阅读说明：本技术 一种基于桥阻温度的扩散硅压力传感器压力补偿方法 (Pressure compensation method of diffused silicon pressure sensor based on bridge resistance temperature ) 是由 王士兴 李亚春 刘涛 于 2021-09-29 设计创作，主要内容包括：一种基于桥阻温度的扩散硅压力传感器压力补偿方法,通过给扩散硅压力传感器输入两种不同的恒流源激励,采集补偿温度范围内的扩散硅压力传感器的电阻桥毫伏值,即温度采样值和压力采样值的补偿数据,通过补偿数据对实测的压力采样值进行补偿；本发明不仅满足了对于高精度和宽温度补偿的要求,而且程序占用内存小、成本低。(A pressure compensation method of a diffused silicon pressure sensor based on bridge resistance temperature comprises the steps of inputting two different constant current source excitations to the diffused silicon pressure sensor, collecting a resistance bridge millivolt value of the diffused silicon pressure sensor within a compensation temperature range, namely compensation data of a temperature sampling value and a pressure sampling value, and compensating an actually measured pressure sampling value through the compensation data; the invention not only meets the requirements of high precision and wide temperature compensation, but also has small occupied memory of programs and low cost.)

1. A pressure compensation method of a diffused silicon pressure sensor based on bridge resistance temperature is characterized by comprising the following steps: the method comprises the steps of inputting two different constant current source excitations to the diffused silicon pressure sensor, collecting a resistance bridge millivolt value of the diffused silicon pressure sensor within a compensation temperature range, namely compensation data of a temperature sampling value and a pressure sampling value, and compensating the actually measured pressure sampling value through the compensation data.

2. A pressure compensation method of a diffused silicon pressure sensor based on bridge resistance temperature is characterized by comprising the following steps:

(1) providing two different constant current source excitations for the diffused silicon pressure sensor, and collecting a first temperature sampling value and a first pressure sampling value under all temperatures and pressures to be compensated to form compensation data;

(2) providing two different constant current source excitations for the diffused silicon pressure sensor, and collecting a second temperature sampling value Tsmp and a second pressure sampling value Psmp of the temperature and the pressure in any compensation range;

(3) searching and positioning the position of the second pressure sampling value Psmp according to the compensation data; searching and positioning the position of a second pressure sampling value Psmp according to a first pressure sampling value of each pressure point corresponding to the first temperature point, and recording a low pressure point value as P1 and a high pressure point value as P2;

(4) searching and positioning the position of the second temperature sampling value Tsmp according to the low pressure point value P1, the high pressure point value P2 and the compensation data; searching and positioning the ordinate of the second temperature sampling value Tsmp according to the first temperature sampling value of each temperature point corresponding to the first pressure point, recording the low temperature point value as T1, and recording the high temperature point value as T2;

(5) respectively determining 4 groups of data of the first pressure sampling value and the first temperature sampling value by taking the low-pressure point value P1, the high-pressure point value P2, the low-temperature point value T1 and the high-temperature point value T2 as coordinates, and obtaining a low-pressure point value P1 corresponding to the second temperature sampling value Tsmp, a third low-pressure point sampling value Psmp1 'and a third high-pressure point sampling value Psmp2' corresponding to the high-pressure point value P2 through linear calculation;

the point values at which the low-pressure point value P1 and the low-temperature point value T1 correspond are designated as Psmp1 and Tsmp1, the point values at which the low-pressure point value P1 and the high-temperature point value T2 correspond are designated as Psmp2 and Tsmp2, the point values at which the high-pressure point value P2 and the low-temperature point value T1 correspond are designated as Psmp3 and Tsmp3, the point values at which the high-pressure point value P2 and the high-temperature point value T2 correspond are designated as Psmp4 and Tsmp4, and Psmp1 'and Psmp2' are:

Psmp1'＝(Tsmp-Tsmp1)/(Tsmp2-Tsmp1)*(Psmp2-Psmp1)+Psmp1

Psmp2'＝(Tsmp-Tsmp3)/(Tsmp4-Tsmp3)*(Psmp4-Psmp3)+Psmp3

(6) linearly calculating the compensated pressure P by using the second pressure sampling value Psmp, the low pressure point value P1, the high pressure point value P2, the third low pressure point sampling value Psmp1 'and the third high pressure point sampling value Psmp 2';

P＝(Psmp-Psmp1')/(Psmp2'-Psmp1')*(P2-P1)+P1。

Technical Field

The invention belongs to the technical field of measurement, and particularly relates to a pressure compensation method of a diffused silicon pressure sensor based on bridge resistance temperature.

Background

With the development of semiconductor technology and integrated circuits, a semiconductor sensor manufactured based on the piezoresistive effect of semiconductor materials appears, wherein diffused silicon piezoresistive pressure sensors have the advantages of small size, excellent dynamic performance, low price and the like and are widely applied, but the resistance value of a bridge formed by using the diffused technology is easy to change along with the temperature, the piezoresistive coefficient of a piezoresistive element has a large negative temperature coefficient, and the resistance value and the resistance temperature coefficient are easy to be dispersed, so that the sensitivity drift and the zero point drift of the pressure sensor are caused, the temperature performance is poor, and therefore, temperature compensation is required.

