Method and system for correcting temperature error curve of digital temperature sensor

Abstract

Provided in the present invention are a method and system for correcting a temperature error curve of a digital temperature sensor, the method comprising: using a digital temperature sensor to acquire an actual digital temperature output; and using a first-order delta-sigma ADC curve correction parameter table embedded in the digital temperature sensor to correct a temperature error curve of the actual temperature output. Using the first-order delta-sigma ADC curve correction parameter table embedded in the digital temperature sensor to correct the temperature error curve of the actual temperature output comprises: on the basis of the curve correction parameter table in the first-order delta-sigma ADC, selecting an ADC conversion period corresponding to a pre-determined interval in which a measured temperature is located, and correcting a temperature curve slope of the current temperature interval by means of the ADC conversion period; and then selecting a translation parameter of the current temperature interval on the basis of the curve correction parameter table in the first-order delta-sigma ADC, so as to translate an error into a preset range of 0, thus implementing temperature error curve correction for the digital temperature sensor.

Description

Temperature error curve correction method and system of digital temperature sensor TECHNICAL FIELD

[0001] The present application relates to the technical field of integrated circuits, in particular, to a temperature error curve correction method and system of digital temperature sensor, more particularly, to a digital temperature error curve correction method and system embedded in an analog-to-digital converter. BACKGROUND

[0002] In a temperature sensor designed and manufactured by an integrated circuit, the most widely used is to quantize the environmental temperature variable sensed by a semiconductor device through an analog-to-digital converter, and then output in digital form. Such a digital output integrated circuit chip sensor has the advantage of strong anti-interference. Generally, the Vbe of a transistor or the Vdio of a diode in a semiconductor device has a monotonic temperature characteristic, generally about -2mV / ℃. By using a specific analog-to-digital converter for quantization, and then calibrating the gain from voltage change to digital change, and then calibrating the temperature error at a certain (such as room temperature) or several environmental temperatures, a digital output temperature sensor can be obtained. Through the above method and a well-designed temperature sensor, the precision can generally reach + / -1℃ to + / -2℃ in the environmental temperature range of -50℃ to 150℃. The loss of such temperature precision mainly comes from the second-order term and higher-order non-idealities of the temperature curve of the transistor Vbe or diode Vdio, in addition to the non-linearity of the ADC, etc.

[0003] In such a digital integrated circuit chip temperature sensor technology, the selection and design of the transistor or diode semiconductor device that reflects the temperature characteristic, the structure and circuit design of the analog-to-digital converter, and the design of the calibration circuit are involved. Generally speaking, temperature is a physical quantity that changes slowly, that is, the frequency bandwidth of the input signal is relatively low, so delta-sigma ADC can be used for quantization, which has the advantages of high stability, not easy to be disturbed, and relatively low circuit cost. In addition, through the special design of the modulator of the delta-sigma ADC, the digital output value of the temperature can be directly obtained without physically realizing the reference voltage and delta Vbe, greatly reducing the error term introduced by the realization of the reference voltage and delta Vbe by analog circuit, improving the consistency of the chip temperature output, and further improving the precision.

[0004] Nowadays, more and more products pursue higher temperature precision sensor chips to achieve better product performance and performance, such as some wearable products hope to accurately detect the temperature of the human body, or some temperature sensors used on instruments, etc. Under these conditions, the integrated circuit chip temperature sensor with the accuracy of + / -1℃~+ / -2℃ in the general-50℃~150℃ ambient temperature range cannot meet the requirements.

[0005] Therefore, the present application provides a method and system for correcting the digital temperature error curve embedded in the analog-to-digital converter, which modifies the high-order term of the temperature curve to obtain higher temperature precision.

[0006] SUMMARY

[0007] In view of the defects in the prior art, the purpose of the present application is to provide a temperature error curve correction method and system for a digital temperature sensor.

