output by the first current generation module 102 is obtained by amplifying the reference current I1 or the reference current I2. The expression of the reference current I1 or the reference current I2 is the same as the expression (I) in the background art: i1 ═ I2 ═ Δ VBE/R1 ═ VTlnN/R1, so the high-sensitivity PTAT current (first current) I6 is expressed as:

I6＝(WP3/WP2)*kTlnN/(qR1)……(Ⅲ)

in the formula, WP3 and WP2 are the gate width of the MOS transistor P3 and the gate width of the MOS transistor P2 respectively, the gate length of the MOS transistor P3 is equal to the gate length of the MOS transistor P2, and K is a Boltzval constant (1.38 multiplied by 10-23J/K); q is the charge amount of electrons (1.60X 10-19C); n is the ratio of the area of the emitter of transistor Q2 to the area of the emitter of transistor Q1; t is the thermodynamic temperature.

MOS pipe N1, MOS pipe N3, triode Q1 and resistor R2 form a current mirror structure. The gate width and the gate length of the MOS transistor N1 and the MOS transistor N3 are equal. If the source voltages of the MOS transistor N1 and the MOS transistor N3 are always equal, the current I3 in the second current generating module 103 completely replicates the current of the reference current I1, and has the same temperature coefficient as the reference current I1. Alternatively, if the current I3 flowing through the MOS transistor N3 is always equal to the reference current I1 flowing through the MOS transistor N1, the source voltages of the MOS transistor N1 and the MOS transistor N3 should also be equal, and I3 ═ I1 ═ VBE1|/R1, where VBE1 is the voltage between the base and the emitter of the transistor Q1, | VBE1| has a negative temperature coefficient, and the resistor R1 also has a negative temperature coefficient if a high-resistance polycrystalline resistor is used. The temperature detection circuit of the invention applies the current mirror structure between the two situations, so that the temperature coefficient of the current I3 obtained by mirroring is determined by the temperature coefficient of the reference current I1, the temperature coefficient of the | VBE1| of the triode Q1 and the temperature coefficient of the resistor R2, the whole circuit shows a positive temperature coefficient and has a small temperature coefficient, and the low-sensitivity PTAT current is obtained. According to the saturation current formula of the MOS transistor, the current flowing through the MOS transistor N1 and the current flowing through the MOS transistor N3 can be respectively expressed as:

I1＝(1/2)*(μnCOXWP1/LP1)*(VG1-|VBE1|-VTHN1)2……(Ⅳ)

I3＝(1/2)*(μnCOXWP3/LP3)*(VG1-I3*R2-VTHN3)2……(Ⅴ)

in the formula, μ N is the mobility of electrons, COX is the gate oxide capacitance per unit area, WP1/LP1, and WP3/LP3 are the width-to-length ratio of the MOS transistor N1 and the width-to-length ratio of the MOS transistor N3, VG1 is the gate voltage of the MOS transistor N1, VTHN1 and VTHN3 are the threshold voltages of the MOS transistor N1 and the MOS transistor N3, respectively. The sizes and the threshold voltages of the MOS transistor N1 and the MOS transistor N3 are equal, and the expression of the current I3 can be derived from the formulas (IV) and (V) and is shown as the formula (VI):

I3＝(|VBE1|/R2)+{R2(2AI1)1/2+1±[2R2(2AI1)1/2+1+2R2A|VBE1|]1/2}/(R22A)；

wherein A is mu nCOXWP1/LP 1. From formula (vi), the temperature coefficient of the current I3 is related to the temperature coefficients of VBE1, R2 and I1, and it can be seen that the current I3 is no longer simply linear with respect to temperature. MOS transistor P4 and MOS transistor P5 form a current mirror, so that current I3 is copied to current I4, MOS transistor N4 and MOS transistor N5 also form a current mirror, and then current I4 is copied to current I5. The current I5 is used as a low-sensitivity PTAT current and sent to a subtraction circuit to be subtracted from the high-sensitivity PTAT current I6, and finally an output voltage Vtemp is obtained on a resistor R3, so that Vtemp can be expressed as formula (iii):

Vtemp＝R3*[(WP3/WP2)*kTlnN/(qR1)-(WP5/WP4)*(WN5/WN4)*I3]

in the formula, WP5, WP4, WN5, and WN4 are gate widths of MOS transistor P5, MOS transistor P4, MOS transistor N5, and MOS transistor N4, respectively, gate lengths of MOS transistor P5 and MOS transistor P4 are equal, and gate lengths of MOS transistor N5 and MOS transistor N4 are also equal. Since the temperature coefficient of the current I3 is small and the temperature coefficient of Vtemp is mainly determined by the first term of the formula (iii), by designing the ratio of N, the ratio of the resistor R3 and the resistor R1, the ratio of the gate width of the MOS transistor P3 and the gate width of the MOS transistor P2, the ratio of the resistor R2, the gate width of the MOS transistor P5 and the gate width of the MOS transistor P4, and the ratio of the gate width of the MOS transistor N5 and the gate width of the MOS transistor N4, it is possible to obtain a high-sensitivity output voltage and a voltage bias at an arbitrary normal temperature.

Fig. 4 shows a simulation curve of the output voltage of the temperature detection circuit of the present invention as a function of temperature. As can be seen from fig. 4, Vtemp is proportional to temperature, and has a temperature coefficient of 20.3 mV/deg.c and an output voltage value of 894.7mV at room temperature.

Compared with the prior art, the temperature detection circuit has the advantages that the output voltage sensitivity of the temperature detection circuit is high, the voltage bias is set by subtracting the PTAT current with high sensitivity from the PTAT current with low sensitivity, and the positive temperature coefficient voltage is output on the resistor R3, so that the function of the temperature detection circuit is realized.

The second embodiment of the invention also provides a high-voltage integrated circuit which comprises the temperature detection circuit.

It should be noted that, since the high voltage integrated circuit provided in the second embodiment of the present invention includes the temperature detection circuit shown in fig. 3, reference may be made to the foregoing detailed description about fig. 3 for a specific operating principle of the integrated circuit provided in the second embodiment of the present invention, and details are not repeated here.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.