KR101924405B1 - Apparatus for measuring multi channel pressure distribution and Operating method thereof - Google Patents

Abstract

The present invention relates to a multichannel pressure distribution measuring apparatus and a method of operating the same. And a matrix sensor unit having a plurality of sensing electrodes formed on the substrate and configured to intersect with the driving electrodes to measure an amount of electrical change at an intersection of the driving electrode and the sensing electrode, A pressure distribution measuring apparatus for measuring a pressure distribution and a pressure on each intersection, comprising: a first driving power source for applying a first voltage to a selected one of a plurality of driving electrodes; a second driving power source for applying a second voltage to the non- A driving unit having a second driving power source for applying a driving voltage and a driving switch; A detection circuit connected to the selected detection electrode among the plurality of detection electrodes, a detection power source connected to the unselected detection electrode, and a detection unit having a detection switch; And a control unit for controlling the drive switch and the detected water position, wherein the control unit is provided on the main board, the drive unit is provided on the drive circuit board, and the main unit connected to the sensor unit, Wherein the board and the driving circuit board are laminated by a connector.

Description

[0001] The present invention relates to a multi-channel pressure distribution measuring apparatus and a pressure distribution measuring method using the same,

The present invention relates to a multichannel pressure distribution measuring apparatus and a method of operating the same.

The pressure distribution measuring device is a device that measures the distribution of applied pressure and the pressure on the individual lattice point by measuring the amount of physical change in the lattice point according to the pressure applied to the lattice point after lattice arrangement of the electrode to the plate- to be.

Pressure distribution measuring devices are used in manufacturing processes and medical devices. In case of using for fixing, it is used for the purpose of quality control by judging whether pressure distribution due to compression is uniform during the pressing and assembling process. In the case of medical devices, it is used to judge whether the foot or spine of the patient is healthy by measuring the uniformity of pressure distribution of the patient's foot.

The sensor of the pressure distribution measuring apparatus is usually arranged such that driving (detecting) electrodes are disposed horizontally (vertically) in the upper layer and detection (driving) electrodes are arranged vertically (horizontally) in the lower layer, And detects a change in the signal due to the pressure through the electrode.

If N detection electrodes and M driving electrodes are used, N × M detection operations must be performed in order to detect one pressure distribution shape.

However, as the market for smartphones and wearable appliances is rapidly expanding recently, there is a demand for manufacturers to improve the pressure distribution measuring resolution of pressure distribution measuring systems. For this purpose, the number of driving electrodes and detecting electrodes must be increased. For example, 2N driving electrodes and 2M detecting electrodes are required to double the resolution of a pressure distribution measuring system having N driving electrodes and M detecting electrodes.

In this case, the detection operation is 4 × N × M, which is four times as long as the conventional method. In addition, the increase of the driving electrode and the detecting electrode inevitably leads to an increase in the number of components, which again causes an increase in the size of the control board of the pressure distribution measuring system.

Therefore, in order to implement a multi-channel pressure distribution measurement system practically, it is necessary to improve the detection speed and to reduce the size of the control board.

The pressure distribution measurement system should also provide physical pressure, such as kgf / cm ² or PSI. On the other hand, the control board of the pressure distribution measurement system outputs only the digital value corresponding to the pressure, so a method of converting the digital value into the physical pressure amount is needed.

Also, in the conventional method, a multichannel pressure distribution measuring apparatus is constructed by combining a plurality of sensors and a plurality of control circuits in order to solve the measurement speed problem, but this increases the manufacturing cost. In addition, when a plurality of sensors are combined, there is a problem that the accuracy of the measurement is degraded due to the presence of a non-sensing region between the sensor and the sensor. In addition, when all the components are arranged on one board while maintaining the measurement speed, there is a problem that the size of the control board becomes very large and practical commercialization is difficult.

Korean Patent No. 1419139 Japanese Patent No. 5110878 Korean Patent No. 1009647 Japanese Patent No. 4993123

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a multi-channel pressure distribution measuring apparatus, Channel pressure distribution measuring apparatus and a method of operating the same by providing a method of converting a digital output of a control circuit of a pressure distribution measuring system into an actual pressure physical quantity by using a structure It has its purpose.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are not intended to limit the invention to the precise form disclosed. It can be understood.

SUMMARY OF THE INVENTION A first object of the present invention is to provide a liquid crystal display comprising a plurality of driving electrodes formed on a substrate and a matrix sensor unit having a plurality of detecting electrodes crossing the driving electrodes, A first driving power source for applying a first voltage to a selected one of the plurality of driving electrodes and a second driving power source for applying a second voltage to the selected driving electrode, A second driving power source for applying a second voltage, and a driving unit having a driving switch; A detection circuit connected to the selected detection electrode among the plurality of detection electrodes, a detection power source connected to the unselected detection electrode, and a detection unit having a detection switch; And a control unit for controlling the drive switch and the detection switch.

Further, the detecting unit and the control unit are provided on a main board, the driving unit is provided on the driving circuit board, and the main board and the driving circuit board connected to the sensor unit are laminated by a connector .

A second object of the present invention is to provide a pressure distribution measurement method using a pressure distribution measuring apparatus according to the first aspect, wherein an index q for selecting a detection electrode in Q detection electrodes is set to 1, A first step of applying a first voltage to the electrode by a first driving power source; a second step of detecting a measurement value S_q of the q-th detection electrode; A third step of setting the value of the pressure application judgment variable T_q to TRUE if S_q is equal to or greater than a preset value TH_q and setting T_q to FALSE when the value of S_q is smaller than the preset value TH_q; the second and third steps are repeated until q becomes equal to Q. If the same is true, it is determined that all the detection electrodes have been measured, and the value p for selecting the drive electrodes in the P drive electrodes is set to 1 A fourth step of setting a value q for selecting detection electrodes in Q detection electrodes to 1; (P, q) f of the node which is the intersection of the p-th driving electrode and the q-th detecting electrode when T_q is TRUE, and if it is FALSE, it is determined that there is no pressure, A fifth step of setting a detection value at an intersection of the electrodes to 0; if p and P are not the same, repeating the fifth step by adding 1 to p, and adding q to q when q and Q are not the same, and repeating the fifth step; And a seventh step of terminating the scan when p and P are the same, and q and Q are the same, and the seventh step is a method of operating the multi-channel pressure distribution measuring apparatus.