[0008] According to the temperature error curve correction method for a digital temperature sensor provided by the present application, the method comprises the following steps:

[0009] Step S1: obtaining an actual digital temperature output by using a digital temperature sensor;

[0010] Step S2: correcting the temperature error curve of the actual temperature output by using the first-order delta-sigma ADC curve correction parameter table embedded in the digital temperature sensor;

[0011] The step of correcting the temperature error curve of the actual temperature output by using the first-order delta-sigma ADC curve correction parameter table embedded in the digital temperature sensor comprises the following steps: selecting the ADC conversion period corresponding to the interval in which the measured temperature is located according to the curve correction parameter table in the first-order delta-sigma ADC, and correcting the temperature curve slope of the current temperature interval through the ADC conversion period; and then selecting the translation parameter of the current temperature interval according to the curve correction parameter table in the first-order delta-sigma ADC, and translating the error to the preset range of 0, so as to realize the temperature error curve correction of the digital temperature sensor.

[0012] Preferably, the digital temperature sensor comprises:

[0013] The first voltage input two-alternative switching array is connected to one end of the first sampling capacitor array, and the other end of the first sampling capacitor array is connected to the non-inverting input end of the error operational amplifier, one end of the first integral holding switch, and one end of the first reset switch, respectively; the other end of the first integral holding switch is connected to one end of the first integral capacitor; the other end of the first integral capacitor, the other end of the first reset switch, and the first output end of the error operational amplifier are all connected to the positive input end of the single-bit quantization hysteresis comparator;

[0014] The second voltage input two-option switch array is connected with one end of the second sampling capacitor array, and the other end of the second sampling capacitor array is connected with the reverse input end of the error operational amplifier, one end of the second integral holding switch, and one end of the second reset switch; the other end of the second integral holding switch is connected with one end of the second integral capacitor; the other end of the second integral capacitor, the other end of the second reset switch, and the second output end of the error operational amplifier are all connected with the negative input end of the single-bit quantization hysteresis comparator.

[0015] Preferably, each two-option switch in the first voltage input two-option switch array includes 0 voltage or Vbe+ / Vber.

[0016] Vbe+ is a Vbe voltage formed by a high current density through a transistor;

[0017] Vber is a Vbe voltage formed by a medium current density through a transistor.

[0018] Preferably, each two-option switch in the second voltage input two-option switch array can select 0 voltage or Vbe- / Vber.

[0019] Vbe- represents a Vbe voltage formed by a low current density through a transistor;

[0020] Vber is a Vbe voltage formed by a medium current density through a transistor.

[0021] Preferably, the digital temperature sensor includes 2 phase operations per cycle; during the first phase and the second phase operations, the reset switch and the integral holding switch are alternately opened and closed; meanwhile, the selective connection of the voltage input two-option switch array to 0V, or Vbe+, or Vbe-, or Vber is implemented to realize that the integrator output is increased or decreased by kVber, or increased or decreased by 10k△Vbe per cycle; wherein k is a coefficient.

[0022] Preferably, the actual digital temperature output obtained by the digital temperature sensor includes:

[0023] The output starts from 0, if the output is less than or equal to 0, the next cycle is +10k△Vbe, if the output is greater than 0, the next cycle is -kVber, and a counter is accumulated by 1 at the same time; the operation is continuously performed, and a total of t cycles are operated to realize a first-order delta-sigma ADC.

[0024] The constraint is satisfied as follows:

[0025] (t-c)*10k△Vbe-c*kVber=Vres;

[0026] Wherein, t is the total number of cycles running, c is the counter cumulative value;

[0027] Convert the counter cumulative value c into Celsius cc;

[0028] Wherein, T0 represents the adjustment value.

[0029] According to the present application provides a kind of temperature error curve correction system of digital temperature sensor, comprising:

[0030] Utilize the first-order delta-sigma ADC curve correction parameter table embedded in digital temperature sensor to carry out temperature error curve correction to actual temperature output;

[0031] The first-order delta-sigma ADC curve correction parameter table embedded in digital temperature sensor is utilized to carry out temperature error curve correction to actual temperature output, comprising: according to the ADC conversion period corresponding to the interval of the temperature to be measured selected by the curve correction parameter table in first-order delta-sigma ADC, the temperature curve slope of current temperature interval is corrected by ADC conversion period;Again, according to the shift parameter of current temperature interval selected by the curve correction parameter table in first-order delta-sigma ADC, the error is shifted to the preset range of 0, to realize the temperature error curve correction of digital temperature sensor.

