WO2019080764A1

WO2019080764A1 - Sensing method of sensor, electronic apparatus, storage medium and terminal device

Info

Publication number: WO2019080764A1
Application number: PCT/CN2018/110762
Authority: WO
Inventors: 李扬渊; 张贺
Original assignee: 苏州迈瑞微电子有限公司
Priority date: 2017-10-24
Filing date: 2018-10-18
Publication date: 2019-05-02
Also published as: CN109697398B; CN109697398A

Abstract

A sensing method of a sensor, an electronic apparatus, a storage medium and a terminal device. Each sensor unit of a sensor satisfies y＝k/(ax+b), where x is an input value of each of the sensor units, and y is an output value of each of the sensor units. Acquiring an unknown input value of each of the sensor units comprises: enabling each of the sensor units to sense a known input value, and acquiring a first output value of each of the sensor units; enabling each of the sensor units to sense an unknown input value, and acquiring a second output value of each of the sensor units; and for each of the sensor units, calculating the unknown input value of each of the sensor units according to the following formula: unknown input value = (a/k)*(1/second output value - 1/first output value)+known input value.

Description

Sensor sensing method, electronic device, storage medium and terminal device

The present disclosure claims the priority of the Chinese Patent Application, filed on Jan.

Technical field

The present disclosure relates to the field of sensor technologies, for example, to a sensor sensing method, an electronic device, a storage medium, and a terminal device.

Background technique

The sensing equation of the CQT sensor circuit proposed by the patent CN105046194A satisfies T=Qr/(Cf*V+Qb), where Cf is the input value and T is the output value. For a single sensor unit, V, Qb and Qr are characteristic constants. . There is no method in the related art for acquiring an unknown input value for a sensor whose input and output are in a reciprocal relationship.

The input and output relationship of the traditional sensor is linear, that is, y=kx+b is satisfied, where x is the input value and y is the output value. If the input-output relationship cannot satisfy the linear relationship (ie, nonlinear), the traditional acquisition of the unknown input The value of the method is: the function of the output compensation, so that the input and output are close to a linear relationship, and then use the linear relationship of the sensing equation to obtain the input value, the method is very complicated.

Therefore, for a sensor whose input-output relationship satisfies y=k/(ax+b), it is necessary to provide a simple sensing method.

Summary of the invention

The present disclosure provides a sensor sensing method, an electronic device, a storage medium, and a terminal device to propose a sensing method for a sensor whose input-output relationship satisfies y=k/(ax+b), which is simple and easy.

The present disclosure provides a sensor sensing method, the sensor comprising at least one sensor unit, each sensor unit satisfying y=k/(ax+b), wherein x is an input value of each sensor unit, y is The output values of each of the sensor units, k, a, and b are characteristic constants of each of the sensor units, the method comprising: acquiring an unknown input value of each of the sensor units, wherein the obtaining the The unknown input value of each sensor unit includes: causing each of the sensor units to sense a known input value of each of the sensor units, obtaining a first output value of each of the sensor units; causing each of the sensors The unit senses an unknown input value of each of the sensor units, and acquires a second output value of each of the sensor units; for each of the sensor units, an unknown input value of each of the sensor units is calculated according to a calculation formula, The calculation formula is: the unknown input value of each sensor unit = (a / k) * (1/ the second output value of each sensor unit - 1 / the first output value of each sensor unit) + known input values for each sensor unit.

In an embodiment, the sensor is a fingerprint sensor, the fingerprint sensor includes a plurality of fingerprint sensor units and an integration circuit, and the input value x is a capacitance value Cf of the target capacitance sensed by each of the fingerprint sensor units, The output value y is the time T required to transfer the fixed amount of electricity between the integral capacitance of the integration circuit and the target capacitance, and Cf and T satisfy: T=Qr/(Cf*V+Qb) for each of the fingerprint sensors The units, Qr, V and Qb are characteristic constants.

The present disclosure provides a sensing method for a sensor whose input and output relationships are in a reciprocal relationship, which is simple and easy.

DRAWINGS

FIG. 1 is a flow chart of a sensor sensing method according to an embodiment.

FIG. 2 is a schematic diagram showing the circuit structure of a “C-Q-T” type fingerprint sensor according to an embodiment.

FIG. 3 is a schematic structural diagram of an electronic device according to an embodiment.

FIG. 4 is a schematic structural diagram of a terminal device according to an embodiment.

