CN209281370U - Capacitance-type sensing device and electronic equipment - Google Patents

Abstract

The utility model discloses a kind of capacitance-type sensing device and electronic equipments.The capacitance-type sensing device includes sensor unit, modulation unit and detection unit.The sensor unit includes a plurality of first electrode and a plurality of second electrode, and a plurality of first electrode and a plurality of second electrode insulate cross arrangement.The modulation unit is for generating modulated signal.The detection unit is for receiving the modulated signal, and by provide pumping signal to a plurality of second electrode, the control a plurality of first electrode is successively hanging and provides a scheduled reference voltage signal and gives not hanging first electrode, to drive the sensor unit to execute sensing operation.The electronic equipment includes above-mentioned capacitance-type sensing device.

Description

Capacitive sensing device and electronic equipment

technical field

The utility model relates to the field of biological identification, in particular to a capacitive sensing device and electronic equipment.

Background technique

Currently, capacitive sensing devices are widely used, for example, capacitive sensing devices are used in fields such as touch detection and fingerprint recognition. However, the cost of capacitive sensing devices is still high.

Utility model content

The embodiments of the utility model aim at at least solving one of the technical problems existing in the prior art. Therefore, the embodiment of the present utility model needs to provide a capacitive sensing device and electronic equipment.

The utility model provides a capacitive sensing device, comprising:

The sensor unit includes a plurality of first electrodes and a plurality of second electrodes, and the plurality of first electrodes and the plurality of second electrodes are insulated and cross-arranged;

a modulation unit for generating a modulation signal; and

The detection unit is configured to receive the modulation signal, and provide an excitation signal to the plurality of second electrodes, control the plurality of first electrodes to be suspended in sequence, and provide a predetermined reference voltage signal to the first electrodes that are not suspended in the air. an electrode to drive the sensor unit to perform a sensing operation;

Wherein, the excitation signal is a signal modulated by the modulation signal.

In contrast, the existing capacitive sensing device includes a plurality of rectangular block electrodes, the plurality of rectangular block electrodes are coplanar on the same layer, spaced from each other, and arranged in a matrix, and each rectangular block electrode is connected by a wire to the detection circuit. Wherein, each block electrode corresponds to a sensing pixel.

It can be seen from the comparison that since the capacitive sensing device of the present application includes the plurality of first electrodes and the plurality of second electrodes, and the plurality of first electrodes and the plurality of second electrodes are insulated from each other , and each intersection corresponds to a sensing pixel. Therefore, compared with the above-mentioned existing capacitive sensing device, the capacitive sensing device of the present application ensures that there are enough sensing pixels. The number of wires connecting the plurality of first electrodes and the plurality of second electrodes to the detection unit is reduced, thereby reducing the cost of the capacitive sensing device.

In addition, the miniaturization of the capacitive sensing device can also be facilitated due to the reduction in the number of wires.

Further, since the excitation signal is a signal modulated by the modulating signal, the signal-to-noise ratio of the capacitive sensing device can be improved, thereby improving the sensing accuracy of the capacitive sensing device.

In some embodiments, the detection unit further receives a sensing signal output from the second electrode to obtain sensing information.

In some embodiments, the predetermined reference voltage signal is a constant voltage signal, or, the predetermined reference voltage signal is a constant voltage signal modulated by the modulating signal.

In some embodiments, the sensor unit further includes an insulating substrate and an insulating layer, the plurality of second electrodes are disposed on the insulating substrate, and the insulating layer is disposed on the plurality of second electrodes, so The plurality of first electrodes are disposed on the insulating layer.

Since the sensor unit of the present invention uses an insulating substrate to make the first electrode and the second electrode, the manufacturing cost of the capacitive sensing device of the present invention is further reduced compared with the sensor unit in which the sensing electrodes are made on the silicon substrate. .

In some embodiments, the sensor unit further includes a protective layer disposed on the second electrode.

In some embodiments, the plurality of first electrodes are arranged in parallel, the plurality of second electrodes are arranged in parallel, and the plurality of first electrodes and the plurality of second electrodes are vertically intersected.

In some embodiments, the modulation unit is integrated in a control chip, the detection unit is integrated in a sensing chip, and the control chip and the sensing chip are arranged on the insulating substrate.

In some embodiments, the modulation unit is integrated in a control chip, the detection unit is integrated in a sensing chip, and the control chip and the sensing chip are arranged on the insulating substrate; the The capacitive sensing device also includes a package, which is used to cover the sensor unit, the sensing chip, and the control chip, and to fill the space between the sensor unit, the sensing chip, and the control chip. Clearance.

In some embodiments, the plurality of first electrodes are used to capacitively couple to a target object, and the capacitive sensing device is used to sense whether there is a touch of the target object, and/or, to sense Biometric information of the target object.

In some embodiments, the suspended first electrodes are used to form a first coupling capacitance with the target object, and the intersections between the plurality of first electrodes and the plurality of second electrodes form a second coupling A capacitor, the first coupling capacitor and the second coupling capacitor are connected in series between the detection unit and the ground.

In some embodiments, the first electrode to which the predetermined reference voltage is applied is used as a shielding electrode.

In some embodiments, the detection unit makes the first electrode suspended by disconnecting the connection with the first electrode. When the detection unit disconnects the connection with a first electrode, it The disconnected first electrodes are electrically reconnected.

In some embodiments, the signals in the detection unit are all signals modulated by the modulation signal.

Correspondingly, the signals on the plurality of first electrodes and the plurality of second electrodes are all signals modulated by the modulation signal, so that the lateral parasitic capacitance and phase between adjacent first electrodes can be reduced. Adverse influences such as lateral parasitic capacitance between adjacent second electrodes. In addition, the signal-to-noise ratio of the excitation signal can also be provided, thereby improving the signal-to-noise ratio of the sensing signal, thereby further improving the sensing accuracy of the capacitive sensing device.

In some embodiments, the detection unit further includes a ground terminal, and the modulation unit is configured to output the modulated signal to the ground terminal as a ground signal of the detection unit.