In the first object of the present invention, the plurality of detection electrodes included in the matrix sensor unit are grouped into k measurement groups, each of the L measurement groups grouped includes k operational amplifiers connected to k detection electrodes, and a multichannel ADC connected to outputs of the k arithmetic aids and receiving detection values detected from the k detection electrodes.

The multi-channel ADC of each of the L measurement groups is connected to the control unit. The multi-channel ADC receives a detection value detected at each of the k detection electrodes and outputs a sum of the detection values to the control unit To the mobile station.

The negative input of each of the operational amplifiers may be connected to the detection electrode and connected to the output through a feedback impedance, and the positive input may be connected to the reference power supply.

A third object of the present invention is to provide a pressure distribution measuring method using a pressure distribution measuring apparatus according to the first aspect, wherein a value p for selecting a driving electrode in P driving electrodes is set to 1, A first step of setting a value l for selecting a measurement group in the individual measurement group to 1 and setting a value k for selecting detection electrodes in K detection electrodes in the individual measurement group to 1; a second step of detecting a detection value ADC_l_k of a detection electrode corresponding to a k-th input of the multi-channel ADC provided in the l-th measurement group; l is equal to L, and if it is not the same, it is judged that all the measurement groups are not circulated, l is added to 1, and the second step is repeated. In the same case, the set of detection values corresponding to the k- To a control unit; a fourth step of setting a detected value ADC (p, q) of a node corresponding to the p-th driving electrode and the q-th detecting electrode; determining whether k and K are the same, determining that all the detection electrodes assigned to the individual measurement group are circulated if they are the same, and adding 1 to k if they are not the same and moving to the second step; And if k and K are equal, it is determined whether p and P are the same. In the case where k and K are the same, it is determined that all the driving electrodes are circulated and terminated, and if not, p is incremented by 1 to move to the second step Channel pressure distribution measuring apparatus according to the present invention.

In the fourth step, detection values are assigned based on the following equation (1).

[Equation 1]

A fourth object of the present invention is to provide a method for converting a digital output value measured by a pressure distribution measurement method according to the second or third object to a physical quantity, ; A second step of performing fine adjustment; And a third step of converting the digital output value into a physical quantity through the fine adjustment. The method of the present invention may be achieved by a method of converting a physical quantity of a digital output value measured by a pressure distribution measuring method.

The first step of the fourth object of the present invention is characterized in that the first step comprises: a 1-1 step of applying a pressure set in the detection area of the sensor; A first step of calculating a sum of the number of nodes whose output value is not 0, an output value and an average output value; Selecting one node and determining whether the output value of the selected node is 0; If the output value of the selected node is 0, the gain of the node having the output value of 0 is set as the basic gain. Otherwise, the gain of the selected node is calculated. If the calculated node gain is out of the predetermined range, (1-4); And (1-5) repeating the steps 1-3 and 1-4 until the gain for all the nodes is set.

In addition, the pressure set in the step 1-1 is calculated by the following equation (2), and the average output value is calculated by the following equation (3) in the step 1-2.

&Quot; (2) "

FORCE_BALANCING = {(P_MAX * A_SENSOR) + (P_MIN * A_SENSOR)} / 2

&Quot; (3) "

AVERAGE_NONZERO = SUM_NONZERO / N_NONZERO

In the above equation (2), P_MAX is the maximum detectable pressure of the sensor, A_SENSOR is the area of the sensor detection area, P_MIN is the minimum detectable pressure of the sensor,

In Equation (3), SUM_NONZERO is the sum of the detection values of nodes whose output value is not 0, and N_NONZERO is the number of nodes whose output value is not zero.

In addition, the node gain calculated in the step 1-4 may be calculated by the following equation (4).

&Quot; (4) "

G_ij = AVERAGE_NONZERO / A_ij

Herein, AVERAGE_NONZERO is an average value obtained through Equation (3), and A_ij is a digital output value of a node corresponding to the intersection of the i-th driving electrode and the j-th detection electrode.

The method for fine adjustment in the second step may further include: a second step of setting the number N of fine adjustment points, setting each of the forces F_i corresponding to individual fine adjustment points, and setting i to 1; Step 2-2 of applying a force F_i and obtaining an output value ADC0_pq of the individual node corresponding thereto (p is the index of the driving electrode and q is the index of the detecting electrode); A second step of calculating an output value ADC_pq whose gain is adjusted by multiplying the output ADC0_pq of each node by the individual node gain G_pq; Calculating ADC_SUM_i which is a sum of the adjusted output value ADC_pq and storing the result; i is incremented by 1, i is determined to be greater than the number N of fine adjustment points, and if i is not greater than N, step 2-2 is performed; (i) is greater than N, j is set to 1, and the equation of the curve function Y_j corresponding to ADC_SUM_j, F_j and ADC_SUM_ (j + 1), F_ Step 6; And j is incremented by 1, j is determined to be greater than N-1, and if j is not greater than N-1, the process proceeds to step 2-6, otherwise, And the like.

In the third step, a method of converting into a physical quantity includes: a 3-1 step of setting an index p of P drive electrodes to 1 and setting an index q of Q detection electrodes to 1; a third step (2-2) of detecting an output value ADC0 (p, q) of a node corresponding to an intersection of the p-th driving electrode and the q-th detecting electrode; A third step of calculating an output value ADC (p, q) whose gain is adjusted by multiplying the output value ADC0 (p, q) of the individual node by the gain G (p, q) of the individual node; (P, q), and calculating a pressure physical quantity using the curve function of the section to which the ADC (p, q) belongs; if it is determined that circulation of all driving electrodes is completed, if p is not equal to P, it is determined that circulation of all driving electrodes is completed; otherwise, p is increased by 1 and step S3-2 is performed; And if p and P are the same, it is determined whether q and Q are the same. If it is the same, it is determined that the circulation is completed for all the detection electrodes and the process ends. Otherwise, q is incremented by 1 and the process moves to step S3-2 And (3-6).

Then, in the step 3-4, the pressure physical quantity is calculated by using the curve function as the following equation (5).

&Quot; (5) "

P (p, q) = Y_i {ADC (p, q)}

Here, P (p, q) is a physical pressure value of a node corresponding to the p-th driving electrode 101 and the q-th detecting electrode 102, i is an index of a section to which ADC (p, q) belongs, is a function of a curve corresponding to the section to which (p, q) belongs.

According to an embodiment of the present invention, a measurement speed of a multi-channel pressure distribution measurement device can be improved, and a stacked structure can be used to reduce the size of a control board, It is possible to improve the added value of the product.