[0032] Preferably, the digital temperature sensor comprises:

[0033] The first voltage input two-way switch array is connected with the one end of the first sampling capacitor array, and the other end of the first sampling capacitor array is connected with the non-inverting input end of the error operational amplifier, the one end of the first integral holding switch and the one end of the first reset switch respectively;The other end of the first integral holding switch is connected with the one end of the first integral capacitor;The other end of the first integral capacitor, the other end of the first reset switch and the first output end of the error operational amplifier are all connected with the positive input end of the single-bit quantization hysteresis comparator;

[0034] The second voltage input two-way switch array is connected with the one end of the second sampling capacitor array, and the other end of the second sampling capacitor array is connected with the inverting input end of the error operational amplifier, the one end of the second integral holding switch and the one end of the second reset switch respectively;The other end of the second integral holding switch is connected with the one end of the second integral capacitor;The other end of the second integral capacitor, the other end of the second reset switch and the second output end of the error operational amplifier are all connected with the negative input end of the single-bit quantization hysteresis comparator.

[0035] Each two-way switch in the first voltage input two-way switch array comprises 0 voltage or Vbe+ / Vber;

[0036] Vbe+ is the Vbe voltage formed by the transistor with high current density;

[0037] Vber is the Vbe voltage formed by the transistor with medium current density;

[0038] The second voltage input two-way switch array can select 0 voltage or Vbe- / Vber;

[0039] Vbe- represents the Vbe voltage formed by the transistor with low current density;

[0040] Vber is the Vbe voltage formed by the transistor with medium current density.

[0041] Preferably, the digital temperature sensor includes 2 phase operations per cycle; the reset switch and the integral hold switch are alternately turned on and off in the first phase and the second phase; meanwhile, the selective connection of the voltage input two-way switch array to 0V, or Vbe+, or Vbe-, or Vber is realized, so that the integrator output is increased or decreased by kVber, or increased or decreased by 10k△Vbe in a cycle; wherein k is a coefficient.

[0042] Preferably, the actual digital temperature output obtained by the digital temperature sensor comprises:

[0043] The output starts from 0, if the output is less than or equal to 0, the next cycle is +10k△Vbe, if the output is greater than 0, the next cycle is -kVber, and the counter is accumulated by 1, and the operation is continuously performed, and a total of t cycles are operated, so that a first-order delta-sigma ADC is realized;

[0044] The constraint is satisfied as follows:

[0045] (t-c)*10k△Vbe-c*kVber=Vres;

[0046] Wherein t is the total number of cycles, and c is the counter accumulated value.

[0047] The counter accumulated value c is converted into Celsius cc;

[0048] Wherein T0 represents an adjustment value.

[0049] Compared with the prior art, the present application has the following beneficial effects:

[0050] 1. The present application embeds a curve correction parameter table in a first-order delta-sigma ADC, wherein the delta-sigma ADC is an oversampling mode ADC, and the first-order delta-sigma ADC requires as many as several thousand clock cycles for a single temperature conversion; before the conversion is completed (for example, at 96% of the conversion cycle number), the interval of the measured temperature is determined in advance, and then the conversion cycle number that the ADC actually needs to complete the temperature conversion is selected from the parameter table corresponding to the temperature interval, and different conversion cycle numbers correspond to different slopes of the temperature curve, so that by selecting different conversion cycle numbers, the slope of the temperature curve in the temperature interval is corrected, in other words, when the sensor chip works in different measured temperature intervals, the conversion cycle number of the ADC is slightly different (the difference is within 1%), which just corrects the slope of different temperature intervals. Then select another translation parameter in the interval to translate the error to near 0. By selecting different parameters for different temperature intervals, the temperature error in each temperature interval can be small and smooth.