In some embodiments, the detection unit includes a reference circuit, a plurality of first switches, and a control circuit, the reference circuit is correspondingly connected to the plurality of first electrodes through the plurality of first switches, the The reference circuit is used to provide the predetermined reference voltage, the control circuit is connected to the plurality of first switches, and is used to control the plurality of first switches to open or close.

In some implementations, the detection circuit controls the plurality of first switches to be turned off sequentially through the control circuit, so as to control the plurality of first electrodes to be suspended in sequence.

In some embodiments, after the control circuit controls the first switch to be turned off for a predetermined time, the first switch that is currently turned off is closed, and another closed first switch is turned off.

In some embodiments, when the control circuit controls one of the plurality of first switches to be turned off, the other first switches are controlled to be turned on.

In some embodiments, the detection unit further includes a signal reading circuit, the signal reading circuit is used to connect with the plurality of second electrodes, provide an excitation signal to the second electrodes, and receive the second electrodes. Sensing signals output by the electrodes to obtain sensing information.

In some embodiments, the detection unit further includes a plurality of second switches and a plurality of signal reading circuits, the plurality of second switches are connected to the plurality of second electrodes in a one-to-one correspondence, the The control circuit is connected to the plurality of second switches, and is used to control the plurality of second switches to open or close, and the number of the plurality of signal reading circuits is less than the number of the plurality of second switches .

In some embodiments, at least part or all of the signal reading circuits are respectively connected to at least two of the second switches, and when the detection unit is sequentially disconnected from multiple first electrodes, the at least part or all The signal reading circuit is used to electrically connect with the plurality of second electrodes in time division.

In some embodiments, the signal reading circuit includes an amplifier and a feedback branch, wherein the amplifier includes a non-inverting terminal, an inverting terminal, and an output terminal, and the feedback branch is connected between the inverting terminal and the Between the output terminals, the inverting terminal is further connected to the second electrode through a second switch, and the non-inverting terminal is used for receiving the excitation signal.

In some implementations, the amplifier further includes a ground terminal for receiving the modulation signal.

In some embodiments, the capacitive sensing device is one or more of a touch sensing device and a biological information sensing device.

In some embodiments, the capacitive sensing device is a fingerprint sensing device.

The utility model provides an electronic device, which includes the capacitive sensing device in any one of the above-mentioned embodiments.

In some embodiments, the electronic device includes any one or more of mobile terminals, smart home products, vehicle electronic products, and wearable electronic products.

In some embodiments, the electronic device includes a display area and a non-display area, and the capacitive sensing device is located in the display area or in the non-display area.

In some embodiments, when the capacitive sensing device is located in the non-display area, the capacitive sensing device is a biological information sensing module.

In some implementations, when the capacitive sensing device is located in the display area, a partial area or the entire area of the display area of the electronic device can be used to perform biometric information sensing.

In some embodiments, the capacitive sensing device is used to perform touch sensing, and a part of the area is further used to perform biometric information sensing.

Since the electronic equipment includes the capacitive sensing device, the cost of the electronic equipment is correspondingly reduced, and the sensing performance is better.

Additional aspects and advantages of embodiments of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of embodiments of the invention.

Description of drawings

The above and/or additional aspects and advantages of the embodiments of the present utility model will become apparent and easy to understand from the description of the embodiments in conjunction with the following drawings, wherein:

Fig. 1 is the structural representation of existing a kind of capacitive sensing device;

Fig. 2 is the circuit block diagram of the capacitive sensing device of the utility model embodiment;

Fig. 3 is a schematic structural view of an embodiment of the sensor unit in Fig. 2;

Fig. 4 is a schematic structural view of another embodiment of the sensor unit in Fig. 2;

5 is a schematic cross-sectional view of a capacitive sensing device according to an embodiment of the present invention;

6 is a schematic diagram of the connection structure between the first electrode and the second electrode, the detection unit and the modulation unit in the capacitive sensing device according to the embodiment of the present invention;

7 is a schematic diagram of the connection structure of the first electrode and the second electrode corresponding to the reference circuit and the signal reading circuit in the capacitive sensing device according to the embodiment of the present invention;

8 is a schematic diagram of an equivalent circuit of a capacitive sensing device performing capacitive sensing according to an embodiment of the present invention;

FIG. 9 is a schematic plan view of an electronic device according to an embodiment of the present invention.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present utility model, but should not be construed as limiting the present utility model.

In the description of the present utility model, it should be understood that the terms "first" and "second" are only used for descriptive purposes, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the number of indicated technical features . Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of said features. In the description of the present utility model, "plurality" means two or more, unless otherwise specifically defined.

In the description of the present utility model, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a flexible connection. Detachable connection, or integral connection; it can be mechanical connection, electrical connection or mutual communication; it can be directly connected or indirectly connected through an intermediary, and it can be the internal communication of two components or the mutual communication of two components role relationship. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present utility model according to specific situations.

The disclosure below provides many different implementations or examples for realizing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the utility model. Furthermore, the present invention may repeat reference numerals and/or reference letters in different instances, such repetition is for the purpose of simplicity and clarity, and does not in itself indicate a relationship between the various embodiments and/or arrangements discussed. In addition, various specific process and material examples are provided herein, but one of ordinary skill in the art may recognize the use of other processes and/or the use of other materials.

Furthermore, the described features and structures may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided in order to give a thorough understanding of embodiments of the invention. However, those skilled in the art should appreciate that the technical solutions of the present invention can also be practiced without one or more of the specific details, or with other structures, components, and the like. In other instances, well-known structures or operations are not shown or described in detail to avoid obscuring the invention.