In addition, according to the embodiment of the present invention, it is possible to drive a sensor composed of a large number of driving electrodes and detecting electrodes at a high speed, to reduce the manufacturing cost of the pressure distribution measuring apparatus, to provide a physical pressure value at a high speed .

It should be understood, however, that the effects obtained by the present invention are not limited to the above-mentioned effects, and other effects not mentioned may be clearly understood by those skilled in the art to which the present invention belongs It will be possible.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate preferred embodiments of the invention and, together with the description, serve to further the understanding of the technical idea of the invention, It should not be construed as limited.
1 is a block diagram showing the configuration of a multi-channel pressure distribution measuring apparatus,
2 is an enlarged view of the matrix sensor unit,
3 is a flowchart of a pressure distribution measuring method using a multi-channel pressure distribution measuring apparatus,
4 is a block diagram illustrating a configuration of a multilayer matrix sensor control board according to an embodiment of the present invention.
FIG. 5 is an exploded perspective view of a multilayer matrix sensor control board according to an embodiment of the present invention, FIG.
FIG. 6 is a flowchart of a method for measuring a high-speed pressure distribution using a multi-channel pressure distribution measuring apparatus according to an embodiment of the present invention.
7 is a structural diagram of a high-speed pressure distribution measurement circuit according to an embodiment of the present invention;
Figure 8 is a block diagram of the specific measurement group of Figure 7,
9 is a flowchart of a method of controlling a high-speed pressure distribution measurement circuit according to an embodiment of the present invention,
10 is a flowchart of a method for converting a digital value into a physical quantity according to an embodiment of the present invention;
11 is a flowchart of an individual node gain adjustment method through planarization in the conversion method of FIG. 10,
Fig. 12 is a flowchart of the fine adjustment method of Fig. 10,
13 is a diagram of a section used in the fine adjustment method of Fig. 12,
14 is a flowchart of a real-time physical quantity conversion method according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features, and advantages of the present invention will become more readily apparent from the following description of preferred embodiments with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms. Rather, the embodiments disclosed herein are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art.

In this specification, when an element is referred to as being on another element, it may be directly formed on another element, or a third element may be interposed therebetween. Also in the figures, the thickness of the components is exaggerated for an effective description of the technical content.

Embodiments described herein will be described with reference to cross-sectional views and / or plan views that are ideal illustrations of the present invention. In the drawings, the thicknesses of the films and regions are exaggerated for an effective description of the technical content. Thus, the shape of the illustrations may be modified by manufacturing techniques and / or tolerances. Accordingly, the embodiments of the present invention are not limited to the specific forms shown, but also include changes in the shapes that are produced according to the manufacturing process. For example, the area shown at right angles may be rounded or may have a shape with a certain curvature. Thus, the regions illustrated in the figures have attributes, and the shapes of the regions illustrated in the figures are intended to illustrate specific forms of regions of the elements and are not intended to limit the scope of the invention. Although the terms first, second, etc. have been used in various embodiments of the present disclosure to describe various components, these components should not be limited by these terms. These terms have only been used to distinguish one component from another. The embodiments described and exemplified herein also include their complementary embodiments.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. The terms "comprises" and / or "comprising" used in the specification do not exclude the presence or addition of one or more other elements.

In describing the specific embodiments below, various specific details have been set forth in order to explain the invention in greater detail and to assist in understanding it. However, it will be appreciated by those skilled in the art that the present invention may be understood by those skilled in the art without departing from such specific details. In some instances, it should be noted that portions of the invention that are not commonly known in the description of the invention and are not significantly related to the invention do not describe confusing reasons to explain the present invention.

Hereinafter, the configuration, function, and operation method of a multi-channel pressure distribution measuring apparatus according to an embodiment of the present invention will be described. First, the configuration of a pressure distribution measuring apparatus having a matrix sensor unit and a pressure distribution measuring method using the measuring apparatus will be described. 1 is a block diagram showing the configuration of a multi-channel pressure distribution measuring apparatus. 2 is an enlarged view of the matrix sensor unit. 3 is a flowchart of a pressure distribution measuring method using a multi-channel pressure distribution measuring apparatus.

As shown in FIG. 1, the multi-channel pressure distribution measuring apparatus may include a driving unit, a matrix sensor unit, a detecting unit, a controller, a communication unit, a host, and the like as a whole.

The matrix sensor unit 100 is disposed such that the driving electrode 101 and the sensing electrode 102 are orthogonal to each other and the driving electrode 101 is connected to the driving unit 130 and the sensing electrode 102 is connected to the sensing unit 110 .

The driving unit 130 includes a first driving power source 131, a second driving power source 134, and a driving switch 132. The driving unit 130 operates the driving switch 132 to apply the output of the first driving power source 131 to the selected driving electrode 101 and apply the second driving power to the remaining driving electrode 101 And the output of the power supply 134 is applied.

The detection unit 110 includes a detection power source 112, a detection circuit 113, and a detection switch 111. The detection unit 110 operates the detection switch 111 to connect the selected detection electrode 102 to the detection circuit 113 and connect the remaining detection electrode 102 to the detection power source 112 in accordance with an instruction from the control unit 120 do.

In general, the output of the second driving power supply 134 and the output of the detecting power supply 112 are the same, but in special cases, the two outputs may be different. The description of the present invention assumes that the output of the second driving power supply 134 and the output of the detecting power supply 112 are the same unless otherwise specified. For convenience of explanation, the output of the first driving power source 131 is referred to as a first voltage, and the output of the second driving power source 134 and the detecting power source 112 are assumed to be the same and referred to as a second voltage. The output of the first driving power supply 134, the second driving power supply 134, and the detecting power supply 112 may have a current shape or a periodicity such as a sinusoidal wave or a square wave, Indicate that there is a possibility

2, the matrix sensor unit 100 includes a sensing electrode 102, a sensing electrode 102 and a driving electrode 101 which are disposed orthogonally to each other. The sensing electrode 102 and the driving electrode 101 intersect with each other. When the pressure is applied to the intersection 103 of the piezoelectric element 101, the impedance 104 such as the resistance or the capacitance changes.

Hereinafter, a general operation method of the pressure distribution measuring apparatus having the above-mentioned matrix sensor unit will be described. As shown in Fig. 3, in the step S1, the pressure distribution measuring apparatus sets i, which is a value for selecting the driving electrode 101, to 1. i is a natural number of 1 or more and N or less. Here, N means the total number of driving electrodes and is a natural number.