[0051] 2. The present application has simple and effective circuit, the additional digital circuit for correcting the temperature error curve is small, and no additional time consumption and power consumption are required, and has complete predictability in principle, small area of layout, low cost, and can correct any error curve to achieve a full-temperature high-precision digital temperature output curve.

[0052] 3. Compared with analog error curve correction, digital correction has high stability and is not affected by integrated circuit manufacturing process fluctuations, and the design effect is completely predictable, thereby avoiding multiple design iterations, and additionally occupying small chip area and low cost; for the digital correction method of multiple term fitting, the present application does not require additional multipliers and adders, does not require additional calculation period and power consumption, and the corrected curve is smoother, the chip area is small, and the cost is low. BRIEF DESCRIPTION OF DRAWINGS

[0053] Other features, objects and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments, made with reference to the accompanying drawings:

[0054] Fig. 1 is a schematic diagram of a temperature error curve correction system of a digital temperature sensor.

[0055] Fig. 2 is a schematic diagram of a temperature error output curve without curve correction.

[0056] Wherein, I4-1~I4-10-first sampling capacitor array; I6-1~I6-10-second sampling capacitor array; I5-1~I5-10-first voltage input two alternative switch array; I7-1~I7-10-second voltage input two alternative switch array; I0-error operational amplifier; I2-first reset switch; I8-second reset switch; I1-first integration capacitor; I10-second integration capacitor; I3-first integration holding switch; I9-second integration holding switch; I11-single bit quantization hysteresis comparator. DETAILED DESCRIPTION

[0057] The application will be described in detail below with specific examples. The following examples will help those skilled in the art to further understand the application, but do not limit the application in any form. It should be pointed out that for those skilled in the art, without departing from the concept of the application, a number of changes and improvements can be made. These are within the scope of the application.

[0058] According to the temperature error curve correction method of the digital temperature sensor provided by the application, the method comprises the steps that:

[0059] Step S1: acquiring actual digital temperature output by using a digital temperature sensor;

[0060] Step S2: correcting the temperature error curve of the actual temperature output by using a first-order delta-sigma ADC curve correction parameter table embedded in the digital temperature sensor;

[0061] The step of correcting the temperature error curve of the actual temperature output by using the first-order delta-sigma ADC curve correction parameter table embedded in the digital temperature sensor comprises the steps that: selecting an ADC conversion period corresponding to a temperature interval in which the measured temperature is located according to the curve correction parameter table in the first-order delta-sigma ADC, and correcting the temperature curve slope of the current temperature interval through the ADC conversion period; and selecting a translation parameter of the current temperature interval according to the curve correction parameter table in the first-order delta-sigma ADC, and translating the error to a preset range of 0, so as to correct the temperature error curve of the digital temperature sensor.

[0062] The circuit simulation part of the application is a full-differential symmetric structure, which can eliminate the interference of power supply and ground fluctuation. The capacitor array provided by the embodiment is 10, but it is not limited to 10, and it depends on the temperature characteristics of Vbe+ and Vbe- of different processes, and the value may be other values near 10.

[0063] As shown in Fig. 1, the digital temperature sensor comprises: a first sampling capacitor array I4-1~I4-10, a second sampling capacitor array I6-1~I6-10; a first voltage input two-way switch array I5-1~I5-10 and a first voltage input two-way switch array I7-1~I7-10; an error operational amplifier I0; a first reset switch I2 and a second reset switch I8; a first integration capacitor I1 and a second integration capacitor I10; a first integration holding switch I3 and a second integration holding switch I9; and a single-bit quantization hysteresis comparator I11.

[0064] The first voltage input two-way switch array I5-1~I5-10 is connected with one end of the first sampling capacitor array I4-1~I4-10, and the other end of the first sampling capacitor array I4-1~I4-10 is connected with the non-inverting input end of the error operational amplifier I0, one end of the first integration holding switch I3 and one end of the first reset switch I2 respectively; the other end of the first integration holding switch I3 is connected with one end of the first integration capacitor I1; the other end of the first integration capacitor I1, the other end of the first reset switch I2 and the first output end of the error operational amplifier I0 are connected with the positive input end of the single-bit quantization hysteresis comparator I11.

