A capacitor value adjusting device and method suitable for a capacitor detection chip

Abstract

The application discloses a capacitor value adjusting device and method suitable for a capacitor detection chip, and the method comprises the following steps: collecting a first initial capacitor value under touch sensing by using a main channel sensing surface PAD, obtaining a first actual capacitor value after analog-digital conversion, smoothing filtering and environment compensation; collecting a second initial capacitor value under touch sensing by using a temperature compensation PAD, obtaining a second actual capacitor value after analog-digital conversion, smoothing filtering and environment compensation; obtaining the first actual capacitor value and the second actual capacitor value, dynamically adjusting a temperature compensation coefficient according to the first actual capacitor value and the second actual capacitor value, and calculating a compensated capacitor value according to the temperature compensation coefficient and the second actual capacitor value. By dynamically adjusting the temperature compensation coefficient and combining the second actual capacitor value to calculate the compensated capacitor value, the application can avoid the problem that the detected capacitor value rises in an unfixed manner due to temperature change.

Description

Technical Field

[0001] This invention relates to the field of measurement and control technology, and in particular to a capacitance value adjustment device and method suitable for capacitance detection chips. Background Technology

[0002] Existing capacitance detection chips, commonly used in wearable devices, are characterized by their small size and low power consumption. However, due to differences in user groups (such as head size, wearing pressure levels), diverse environments (such as high temperature, low temperature, high humidity), and varied usage scenarios (such as changing or removing earcups), the capacitance detection chip often outputs abnormal signals. Abnormal signal output leads to abnormal responses from the main acquisition system, significantly impacting product performance. Current technology addresses this issue by using an environmental compensation module to eliminate interference from environmental factors. This involves reading the capacitance value of the entire surrounding environment and compensating the detection result with a preset value to ensure the acquired capacitance value equals the actual sensed capacitance value. However, after prolonged wear, the capacitance detection chip's measured capacitance value continues to rise slowly due to temperature changes. This prevents the corresponding wear / removal threshold from being triggered when the wearable device is removed, and because the rise is not constant, simply increasing the wear / removal threshold cannot solve the problem. Summary of the Invention

[0003] This invention provides a capacitance value adjustment device and method suitable for capacitance detection chips, in order to solve the technical problem that the capacitance value detected by existing capacitance detection chips increases in an irregular manner due to temperature changes during long-term use.

[0004] To address the aforementioned technical problems, this invention provides a capacitance value adjustment device suitable for capacitance detection chips, comprising: a temperature compensation PAD and a data processing module;

[0005] The temperature compensation PAD is positioned at a preset distance on one side of the main channel sensing surface PAD in the capacitance detection chip; and each surface of the temperature compensation PAD is recessed from the main channel sensing surface PAD by a preset value.

[0006] The main channel sensing surface PAD is used to collect the first initial capacitance value under touch sensing. After analog-to-digital conversion and environmental compensation, the first initial capacitance value is used to obtain the first actual capacitance value and is transmitted to the data processing module.

[0007] The temperature compensation PAD is used to collect a second initial capacitance value under touch sensing. After analog-to-digital conversion and environmental compensation, the second initial capacitance value is used to obtain a second actual capacitance value and then transmitted to the data processing module.

[0008] The data processing module is used to receive the first actual capacitance value and the second actual capacitance value, and dynamically adjust the temperature compensation coefficient according to the first actual capacitance value and the second actual capacitance value, and then calculate the compensated capacitance value according to the temperature compensation coefficient and the second actual capacitance value.

[0009] This invention provides a temperature compensation PAD on one side of the main channel sensing surface PAD. Compared to the main channel sensing surface PAD, each surface of the temperature compensation PAD is recessed by a preset value, making the second initial capacitance value detected by the temperature compensation PAD close to the first initial capacitance value. After processing, the two capacitance values ​​are dynamically adjusted in the data processing module by adjusting the temperature compensation coefficient, and then combined with the second actual capacitance value to calculate the compensated capacitance value. This avoids the problem of the detected capacitance value increasing in an unstable manner due to temperature changes.