In step S2, the pressure distribution measuring apparatus sets j, which is a value for selecting a detection electrode, to 1. j is a natural number equal to or greater than 1 and equal to or less than M. Here, M represents the total number of detection electrodes and is a natural number.

Then, the pressure distribution measuring apparatus applies an appropriate driving output to the driving electrode 101. [ Specifically, in step S3, the pressure distribution measuring apparatus applies a first voltage to the i-th driving electrode 101, and applies a second voltage to the remaining driving electrode 101 in step S4.

The pressure distribution measuring device suitably connects the detecting electrode 102 and the detecting unit 110. Specifically, in step S5, the pressure distribution measuring apparatus connects the jth detection electrode 102 to the detection circuit 113, and applies the second voltage to the remaining detection electrode 102 in step S6.

In step S7, the pressure distribution measuring apparatus detects an input to the intersection 103 between the i-th driving electrode 101 and the j-th detecting electrode 102 based on the detection voltage detected from the j-th detection electrode 102 do.

In step S8, the pressure distribution measuring device compares j and M. The pressure distribution measuring apparatus performs step S10 if j is greater than M, and performs step S9 if j is not greater than M.

In step S9, the pressure distribution measuring apparatus increases j by 1, and then performs step S5 again.

Further, in step S10, the pressure distribution measuring device compares i and N. The pressure distribution measuring device terminates the operation when i is greater than N, and performs step S11 if i is not greater than N. [

In step S11, the pressure distribution measuring device increments i by 1 and performs step S3 again.

As described above, in order to constitute an accurate multi-touch measuring circuit, a first voltage is outputted to the selected driving electrode 101, the selected detecting electrode 102 is connected to the detecting circuit, and the remaining driving electrode 101 and the remaining detecting The process of applying the second voltage to the electrode 102 is essential.

For this application, a driving switch 132 and a detecting switch 111 are required, and a conventional two-channel analog switch is added to each driving electrode 101 and each detecting electrode 102. However, when a two-channel analog switch is provided for each of the individual electrodes, the size of the circuit increases and the manufacturing cost increases.

Particularly, when the number of the driving electrodes 101 and the number of the detecting electrodes 102 of the matrix sensor unit 100 is increased, the size of a printed circuit board (PCB) on which the entire circuit is mounted can not be practically used There is a disadvantage that the manufacturing cost increases sharply.

In the embodiment of the present invention, technical features that can reduce the size of the circuit board to solve such a problem will be described below. 4 is a block diagram illustrating a configuration of a multilayer matrix sensor control board according to an embodiment of the present invention. 5 is an exploded perspective view of a multilayer matrix sensor control board according to an embodiment of the present invention.

That is, FIG. 4 shows a configuration diagram of a control board that can be reduced in size. As shown in FIG. 4, the sensor unit 100 is connected to the main board 200 and the driving circuit 140. The drive electrode 101 of the sensor unit 100 is connected to the drive circuit 405 and the detection electrode 102 is connected to the detection circuit 113 of the main board 200)

The control unit 120 is provided on the main board 200 and controls the driving circuit 140 and the detection circuit 113 to input a signal to the driving electrode 101, Output is detected. The power supply unit 150 of the main board 200 is connected to the driving circuit 140 and applies power to the driving circuit 140 and the detection circuit 113.

5, the main board 200 and the driving circuit 140 are mounted on a separate printed circuit board (PCB), and the communication between the control unit 120 and the driving circuit 140, The driving circuit board 150 and the driving circuit 140 are connected through the driving circuit board connector 141 and the main board connector 201. These connectors 141 and 201 can be configured using the DF40 series of HRS in a specific embodiment.

4 and 5, it is possible to mount a large number of driving and detecting components while limiting the size (area) of the control board with respect to the multi-channel sensor, thereby reducing the manufacturing cost and the manufacturing defect rate Can be achieved.

In addition, when a plurality of driving electrodes 101 and detecting electrodes 102 are present, it takes a long time to obtain one pressure distribution shape image. Conventionally, this problem has been solved by combining a plurality of sensors and a plurality of driving electrodes 101 and sensing electrodes 102. However, this method has the same cost increase as the sensor manufacturing cost is increased and a plurality of control boards are used.

Accordingly, in order to solve such a problem, an embodiment of the present invention provides a method of acquiring a pressure distribution image at a high speed. FIG. 6 is a flowchart illustrating a method for measuring a high-speed pressure distribution using a multi-channel pressure distribution measuring apparatus according to an embodiment of the present invention. That is, FIG. 6 is a flowchart of a method for obtaining a pressure distribution image at a high speed. FIG. 6 is a block diagram illustrating a pressure distribution measurement system according to an embodiment of the present invention.

As shown in Fig. 6, the index q for selecting the detection electrode 102 is set to 1 in step S21. The number of detection electrodes is Q.

In step S22, a driving signal, that is, the first driving power source 131, is applied to all the driving electrodes 101. [

In step S23, the measurement value S_q of the q-th detection electrode 102 is detected.

In step S24, it is determined whether or not the measured value S_q of the detection electrode 102 is equal to or larger than a preset value TH_q. TH_q is a threshold value for determining whether or not a pressure is applied to the detection electrode 102. [

If the measured value S_q of the detecting electrode 102 is equal to or larger than a predetermined value TH_q, the value of the variable T_q for determining whether or not the pressure of the q-th detecting electrode 102 is applied through the step S25-1 Is set to TRUE.

If the measured value S_q of the detection electrode 102 is smaller than the predetermined value TH_q, the value of the variable T_q for determining whether the q-th detection electrode 102 is applied through the step S25-2 Set to FALSE.

In step S26, it is determined whether q and Q are equal to each other. It is determined that all of the detection electrodes 102 have not been measured yet, and q is incremented by 1 in step S27, followed by step S23. If q and Q are equal, it is determined that all the detection electrodes 102 have been measured, and the flow proceeds to step S27.

Up to step S26, it is intended to grasp the detection electrode 102 to which the pressure is physically applied. In the subsequent step, the detection operation is performed only on the detection electrode 102 to which the pressure is physically applied.

The value p for selecting the driving electrode 101 is set to 1 in step S27. P is the total number of driving electrodes.

The value q for selecting the detection electrode 102 is set to 1 in step S28. Q is the total number of detection electrodes.

In step S29, whether a physical pressure is applied to the q-th detection electrode 102 is determined through a variable T_q. If T_q is TRUE, the pressure is applied, and the flow proceeds to step S30 where actual pressure detection of the node corresponding to the currently selected drive electrode p and detection electrode q is performed. If T_q is FALSE, it is determined that there is no pressure, and the flow moves to step S31.