Detailed ways

The present disclosure will be described below in conjunction with the accompanying drawings and embodiments. The specific embodiments described herein are merely illustrative of the disclosure and are not intended to be limiting. In addition, for the convenience of description, only some but not all of the structures related to the present disclosure are shown in the drawings.

FIG. 1 is a flow chart of a sensor sensing method according to an embodiment.

The present disclosure relates to a sensing method of a sensor, the sensor comprising at least one sensor unit, each sensor unit satisfying y=k/(ax+b), where x is an input value of each of the sensor units, y For the output values of each of the sensor units, k, a, and b are characteristic constants of each sensor unit. In an embodiment, where the sensor comprises a plurality of sensor units, the characteristic constants of the plurality of sensor units may be different.

Referring to Figure 1, the sensor sensing process includes the following steps.

Step 110: Sense each sensor unit to sense a known input value of each sensor unit, and obtain a first output value of each sensor unit.

For each sensor unit, the first output value of each sensor unit and the known input value of each of the sensor units satisfy:

a*known input value +b=k/first output value (1)

In an embodiment, the known input values of the different sensor units are the same or different. In an example embodiment, the known input values of the different sensor units are the same and are zero.

Step 120: Sense each of the sensor units to sense an unknown input value of each sensor unit, and obtain a second output value of each sensor unit.

For each sensor unit, the unknown input value of each sensor unit and the second output value of each of the sensor units satisfy:

a*Unknown input value +b=k/second output value (2)

Step 130: For each sensor unit, calculate an unknown input value of the sensor unit according to a calculation formula.

In an embodiment, the formula is:

The unknown input value of each sensor unit = (a / k) * (1/ the second output value - 1 / the first output value) + the known input value (3)

In an embodiment, the sensing method is applicable to a “C-Q-T” type fingerprint sensor. The fingerprint sensor in this embodiment can apply the “C-Q-T” type fingerprint sensor circuit (hereinafter referred to as Patent 1) in the patent CN105046194A. 2 is a circuit diagram of the fingerprint sensor. Referring to FIG. 2, the fingerprint sensor includes a fingerprint sensor unit array 1, and the fingerprint sensor unit array 1 includes at least one fingerprint sensor unit 11. Each fingerprint sensor unit 11 includes a target electrode 111, a sensing electrode 112, a driving electrode 113, a first level driver 114, a second level driver 115, an initialization switch 116, a row selection switch 117, and a first reference voltage 118. The fingerprint sensor further includes an integrator 2 connected to at least one fingerprint sensor unit 11 and a comparator module 3 connected to the integrator 2. The integrator 2 includes an integrating capacitor 21, an amplifier 22, a first reset switch 23, a second reset switch 24, a follow switch 25, and a second reference voltage 26 and a third reference voltage 27. The comparator module 3 includes a comparator 32 and a fourth reference voltage 31. Each fingerprint sensor unit 11 senses the magnitude of the target capacitance, and the output value is the time when the output of the comparator 32 is inverted. For details, refer to Patent 1, that is, the input value is the capacitance value of the sensed target capacitance, and the output value is a time value. .

According to the principle of charge balance and the working principle of the integrator, the amount of charge ΔQ that the integrating capacitor 21 discharges to the target capacitor each time can be obtained:

ΔQ=(ΔVREF-ΔV1)*Cf+(ΔVREF-ΔV2)*Cd+ΔVREF*Cb (4)

Where Cf is the target capacitance, Cd is the drive capacitance, Cb is the background capacitance, and ΔVREF, ΔV1, ΔV2 are the voltages set by the system (refer to Patent 1).

The output of the fingerprint sensor unit is the amount of time T, and the formula for calculating T is:

T=(Qr.end-Qr.rst)/ΔQ (5)

Wherein, Qr.end is the charge amount of the integral capacitor at the time when the comparator 32 outputs the inversion, Qr.rst is the charge amount of the integral capacitor after the reset of the integrator 2, and Qr.end-Qr.rst is the integral of the inverter 32 when the output is inverted. The discharge amount of the capacitor 21, Qr.end-Qr.rst is a constant amount of electric power released by the integral capacitor 21 of the integrating circuit 2 to the target capacitor, and the amount of time T is that the integral capacitor 21 of the integrating circuit 2 releases the rated amount of electricity to the target capacitor. The time required.