[0010] Furthermore, the preset value is greater than or equal to 1 mm.

[0011] Compared to the main channel sensing surface PAD, the temperature compensation PAD of the present invention has each surface recessed by 1 mm or more to obtain a second initial capacitance value that is close to the first initial capacitance value detected by the main channel sensing surface PAD. This facilitates the second actual capacitance value corresponding to the second initial capacitance value to follow the first actual capacitance value after temperature compensation in subsequent processing, thereby offsetting the increase in capacitance value caused by temperature changes.

[0012] Furthermore, the capacitance value adjustment device suitable for the capacitance detection chip further includes: a capacitance-to-voltage module and an ADC module;

[0013] The capacitor-to-voltage module is used to convert the first initial capacitance value and the second initial capacitance value into a first voltage signal corresponding to the first initial capacitance value and a second voltage signal corresponding to the second initial capacitance value, respectively, and transmit them to the compensation and cancellation module.

[0014] The ADC module is used to convert the first voltage signal and the second voltage signal into a first digital signal corresponding to the first voltage signal and a second digital signal corresponding to the second voltage signal, respectively.

[0015] Furthermore, the capacitance value adjustment device suitable for the capacitance detection chip further includes: a first low-pass filter module;

[0016] The first low-pass filter module is used to smooth the first digital signal and the second digital signal according to a filtering algorithm.

[0017] Furthermore, the capacitance value adjustment device suitable for capacitance detection chips also includes: a compensation cancellation module;

[0018] The compensation and cancellation module is used to read the environmental capacitance value of the surrounding environment. After the environmental capacitance value is converted from analog to digital and smoothed and filtered, the first digital signal and the second digital signal after filtering are compensated according to the processed environmental capacitance value to obtain the first actual capacitance value corresponding to the first digital signal and the second actual capacitance value corresponding to the second digital signal, respectively.

[0019] This invention converts the first and second initial capacitance values ​​into corresponding voltage signals using a capacitor-to-voltage conversion module and a compensation and cancellation module. After analog-to-digital conversion and filtering, environmental compensation is performed to eliminate interference from environmental factors.

[0020] On the other hand, embodiments of the present invention also provide a method for adjusting the capacitance value of a capacitance detection chip, comprising:

[0021] The first initial capacitance value under touch sensing is collected using the main channel sensing surface PAD. After analog-to-digital conversion and environmental compensation, the first actual capacitance value is obtained.

[0022] A temperature-compensated PAD is used to collect a second initial capacitance value under touch sensing. After analog-to-digital conversion and environmental compensation, the second actual capacitance value is obtained.

[0023] The first actual capacitance value and the second actual capacitance value are obtained, and the temperature compensation coefficient is dynamically adjusted based on the first actual capacitance value and the second actual capacitance value. Then, the compensated capacitance value is calculated based on the temperature compensation coefficient and the second actual capacitance value.

[0024] This invention avoids the problem of the detected capacitance value increasing in an irregular manner due to temperature changes by processing two capacitance values, dynamically adjusting the temperature compensation coefficient, and then combining it with the second actual capacitance value to calculate the compensated capacitance value.

[0025] Furthermore, the step of dynamically adjusting the temperature compensation coefficient based on the first actual capacitance value and the second actual capacitance value specifically involves:

[0026] The temperature compensation coefficient is dynamically adjusted based on the change in the first actual capacitance value, the change in the second actual capacitance value, and the compensation value from the previous moment.

[0027] This invention combines the compensation value of the previous moment with the changes in the first and second actual capacitance values ​​to dynamically adjust the temperature compensation coefficient. This allows the second actual capacitance value to follow the changes in the first actual capacitance value after temperature compensation, while eliminating the effect of inconsistent capacitance value increases caused by temperature.