In step S31, a detection value corresponding to the detection electrode 102 to which no pressure is applied and the selected driving electrode 101 is set to zero.

In step S32, p and P are compared. If p and P are not the same, it is determined that all the driving electrodes 101 have not been searched yet, and the process moves to step S33. If p and P are equal to each other, it is determined that all the driving electrodes 101 have been searched, and the process proceeds to step S34.

In step S33, p is incremented by one and the process moves to step S29.

In step S34, q and Q are compared. If q and Q are not equal, it is determined that all the detection electrodes 102 have not been searched yet, and the process moves to step S35. If q and Q are equal, it is determined that all the detection electrodes 102 have been searched, and the scan is terminated.

In step S35, q is incremented by one and the process moves to step S29.

Hereinafter, a structure and a method for further improving the detection speed of the pressure distribution measuring apparatus will be described. 7 is a structural diagram of a high-speed pressure distribution measuring circuit according to an embodiment of the present invention. Fig. 8 shows a configuration diagram of the specific measurement group of Fig. 7. Fig. 9 is a flowchart of a method of controlling a high-speed pressure distribution measurement circuit according to an embodiment of the present invention.

That is, in an embodiment of the present invention, in order to further improve the detection speed, a plurality of detection electrodes provided in the sensor unit may be grouped into a plurality of measurement groups by a specific number, A detection circuit is connected, a multi-channel ADC is connected to each measurement group, and each multi-channel ADC is connected to a control unit.

Specifically, as shown in FIG. 7, the detection electrodes 102 of the matrix sensor unit 100 are grouped into K groups and connected to L measurement groups of the measurement group 1, the measurement group 2, As shown in FIG.

7, the individual measurement groups detect an electrical change according to the pressure generated in the grouped detection electrodes 102 and exchange data with the control unit 102 through digital communication. In a specific embodiment, digital communication may utilize SPI, I2C, RS232C, etc. for inter-board communication.

Fig. 8 shows the configuration diagram of the first measurement group in more detail. Each measurement group is configured as shown in FIG. As shown in FIG. 8, the first detection electrode 102 of the first measurement group is connected to the negative input of the operational amplifier 105. Both inputs of the operational amplifier 105 are connected to the reference power supply 106. The negative input of the operational amplifier 105 is again connected to the output of the operational amplifier 105 via the feedback impedance 107 and its output is again connected to the input of the multi-channel ADC 108. The second detection electrode 102 of the first measurement group is also connected to the negative input of the operational amplifier 105. Both inputs of the operational amplifier 105 are connected to the reference power supply 106. The negative input of the operational amplifier 105 is again connected to the output of the operational amplifier 105 via the feedback impedance 107 and its output is again connected to the input of the multi-channel ADC 108. This connection is repeated so that the last Kth detection electrode 102 of the first measurement group is connected to the negative input of the operational amplifier 105. Both inputs of the operational amplifier 105 are connected to the reference power supply 106. The negative input of the operational amplifier 105 is again connected to the output of the operational amplifier 105 via the feedback impedance 107 and its output is again connected to the input of the multi-channel ADC 108.

In the conventional method, one operational amplifier is usually connected to the plurality of detection electrodes 102 through a multiplexer (MUX). A multiplexer is an analog switch element having a plurality of inputs and an output. In the conventional method, a plurality of detection electrodes are connected to a plurality of inputs of a multiplexer, an operational amplifier is provided to one output of the multiplexer, Are sequentially connected to the operational amplifier provided at the output through a switch inside the multiplexer. However, in this case, when a switch is used to connect an input and an output, a switching noise is generated as soon as the input and the output are connected. Since this switching noise disappears after a certain time, it is necessary to wait for a certain time after switching for accurate measurement, which inevitably leads to a decrease in the measurement speed.

Therefore, in one embodiment of the present invention, the operational amplifier 105 is disposed on all of the detection electrodes 102, and the output of the operational amplifier 105 is connected to the multi-channel ADC 108 to prevent a decrease in the measurement speed due to the switching noise . This method can be called a parallel detection method, unlike the conventional sequential detection. However, a plurality of detection electrodes 102 can not be detected at the same time by using one multi-channel ADC 108. The first reason is that the number of inputs of the multichannel ADC 108 is physically limited and secondly the multichannel ADC 108 also detects the amount of electrical change of the individual detection electrodes 102 through internal switching This is because the switching wait time is needed although it is improved compared to the conventional sequential detection.

In order to solve such a problem, in an embodiment of the present invention, the individual multi-channel ADCs 108 are installed in a plurality of detection groups, and data measured by the plurality of ADCs 108 at one time is detected, The control unit 102 reads through the same digital communication as shown in FIG. In particular, digital communications such as SPI can simultaneously measure the output of multiple ADCs, thus enabling a dramatic reduction in detection time.

Hereinafter, the measurement of the high-speed pressure distribution using the high-speed pressure distribution measurement circuit will be described. That is, the above-mentioned FIG. 9 shows the driving sequence of the control circuit capable of high-speed measurement shown in FIG. 7 and FIG.

As shown in Fig. 9, the value p for selecting the driving electrode 101 is set to 1 in step S41. The number of driving electrodes is P number.

The value k for selecting the detection electrode 102 of the individual measurement group is set to 1 in step S42. The total number of detection electrodes 102 assigned to the individual measurement groups is K. [

The value l for selecting the individual measurement group is set to 1 in step S43. The total number of measurement groups is L.

In step S44, the detection value ADC_l_k of the detection electrode 102 corresponding to the k-th input of the multi-channel ADC 108 corresponding to the l-th measurement group is detected.

In step S45, it is determined whether l is equal to L or not. If L and l are not equal, it is determined that all the measurement groups are not circulated, and the flow moves to step S46. If L and l are the same, it is determined that all measurement groups have been circulated, and the flow moves to step S47.

In step S46, l is incremented by one and the process moves to step S44.

In step S47, the control unit 120 transmits a set of detected values corresponding to the kth of all measurement groups. Also, although steps S44, S45, and S46 are described as being performed sequentially in the flowchart, they are performed simultaneously in actual implementation. As a result, the measurement speed can be improved.

In step S48, detection values of nodes corresponding to the driving electrode p and the detection electrode q are assigned based on the following equation (1).

[Equation 1]

q = (1 - 1) * K + k

In step S49, it is determined whether k and K are the same. If k and K are equal, it is determined that all the detection electrodes 102 assigned to the individual measurement group are circulated, and the process moves to step S51. If k and K are not the same, go to S50.