Regarding the temperature compensation problem of the diffused silicon piezoresistive pressure sensor, most of the current situations are that a manufacturer carries out temperature compensation on the sensor through a semiconductor process such as laser resistance adjustment and the like in the production process, and the compensation mode has the defects of narrow compensation temperature range, low precision, high cost, poor universality and the like; in a few cases, temperature compensation is performed by an internally integrated temperature sensor or diode, but such a compensation method also has the disadvantages of low accuracy, high cost, and the like, and therefore, it is important to find a compensation method capable of ensuring wide temperature compensation and high accuracy.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a pressure compensation method of a diffused silicon pressure sensor based on bridge resistance temperature, which not only meets the requirements on high precision and wide temperature compensation, but also has small program occupied memory and low cost.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a pressure compensation method of a diffused silicon pressure sensor based on bridge resistance temperature is characterized in that two different constant current source excitations are input into the diffused silicon pressure sensor, the resistance bridge millivolt value of the diffused silicon pressure sensor in a compensation temperature range, namely the compensation data of a temperature sampling value and a pressure sampling value, is collected, and the actually measured pressure sampling value is compensated through the compensation data.

A pressure compensation method of a diffused silicon pressure sensor based on bridge resistance temperature comprises the following steps:

(1) providing two different constant current source excitations for the diffused silicon pressure sensor, and collecting a first temperature sampling value and a first pressure sampling value under all temperatures and pressures to be compensated to form compensation data;

(2) providing two different constant current source excitations for the diffused silicon pressure sensor, and collecting a second temperature sampling value Tsmp and a second pressure sampling value Psmp of the temperature and the pressure in any compensation range;

(3) searching and positioning the position of the second pressure sampling value Psmp according to the compensation data; searching and positioning the position of a second pressure sampling value Psmp according to a first pressure sampling value of each pressure point corresponding to the first temperature point, and recording a low pressure point value as P1 and a high pressure point value as P2;

(4) searching and positioning the position of the second temperature sampling value Tsmp according to the low pressure point value P1, the high pressure point value P2 and the compensation data; searching and positioning the ordinate of the second temperature sampling value Tsmp according to the first temperature sampling value of each temperature point corresponding to the first pressure point, recording the low temperature point value as T1, and recording the high temperature point value as T2;

(5) respectively determining 4 groups of data of the first pressure sampling value and the first temperature sampling value by taking the low-pressure point value P1, the high-pressure point value P2, the low-temperature point value T1 and the high-temperature point value T2 as coordinates, and obtaining a low-pressure point value P1 corresponding to the second temperature sampling value Tsmp, a third low-pressure point sampling value Psmp1 'and a third high-pressure point sampling value Psmp2' corresponding to the high-pressure point value P2 through linear calculation;

the point values at which the low-pressure point value P1 and the low-temperature point value T1 correspond are designated as Psmp1 and Tsmp1, the point values at which the low-pressure point value P1 and the high-temperature point value T2 correspond are designated as Psmp2 and Tsmp2, the point values at which the high-pressure point value P2 and the low-temperature point value T1 correspond are designated as Psmp3 and Tsmp3, the point values at which the high-pressure point value P2 and the high-temperature point value T2 correspond are designated as Psmp4 and Tsmp4, and Psmp1 'and Psmp2' are:

Psmp1'＝(Tsmp-Tsmp1)/(Tsmp2-Tsmp1)*(Psmp2-Psmp1)+Psmp1

Psmp2'＝(Tsmp-Tsmp3)/(Tsmp4-Tsmp3)*(Psmp4-Psmp3)+Psmp3

(6) linearly calculating the compensated pressure P by using the second pressure sampling value Psmp, the low pressure point value P1, the high pressure point value P2, the third low pressure point sampling value Psmp1 'and the third high pressure point sampling value Psmp 2';

P＝(Psmp-Psmp1')/(Psmp2'-Psmp1')*(P2-P1)+P1。

compared with the prior art, the invention has the following beneficial effects:

the invention can effectively improve the pressure value of the diffused silicon pressure sensor under the condition of temperature change, and has the advantages of wide temperature compensation and high precision.

The invention adopts a linear interpolation method, and has the advantages of memory saving and short traversal time;

the invention compensates the pressure value by using the resistance bridge of the diffused silicon pressure sensor, does not increase extra cost and has the advantage of low cost.

Drawings

FIG. 1 is a flow chart of an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the following examples and the accompanying drawings.