[0028] Furthermore, the step of dynamically adjusting the temperature compensation coefficient based on the change in the first actual capacitance value, the change in the second actual capacitance value, and the compensated capacitance value from the previous moment includes:

[0029] When the change in the first actual capacitance value is greater than a preset value, and the change in the second actual capacitance value is greater than the preset value, and the change in the first actual capacitance value is greater than the capacitance value after compensation at the previous moment, the temperature compensation coefficient is increased; when the change in the first actual capacitance value is greater than the preset value, and the change in the second actual capacitance value is greater than the preset value, and the change in the first actual capacitance value is less than the capacitance value after compensation at the previous moment, the temperature compensation coefficient is decreased; when the change in the first actual capacitance value is less than the preset value, and the change in the second actual capacitance value is less than the preset value, and the negative number of the change in the first actual capacitance value is greater than the negative number of the capacitance value after compensation at the previous moment, the temperature compensation coefficient is decreased; when the change in the first actual capacitance value is less than the preset value, and the change in the second actual capacitance value is less than the preset value, and the negative number of the change in the first actual capacitance value is less than the negative number of the capacitance value after compensation at the previous moment, the temperature compensation coefficient is decreased.

[0030] When the first actual capacitance value and the second actual capacitance value increase, the present invention increases and decreases the temperature compensation coefficient when the change in the first actual capacitance value is large and small, respectively, so that the compensated capacitance value follows the first actual capacitance value while eliminating the influence of temperature. In addition, when the first actual capacitance value and the second actual capacitance value decrease, the temperature compensation coefficient decreases and increases, respectively, when the change in the first actual capacitance value is large and small, so that the compensated capacitance value follows the first actual capacitance value while eliminating the influence of temperature.

[0031] Furthermore, the step of dynamically adjusting the temperature compensation coefficient based on the first actual capacitance value and the second actual capacitance value also includes:

[0032] Calculate the difference between the change in the first actual capacitance value and the compensation capacitance value at the previous moment; wherein, the compensation capacitance value at the previous moment is the compensation capacitance value calculated based on the second actual capacitance value at the previous moment and the temperature compensation coefficient at the previous moment.

[0033] Based on the difference, determine the gear corresponding to the difference, and adjust the temperature compensation coefficient according to the gear.

[0034] This invention calculates the difference between the change in the first actual capacitance value and the compensation value at the previous moment, and adjusts the temperature compensation coefficient accordingly based on the magnitude of the difference and the corresponding gear. This achieves dynamic adjustment of the temperature compensation coefficient as the first actual capacitance value changes, thus eliminating the temperature influence of the capacitance detection chip during long-term use.

[0035] Further, the calculation of the compensated capacitance value based on the temperature compensation coefficient and the second actual capacitance value specifically involves:

[0036] The compensated capacitance value is calculated using the temperature compensation formula based on the temperature compensation coefficient and the second actual capacitance value; wherein the temperature compensation formula is:

[0037] calculated_useful=useful2*coef*a;

[0038] Where calculated_useful is the compensated capacitance value, useful2 is the second actual capacitance value, coef is the temperature compensation coefficient, and a is a constant determined by the capacitance detection chip at the factory. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of one embodiment of the capacitance value adjustment device for a capacitance detection chip provided by the present invention;

[0040] Figure 2 This is a schematic diagram of another embodiment of the capacitance value adjustment device for a capacitance detection chip provided by the present invention;

[0041] Figure 3 This is a flowchart illustrating one embodiment of the capacitance value adjustment method for capacitance detection chips provided by the present invention.

[0042] The reference numerals for the accompanying drawings in the specification are as follows:

[0043] 1. Temperature compensation PAD; 2. Main channel sensing surface PAD. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] Example 1

[0046] The present invention provides a capacitance adjustment device suitable for capacitance detection chips. The capacitance adjustment device is disposed in the capacitance detection chip and includes a temperature compensation PAD and a data processing module.

[0047] Please refer to Figure 1 This is a schematic diagram of an embodiment of a capacitance value adjustment device for a capacitance detection chip provided by the present invention. In this embodiment, the temperature compensation PAD is disposed at a preset distance on one side of the main channel sensing surface PAD in the capacitance detection chip; wherein, each surface of the temperature compensation PAD is recessed inward by a preset value compared to the main channel sensing surface PAD.