Please refer to FIG. 1 . FIG. 1 is a schematic structural diagram of a conventional capacitive sensing device. The capacitive sensing device 100 includes a substrate 10 , a plurality of sensing electrodes 12 , and a detection circuit 16 . The plurality of sensing electrodes 12 are formed on the substrate 10 , and the plurality of sensing electrodes 12 are arranged in a two-dimensional array, that is, a sensing array 14 is formed. The plurality of sensing electrodes 12 are coplanar in the same layer, and each sensing electrode 12 forms a sensing pixel point. The detection circuit 16 is formed on the substrate 10 and located at the periphery of the sensing array 14 . The detection circuit 16 is electrically connected to each sensing electrode 12 for providing an excitation signal to each sensing electrode 12 to drive each sensing electrode 12 to perform a sensing operation. Further, the detection circuit 16 receives the sensing signal output from the sensing electrode 12, and obtains sensing information according to the sensing signal.

The capacitive sensing device 100 may, for example but not limited to, perform touch detection, and/or perform biometric information detection, for example, the capacitive sensing device 100 is used to detect biometrics such as fingerprints, palm prints, and ear prints. texture information. The organism is, for example, a human body but is not limited to a human body, and may also be other suitable organisms.

However, since the detection circuit 16 is electrically connected to each sensing electrode 12, for example, through wires, if the number of sensing electrodes 12 is large, it will be more difficult to arrange the wires, thereby increasing the capacitance. The manufacturing cost of the type sensor device 100. In addition, in order to meet the electrical requirements, there must be a certain interval between the wires, so the more wires are arranged, the larger the size of the capacitive sensing device 100 is to ensure the yield of the capacitive sensing device 100, thereby It is not conducive to the miniaturization development of the capacitive sensing device 100 .

Especially, when the capacitive sensing device 100 is, for example, a small-sized biological information sensing module, the above-mentioned technical problems are more prominent. Generally, the small-sized biometric information sensing module is arranged, for example, in a non-display area of the mobile terminal, for example, at the position of the Home button, on the back and side of the mobile terminal, and so on. However, alternatively, the biometric information sensing module can also be set in, for example, the display area of the mobile terminal. Wherein, the display area is an area where the mobile terminal displays images.

In order to solve at least one of the above technical problems, the utility model proposes a new capacitive sensing device 200 . Please refer to FIG. 2 and FIG. 3 together. FIG. 2 is a circuit block diagram of the capacitive sensing device 200 of the present invention, and FIG. 3 is a structural schematic diagram of an embodiment of the sensor unit of the capacitive sensing device 200 shown in FIG. 2 . The capacitive sensing device 200 can be used to perform any one or several functions of biological information sensing, touch sensing, and the like. The capacitive sensing device 200 includes a sensor unit 22 , a detection unit 24 , and a modulation unit 26 .

The sensor unit 22 includes a plurality of first electrodes 222 and a plurality of second electrodes 224 . The plurality of first electrodes 222 and the plurality of second electrodes 224 are insulated and cross-arranged.

The modulating unit 26 is used for generating a modulating signal M.

The detection unit 24 is used for receiving the modulation signal M, and by providing an excitation signal Vref to the plurality of second electrodes 224, sequentially controlling the plurality of first electrodes 222 to be suspended, and providing a predetermined reference voltage signal Vp is given to the first electrode 222 which is not suspended to drive the sensor unit 22 to perform a sensing operation.

Wherein, the excitation signal Vref is a signal modulated by the modulation signal M.

Since the capacitive sensing device 200 of the present application includes the plurality of first electrodes 222 and the plurality of second electrodes 224, and the plurality of first electrodes 222 and the plurality of second electrodes 224 are insulated from each other, Each intersection corresponds to a sensing pixel. Therefore, compared with the above-mentioned existing capacitive sensing device, the capacitive sensing device of the present application ensures that there are enough sensing pixels. The number of wires connecting the plurality of first electrodes 222 and the plurality of second electrodes 224 to the detection unit 24 is reduced, thereby reducing the cost of the capacitive sensing device 200 .

Further, the miniaturization of the capacitive sensing device 200 can also be facilitated due to the reduction in the number of wires.

In addition, since the excitation signal Vref is a signal modulated by the modulation signal M, the signal-to-noise ratio of the capacitive sensing device 200 can be improved, thereby improving the sensing performance of the capacitive sensing device 200. precision.

In some implementations, the excitation signal Vref varies with the modulation signal M. For example, the excitation signal Vref increases as the modulation signal M increases, and decreases as the modulation signal M decreases.

The detection unit 24 further receives the sensing signal Vd output from the second electrode 224 to obtain sensing information. The predetermined reference voltage signal Vp is, for example, a signal modulated by the modulation signal M.

The plurality of first electrodes 222 are used to capacitively couple to a target object. The capacitive sensing device 200 is used for sensing whether there is a touch of the target object, and/or sensing biometric information of the target object. The biometric information is, for example, fingerprint information, palmprint information, earprint information, and other suitable texture information on a living body. The target object corresponds to, for example, a finger, a palm, an ear, and the like.

The detection unit 24 makes the first electrode 222 suspended in the air by disconnecting the connection with the first electrode 222 . When the detection unit 24 is disconnected from a first electrode 222 , it is electrically reconnected to the previously disconnected first electrode 222 .

In some implementations, the plurality of first electrodes 222 are arranged at intervals along the first direction, and each first electrode 222 extends along the second direction. The plurality of second electrodes 224 are arranged at intervals along the second direction, and each second electrode 224 extends along the first direction. The first direction is different from the second direction. The first direction and the second direction are for example but not limited to a vertical relationship. As shown in FIG. 3 , in this embodiment, the first electrodes 222 are used as row electrodes and arranged sequentially in the Y direction, that is, the first row, the second row, the third row...the mth row, where m is A natural number greater than 1. The second electrodes 224 serve as column electrodes and are arranged sequentially in the X direction, that is, the first column, the second column, the third column...the nth column, wherein n is a natural number greater than 1. The intersecting regions between the plurality of first electrodes 222 and the plurality of second electrodes 224 form a second coupling capacitor CF, that is, the capacitive sensing device 200 can be formed with m*n second coupling capacitors CF (see FIG. 6). Alternatively, for example, the first direction and the second direction may also be set at a certain angle, such as 45°, 60° and so on. In this embodiment, the plurality of first electrodes 222 and the plurality of second electrodes 224 are in the shape of rectangular strips, however, alternatively, the plurality of first electrodes 222 and the plurality of second electrodes 224 may also be in other suitable shapes, such as curved strips and the like.