In step S50, the value of k is incremented by one and the process moves to step S44.

In step S51, it is determined whether p and P are the same. If p and P are the same, it is determined that all the driving electrodes 101 are circulated, and the process is terminated. If p and P are not the same, the flow goes to step S52.

In step S52, p is incremented by one and the process moves to step S44.

As mentioned above, the pressure distribution measuring device is a device for grasping the physical quantity of the applied pressure together with the distribution shape of the pressure. However, since the detection circuit of the pressure distribution measuring apparatus only provides the digital value corresponding to the pressure, it is necessary to convert the digital value into the actual physical quantity. To do this, it is necessary to perform an operation to map the digital numerical value and the actual pressure physical quantity.

10 is a flowchart of a method of converting a digital value into a physical quantity according to an embodiment of the present invention. As shown in FIG. 10, in the method of converting a digital value into a physical quantity, a gain (or a gain) of an individual node is adjusted through a flattening process in step S61. In step S62, a digital value and a physical quantity are mapped do.

Hereinafter, the steps of adjusting the gains of individual nodes through the above-mentioned flattening process and the steps of converting digital values and physical quantities through fine adjustment will be described in detail.

11 is a flowchart of a method of adjusting individual node gains through planarization in the conversion method of FIG. The planarization algorithm of FIG. 11 has the purpose of adjusting the gain of individual nodes to reduce the deviation of responses existing between the nodes.

As shown in FIG. 11, in step S71, the entire detection region of the sensor is applied with a constant force. The applied force is typically set to an intermediate value between the minimum pressure value and the maximum pressure value of the sensor. The force (FORCE_BALANCING) can be obtained by the following equation (2).

&Quot; (2) "

FORCE_BALANCING = {(P_MAX * A_SENSOR) + (P_MIN * A_SENSOR)} / 2

In Equation (2), P_MAX denotes the maximum detectable pressure of the sensor, A_SENSOR denotes the area of the sensor detection region, and P_MIN denotes the minimum detectable pressure of the sensor.

In step S72, the detection values of all the sensor nodes are obtained through the detection circuit 113, and then the number of nodes whose detection values are not zero is grasped. A node whose detection value is not 0 is a node to which pressure is not applied.

In step S73, the sum of the non-zero detection values among the detection values of all the sensor nodes is calculated.

In step S74, the average value (AVERAGE_NONZERO) of all the sensor nodes, which are not zero, is calculated. The calculation formula is as shown in [Equation 3].

&Quot; (3) "

AVERAGE_NONZERO = SUM_NONZERO / N_NONZERO

SUM_NONZERO in Equation (3) is the sum of the detected values of the non-zero detected nodes obtained in S73 and N_NONZERO is the number of non-zero detected nodes obtained in S72.

In step S75, one node is selected.

In step S76, it is determined whether the detected value of the selected node is 0 or not. If the detected value of the node is 0, the process proceeds to step S78. If the detected value of the node is not 0, the process proceeds to step S77.

In step S78, the gain of the node having the detected value of 0 is set as the basic gain, and then the flow proceeds to step S80. The value of the basic gain is usually set to 1.0.

In step S77, the gain of the selected node is calculated. The calculation of the gain G_ij of the (i, j) -th node follows Equation (4).

&Quot; (4) "

G_ij = AVERAGE_NONZERO / A_ij

Here, AVERAGE_NONZERO is an average value obtained through Equation (3), and A_ij is a digital detection value of a node corresponding to the intersection point of the i-th driving electrode 101 and the j-th detecting electrode 102.

In step S79, it is determined whether the gain of the node calculated through Equation (4) is within a specified range. If the node's gain is outside the specified range, the node's gain is reset to the default gain. The default gain is typically 1.0. The range of gains for a given node is between 0.5 and 2.0.

In step S80, it is determined whether or not the gain is calculated for all the nodes. If the gain is calculated for all the nodes, the process ends. Otherwise, the process moves to step S81.

In step S81, the mobile node moves to the next node, detects the detected value of the node, and moves to step S76.

Next, the method of changing the physical quantity of the digital value by fine adjustment (S62) will be described in more detail. 12 is a flowchart of the fine adjustment method of FIG. That is, FIG. 12 shows a flowchart of an algorithm for converting a detection value of a node whose gain is adjusted to an actual physical quantity.

As shown in Fig. 12, in step S91, the number N of fine adjustment points is set. N is an arbitrary natural number greater than zero.

In step S92, the force F_i corresponding to the individual fine adjustment point is set. Normally, F_1 is the force corresponding to the minimum detection pressure of the sensor and F_N is the force corresponding to the maximum detection pressure of the sensor.

I is set to 1 in step S93.

In step S94, the force F_i is applied and the detection value ADC0_pq of the corresponding node is obtained. p is an index of the driving electrode 101, and q is an index of the detecting electrode 102.

In step S95, the gain ADC_pq is calculated by multiplying the output ADC0_pq of each node by the gain G_pq of the individual node obtained in the above-mentioned FIG. 11.

In step S96, the sum ADC_SUM_i of ADC_pq is calculated and the result is stored.

In step S97, i is incremented by one.

In step S98, it is determined whether i is greater than the number N of fine adjustment points. If i is not greater than N, the process moves to step S94. Otherwise, the flow proceeds to step S99.

In step S99, j is set to 1.

In step S100, a formula of a curve Y_j corresponding to (ADC_SUM_j, F_j) and (ADC_SUM_ (j + 1), F_ (j + 1)) is calculated. The formula of Y_j can be applied to a method such as a first order linear fitting, a second order linear fitting, or a nonlinear curve fitting.

In step S101, j is incremented by one.

In step S102, it is determined whether j is greater than N-1. If j is not greater than N-1, the process moves to step S100. Otherwise, the process ends.

FIG. 13 is a diagram of a section used in the fine adjustment method of FIG. 12; FIG. That is, FIG. 13 is a schematic representation of the step S100 in the fine adjustment method of FIG.

As shown in FIG. 13, the abscissa is the sum of the detected gains (ADC_SUM) and the ordinate is the applied force (F).