[0048] In this embodiment, the temperature compensation PAD is disposed at a preset distance on one side of the main channel sensing surface PAD in the capacitance detection chip, specifically: the temperature compensation PAD is disposed at a preset distance on the back side of the main channel sensing surface PAD in the capacitance detection chip.

[0049] In this embodiment, the preset value is greater than or equal to 1 mm; furthermore, the preset value is preferably 1.05 mm.

[0050] Compared to the main channel sensing surface PAD, the temperature compensation PAD of this invention has each surface recessed by 1 mm or more to obtain a second initial capacitance value that is close to the first initial capacitance value detected by the main channel sensing surface PAD. Furthermore, the initial capacitance values ​​obtained from each angle are relatively consistent, which facilitates the second actual capacitance value corresponding to the second initial capacitance value to follow the first actual capacitance value after temperature compensation in subsequent processing, thereby offsetting the increase in capacitance value caused by temperature changes.

[0051] The main channel sensing surface PAD is used to collect the first initial capacitance value under touch sensing. After analog-to-digital conversion and environmental compensation, the first initial capacitance value is used to obtain the first actual capacitance value and is transmitted to the data processing module.

[0052] The temperature-compensated PAD is used to collect a second initial capacitance value under touch sensing. After analog-to-digital conversion and environmental compensation, the second initial capacitance value is used to obtain a second actual capacitance value and then transmitted to the data processing module.

[0053] In this embodiment, the first initial capacitance value and the second initial capacitance value can also be smoothed and filtered; or, the values ​​of the first initial capacitance value and the second initial capacitance value can be restricted and outlier filtered, specifically: the first initial capacitance value and the second initial capacitance value obtained within a preset time are averaged or the average value is calculated, and the maximum and minimum values ​​of the first initial capacitance value and the second initial capacitance value obtained within the preset time are removed.

[0054] Please refer to Figure 2 This is a schematic diagram of another embodiment of the capacitance adjustment device for a capacitance detection chip provided by the present invention. The capacitance adjustment device for a capacitance detection chip further includes: a capacitance-to-voltage module and an ADC module;

[0055] The capacitor-to-voltage module is used to convert the first initial capacitance value and the second initial capacitance value into a first voltage signal corresponding to the first initial capacitance value and a second voltage signal corresponding to the second initial capacitance value, respectively, and transmit them to the compensation and cancellation module.

[0056] The ADC module is used to convert the first voltage signal and the second voltage signal into a first digital signal corresponding to the first voltage signal and a second digital signal corresponding to the second voltage signal, respectively.

[0057] In this embodiment, a capacitor-to-voltage module is first used to convert the first initial capacitance value and the second initial capacitance value acquired by the main channel sensing surface PAD and the temperature compensation PAD into corresponding first voltage signal and second voltage signal; wherein, the first voltage signal and the second voltage signal are analog signals; after analog-to-digital conversion by the ADC module, the corresponding digital signals are obtained, which are used for subsequent filtering and environmental compensation processing.

[0058] Furthermore, the capacitance value adjustment device suitable for the capacitance detection chip further includes: a first low-pass filter module;

[0059] The first low-pass filter module is used to smooth the first digital signal and the second digital signal according to a filtering algorithm.

[0060] Furthermore, a compensation offset module;

[0061] The compensation and cancellation module is used to read the environmental capacitance value of the surrounding environment. After the environmental capacitance value is converted from analog to digital and smoothed and filtered, the first digital signal and the second digital signal after filtering are compensated according to the processed environmental capacitance value to obtain the first actual capacitance value corresponding to the first digital signal and the second actual capacitance value corresponding to the second digital signal, respectively.

[0062] In this embodiment, the ADC module converts the first and second voltage signals, which are analog signals, into corresponding digital signals. Then, the first low-pass filter module performs smoothing filtering according to a filtering algorithm, such as a low-pass filter algorithm or a digital filter algorithm. After filtering, the first and second digital signals can be amplified.