[0065] The second voltage input two-way switch array I7-1~I7-10 is connected with one end of the second sampling capacitor array I6-1~I6-10, and the other end of the second sampling capacitor array I6-1~I6-10 is connected with the inverting input end of the error operational amplifier I0, one end of the second integration holding switch I9 and one end of the second reset switch I8 respectively; the other end of the second integration holding switch I9 is connected with one end of the second integration capacitor I10; the other end of the second integration capacitor I10, the other end of the second reset switch I8 and the second output end of the error operational amplifier I0 are connected with the negative input end of the single-bit quantization hysteresis comparator I11.

[0066] 0V in the circuit diagram represents 0 voltage, Vbe+ refers to the Vbe voltage formed by passing through a transistor at high current density (Vbe refers to the voltage difference between the base and the emitter), Vbe- refers to the Vbe voltage formed by passing through a transistor at low current density, and Vber refers to the Vbe voltage formed by passing through a transistor at medium current density;

[0067] When the comparator output is high, -kVber is needed, and Vber is selected; when the comparator output is low, +10k△Vbe is needed, and Vbe+ is selected. In this way, the output of the error operational amplifier is ensured to be within a range and not to be saturated, and this mechanism is the negative feedback mechanism of the delta-sigma ADC.

[0068] From the exponential characteristic of the triode, it can be known that △Vbe = (Vbe+) - (Vbe-) = KT / q*ln(Ic+ / Ic-), wherein K is the Boltzmann constant, T is the absolute temperature, q is the unit charge amount, Ic+ is the current density value of the triode at high current density, and Ic- is the current density value of the triode at low current density. It can be seen that △Vbe = (Vbe+) - (Vbe-) is proportional to the absolute temperature value, which is only theoretical, and the △Vbe of the triode actually manufactured by the process has high-order term deviation. The method provided by the present application will correct these high-order term deviations.

[0069] The circuit works in two phases in each cycle, phase 1 and phase 2. In phase 1 and phase 2, the reset switch and the integral hold switch are alternately opened and closed. In phase 1, I2 and I8 are closed, and I3 and I9 are opened; in phase 2, I2 and I8 are opened, and I3 and I9 are closed. At the same time, the voltage input two-select switch array is selectively connected to 0V, or Vbe+, or Vbe-, or Vber, so that the integrator output is increased or decreased by kVber (k is a coefficient, the value of k depends on the ratio of the integral capacitor and the sampling capacitor) or increased or decreased by 10k△Vbe in a cycle. For example, when in phase 1, one capacitor in the upper half of the capacitor array is connected to 0V, and the other 9 capacitors are connected to Vber; the lower half of the 10 capacitors are all connected to Vber. Then in phase 2, the upper half of the 10 capacitors are all connected to Vber, and the lower half of the 1 capacitor is connected to 0V, and the other 9 capacitors are connected to Vber. After one cycle, the output of the operational amplifier I0 is -kVber, where k is the gain coefficient, which depends on the ratio of the I1 and I10 capacitors to the capacitor array. Correspondingly, in phase 1, the upper half of the 10 capacitors are connected to Vber, and the lower half of the 9 capacitors are connected to Vber, and the other capacitor is connected to 0V. Then in phase 2, the upper half of the 9 capacitors are connected to Vber, and the 1 capacitor is connected to 0V, and the lower half of the 10 capacitors are all connected to Vber. This achieves an output of +kVber. Further, if in phase 1, the upper half of the 10 capacitors are all connected to Vbe+, and the lower half of the 10 capacitors are all connected to Vbe-, and then in phase 2, the upper half of the 10 capacitors are all connected to Vbe-, and the lower half of the 10 capacitors are all connected to Vbe+, this achieves an output of +10k△Vbe = +10k((Vbe+)-(Vbe-)). Correspondingly, if in phase 1, the upper half of the 10 capacitors are all connected to Vbe-, and the lower half of the 10 capacitors are all connected to Vbe+, and then in phase 2, the upper half of the 10 capacitors are all connected to Vbe+, and the lower half of the 10 capacitors are all connected to Vbe-, this achieves an output of -10k△Vbe = -10k((Vbe+)-(Vbe-)). Therefore, by controlling the array switch in different ways in each cycle, four kinds of increments can be achieved, which are -kVber, +kVber, +10k△Vbe and -10k△Vbe, respectively.