13 shows the case where the number of fine adjustment points N is 4. In this case, the interval for fitting the curve is N-1, which is 3. Here, the sections are I_1, I_2, and I_3. The data for fitting the curve of the section I_1 is (ADC_SUM_1, F_1) and (ADC_SUM_2, F_2), and the straight line formula Y_1 can be obtained by applying the curve fitting algorithm that is conventionally used here. Similarly, the data for fitting the curve of the section I_2 are (ADC_SUM_2, F_2) and (ADC_SUM_3, F_3), and the straight line formula Y_2 can be obtained by applying the curve fitting algorithm which is conventionally used here. Similarly, the data for fitting the curve of the section I_3 are (ADC_SUM_3, F_3) and (ADC_SUM_4, F_4), and the straight line formula Y_1 can be obtained by applying the curve fitting algorithm which is conventionally used here.

Accordingly, from the above-described FIG. 10 to FIG. 13, a formula for converting the detection value of the measurement circuit into the actual pressure physical quantity can be obtained.

14 is a flowchart of a real-time physical quantity conversion method according to an embodiment of the present invention. Jug FIG. 14 shows a flowchart for converting the detection value of the measurement circuit into the actual pressure physical quantity in real time using this formula.

As shown in Fig. 14, the index p of the driving electrode 101 is set to 1 in step S110. The number of the driving electrodes 101 is P.

The index q of the detection electrode 102 is set to 1 in step S111. The number of the detection electrodes 102 is Q.

The detection value ADC0 (p, q) of the node corresponding to the intersection of the p-th drive electrode 101 and the q-th detection electrode 102 is detected in step S112.

In step S113, the gain ADC (p, q) is calculated by multiplying the detection value ADC0 (p, q) of the individual node by the gain G (p, q) of the individual node.

In step S114, the subsection of the ADC (p, q) is identified.

In step S115, the pressure physical quantity is calculated using Equation 5 using the curve function of the section to which the ADC (p, q) belongs.

&Quot; (5) "

P (p, q) = Y_i {ADC (p, q)}

Here, P (p, q) is a physical pressure value of a node corresponding to the p-th driving electrode 101 and the q-th detecting electrode 102, i is an index of a section to which ADC (p, q) belongs, is a function of a curve corresponding to the section to which (p, q) belongs.

In step S116, it is determined whether p and P are the same. It is determined that the circulation of all the driving electrodes 101 is completed, and the flow proceeds to step S118. Otherwise, the flow proceeds to step S117.

In step S117, p is incremented by one and the process moves to step S112.

In step S118, it is determined whether q and Q are the same. It is determined that the circulation is completed for all the detection electrodes 102 and the process is terminated. Otherwise, the process moves to step S119.

In step S119 (1410), q is incremented by one and the process moves to step S112.

It should be noted that the above-described apparatus and method are not limited to the configurations and methods of the embodiments described above, but the embodiments may be modified so that all or some of the embodiments are selectively combined .

100:
101: driving electrode
102:
103: intersection (node)
104: Impedance
105: operational amplifier
106: Reference power source
107: feedback impedance
108: Multi-channel ADC
110:
111: Detection switch
112: detection power source
113: Detection circuit
120:
130:
131: first driving power source
132: drive switch
134: second driving power source
140: drive circuit board
141: drive circuit connector
150:
200: Motherboard
300:
400: Host
500: Matrix sensor control board

Claims (15)

And a matrix sensor unit having a plurality of driving electrodes formed on the substrate and having a plurality of detecting electrodes configured to intersect with the driving electrodes, wherein a distribution of the applied pressure is obtained by measuring the amount of change in electric potential at the intersection of the driving electrode and the detecting electrode, A pressure distribution measuring method using a multi-channel pressure distribution measuring apparatus for measuring pressure on each intersection,
The multi-channel pressure distribution measuring apparatus includes a first driving power source for applying a first voltage to a selected one of the plurality of driving electrodes, a second driving power source for applying a second voltage to the unselected driving electrode, ; A detection circuit connected to the selected detection electrode among the plurality of detection electrodes, a detection power source connected to the unselected detection electrode, and a detection unit having a detection switch; And a control unit for controlling the drive switch and the detection switch,
A first step of setting an index q for selecting a detection electrode in Q detection electrodes to 1 and applying a first voltage to all the driving electrodes by a first driving power source;
a second step of detecting a measurement value S_q of the q-th detection electrode;
A third step of setting the value of the pressure application judgment variable T_q to TRUE if S_q is equal to or greater than a preset value TH_q and setting T_q to FALSE when the value of S_q is smaller than the preset value TH_q;
the second and third steps are repeated until q becomes equal to Q. If the same is true, it is determined that all the detection electrodes have been measured, and the value p for selecting the drive electrodes in the P drive electrodes is set to 1 A fourth step of setting a value q for selecting detection electrodes in Q detection electrodes to 1;
(P, q) f of the node which is the intersection of the p-th driving electrode and the q-th detecting electrode when T_q is TRUE, and if it is FALSE, it is determined that there is no pressure, A fifth step of setting a detection value at an intersection of the electrodes to 0;
if p and P are not the same, repeating the fifth step by adding 1 to p, and adding q to q when q and Q are not the same, and repeating the fifth step; And
and a seventh step of terminating the scan when p and P are the same and q and Q are the same.
The method according to claim 1,
The detection unit and the control unit are provided on a main board, and the driving unit is provided on a driving circuit board,
Wherein the main board and the driving circuit board connected to the matrix sensor unit are laminated by a connector.
delete 3. The method according to claim 1 or 2,
Wherein the plurality of detection electrodes included in the matrix sensor unit are grouped into k measurement groups,
Each of the grouped L measurement groups includes k operational amplifiers connected to k detection electrodes, one multichannel ADC connected to the outputs of k operation amplifiers and receiving detection values detected from the k detection electrodes, And measuring the pressure distribution using the multi-channel pressure distribution measuring apparatus.
5. The method of claim 4,
The multi-channel ADC provided in each of the L measurement groups is connected to the control unit,
Wherein the multi-channel ADC receives a detection value detected at each of the k detection electrodes, and transmits the sum of the detection values to the control unit.
6. The method of claim 5,
Wherein the negative input of each of the operational amplifiers is connected to the detection electrode and is connected to the output through a feedback impedance and both inputs are connected to a reference power supply.
And a matrix sensor unit having a plurality of driving electrodes formed on the substrate and having a plurality of detecting electrodes configured to intersect with the driving electrodes, wherein a distribution of the applied pressure is obtained by measuring the amount of change in electric potential at the intersection of the driving electrode and the detecting electrode, A pressure distribution measuring method using a multi-channel pressure distribution measuring apparatus for measuring pressure on each intersection,
The multi-channel pressure distribution measuring apparatus includes a first driving power source for applying a first voltage to a selected one of the plurality of driving electrodes, a second driving power source for applying a second voltage to the unselected driving electrode, ; A detection circuit connected to the selected detection electrode among the plurality of detection electrodes, a detection power source connected to the unselected detection electrode, and a detection unit having a detection switch; And a control unit for controlling the drive switch and the detection switch, wherein a plurality of detection electrodes included in the matrix sensor unit are grouped into k measurement groups, and each of the grouped L measurement groups includes k detection electrodes Channel ADC connected to the outputs of the k averaging amplifiers and receiving detection values detected from the k detection electrodes,
The value p for selecting the driving electrode in the P driving electrodes is set to 1, the value l for selecting the measurement group in the L measurement groups is set to 1, and the detection electrodes are selected in the K detection electrodes in the individual measurement group Setting a value k to 1;
a second step of detecting a detection value ADC_l_k of a detection electrode corresponding to a k-th input of the multi-channel ADC provided in the l-th measurement group;
l is equal to L, and if it is not the same, it is judged that all the measurement groups are not circulated, l is added to 1, and the second step is repeated. In the same case, the set of detection values corresponding to the k- To a control unit;
a fourth step of setting a detected value ADC (p, q) of a node corresponding to the p-th driving electrode and the q-th detecting electrode;
determining whether k and K are the same, determining that all the detection electrodes assigned to the individual measurement group are circulated if they are the same, and adding 1 to k if they are not the same and moving to the second step; And
If k and K are the same, it is determined whether p and P are the same. If they are the same, all driving electrodes are judged to be circulated, and the process is terminated. Otherwise, 1 is added to p to move to the second step And measuring the pressure distribution using the multi-channel pressure distribution measuring apparatus. 8. The method of claim 7,
And the fourth step is to assign a detection value according to the following equation (1): < EMI ID = 1.0 >
[Equation 1]