[0063] This invention converts the first and second initial capacitance values ​​into corresponding voltage signals using a capacitor-to-voltage conversion module and a compensation and cancellation module. After analog-to-digital conversion and filtering, environmental compensation is performed to eliminate interference from environmental factors.

[0064] In this embodiment, the capacitance value adjustment device for the capacitance detection chip further includes: a second low-pass filter module; wherein the second low-pass filter module is used to perform smooth filtering on the ambient capacitance value, so that the processed ambient capacitance value can perform environmental compensation on the processed first digital signal and the processed second digital signal.

[0065] The data processing module is used to receive the first actual capacitance value and the second actual capacitance value, and dynamically adjust the temperature compensation coefficient according to the first actual capacitance value and the second actual capacitance value, and then calculate the compensated capacitance value according to the temperature compensation coefficient and the second actual capacitance value.

[0066] In this embodiment, after calculating the compensated capacitance value, the capacitance value can also be output via the data output module.

[0067] Please refer to Figure 3 This is a flowchart illustrating an embodiment of the capacitance value adjustment method for a capacitance detection chip provided by the present invention, mainly including steps 1011, 1012, and 102, as detailed below:

[0068] In this embodiment, the capacitance value adjustment method for capacitance detection chips is applied to the capacitance value adjustment device for capacitance detection chips as described in the embodiments of the present invention.

[0069] Step 1011: Use the main channel sensing surface PAD to collect the first initial capacitance value under touch sensing. After analog-to-digital conversion and environmental compensation, the first actual capacitance value is obtained.

[0070] Step 1012: Use a temperature-compensated PAD to collect the second initial capacitance value under touch sensing. After analog-to-digital conversion and environmental compensation, the second initial capacitance value is used to obtain the second actual capacitance value.

[0071] In this embodiment, the temperature compensation PAD is disposed at a preset distance on one side of the main channel sensing surface PAD in the capacitance detection chip; wherein, each surface of the temperature compensation PAD is recessed by a preset value compared with the main channel sensing surface PAD, so that the second initial capacitance value detected by the temperature compensation PAD at the same time is similar to the first initial capacitance value detected by the main channel sensing surface PAD.

[0072] In this embodiment, the first initial capacitance value and the second initial capacitance value can also be smoothed and filtered; or, the values ​​of the first initial capacitance value and the second initial capacitance value can be restricted and outlier filtered, specifically: the first initial capacitance value and the second initial capacitance value obtained within a preset time are averaged or the average value is calculated, and the maximum and minimum values ​​of the first initial capacitance value and the second initial capacitance value obtained within the preset time are removed.

[0073] Obtain the first actual capacitance value and the second actual capacitance value, and dynamically adjust the temperature compensation coefficient based on the first actual capacitance value and the second actual capacitance value. Then, calculate the compensated capacitance value based on the temperature compensation coefficient and the second actual capacitance value. The expressions for the first actual capacitance value and the second actual capacitance value are as follows:

[0074] diff = useful – average;

[0075] Where diff is the first actual capacitance value or the second actual capacitance value, useful is the first digital signal after filtering or the second digital signal after filtering, and average is the environmental capacitance value after filtering.

[0076] useful()=(1-filter1)*raw()+(1)*useful(-1);

[0077] Wherein, useful() is the first digital signal or the second digital signal after filtering, filter1 is the filtering coefficient of the first low-pass filter module, raw() is the first initial capacitor value or the second initial capacitor value, and useful(-1) is the first digital signal or the second digital signal after filtering at the previous moment.

[0078] average(n)=(1-filter2)*useful(n)+(filter2)*average(n-1);

[0079] Where average(n) is the environmental capacitance value after filtering, filter2 is the filtering coefficient of the second low-pass filter module, and average(n-1) is the environmental capacitance value after filtering at the previous time or the trigger time.