Please refer to FIG. 4 , which is a schematic structural diagram of another embodiment of the sensor unit 22 . The plurality of first electrodes 222 are arranged at intervals along the first direction, and each first electrode 222 includes a plurality of first sub-electrodes 222 a and wires 222 b connecting adjacent first sub-electrodes 222 a. A plurality of second electrodes 224 are arranged at intervals along the second direction, and each second electrode 224 includes a plurality of second sub-electrodes 224 a and wires 224 b connecting adjacent second sub-electrodes 224 a. The first direction and the second direction are different, such as but not limited to a vertical relationship. As shown in Figure 4, the first electrodes 222 are used as row electrodes, arranged in sequence in the Y direction, such as row 1, row 2, row 3 ... row 7; the second electrodes 224 are used as column electrodes, arranged in the direction X Arranged in order, such as column 1, column 2, column 3...column 8. The intersection area between the first electrode 222 and the second electrode 224 forms a second coupling capacitor CF (see FIG. 6 ), therefore, the sensor unit 22 shown in FIG. 4 can be formed with 7*8=56 second coupling capacitors CF . It should be noted that the number 56 here is just an example, and the number of actual products can be more or less than 56, and the manufacturer can set correspondingly according to product needs. Alternatively, the first direction and the second direction may also be set at a certain angle, such as 45°, 60°, etc., for example. In this embodiment, the first electrode 222 and the second electrode 224 are in the shape of a rectangular block, however, the application is not limited thereto, and the first electrode 222 and the second electrode 224 can also be in other suitable shapes . Compared with the first electrode 222 and the second electrode 224 shown in FIG. 3 , the lengths of the first electrode 222 and the second electrode 224 shown in FIG. 4 are shortened.

It can be understood that the structure of the first electrode 222 and the structure of the second electrode 224 in the above embodiments can be combined and deformed in various ways, as long as the first electrode 222 and the second electrode 224 are insulated and intersected.

The above-mentioned first electrode 222 and second electrode 224 can be made of, for example, a transparent conductive material, such as indium tin oxide (ITO) material, indium zinc oxide (IZO) material, and the like. However, alternatively, the first electrode 222 and the second electrode 224 may also be made of other suitable conductive materials, such as metal materials, alloy materials and so on. Since both the first electrode 222 and the second electrode 224 are conductive electrodes, an insulating material is provided between the first electrode 222 and the second electrode 224 for electrical isolation.

Please refer to FIG. 5 , which is a schematic cross-sectional view of a capacitive sensing device 200 of the present application. In some embodiments, the aforementioned sensor unit 22 may further include a substrate 220 and an insulating layer 226 . The multiple second electrodes 224 are disposed on the substrate 220 , the insulating layer 226 is disposed on the multiple second electrodes 224 , and the multiple first electrodes 222 are disposed on the insulating layer 226 . The area where the first electrode 222 and the second electrode 224 are located is defined as the sensing area I, and the area around the sensing area I on the substrate 220 is defined as the non-sensing area II. Optionally, the detection unit 24 and the modulation unit 26 are located in the non-sensing region II of the substrate 220 . However, alternatively, the detecting unit 24 and the modulating unit 26 may also be connected to the substrate 220 through connectors such as flexible circuit boards, and it is not limited that the detecting unit 24 and the modulating unit 26 are disposed on the substrate 220 .

The substrate 220 is an insulating substrate, such as a suitable type of substrate such as a glass substrate or a film substrate.

In some implementations, the detection unit 24 is integrated in a sensing chip, for example, through a silicon process, and the modulation unit 26 is integrated in a control chip, for example, through a silicon process. Of course, the detecting unit 24 and the modulating unit 26 are not limited to be integrated on one chip, but may also be integrated on several chips, such as two, three, etc., in consideration of appropriate circumstances. The sensing chip and the control chip are bonded on the substrate 220 by, for example, chip on glass (Chip On Glass, COG) or chip on film (Chip On Film, COF). The detecting unit 24 and the modulating unit 26 are further connected to an external circuit (not shown in the figure) through a suitable connector such as a flexible circuit board.

Since the sensor unit 22 of the present application forms the first electrode 222 and the second electrode 224 on the insulating substrate 220, compared with the sensor unit whose sensing electrodes are formed on the silicon substrate, the present application includes the sensor unit The manufacturing cost of the capacitive sensing device 200 of 22 is further reduced.

In some implementations, the modulation unit 26 outputs the modulation signal M to the ground terminal c (see FIG. 8 ) of the detection unit 24 as the ground signal of the detection unit 24 , for example. The ground signal corresponds to a changing signal. Correspondingly, the electrical signals of the detection unit 24 all use the changed ground signal as a voltage reference signal. When the ground signal changes, the electric signals in the detection unit 24 all change with the change of the ground signal. Therefore, all the signals of the detection unit 24 are signals modulated by the modulation signal M.

Alternatively, in other embodiments, the modulation unit 26 can also output the modulation signal M to the power supply terminal d (see FIG. 8 ) or the reference power supply terminal (not shown in the figure) of the detection unit 24, etc., and can also achieve the detection All signals in unit 24 are modulated to effect.

Since all the signals in the detection unit 24 are signals modulated by the modulation signal M, the signals on the plurality of first electrodes 222 and the plurality of second electrodes 224 are all signals modulated by the modulation signal M. The M-modulated signal can reduce adverse effects of lateral parasitic capacitance between adjacent first electrodes 222 , lateral parasitic capacitance between adjacent second electrodes 224 , and the like. In addition, the signal-to-noise ratio of the excitation signal Vref can be improved, thereby improving the signal-to-noise ratio of the sensing signal Vd, and further improving the sensing accuracy of the capacitive sensing device 200 .