A method for converting a digital output value measured by a pressure distribution measurement method according to claim 7 into a physical quantity,
A first step of adjusting individual node gains through planarization;
A second step of performing fine adjustment; And
And a third step of converting the digital output value into a physical quantity through the fine adjustment.
10. The method of claim 9,
In the first step,
A first step of applying pressure set in a detection area of the sensor;
A first step of calculating a sum of the number of nodes whose output value is not 0, an output value and an average output value;
Selecting one node and determining whether the output value of the selected node is 0;
If the output value of the selected node is 0, the gain of the node having the output value of 0 is set as the basic gain. Otherwise, the gain of the selected node is calculated. If the calculated node gain is out of the predetermined range, (1-4); And
And a step 1-5 of repeating the steps 1-3 and 1-4 until the gains for all the nodes are set. The method according to claim 1, .
11. The method of claim 10,
The pressure set in the step 1-1 is calculated by the following equation (2)
Wherein the average output value in the step 1-2 is calculated by the following equation (3): < EMI ID = 3.0 >
&Quot; (2) "
FORCE_BALANCING = {(P_MAX * A_SENSOR) + (P_MIN * A_SENSOR)} / 2
&Quot; (3) "
AVERAGE_NONZERO = SUM_NONZERO / N_NONZERO
In the above equation (2), P_MAX is the maximum detectable pressure of the sensor, A_SENSOR is the area of the sensor detection area, P_MIN is the minimum detectable pressure of the sensor,
In Equation (3), SUM_NONZERO is the sum of the detection values of nodes whose output value is not 0, and N_NONZERO is the number of nodes whose output value is not zero.
12. The method of claim 11,
Wherein the node gain calculated in the step 1-4 is calculated by the following equation (4): < EMI ID = 3.0 >
&Quot; (4) "
G_ij = AVERAGE_NONZERO / A_ij
Herein, AVERAGE_NONZERO is an average value obtained through Equation (3), and A_ij is a digital output value of a node corresponding to the intersection of the i-th driving electrode and the j-th detection electrode.
13. The method of claim 12,
The method for fine adjustment in the second step comprises:
A second step of setting the number N of fine adjustment points, setting each of the forces F_i corresponding to individual fine adjustment points, and setting i to 1;
Step 2-2 of applying a force F_i and obtaining an output value ADC0_pq of the individual node corresponding thereto (p is the index of the driving electrode and q is the index of the detecting electrode);
A second step of calculating an output value ADC_pq whose gain is adjusted by multiplying the output ADC0_pq of each node by the individual node gain G_pq;
Calculating ADC_SUM_i which is a sum of the adjusted output value ADC_pq and storing the result;
i is incremented by 1, i is determined to be greater than the number N of fine adjustment points, and if i is not greater than N, step 2-2 is performed;
(i) is greater than N, j is set to 1, and the equation of the curve function Y_j corresponding to ADC_SUM_j, F_j and ADC_SUM_ (j + 1), F_ Step 6; And
j is incremented by 1, j is determined to be greater than N-1, and if j is not greater than N-1, the process proceeds to step 2-6; otherwise, And converting the measured values of the digital output values into digital values.
14. The method of claim 13,
In the third step,
A 3-1 step of setting the index p of the P drive electrodes to 1 and setting the index q of the Q detection electrodes to 1;
a third step (2-2) of detecting an output value ADC0 (p, q) of a node corresponding to an intersection of the p-th driving electrode and the q-th detecting electrode;
A third step of calculating an output value ADC (p, q) whose gain is adjusted by multiplying the output value ADC0 (p, q) of the individual node by the gain G (p, q) of the individual node;
(P, q), and calculating a pressure physical quantity using the curve function of the section to which the ADC (p, q) belongs;
if it is determined that circulation of all driving electrodes is completed, if p is not equal to P, it is determined that circulation of all driving electrodes is completed; otherwise, p is increased by 1 and step S3-2 is performed; And
If p and P are equal to each other, it is determined whether q and Q are the same. If they are the same, it is determined that circulation is completed for all detection electrodes and the process ends. Otherwise, q is incremented by 1, The method according to any one of claims 1 to 3, further comprising:
15. The method of claim 14,
In the step 3-4,
And the pressure physical quantity is calculated by using a curve function as the following equation (5): < EMI ID = 6.0 >
&Quot; (5) "
P (p, q) = Y_i {ADC (p, q)}
Here, P (p, q) is a physical pressure value of a node corresponding to the p-th driving electrode 101 and the q-th detecting electrode 102, i is an index of a section to which ADC (p, q) belongs, is a function of a curve corresponding to the section to which (p, q) belongs.

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