[0070] 3.1.4 The start of the output is from 0, if the output is less than or equal to 0, then the next cycle +10k△Vbe, if the output is greater than 0, then the next cycle -kVber, at the same time the counter is accumulated by 1, in this way the work is continuously carried out, a total of t cycles, so that a first-order delta-sigma ADC is realized. Then it meets the constraint: (t-c)*10k△Vbe-c*kVber=Vres, where t is the total number of cycles, c is the counter accumulation value, representing how many times Vber is reduced, and Vres is the residual amount, which is always controlled between + / -max(10k△Vbe, kVber) due to the control of the negative feedback. The above formula can be transformed as:

[0071] Because △Vbe increases with temperature, and the first-order term is proportional to temperature, and Vber is a negative temperature coefficient, through the appropriate design of the circuit, 10△Vbe+Vber can be made near 0 temperature coefficient, and the second term is less than 1. So as the temperature rises, the accumulated number of the counter is just a positive temperature coefficient that increases evenly, and the residual amount is less than 1, which can be truncated, so that c is obtained to realize digital temperature output, and through calibration and conversion to Celsius output, a digital temperature sensor is obtained.

[0072] If the second term is truncated by less than 1, and converted to Celsius cc by c, the formula is as follows, where T0 is the adjustment value needed to convert to Celsius. If the number of cycles t is increased, the slope of cc will increase, which will cause the output value of each temperature to increase, in order to approach 0 error, the value of T0 needs to be re-corrected:

[0073] The possible shape of the temperature error output curve without curve correction is shown in Figure 2:

[0074] Because in the actual device implementation, whether it is △Vbe or Vber is not only a first-order term of temperature, but also has higher-order terms, and other quantization errors of the ADC, etc., the output of the digital temperature sensor is similar to that shown in Figure 2. For high-precision applications, the curve needs to be corrected, such as the traditional method of directly adding a small analog component to Vber or △Vbe to correct, which faces the problem that the added component fluctuates with the process, and the shape that can be added is very limited, resulting in very limited final effect, which cannot be greatly improved.

[0075] The present application corrects the temperature error curve by a digital method embedded in the delta-sigma ADC, which is not affected by process fluctuation, and is designed completely predictable, and can achieve correction of any shape. Specifically, as in the above equation (2), the slope of the curve can be changed by changing the value of the period number t, and the curve can be shifted to the vicinity of 0 by changing the value of T0.

[0076] As in the above equation, only a pair of calibration parameters t and T0, the present application can achieve predictable curve correction of any shape by configuring different parameter lists in advance at different ambient temperatures. Specifically, for example, at the time when the temperature conversion has not run to t periods (such as at 96% t, and the specific number can be determined by design convenience, etc.), by reading the value of c, the temperature interval can be preliminarily judged, and on the basis of judging the ambient temperature, the digital circuit selects the t and T0 values of the ambient temperature interval from the correction table, such as ti and T0i, and then allows the ADC to continue conversion for ti-96% t periods. In this way, the entire conversion time is ti instead of t, thereby correcting the slope of the temperature curve, and moving the curve to the vicinity of the 0 axis with T0i. By configuring different ti and T0i for different temperature intervals, correction of any shape can be achieved. In other words, when the sensor chip works in different measured temperature intervals, the conversion period number of the ADC is slightly different (the difference is within one percent), which exactly corrects the slope in different temperature intervals. Of course, the traditional method can correct the curve by polynomial fitting, but this faces a large multiplier and adder, and increases the calculation by several periods, which not only increases the cost but also increases the power consumption, and still has high-order terms.