[0080] Step 102: Obtain the first actual capacitance value and the second actual capacitance value, and dynamically adjust the temperature compensation coefficient according to the first actual capacitance value and the second actual capacitance value, and then calculate the compensated capacitance value according to the temperature compensation coefficient and the second actual capacitance value.

[0081] When a wearable device equipped with a capacitance detection chip is worn, the actual capacitance value will be greater than the trigger threshold, generating an interrupt trigger. When the wearable device is removed, the actual capacitance value drops rapidly below the threshold, generating another interrupt trigger. However, when the wearable device is used for a long time, the actual capacitance value will rise slowly and irregularly, causing the threshold to not be triggered when the device is removed. Furthermore, the irregular rise process means that simply raising the threshold cannot fundamentally solve this problem. In this embodiment, by dynamically adjusting the temperature compensation coefficient, it is possible to obtain a compensated capacitance value after eliminating the influence of temperature while following the first actual capacitance value.

[0082] Furthermore, the step of dynamically adjusting the temperature compensation coefficient based on the first actual capacitance value and the second actual capacitance value specifically involves:

[0083] The temperature compensation coefficient is dynamically adjusted based on the change in the first actual capacitance value, the change in the second actual capacitance value, and the compensation value from the previous moment.

[0084] This invention combines the compensation value of the previous moment with the changes in the first and second actual capacitance values ​​to dynamically adjust the temperature compensation coefficient. This allows the second actual capacitance value to follow the changes in the first actual capacitance value after temperature compensation, while eliminating the effect of inconsistent capacitance value increases caused by temperature.

[0085] Furthermore, the step of dynamically adjusting the temperature compensation coefficient based on the change in the first actual capacitance value, the change in the second actual capacitance value, and the compensated capacitance value from the previous moment includes:

[0086] When the change in the first actual capacitance value is greater than a preset value, and the change in the second actual capacitance value is greater than the preset value, and the change in the first actual capacitance value is greater than the capacitance value after compensation at the previous moment, the temperature compensation coefficient is increased; when the change in the first actual capacitance value is greater than the preset value, and the change in the second actual capacitance value is greater than the preset value, and the change in the first actual capacitance value is less than the capacitance value after compensation at the previous moment, the temperature compensation coefficient is decreased; when the change in the first actual capacitance value is less than the preset value, and the change in the second actual capacitance value is less than the preset value, and the negative number of the change in the first actual capacitance value is greater than the negative number of the capacitance value after compensation at the previous moment, the temperature compensation coefficient is decreased; when the change in the first actual capacitance value is less than the preset value, and the change in the second actual capacitance value is less than the preset value, and the negative number of the change in the first actual capacitance value is less than the negative number of the capacitance value after compensation at the previous moment, the temperature compensation coefficient is decreased.

[0087] In this embodiment, the preset value can be set to any constant, and the specific value is determined according to the actual capacitance detection chip. For example, the preset value can be set to 0, 3000, etc.

[0088] When the first actual capacitance value and the second actual capacitance value increase, the present invention increases and decreases the temperature compensation coefficient when the change in the first actual capacitance value is large and small, respectively, so that the compensated capacitance value follows the first actual capacitance value while eliminating the influence of temperature. In addition, when the first actual capacitance value and the second actual capacitance value decrease, the temperature compensation coefficient decreases and increases, respectively, when the change in the first actual capacitance value is large and small, so that the compensated capacitance value follows the first actual capacitance value while eliminating the influence of temperature.

[0089] Furthermore, the step of dynamically adjusting the temperature compensation coefficient based on the first actual capacitance value and the second actual capacitance value also includes:

[0090] Calculate the difference between the change in the first actual capacitance value and the compensation capacitance value at the previous moment; wherein, the compensation capacitance value at the previous moment is the compensation capacitance value calculated based on the second actual capacitance value at the previous moment and the temperature compensation coefficient at the previous moment.

[0091] Based on the difference, determine the gear corresponding to the difference, and adjust the temperature compensation coefficient according to the gear.