Please refer to FIG. 5 again. In some embodiments, the sensor unit 22 may further include a protective layer 228 . The protection layer 228 is disposed on the plurality of first electrodes 222 and the insulating layer 266, so as to prevent the first electrodes 222 from being directly contacted with the outside and damaging the first electrodes 222, thus affecting the sensing effect. However, alternatively, in other embodiments, the protective layer 228 can also be omitted. In addition, for example, when the capacitive sensing device 200 is a biological information sensing module, the protective layer 228 can also be replaced by a package, and the sensor unit 22, the sensing chip and the control chip are packaged in the package body and the substrate 220. The package is used to cover the sensor unit 22 , the sensing chip and the control chip, and to fill the gap between the sensor unit 22 , the sensing chip and the control chip. The package is, for example but not limited to, made of materials such as epoxy resin.

Please refer to FIG. 5 and FIG. 6 together. FIG. 6 is a schematic diagram of the connection structure of the first electrode 222 and the second electrode 224 with the detection unit 24 and the modulation unit 26 . When a target object 400 touches the sensing region I of the capacitive sensing device 200 , a first coupling capacitor CS is formed between the target object 400 and the plurality of first electrodes 222 . In addition, a plurality of second coupling capacitors CF are formed between the plurality of first electrodes 222 and the plurality of second electrodes 224 . Wherein, the first coupling capacitor CS formed between the suspended first electrode 222 and the target object 400 is connected in series with the second coupling capacitor CF between the detection unit 24 and the ground. In contrast, the first electrode 222 that is not suspended in the air is used as a shielding electrode because it receives the predetermined reference voltage signal Vp. Correspondingly, the first coupling capacitance CS formed between the first electrode 222 that is not suspended in the air and the target object 400 is shielded and will not be detected by the detection unit 24. Therefore, the first coupling capacitance CS formed between the target object 400 and the suspended first electrode 222 is critical for the detection unit 24 to obtain sensing information, and can be detected by the detection unit 24 . In this embodiment, the target object is a finger 400 .

Generally, the human body is connected to the earth. Correspondingly, when the target object is, for example, the finger 400 of a human body, the first coupling capacitor CS and the second coupling capacitor CF are equivalent to being connected in series between the detection unit 24 and the ground.

It should be noted that, in this application, the word "contact" includes direct touch and proximity.

In some implementations, the detection unit 24 includes a reference circuit 240 , a plurality of first switches S1 , and a control circuit 242 . The reference circuit 240 is connected to the plurality of first electrodes 222 in a one-to-one correspondence through the plurality of first switches S1. The reference circuit 240 is used for providing the predetermined reference voltage signal Vp to the plurality of first electrodes 222 . The control circuit 242 is connected with the plurality of first switches S1, and is used for controlling the plurality of first switches S1 to open or close. It should be noted that, in FIG. 6 , since only one first electrode 222 is shown, correspondingly, only one first switch S1 is shown.

The detection unit 24 controls the plurality of first switches S1 to be sequentially turned off through the control circuit 242 to control the plurality of first electrodes 222 to be floating in sequence.

When the capacitive sensing device 200 performs sensing, after the control circuit 242 controls the first switch S1 to be turned off for a predetermined time, the first switch S1 that is currently turned off is closed, and the other one is turned off. The first switch S1. Therefore, the plurality of first switches S1 are sequentially turned off, so that the plurality of first electrodes 222 are suspended in the air in sequence, thereby realizing a sensing operation.

In some implementations, the predetermined reference voltage signal Vp is a constant voltage signal modulated by the modulating signal M. However, alternatively, the predetermined reference voltage signal Vp can also be a constant voltage signal. Wherein, when the predetermined reference voltage signal Vp is a constant voltage signal, the reference circuit 240 is preferably provided in the control chip instead of the sensing chip. The reference circuit 240 in the control chip uses system ground or device ground as a voltage reference. The signal on the system ground or equipment ground is generally a constant voltage signal of 0 volts.

In some implementations, the first switch S1 may be a thin film transistor switch. For example, amorphous silicon thin film transistor switches, low temperature polysilicon thin film transistor switches, high temperature polysilicon thin film transistor switches, metal oxide thin film transistor switches and so on. Wherein the metal oxide thin film transistor switch is, for example, an indium gallium zinc oxide (IGZO) thin film transistor switch. Correspondingly, the gate is a control electrode for controlling on/off of the switch; the source is the first transfer electrode and is connected to the reference circuit 240 ; the drain is the second transfer electrode and is connected to the first electrode 222 . However, alternatively, in other implementation manners, the first switch S1 may also be another suitable type of switch, such as a bipolar transistor switch. Certainly, the first switch S1 may also be an electromagnetic switch, such as a relay. For example, when the first switches S1 are suitable types of switches such as thin film transistors, the plurality of first switches S1 can be directly formed on the substrate 220 , thereby reducing manufacturing costs.

Please refer to FIG. 6 again. In some embodiments, the detection unit 24 may further include a plurality of signal reading circuits 244, and the plurality of signal reading circuits 244 are used to connect to the plurality of second electrodes 222, An excitation signal Vref is provided to the plurality of second electrodes 224, and a sensing signal Vd outputted by the plurality of second electrodes 224 is received to obtain sensing information. In this embodiment, the number of the plurality of signal reading circuits 244 is equal to the number of the second electrodes 224 , and the plurality of signal reading circuits 244 are connected to the plurality of second electrodes 224 in a one-to-one correspondence. The plurality of signal reading circuits 244 can output the excitation signal Vref to all the second electrodes 222 at the same time, and simultaneously read the sensing signals Vd output by all the second electrodes 224 at one time.

It should be noted that, in FIG. 6 , only one second electrode 224 is shown, therefore, for clarity, only one signal reading circuit 244 is shown in the detection unit 24 . However, in fact, each second electrode 224 is correspondingly connected to a signal reading circuit 244 .