[0077] The present application not only can achieve correction of any curve, but also the connection at the boundary of the temperature interval can be completely smooth in principle, because

[0078] The present application also provides a temperature error curve correction system for a digital temperature sensor, which can be implemented by performing the flow steps of the temperature error curve correction method for the digital temperature sensor, that is, those skilled in the art can understand the temperature error curve correction method for the digital temperature sensor as the preferred embodiment of the temperature error curve correction system for the digital temperature sensor.

[0079] ​The specific embodiments of the present application are described above. It needs to be understood that the present application is not limited to the specific embodiments described above, and various changes or modifications can be made by those skilled in the art within the scope of the claims, which does not affect the essential content of the present application. The embodiments of the present application and the features in the embodiments can be combined with each other at will without conflict.

Claims

1. A method of correcting a temperature error curve of a digital temperature sensor, characterized by, The method comprises the steps of: Step S1: obtaining an actual digital temperature output by using a digital temperature sensor; Step S2: correcting a temperature error curve of the actual temperature output by using a first-order delta-sigma ADC curve correction parameter table embedded in the digital temperature sensor. The step of correcting the temperature error curve of the actual temperature output by using the first-order delta-sigma ADC curve correction parameter table embedded in the digital temperature sensor comprises the steps of: selecting an ADC conversion period corresponding to an interval in which a measured temperature is located according to the curve correction parameter table in the first-order delta-sigma ADC, and correcting a temperature curve slope of a current temperature interval by using the ADC conversion period; and selecting a translation parameter of the current temperature interval according to the curve correction parameter table in the first-order delta-sigma ADC, and translating an error to a preset range of 0, so as to correct the temperature error curve of the digital temperature sensor.

2. The temperature error curve correction method of a digital temperature sensor according to claim 1, characterized by, The digital temperature sensor comprises: A first voltage input two-selective switch array is connected to one end of a first sampling capacitor array, and the other end of the first sampling capacitor array is connected to a non-inverting input end of an error operational amplifier, one end of a first integral holding switch, and one end of a first reset switch; the other end of the first integral holding switch is connected to one end of a first integral capacitor; the other end of the first integral capacitor, the other end of the first reset switch, and a first output end of the error operational amplifier are all connected to a positive input end of a single-bit quantization hysteresis comparator; A second voltage input two-selective switch array is connected to one end of a second sampling capacitor array, and the other end of the second sampling capacitor array is connected to an inverting input end of the error operational amplifier, one end of a second integral holding switch, and one end of a second reset switch; the other end of the second integral holding switch is connected to one end of a second integral capacitor; the other end of the second integral capacitor, the other end of the second reset switch, and a second output end of the error operational amplifier are all connected to a negative input end of the single-bit quantization hysteresis comparator.

3. The temperature error curve correction method of a digital temperature sensor according to claim 2, characterized by, Each two-selective switch in the first voltage input two-selective switch array can select 0 voltage or Vbe+ / Vber; Vbe+ is a Vbe voltage formed by a high current density through a transistor; Vber is a Vbe voltage formed by a medium current density through a transistor.

4. The temperature error curve correction method of a digital temperature sensor according to claim 2, characterized by, Each two-selective switch in the second voltage input two-selective switch array can select 0 voltage or Vbe- / Vber; Vbe- is a Vbe voltage formed by a low current density through a transistor; Vber is a Vbe voltage formed by a medium current density through a transistor.

5. The temperature error curve correction method of a digital temperature sensor according to claim 2, wherein Each cycle of the digital temperature sensor comprises two phase operations; during the first phase and the second phase operations, the reset switch and the integral holding switch are alternately turned on and turned off; meanwhile, the selective connection of the voltage input two-selective switch array to 0 V, or Vbe+, or Vbe-, or Vber is realized, so that the output of the integrator is increased or decreased by kVber, or increased or decreased by 10k△Vbe in one cycle; wherein k is a coefficient.