[0092] In this embodiment, the temperature compensation coefficient may include a first level, a second level, and a third level. When the difference exceeds the first value, for example, 400, the temperature compensation coefficient is set to the third level. When the difference exceeds the second value but is less than the first value, for example, greater than 200 but less than 400, the temperature compensation coefficient is set to the second level. When the difference is less than the second value, for example, less than 200, the temperature compensation coefficient is set to the first level. The first, second, and third values ​​can be set by the user according to the needs and the factory settings of the capacitance detection chip.

[0093] This invention calculates the difference between the change in the first actual capacitance value and the compensation value at the previous moment, and adjusts the temperature compensation coefficient accordingly based on the magnitude of the difference and the corresponding gear. This achieves dynamic adjustment of the temperature compensation coefficient as the first actual capacitance value changes, thus eliminating the temperature influence of the capacitance detection chip during long-term use.

[0094] Further, the calculation of the compensated capacitance value based on the temperature compensation coefficient and the second actual capacitance value specifically involves:

[0095] The compensated capacitance value is calculated using the temperature compensation formula based on the temperature compensation coefficient and the second actual capacitance value; wherein the temperature compensation formula is:

[0096] calculated_useful=useful2*coef*a;

[0097] Where calculated_useful is the compensated capacitance value, useful2 is the second actual capacitance value, coef is the temperature compensation coefficient, and a is a constant determined by the capacitance detection chip at the factory.

[0098] This invention provides a temperature compensation PAD on one side of the main channel sensing surface PAD. Compared to the main channel sensing surface PAD, each surface of the temperature compensation PAD is recessed by a preset value, making the second initial capacitance value detected by the temperature compensation PAD close to the first initial capacitance value. After processing, the two capacitance values ​​are dynamically adjusted in the data processing module by adjusting the temperature compensation coefficient, and then combined with the second actual capacitance value to calculate the compensated capacitance value. This avoids the problem of the detected capacitance value increasing in an unstable manner due to temperature changes.

[0099] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A capacitance value adjustment device suitable for capacitance detection chips, characterized in that, The capacitance adjustment device is located in the capacitance detection chip and includes: a temperature compensation PAD and a data processing module; The temperature compensation PAD is positioned at a preset distance on one side of the main channel sensing surface PAD in the capacitance detection chip; and each surface of the temperature compensation PAD is recessed from the main channel sensing surface PAD by a preset value. The main channel sensing surface PAD is used to collect the first initial capacitance value under touch sensing. After analog-to-digital conversion and environmental compensation, the first initial capacitance value is used to obtain the first actual capacitance value and is transmitted to the data processing module. The temperature compensation PAD is used to collect a second initial capacitance value under touch sensing. After analog-to-digital conversion and environmental compensation, the second initial capacitance value is used to obtain a second actual capacitance value and then transmitted to the data processing module. The data processing module is used to receive the first actual capacitance value and the second actual capacitance value, and dynamically adjust the temperature compensation coefficient according to the first actual capacitance value and the second actual capacitance value, and then calculate the compensated capacitance value according to the temperature compensation coefficient and the second actual capacitance value.

2. The capacitance value adjustment device for a capacitance detection chip as described in claim 1, characterized in that, The preset value is greater than or equal to 1 mm.

3. The capacitance value adjustment device for a capacitance detection chip as described in claim 1 or 2, characterized in that, Also includes: Capacitor-to-voltage converter module and ADC module; The capacitor-to-voltage module is used to convert the first initial capacitance value and the second initial capacitance value into a first voltage signal corresponding to the first initial capacitance value and a second voltage signal corresponding to the second initial capacitance value, respectively, and transmit them to the compensation and cancellation module. The ADC module is used to convert the first voltage signal and the second voltage signal into a first digital signal corresponding to the first voltage signal and a second digital signal corresponding to the second voltage signal, respectively.

4. The capacitance value adjustment device for a capacitance detection chip as described in claim 3, characterized in that, Also includes: First low-pass filter module; The first low-pass filter module is used to smooth the first digital signal and the second digital signal according to the filtering algorithm.