Alternatively, in some other implementation manners, the number of the plurality of signal reading circuits 244 is less than the number of the plurality of second electrodes 224 . Correspondingly, at least part or all of the signal reading circuits 244 are multiplexed, and the second electrodes 224 located at different positions are time-divisionally driven to work.

In some modified implementation manners, as shown in FIG. 7 , the detection unit 24 may further include a plurality of second switches S2. The plurality of second switches S2 are connected to the plurality of second electrodes 224 in a one-to-one correspondence. The control circuit 242 is connected to the plurality of second switches S2 for controlling the plurality of second switches S2 to be opened or closed. The number of the plurality of signal reading circuits 244 is less than the number of the plurality of second switches S2. At least part or all of the signal reading circuits 244 are respectively connected to at least two second switches S2, and the signal reading circuits 244 connected to the at least two second switches S2 time-divisionally drive the second electrodes 224 respectively connected to the at least two second switches S2 .

In the embodiment shown in FIG. 7 , the number of the plurality of second switches S2 is twice that of the plurality of signal reading circuits 244 , and each signal reading circuit 244 is respectively connected to two second switches S2 . Correspondingly, the control circuit 242, for example, simultaneously controls half of the second switches S2 to be closed each time, and all the signal reading circuits 244 simultaneously drive half of the second electrodes 224 to work through half of the closed second switches S2 each time. , by switching twice, the multiple signal reading circuits 244 drive all the second electrodes 224 to perform a complete detection. In this way, through time-division multiplexing, the number of the plurality of signal reading circuits 244 is greatly reduced, thereby reducing the manufacturing cost of the capacitive sensing device 200 .

During operation, when the detection unit 24 is sequentially disconnected from the plurality of first electrodes 222 , the plurality of signal reading circuits 244 are electrically connected to the plurality of second electrodes 224 in time division. The opening or closing of the second switch S2 is controlled by the control circuit 242 , so that the plurality of signal reading circuits 244 read the sensing signal Vd output by the second electrode 224 in time division. As shown in FIG. 7, each signal reading circuit 244 is connected to two second switches S2. Taking the first signal reading circuit 244 on the left as an example, when reading the sensing signal Vd, The control circuit 242 first controls a second switch S2a connected to the signal reading circuit 244 and located on the left to close, and controls the second switch S2b located on the right to open; to be connected with the second switch S2a After the sensing signal Vd of the connected second electrode 224 is read, the control circuit 242 controls another second switch S2b connected to the signal reading circuit 244 to close, and the second switch S2a to open, so as to read the The second switch S2b is connected to the sensing signal Vd of the second electrode 224 .

It should be noted that, for clear distinction, the two second switches S2 connected to the first signal reading circuit 244 on the left are respectively marked as S2a and S2b here.

For another example, the number of the plurality of second switches S2 is three times that of the plurality of signal reading circuits 244, each signal reading circuit 244 is connected to three second switches S2, correspondingly, all signal reading circuits The circuit 244 simultaneously drives one-third of the second electrodes 224 to work at the same time, and through three switching times, the plurality of signal reading circuits 244 drives all the second electrodes 224 to perform a complete detection. The number of signal reading circuits 244 mentioned above in this application is just an example. However, this application is not limited thereto. Manufacturers can set a corresponding number of signal reading circuits 244 according to product specifications and product quality requirements.

When the plurality of second switches S2 are suitable types of switches such as thin film transistors, the plurality of second switches S2 can also be disposed on the substrate 220 .

Please refer to FIG. 6 and FIG. 7 together, the control circuit 242 controls the first switch S1 to be turned off row by row, for example. However, alternatively, the control circuit 242 may also control the first switches S1 to be turned off alternately. For example, the control circuit 242 first controls the first switches S1 in the odd rows to be turned off one by one, and then controls the first switches S1 in the even rows to turn off one by one. A switch S1 is turned off one by one. The control circuit 242 controls the disconnection sequence of the plurality of first switches S1 from the method listed here, as long as the control circuit 242 controls the current disconnection of the first switch S1, and controls the previous disconnection. The first switch S1 of the first switch S1 is closed. According to such a control method, the method of controlling all the first switches S1 to be turned off in turn should fall within the scope of protection of the present application.

The reference circuit 240 in FIG. 7 has an output terminal (not marked) to output a predetermined reference voltage signal, and the output terminals are respectively connected to a plurality of first switches S1 , thereby reducing the manufacturing cost of the capacitive sensing device 200 . However, alternatively, a plurality of reference circuits may also be provided, each reference circuit correspondingly outputs a predetermined reference voltage signal, and each reference signal source is connected to a plurality of first switches S1 in a one-to-one correspondence. Alternatively, the reference circuit 240 includes multiple output terminals, and the multiple output terminals are connected to the multiple first switches S1.

Please refer to FIG. 7 and FIG. 8 together. In some implementations, the signal reading circuit 244 includes an amplifier Q and a feedback branch F. As shown in FIG. Wherein, the amplifier Q includes a non-inverting terminal a, an inverting terminal b, a grounding terminal c, a power supply terminal d, and an output terminal Vout, and the feedback branch F is connected between the inverting terminal b and the output terminal Vout In between, the inverting terminal b is further connected to the second electrode 224 through the second switch S2. The non-inverting terminal a is used to receive the excitation signal Vref. The ground terminal c is used to load the modulation signal M. The power supply terminal d is used for loading a power supply voltage. The feedback branch F includes a feedback capacitor CB and a third switch S3, and the feedback capacitor CB and the third switch S3 are connected in parallel between the inverting terminal b and the output terminal Vout.

