Fingerprint acquisition device

Abstract

The utility model provides a fingerprint acquisition device, relates to the technical field of fingerprint identification, and aims to solve the problem of mistaken touch in fingerprint identification. The fingerprint acquisition device comprises a switch and a fingerprint module, the switch comprises a first switch and / or a second switch, the first switch is electrically connected between a pressure-sensitive device and the fingerprint module, and the second switch is electrically connected between the pressure-sensitive device and a processor of the electronic equipment. The capacitance of the pressure-sensitive device changes along with the magnitude of the pressure borne by the pressure-sensitive device; the fingerprint module is electrically connected with a processor of the electronic equipment, and the fingerprint module comprises a pressure detection module and a fingerprint acquisition module; the pressure detection module generates an electric signal corresponding to pressure when a finger touches the fingerprint module, and the fingerprint acquisition module is used for acquiring a fingerprint image.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202411017749.7, filed on July 26, 2024, entitled "A fingerprint recognition device and a fingerprint recognition method", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of fingerprint recognition technology, and in particular to a fingerprint acquisition device. Background Technology

[0004] With the widespread adoption of mobile internet and the indispensable role of mobile phones in daily life, the security of mobile phones has become increasingly important. Fingerprint recognition technology has emerged as a result and has quickly become a crucial component of security verification methods for unlocking phones and making payments. Side-mounted fingerprint recognition technology places the fingerprint sensor on the side of the phone, allowing users to quickly unlock the phone or perform payments while holding it.

[0005] As fingerprint recognition becomes more widespread, the demands for its precision are increasing. Compared to optical fingerprint recognition, side-mounted fingerprint recognition, located on the side of the phone, is more prone to accidental touches during handholding, leading to false triggers and impacting user experience. To address this issue, some technologies mitigate the problem by capturing images to determine if they are genuine fingerprints; however, they still cannot solve the problem of unintentional hand or finger touches.

[0006] Therefore, how to identify false touches in fingerprint recognition and achieve accurate fingerprint recognition is a technical problem that urgently needs to be solved. Utility Model Content

[0007] In view of the above problems, embodiments of this application provide a fingerprint acquisition device to overcome or at least partially solve the above problems.

[0008] This application discloses a fingerprint acquisition device, including:

[0009] A switch, including a first switch and / or a second switch, wherein the first switch is electrically connected between the pressure-sensitive device and the fingerprint module, and the second switch is electrically connected between the pressure-sensitive device and the processor of the electronic device, wherein the capacitance of the pressure-sensitive device changes with the magnitude of the pressure applied to it;

[0010] A fingerprint module is electrically connected to the processor of the electronic device. The fingerprint module includes a pressure detection module and a fingerprint acquisition module. The pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module, and the fingerprint acquisition module is used to acquire fingerprint images.

[0011] Optionally, the pressure-sensitive device includes a detection capacitor composed of a first side electrode plate and a second side electrode plate.

[0012] Optionally, the first switch and / or the second switch switch states in response to a control signal generated by the processor;

[0013] In the case where the switch includes the first switch and the second switch, one of the first switch and the second switch is in a closed state and the other is in an open state.

[0014] Optionally, when a finger touches the surface of the fingerprint module, the first switch is in a closed state;

[0015] In the default state and in the event of fingerprint recognition failure, the second switch is in the closed state.

[0016] Optionally, the first end of the first switch is connected to the first electrode plate of the detection capacitor, and the second end of the first switch is connected to the input end of the pressure detection module.

[0017] The first end of the second switch is connected to the first electrode plate of the detection capacitor, and the second end of the second switch is connected to the input terminal of the processor.

[0018] The second electrode plate of the detection capacitor is grounded.

[0019] Optionally, the pressure detection module includes: a third switch, a fourth switch, a fifth switch, an integrator, and a signal processing module;

[0020] The second end of the first switch is connected to the input end of the pressure detection module, including: the second end of the first switch is connected to the first end of the third switch and the first end of the fourth switch respectively;

[0021] The second terminal of the third switch is connected to a reference voltage;

[0022] The fifth switch is connected in parallel with the integrating capacitor of the integrator;

[0023] The input terminal of the integrator is connected to the second terminal of the fourth switch, and the output terminal of the integrator is connected to the input terminal of the signal processing module.

[0024] Optionally, if the switch includes a first switch, the switch further includes a sixth switch, and the fingerprint module further includes a driving voltage module, wherein the sixth switch is electrically connected between the driving voltage module and the pressure-sensitive device;

[0025] In the case where the switch includes a second switch, the switch also includes a seventh switch, which is electrically connected between the pressure-sensitive device and the ground terminal.

[0026] Optionally, the first switch, the second switch, the sixth switch, and the seventh switch switch their states in response to a control signal generated by the processor;

[0027] Specifically, when a finger touches the surface of the fingerprint module, the first switch and the sixth switch are in a closed state; in the default state and in the case of fingerprint recognition failure, the second switch and the seventh switch are in a closed state.

[0028] Optionally, the pressure-sensitive device includes: a detection capacitor composed of a first side electrode plate and a second side electrode plate;

[0029] The first end of the sixth switch is connected to the output end of the driving voltage module, and the second end of the sixth switch is connected to the second electrode plate of the detection capacitor.