5. The capacitance value adjustment device for a capacitance detection chip as described in claim 4, characterized in that, Also includes: Compensation offset module; The compensation and cancellation module is used to read the environmental capacitance value of the surrounding environment. After the environmental capacitance value is converted from analog to digital and smoothed and filtered, the first digital signal and the second digital signal after filtering are compensated according to the processed environmental capacitance value to obtain the first actual capacitance value corresponding to the first digital signal and the second actual capacitance value corresponding to the second digital signal, respectively.

6. A method for adjusting the capacitance value of a capacitance detection chip, characterized in that, The capacitance adjustment device for a capacitance detection chip as described in any one of claims 1-5 includes: The first initial capacitance value under touch sensing is collected using the main channel sensing surface PAD. After analog-to-digital conversion and environmental compensation, the first actual capacitance value is obtained. A temperature-compensated PAD is used to collect a second initial capacitance value under touch sensing. After analog-to-digital conversion and environmental compensation, the second actual capacitance value is obtained. The first actual capacitance value and the second actual capacitance value are obtained, and the temperature compensation coefficient is dynamically adjusted based on the first actual capacitance value and the second actual capacitance value. Then, the compensated capacitance value is calculated based on the temperature compensation coefficient and the second actual capacitance value.

7. The capacitance value adjustment method for a capacitance detection chip as described in claim 6, characterized in that, The step of dynamically adjusting the temperature compensation coefficient based on the first actual capacitance value and the second actual capacitance value specifically involves: The temperature compensation coefficient is dynamically adjusted based on the change in the first actual capacitance value, the change in the second actual capacitance value, and the compensation value from the previous moment.

8. The capacitance value adjustment method for a capacitance detection chip as described in claim 7, characterized in that, The step of dynamically adjusting the temperature compensation coefficient based on the change in the first actual capacitance value, the change in the second actual capacitance value, and the compensated capacitance value from the previous moment includes: When the change in the first actual capacitance value is greater than a preset value, and the change in the second actual capacitance value is greater than the preset value, and the change in the first actual capacitance value is greater than the capacitance value after compensation at the previous moment, the temperature compensation coefficient is increased; when the change in the first actual capacitance value is greater than the preset value, and the change in the second actual capacitance value is greater than the preset value, and the change in the first actual capacitance value is less than the capacitance value after compensation at the previous moment, the temperature compensation coefficient is decreased; when the change in the first actual capacitance value is less than the preset value, and the change in the second actual capacitance value is less than the preset value, and the negative number of the change in the first actual capacitance value is greater than the negative number of the capacitance value after compensation at the previous moment, the temperature compensation coefficient is decreased; when the change in the first actual capacitance value is less than the preset value, and the change in the second actual capacitance value is less than the preset value, and the negative number of the change in the first actual capacitance value is less than the negative number of the capacitance value after compensation at the previous moment, the temperature compensation coefficient is decreased.

9. The capacitance value adjustment method for a capacitance detection chip as described in claim 6, characterized in that, The step of dynamically adjusting the temperature compensation coefficient based on the first actual capacitance value and the second actual capacitance value further includes: Calculate the difference between the change in the first actual capacitance value and the compensation capacitance value at the previous moment; wherein, the compensation capacitance value at the previous moment is the compensation capacitance value calculated based on the second actual capacitance value at the previous moment and the temperature compensation coefficient at the previous moment. Based on the difference, determine the gear corresponding to the difference, and adjust the temperature compensation coefficient according to the gear.

10. The capacitance value adjustment method for a capacitance detection chip as described in any one of claims 6-9, characterized in that, The calculation of the compensated capacitance value based on the temperature compensation coefficient and the second actual capacitance value is specifically as follows: The compensated capacitance value is calculated using the temperature compensation formula based on the temperature compensation coefficient and the second actual capacitance value; wherein the temperature compensation formula is: ； in, The compensated capacitance value, This is the second actual capacitance value. This is the temperature compensation coefficient. It is a constant and is determined by the capacitance detection chip at the factory.

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