Referring to fig. 1, a pressure compensation method for a diffused silicon pressure sensor based on bridge resistance temperature includes the following steps:

(1) providing two different constant current source excitations for the diffused silicon pressure sensor, and collecting a first temperature sampling value and a first pressure sampling value under all temperatures and pressures to be compensated to form compensation data;

in the embodiment, first temperature sampling values and first pressure sampling values of all temperatures and pressures to be compensated are shown in table 1;

TABLE 1

(2) Providing two different constant current source excitations for the diffused silicon pressure sensor, and collecting a second temperature sampling value Tsmp and a second pressure sampling value Psmp of the temperature and the pressure in any compensation range;

second temperature sampled values Tsmp and second pressure sampled values Psmp of the diffused silicon pressure sensor of the present embodiment are shown in table 2;

TABLE 2

(3) Searching and positioning the position of the second pressure sampling value Psmp according to the compensation data; searching and positioning the position of a second pressure sampling value Psmp according to a first pressure sampling value of each pressure point corresponding to the first temperature point, and recording a low pressure point value as P1 and a high pressure point value as P2;

in the embodiment, the second pressure sampling value Psmp is 103.408, the low pressure point value P1 is 3.5, and the high pressure point value P2 is 4;

(4) searching and positioning the position of the second temperature sampling value Tsmp according to the low pressure point value P1, the high pressure point value P2 and the compensation data; searching and positioning the ordinate of the second temperature sampling value Tsmp according to the first temperature sampling value of each temperature point corresponding to the first pressure point, recording the low temperature point value as T1, and recording the high temperature point value as T2;

in this embodiment, the low pressure point value P1 and the high pressure point value P2 in table 1 are used as the basis to find and locate the position where the second temperature sampling value Tsmp is 883.911; taking the first temperature sampling values of the temperature points corresponding to 0MPa in table 1 as the basis, searching and positioning the second temperature sampling value Tsmp ═ 883.911 ordinate, the low temperature point value T1 ═ 20, and the high temperature point value T2 ═ 40;

(5) respectively determining 4 groups of data of the first pressure sampling value and the first temperature sampling value by taking the low-pressure point value P1, the high-pressure point value P2, the low-temperature point value T1 and the high-temperature point value T2 as coordinates, and obtaining a low-pressure point value P1 corresponding to the second temperature sampling value Tsmp, a third low-pressure point sampling value Psmp1 'and a third high-pressure point sampling value Psmp2' corresponding to the high-pressure point value P2 through linear calculation;

the point values at which the low-pressure point value P1 and the low-temperature point value T1 correspond are designated as Psmp1 and Tsmp1, the point values at which the low-pressure point value P1 and the high-temperature point value T2 correspond are designated as Psmp2 and Tsmp2, the point values at which the high-pressure point value P2 and the low-temperature point value T1 correspond are designated as Psmp3 and Tsmp3, the point values at which the high-pressure point value P2 and the high-temperature point value T2 correspond are designated as Psmp4 and Tsmp4, and Psmp1 'and Psmp2' are:

Psmp1'＝(Tsmp-Tsmp1)/(Tsmp2-Tsmp1)*(Psmp2-Psmp1)+Psmp1

Psmp2'＝(Tsmp-Tsmp3)/(Tsmp4-Tsmp3)*(Psmp4-Psmp3)+Psmp3

the corresponding point values of the low-pressure point value P1 and the low-temperature point value T1 are represented by Psmp 1-96.3617 and Tsmp 1-863.525, the corresponding points of the low-pressure point value P1 and the high-temperature point value T2 are represented by Psmp 2-95.6028 and Tsmp 2-905.151, the corresponding points of the high-pressure point value P2 and the low-temperature point value T1 are represented by Psmp 3-110.91 and Tsmp 3-863.77, and the corresponding points of the high-pressure point value P2 and the high-temperature point value T2 are represented by Psmp 4-110.039 and Tsmp 4-905.396, so that Psmp1 'and Psmp2' are:

Psmp1'＝95.99003481

Psmp2'＝110.4834347

(6) linearly calculating the compensated pressure P by using the second pressure sampling value Psmp, the low pressure point value P1, the high pressure point value P2, the third low pressure point sampling value Psmp1 'and the third high pressure point sampling value Psmp 2';

P＝(Psmp-Psmp1')/(Psmp2'-Psmp1')*(P2-P1)+P1，

the present embodiment calculates the compensated pressure P as 3.755823587.

If the diffused silicon pressure sensor is not compensated by the embodiment method, taking the first pressure sampling value of each pressure point at 20 ℃ in the table 1 as an example, the pressure value P' corresponding to the second pressure sampling value in the table 2 is calculated,

P'＝(103.408-96.3617)/(110.91-103.408)*(4-3.5)+3.5

P'＝3.9696。

the invention can be seen in using the compensation point data as the basis of compensation, not all points, and from this point, the whole method occupies little memory, and traverses the data of the complete sheet table quickly; next, as can be seen from table 2, the actual pressure value of the embodiment is 3.75, and comparing the compensated pressure value P with 3.7558 and the uncompensated pressure value P' with 3.9696, the error of the compensated pressure value is 0.155%, and the error of the uncompensated pressure value is 5.856%, and the superiority of the method of the present invention can be clearly seen from the errors of the compensated pressure value and the uncompensated pressure value; the invention does not use laser resistance adjustment and integrated sensor or diode mode to compensate temperature, thus reducing the development cost of the product.