Let V = ΔVREF - ΔV1, Qb = (ΔVREF - ΔV2) * Cd + ΔVREF * Cb, Qr = Qr. end - Qr. rst, for a single sensor unit, Qr, V and Qb are characteristic constants, where Qr and V It is known, and the Qb value is more difficult to obtain.

Combine equations (4) and (5):

T=Qr/(Cf*V+Qb) (6)

It can be seen from equation (6) that the capacitance value C of T and the target capacitance is a reciprocal relationship.

Then push back the formula (6), then there is

V*Cf+Qb=Qr/T (7)

The following is the sensing process of the fingerprint sensor:

First, when the input Cf0 is known, the time T0 output by each fingerprint sensor unit is read out, and at this time, the target capacitance Cf0 sensed by each fingerprint sensor unit satisfies:

V*Cf0+Qb=Qr/T0 (8)

In an embodiment, the known inputs Cf0 of the different fingerprint sensor units 11 are the same or different. In an embodiment, the known inputs Cf0 of the different fingerprint sensor units 11 are identical and zero, i.e., there is no sensing target.

In one embodiment, the step is performed prior to shipment of the electronic device on which the fingerprint sensor is installed, i.e., only the time output value of each fingerprint sensor unit at a known input is required to be acquired.

Then, when the input is unknown, the time T1 output by each fingerprint sensor unit 11 is read out, wherein the unknown input may indicate the target capacitance Cf1 sensed by the fingerprint sensor unit when there is a detection target such as a fingerprint on the sensing surface of the fingerprint sensor. For each fingerprint sensor unit, the sensed target capacitance Cf1 satisfies:

V*Cf1+Qb=Qr/T1 (9)

Finally, the target capacitance Cf1 is calculated according to time T1, time T0 and known input Cf0, and Cf1 is satisfied:

Cf1=(Qr/V)*(1/T1-1/T0)+Cf0 (10)

The target capacitance Cf1 acquired by the plurality of fingerprint sensor units constitutes a fingerprint image.

In order to eliminate the background capacitance and the driving capacitance, it is necessary to set ΔVREF=ΔV2=0, and in the final calculation formula (10), the background capacitance and the driving capacitance (corresponding to the Qb value) are offset, so there is no need to set ΔVREF = ΔV2 = 0, thereby reducing the limitations on circuit design.

FIG. 3 is a schematic structural diagram of an electronic device according to an embodiment. The electronic device comprises a sensor 10 comprising at least one sensor unit 110, each sensor unit 110 satisfying y=k/(ax+b), where x is the input value of each of the sensor units 11, y For the output values of each of the sensor units 11, k, a, and b are characteristic constants of each of the sensor units 11, the electronic device further includes: an output acquisition unit 20 connected to the sensor 10, and the The control unit 30 to which the sensor 10 is connected and the solving unit 40 connected to the output acquisition unit 20 are provided.

In an embodiment, the control unit 30 is arranged to control each sensor unit 11 to sense a known input value of each of the sensor units 11, and the output acquisition unit 20 is arranged to acquire a first output of each of the sensor units 11. a value; the control unit is further configured to control the each sensor unit 11 to sense an unknown input value of each of the sensor units 11, and the output acquisition unit 20 is further configured to acquire a second output of each of the sensor units 11 The solution unit 40 is configured to solve the unknown input value of each of the sensor units 11 according to the solution formula, and the solution formula is: the unknown input value of each sensor unit 11=(a/k)*( 1/ The second output value of each sensor unit 11 - 1 / the first output value of each sensor unit 11 ) + the known input value of each of the sensor units 11 .

In an embodiment, the known input values are the same or different for different sensor units 11. In an embodiment, for different sensor units 11, the known input values are the same and zero.

In an embodiment, the electronic device is suitable for a fingerprint sensor, the sensor 10 is a fingerprint sensor, the fingerprint sensor comprises a plurality of fingerprint sensor units 11 and an integration circuit 2, and the input value x is the fingerprint sensor unit 11 sensing The capacitance value Cf of the target capacitance, which is the time T required to transfer the constant amount of electricity between the integrating capacitor 21 of the integrating circuit 2 and the target capacitance, and Cf and T satisfy: T=Qr/(Cf*V+ Qb), for a single fingerprint sensor unit 11, the Qr, V and Qb are characteristic constants.

The present disclosure also provides a computer readable storage medium having stored thereon a computer program executed by a processor to perform the sensor sensing method of any of the above embodiments.