[0030] The first terminal of the seventh switch is grounded, and the second terminal of the seventh switch is connected to the second electrode plate of the detection capacitor.

[0031] Optionally, the fingerprint module further includes: a first multiplexer and a signal processing module;

[0032] The output of the pressure detection module is connected to the first input of the first multiplexer, the output of the fingerprint acquisition module is connected to the second input of the first multiplexer, and the output of the first multiplexer is connected to the input of the signal processing module.

[0033] The processor enables the pressure detection module and the fingerprint acquisition module to reuse the signal processing module by controlling the first multiplexer.

[0034] Optionally, the pressure-sensitive device is the power button of the electronic device.

[0035] Optionally, the pressure-sensitive device is disposed between the fingerprint module and the power button of the electronic device, or the power button is disposed between the fingerprint module and the pressure-sensitive device.

[0036] Optionally, the switch includes a first switch and a second switch, wherein the initial state of the first switch is an open state and the initial state of the second switch is a closed state.

[0037] Optionally, it also includes: a first circuit board;

[0038] The pressure-sensitive device and the fingerprint module are connected via a first circuit board;

[0039] The switch is deployed on the first circuit board.

[0040] Optionally, it may also include: a second circuit board and a third circuit board;

[0041] The pressure-sensitive device is deployed on the second circuit board, and the fingerprint module is deployed on the third circuit board;

[0042] The first switch and the second switch are deployed on the second circuit board or the third circuit board, and the sixth switch and the seventh switch are deployed on the second circuit board or the third circuit board.

[0043] The embodiments of this application have the following advantages:

[0044] The fingerprint acquisition device provided in this application includes a switch and a fingerprint module. The switch includes a first switch and / or a second switch. The first switch is electrically connected between a pressure-sensitive device and the fingerprint module, and the second switch is electrically connected between the pressure-sensitive device and the processor of an electronic device. The capacitance of the pressure-sensitive device changes according to the magnitude of the pressure it receives. The fingerprint module is electrically connected to the processor of the electronic device. The fingerprint module includes a pressure detection module and a fingerprint acquisition module. The pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module, and the fingerprint acquisition module is used to acquire a fingerprint image.

[0045] Thus, by controlling the state of the switch, the electrical signal corresponding to the pressure generated when a finger touches the fingerprint module can be obtained, or the function of a pressure-sensitive device can be realized. The electrical signal corresponding to the pressure generated when a finger touches the fingerprint module can reflect whether the finger touches the module accidentally or is actually unlocking the fingerprint recognition device. Therefore, this fingerprint acquisition device can only acquire a fingerprint image when an actual fingerprint recognition action is being performed, avoiding fingerprint recognition unlocking due to accidental touches and improving user experience. Furthermore, by incorporating a pressure detection module and a fingerprint acquisition module into the fingerprint module, and using a single chip to measure the electrical signal corresponding to the pressure generated when a finger touches the fingerprint module and to acquire the fingerprint image, costs are minimized. Attached Figure Description

[0046] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 This is a schematic diagram of an existing capacitive fingerprint recognition structure;

[0048] Figure 2 This is a schematic diagram of the structure of a fingerprint collection device provided in an embodiment of this application;

[0049] Figure 3 This is a schematic diagram of the structure of a pressure-sensitive device provided in an embodiment of this application;

[0050] Figure 4 This is a schematic diagram of the structure of a pressure detection module provided in an embodiment of this application;

[0051] Figure 5 This is a schematic diagram of another fingerprint acquisition device provided in an embodiment of this application;

[0052] Figure 6 This is a schematic diagram of another pressure detection module provided in an embodiment of this application;

[0053] Figure 7 This is a schematic diagram of the structure of a fingerprint acquisition device with a multiplexed signal processing module provided in an embodiment of this application;

[0054] Figure 8 This is a schematic diagram of the structure of a fingerprint acquisition device with another multiplexed signal processing module provided in an embodiment of this application;

[0055] Figure 9 This is a schematic diagram of the module structure of a fingerprint acquisition device provided in an embodiment of this application;

[0056] Figure 10 This is a schematic diagram of the module structure of another fingerprint acquisition device provided in an embodiment of this application;

[0057] Figure 11 This is a flowchart of the steps of a signal processing method provided in an embodiment of this application;

[0058] Figure 12 This is a control timing diagram of a fingerprint acquisition device provided in an embodiment of this application;

[0059] Figure 13 This is a control timing diagram of another fingerprint acquisition device provided in an embodiment of this application;

[0060] Figure 14 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0061] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0062] In related technologies, fingerprint recognition is achieved through the principle of capacitive fingerprint recognition, such as... Figure 1 As shown, Figure 1 This is a schematic diagram of an existing capacitive fingerprint recognition system. Specifically, a metal plate M1 and the fingerprint form a capacitor. A signal excitation U1 is applied to the capacitor to detect the fingerprint ridges.