When working, the amplifier Q is in a virtual short state, and the voltages at the non-inverting terminal a and the inverting terminal a are the same. Correspondingly, the excitation signal Vref is output to the second electrode 224 through the non-inverting terminal a, the inverting terminal b, and the closed second switch S2 in sequence. At the same time, the control circuit 242 (see FIG. 6 ) controls the plurality of first switches S1 to be turned off sequentially, and the reference circuit 240 provides a predetermined reference voltage signal Vp to the first electrode 222 through the closed first switches S1 . For example, when a finger 400 (see FIG. 6 ) approaches the suspended first electrode 222, since the first coupling capacitance CS formed between the finger 400 and the suspended first electrode 222 is connected in series with the second coupling capacitance CF in the signal reading The first electrode 222 is between the circuit 244 and the ground, and the first electrode 222 is used as a shielding electrode. Therefore, the corresponding output sensing signals Vd of the plurality of second electrodes will be different. Wherein, the second electrode 224 is used to output the corresponding sensing signal Vd to the output terminal Vout through the feedback branch F. Therefore, the detection unit 24 can obtain corresponding sensing information according to the sensing signals Vd output by the plurality of second electrodes 224 . For example, fingerprint image information is acquired, or touch operation information is acquired.

It should be noted that, when the capacitive sensing device 200 performs fingerprint sensing, for example, since the fingerprint of the finger 400 includes ridges and valleys, a first coupling capacitance CS is formed between the ridges and the suspended first electrode 222. The capacitance value is greater than the capacitance value of the first coupling capacitor CS formed between the valley and the suspended first electrode 222 .

The signal reading circuit 244 is not limited to the circuit shown in FIG. 8 of the present application, and may also be other suitable types of circuits, as long as it can transmit the excitation signal Vref to the second electrode 224 and receive the output from the second electrode 224. The sensing signal Vd falls within the protection scope of the present application.

In addition, in the detection unit 24 of the present application, a filter circuit, an amplification circuit, an analog-to-digital conversion circuit and other circuits may be selected to be further added after the output terminal Vout.

Please refer to FIG. 9 . FIG. 9 is a schematic structural diagram of an embodiment of the electronic device of the present application. The electronic device 500 is for example but not limited to any suitable type of product such as consumer electronics, household electronics, vehicle electronics, or wearable electronics. Among them, the consumer electronic products are, for example, various suitable electronic products such as mobile phones, tablet computers, notebook computers, desktop monitors, and all-in-one computers. Household electronic products are, for example, smart door locks, televisions, refrigerators and other suitable electronic products. Vehicle-mounted electronic products are, for example, various suitable electronic products such as vehicle-mounted navigators and vehicle-mounted DVDs. Wearable electronic products are, for example, various suitable electronic products such as watches, bracelets, and rings.

The electronic device 500 includes the capacitive sensing device 200 in any one of the above-mentioned implementation manners.

In some implementations, the electronic device 500 may further include a display area 501 and a non-display area 502 . Wherein, the electronic device 500 is provided with a display screen corresponding to the display area 501 for displaying images and the like. The non-display area 502 is located around the display area 501 . Generally, the front of the electronic device 500 includes a protective cover 503 .

The capacitive sensing device 200 is, for example, a biological information sensing module, which is set in the non-display area 502 of the electronic device 500 , for example, in a position corresponding to the Home button. Specifically, the capacitive sensing device 200 can be hidden under the protective cover 503 . Alternatively, the capacitive sensing device 200 may also be exposed at a through hole of the protective cover 503. In addition, the capacitive sensing device 200 may also be disposed at a suitable position such as the side or the back of the electronic device 500 .

Further, when the capacitive sensing device 200 is a biological information sensing module, the capacitive sensing device 200 can also be located in the display area 501, for example, the sensor unit 22 of the capacitive sensing device 200 (See FIG. 3 ) Located in a partial area of the display area 501 .

It should be noted that when the capacitive sensing device 200 is a biological information sensing module, the biological information sensing module can also perform touch sensing.

The sensor unit 22 (see FIG. 3 ) of the capacitive sensing device 200 may also be located in the entire area of the display area 501 . Optionally, the capacitive sensing device 200 performs touch sensing and biometric information sensing. For example, the capacitive sensing device 200 is used to perform touch sensing, and the local area is used to perform biometric information sensing. For another example, the capacitive sensing device 200 may also perform touch sensing and biometric information sensing in a time-sharing manner, so that the electronic device 500 may perform biometric information sensing on a full screen.

In the description of this specification, descriptions referring to the terms "one embodiment", "certain embodiments", "exemplary embodiments", "example", "specific examples", or "some examples" are meant to be combined with The specific features, structures, materials or features described in the above embodiments or examples are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limitations of the present invention, and those skilled in the art are within the scope of the present invention. Variations, modifications, substitutions and variations can be made to the above-described embodiments.

Claims (31)

1. a kind of capacitance-type sensing device, comprising:

Sensor unit, including a plurality of first electrode and a plurality of second electrode, a plurality of first electrode and described a plurality of second Electrode insulation cross arrangement；

Modulation unit, for generating modulated signal；With

Detection unit, for receiving the modulated signal, and by providing pumping signal to a plurality of second electrode, control institute It is successively hanging and provide a scheduled reference voltage signal to not hanging first electrode, to drive to state a plurality of first electrode The sensor unit executes sensing operation；

Wherein, the pumping signal is to pass through the modulated signal of the modulated signal.

2. capacitance-type sensing device as described in claim 1, it is characterised in that: the detection unit is further received from the The sensing signal of two electrodes output, to obtain sensitive information.

3. capacitance-type sensing device as described in claim 1, it is characterised in that: the scheduled reference voltage signal is one permanent Determining voltage signal, or, the scheduled reference voltage signal is that a constant voltage signal is modulated by the modulated signal Signal.

4. capacitance-type sensing device as described in claim 1, it is characterised in that: the sensor unit further comprises insulation Substrate and insulating layer, a plurality of second electrode are arranged on the insulating substrate, and the insulating layer setting is described a plurality of the On two electrodes, a plurality of first electrode is arranged on the insulating layer.

5. capacitance-type sensing device as claimed in claim 4, it is characterised in that: the sensor unit further includes protective layer, The protective layer setting is in the second electrode.