FIG. 4 is a schematic structural diagram of a terminal device according to an embodiment. Referring to FIG. 4, the terminal device provided in this embodiment includes a memory 100, a processor 200, and a computer program stored on the memory 100 and operable on the processor 200, and the processor 200 executes the computer program to implement any of the foregoing embodiments. Sensor sensing method. The terminal device may be a sensor device, such as a fingerprint sensor, or a terminal integrated with a fingerprint sensor, such as a mobile terminal.

The above are only the embodiments of the present disclosure and the technical principles applied thereto.

Claims

A sensor sensing method, the sensor comprising at least one sensor unit, each sensor unit satisfying y=k/(ax+b), wherein x is an input value of each of the sensor units, and y is the each The output values of the sensor units, k, a, and b are characteristic constants of each of the sensor units, the method comprising: acquiring an unknown input value of each of the sensor units, wherein the acquiring each of the sensor units Unknown input values include:

Having each of the sensor units sense a known input value of each of the sensor units to obtain a first output value of each of the sensor units;

Having the each sensor unit sense an unknown input value of each of the sensor units to obtain a second output value of each of the sensor units;

For each of the sensor units, an unknown input value of each sensor unit is calculated according to a calculation formula, wherein the calculation formula is: an unknown input value of each sensor unit=(a/k)*(1) / The second output value of each sensor unit - 1 / the first output value of each sensor unit) + the known input value of each of the sensor units.
The sensor sensing method according to claim 1, wherein in the case where the at least one sensor unit includes a plurality of sensor units, known input values of the plurality of sensor units are the same or different.
The sensor sensing method according to claim 1, wherein in the case where the at least one sensor unit includes a plurality of sensor units, the known input values of the plurality of sensor units are the same and are zero.
The sensor sensing method according to any one of claims 1 to 3, wherein the sensor is a fingerprint sensor, the fingerprint sensor includes a plurality of fingerprint sensor units and an integration circuit, and the input value x is each fingerprint sensor a capacitance value Cf of the target capacitance sensed by the unit, the output value y being a time T required to transfer a constant amount of electricity between the integral capacitance of the integration circuit and the target capacitance, and the Cf and the T satisfy: T = Qr / (Cf * V + Qb), for each of the fingerprint sensor units, Qr, V and Qb are characteristic constants.
An electronic device comprising a sensor, the sensor comprising at least one sensor unit, each sensor unit satisfying y=k/(ax+b), wherein the x is an input value of each of the sensor units The y is an output value of each of the sensor units, k, a, and b are characteristic constants of each of the sensor units, and the electronic device further includes: an output acquisition unit connected to the sensor, and a control unit connected to the sensor and a resolving unit connected to the output obtaining unit, wherein the control unit is configured to control the each sensor unit to sense a known input value of each of the sensor units, the output The obtaining unit is configured to acquire a first output value of each of the sensor units;

The control unit is further configured to control the each sensor unit to sense an unknown input value of each of the sensor units, and the output obtaining unit is further configured to acquire a second output value of each of the sensor units;

The solving unit is configured to solve an unknown input value of each sensor unit according to a solution formula, wherein the solution formula is: an unknown input value of each sensor unit=(a/k)* (1/the second output value of each sensor unit - 1 / the first output value of each sensor unit) + the known input value of each of the sensor units.
The electronic device according to claim 5, wherein in the case where the at least one sensor unit includes a plurality of sensor units, the known input values of the plurality of sensor units are the same or different.
The electronic device according to claim 5, wherein in the case where the at least one sensor unit includes a plurality of sensor units, the known input values of the plurality of sensor units are the same and are zero.
The electronic device according to any one of claims 5 to 7, wherein the sensor is a fingerprint sensor, the fingerprint sensor includes a plurality of fingerprint sensor units and an integration circuit, and the input value x is a sense of each fingerprint sensor unit a measured capacitance value Cf of the target capacitance, the output value y being a time T required to transfer a fixed amount of electricity between the integral capacitance of the integrating circuit and the target capacitance, and the Cf and the T satisfy: T= Qr / (Cf * V + Qb), for each of the fingerprint sensor units, Qr, V and Qb are characteristic constants.
A computer readable storage medium storing a computer program, the computer program being executed by a processor to implement the sensor sensing method according to any one of claims 1-4.
A terminal device comprising a memory, a processor, and a computer program stored on the memory and operable by the processor, the processor executing the computer program to implement any one of claims 1-4 The sensor sensing method described.