6. The temperature error curve correction method of a digital temperature sensor according to claim 5, characterized by, The step of obtaining the actual digital temperature output by using the digital temperature sensor comprises the steps of: The output starts from 0, if the output is less than or equal to 0, the next cycle is +10k△Vbe, if the output is greater than 0, the next cycle is -kVber, at the same time, the counter is added by 1, and the work is continuously carried out, a total of t cycles, to realize the first-order delta-sigma ADC; The constraint is satisfied as follows: (t-c)*10k△Vbe-c*kVber=Vres; wherein t is the total number of cycles run, c is the counter cumulative value; convert the counter accumulated value c into degrees Celsius cc; Wherein, T0 represents an adjustment value.

7. A temperature error curve correction system for a digital temperature sensor, characterized by, It comprises: The actual temperature output is corrected by using a first-order delta-sigma ADC curve correction parameter table embedded in the digital temperature sensor; The actual temperature output is corrected by using a first-order delta-sigma ADC curve correction parameter table embedded in the digital temperature sensor, which comprises: selecting an ADC conversion period corresponding to the interval in which the measured temperature is located according to the curve correction parameter table in the first-order delta-sigma ADC, and correcting the temperature curve slope of the current temperature interval through the ADC conversion period; and selecting a translation parameter of the current temperature interval according to the curve correction parameter table in the first-order delta-sigma ADC, and translating the error to a preset range of 0, to realize the temperature error curve correction of the digital temperature sensor.

8. The temperature error curve correction method of a digital temperature sensor according to claim 7, characterized by, The digital temperature sensor comprises: A first voltage input two-way switch array is connected to one end of a first sampling capacitor array, and the other end of the first sampling capacitor array is connected to a non-inverting input end of an error operational amplifier, one end of a first integral holding switch, and one end of a first reset switch; the other end of the first integral holding switch is connected to one end of a first integral capacitor; the other end of the first integral capacitor, the other end of the first reset switch, and a first output end of the error operational amplifier are all connected to a positive input end of a single-bit quantization hysteresis comparator; A second voltage input two-way switch array is connected to one end of a second sampling capacitor array, and the other end of the second sampling capacitor array is connected to an inverting input end of the error operational amplifier, one end of a second integral holding switch, and one end of a second reset switch; the other end of the second integral holding switch is connected to one end of a second integral capacitor; the other end of the second integral capacitor, the other end of the second reset switch, and a second output end of the error operational amplifier are all connected to a negative input end of the single-bit quantization hysteresis comparator. Each two-way switch in the first voltage input two-way switch array can select 0 voltage or Vbe+ / Vber; Wherein, Vbe+ is a Vbe voltage formed by a high current density through a transistor; Vber is a Vbe voltage formed by a medium current density through a transistor; Each two-way switch in the second voltage input two-way switch array can select 0 voltage or Vbe- / Vber; Wherein, Vbe- is a Vbe voltage formed by a low current density through a transistor; Vber is a Vbe voltage formed by a medium current density through a transistor.

9. The temperature error curve correction system for a digital temperature sensor of claim 8, wherein, The digital temperature sensor includes 2 phase operations per cycle; during the first phase and the second phase, the reset switch and the integral hold switch are alternately opened and closed; meanwhile, the selective connection of the voltage input two-option switch array to 0V, Vbe+, Vbe- or Vber is realized, so that the integrator output is increased or decreased by kVber or 10k△Vbe in a cycle; wherein k is a coefficient.

10. The temperature error curve correction system for a digital temperature sensor of claim 9, wherein, The actual digital temperature output is obtained by using the digital temperature sensor, which comprises the following steps: The output starts from 0, if the output is less than or equal to 0, the next cycle is +10k△Vbe, if the output is greater than 0, the next cycle is -kVber, and the counter is accumulated by 1 at the same time, the operation is continuously carried out, and a total of t cycles are operated, so as to realize a first-order delta-sigma ADC; The constraint is satisfied as follows: (t-c)*10k△Vbe-c*kVber=Vres; wherein t is the total number of cycles run, and c is the counter cumulative value; convert the counter accumulated value c into degrees Celsius cc; Wherein, T0 represents an adjustment value.

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