6. capacitance-type sensing device as claimed in claim 4, it is characterised in that: a plurality of first electrode is arranged in parallel, institute It is arranged in parallel to state a plurality of second electrode, and square crossing is arranged between a plurality of first electrode and a plurality of second electrode.

7. capacitance-type sensing device as claimed in claim 5, it is characterised in that: the modulation unit is integrated in a control chip In, the detection unit is integrated in a sensor chip, and the control chip and the sensor chip are arranged in the insulation base On plate.

8. capacitance-type sensing device as claimed in claim 4, it is characterised in that: the modulation unit is integrated in a control chip In, the detection unit is integrated in a sensor chip, and the control chip and the sensor chip are arranged in the insulation base On plate；The capacitance-type sensing device further includes a packaging body, for coating the sensor unit, the sensor chip, institute State the gap between control chip, and the filling sensor unit, the sensor chip, the control chip.

9. capacitance-type sensing device as described in claim 1, it is characterised in that: a plurality of first electrode is used for capacitor square Formula is coupled to target object, and the capacitance-type sensing device is used to sense the touch for whether having the target object, and/or, sense Survey the biological information of the target object.

10. capacitance-type sensing device as claimed in claim 9, it is characterised in that: hanging first electrode is used for and the mesh The first coupled capacitor is formed between mark object, infall forms the between a plurality of first electrode and a plurality of second electrode Two coupled capacitors, first coupled capacitor and second coupled capacitor are connected in series in the detection unit and the earth Between.

11. capacitance-type sensing device as described in claim 1, it is characterised in that: be applied with the scheduled reference voltage letter Number first electrode be used as bucking electrode.

12. capacitance-type sensing device as described in claim 1, it is characterised in that: the detection unit is by disconnecting and first The connection of electrode, comes so that the first electrode is hanging, when the detection unit is when disconnecting the connection with a first electrode, It re-starts with the first electrode disconnected before and is electrically connected.

13. capacitance-type sensing device as described in claim 1, it is characterised in that: the signal in the detection unit be through The modulated signal of modulated signal.

14. capacitance-type sensing device as described in claim 1, it is characterised in that: the detection unit further comprises ground connection End, the modulation unit is for exporting the modulated signal to the ground terminal, the earth signal as the detection unit.

15. the capacitance-type sensing device as described in any one of claim 1-14, it is characterised in that: the detection unit packet Include reference circuit, multiple first switches and control circuit, the reference circuit by the multiple first switch with it is described a plurality of The corresponding connection of first electrode, the reference circuit are used to provide the described scheduled reference voltage, the control circuit and described more A first switch connection, is opened or closed for controlling the multiple first switch.

16. capacitance-type sensing device as claimed in claim 15, it is characterised in that: the detection unit passes through the control electricity Road controls the multiple first switch and successively disconnects, to realize that the control a plurality of first electrode is successively hanging.

17. capacitance-type sensing device as claimed in claim 16, it is characterised in that: when control circuit control one described the One switch was disconnected up to after the scheduled time, was closed the first switch currently disconnected, and was disconnected the first of another closure again and opened It closes.

18. capacitance-type sensing device as claimed in claim 16, it is characterised in that: the control circuit is the multiple in control When a first switch in first switch disconnects, remaining first switch closure is controlled.

19. capacitance-type sensing device as claimed in claim 15, it is characterised in that: the detection unit further comprises signal Reading circuit, the signal read circuits are used to connect with a plurality of second electrode, provide pumping signal to second electrode, and The sensing signal of the second electrode output is received, to obtain sensitive information.

20. capacitance-type sensing device as claimed in claim 19, it is characterised in that: the detection unit further comprises multiple Second switch and multiple signal read circuits, the multiple second switch and a plurality of second electrode correspond and connect It connects, the control circuit is connect with the multiple second switch, is opened or closed for controlling the multiple second switch, described The number of signal read circuits is less than the number of the second switch.

21. capacitance-type sensing device as claimed in claim 20, it is characterised in that: signal-obtaining electricity at least partially or fully Road is separately connected at least two second switches, when the detection unit is successively disconnected with the connection of a plurality of first electrode, institute The signal read circuits stated at least partially or fully are electrically connected for timesharing with a plurality of second electrode.

22. capacitance-type sensing device as claimed in claim 21, it is characterised in that: the signal read circuits include amplifier And feedback branch, wherein the amplifier includes in-phase end, reverse side and output end, and the feedback branch is connected to described anti- Between output end described in Xiang Duanhe, the reverse side further connects second electrode by second switch, and the in-phase end is used for Receive the pumping signal.

23. capacitance-type sensing device as claimed in claim 22, it is characterised in that: the amplifier further comprises ground connection End, the ground terminal is for receiving the modulated signal.

24. capacitance-type sensing device as described in claim 1, it is characterised in that: the capacitance-type sensing device is to touch to pass One or more of induction device, biological information sensing device.

25. capacitance-type sensing device as claimed in claim 24, it is characterised in that: the capacitance-type sensing device is fingerprint biography Induction device.

26. a kind of electronic equipment, including such as the described in any item capacitance-type sensing devices of claim 1-25.

27. electronic equipment as claimed in claim 26, it is characterised in that: the electronic equipment includes mobile terminal, intelligent family Occupy product, vehicle electronics product, any one or a few in wearable electronic product.

28. electronic equipment as claimed in claim 26, it is characterised in that: the electronic equipment includes viewing area and non-display Area, the capacitance-type sensing device are located at viewing area or are located at non-display area.

29. electronic equipment as claimed in claim 28, it is characterised in that: when the capacitance-type sensing device is located at non-display area When, the capacitance-type sensing device is biological information sensing mould group.

30. electronic equipment as claimed in claim 28, it is characterised in that: when the capacitance-type sensing device is located at viewing area When, the regional area or whole region of the viewing area of the electronic equipment can be used for executing biological information sensing.

31. electronic equipment as claimed in claim 28, it is characterised in that: the capacitance-type sensing device touches sense for executing It surveys, part of region is further used for executing biological information sensing.