[0063] However, as fingerprint recognition becomes more widespread, the demands for its precision are increasing. Compared to optical fingerprint recognition, capacitive fingerprint recognition, being located on the side of the phone, is more prone to accidental touches when holding the phone, leading to false triggers and impacting the user experience. To address this issue, related technologies have mitigated some problems by analyzing captured images to determine if they are indeed fingerprints. However, they still struggle to handle unintentional hand or finger touches.

[0064] Therefore, this application provides a fingerprint acquisition device. This device can acquire the electrical signal corresponding to pressure generated when a finger touches the fingerprint module, or function as a pressure-sensitive device. The electrical signal corresponding to pressure generated when a finger touches the fingerprint module can reflect whether it is a mistaken touch or a genuine fingerprint recognition unlocking action. Therefore, this fingerprint acquisition device can only acquire a fingerprint image when a genuine fingerprint recognition unlocking action is being performed. Specifically, when a finger touches the fingerprint module, the device first detects the electrical signal corresponding to pressure generated when the finger touches the fingerprint module. If the electrical signal corresponding to pressure generated when the finger touches the fingerprint module determines that it is a genuine fingerprint recognition unlocking action, then a fingerprint image is acquired through the fingerprint acquisition module. This avoids fingerprint recognition unlocking due to mistaken touch, thereby improving the user experience.

[0065] It is understood that the technical solutions of this application embodiment are not limited to side fingerprint recognition. The fingerprint module in the fingerprint collection device of this embodiment can be set not only on the side of the electronic device (e.g., mobile phone), but also on the front or back.

[0066] The fingerprint acquisition device provided in the embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0067] Reference Figure 2 As shown, Figure 2 This is a schematic diagram of the structure of a fingerprint acquisition device provided in an embodiment of this application. Figure 2 As shown, the fingerprint acquisition device includes:

[0068] A switch, including a first switch and / or a second switch, wherein the first switch is electrically connected between the pressure-sensitive device and the fingerprint module, and the second switch is electrically connected between the pressure-sensitive device and the processor of the electronic device, wherein the capacitance of the pressure-sensitive device changes with the magnitude of the pressure applied to it;

[0069] A fingerprint module is electrically connected to the processor of the electronic device. The fingerprint module includes a pressure detection module and a fingerprint acquisition module. The pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module, and the fingerprint acquisition module is used to acquire fingerprint images.

[0070] In this embodiment, the electronic device refers to a user terminal device, such as a mobile phone or tablet computer. The switch includes a first switch and / or a second switch. The first switch controls the connection / disconnection of the line between the pressure-sensitive device and the fingerprint module, and the second switch controls the connection / disconnection of the line between the pressure-sensitive device and the electronic device. The processor of the electronic device controls the state of the switch to obtain an electrical signal corresponding to the pressure generated when a finger touches the fingerprint module, or inputs the signal generated by the pressure-sensitive device to the processor to realize the function of the pressure-sensitive device. For example, if the electronic device is a mobile phone, the state of the switch is controlled through the input / output ports (IO pins, e.g., control ports) of the mobile phone's CPU (Central Processing Unit).

[0071] When the switch only includes a first switch, the pressure-sensitive device is directly electrically connected to the processor of the electronic device to transmit the signal generated by the pressure-sensitive device (e.g., a power button) to the processor; alternatively, the pressure-sensitive device (e.g., a membrane switch) may not be directly connected to the processor. When the switch only includes a second switch, the pressure-sensitive device is directly electrically connected to the fingerprint module. By setting only a first or second switch in the fingerprint acquisition device, the cost and size of the fingerprint acquisition device are reduced. Furthermore, the scheme with only a second switch has the least noise impact compared to the scheme with only a first switch. When both switches are present, the two circuits do not interfere with each other, resulting in minimal noise impact.

[0072] The switch can include both a first switch and a second switch. The first switch controls the connection between the pressure-sensitive device and the fingerprint module, while the second switch controls the connection between the pressure-sensitive device and the electronic device, enabling flexible switching between the pressure detection module function and the pressure-sensitive device function (e.g., the power button function) in the fingerprint acquisition device. The first and second switches can also form a second multiplexer, allowing for selection based on the processor's control.

[0073] The fingerprint acquisition module can be either a capacitive or an ultrasonic fingerprint acquisition module. Specifically, the pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module. When the processor determines that a fingerprint image needs to be acquired based on this electrical signal, the fingerprint acquisition module acquires the fingerprint image.

[0074] In this embodiment, by controlling the state of the switch, an electrical signal corresponding to the pressure generated when a finger touches the fingerprint module can be obtained, or the function of a pressure-sensitive device can be implemented. The electrical signal corresponding to the pressure generated when a finger touches the fingerprint module can reflect whether the finger touches the module accidentally or is actually performing fingerprint recognition. Therefore, this fingerprint acquisition device can only acquire a fingerprint image when an actual fingerprint recognition action is being performed, avoiding fingerprint recognition due to accidental touch, thereby improving the user experience. Furthermore, by setting a pressure detection module and a fingerprint acquisition module in the fingerprint module, and using a single chip to measure the electrical signal corresponding to the pressure generated when a finger touches the fingerprint module and to acquire the fingerprint image, costs are minimized.

[0075] In an optional embodiment, the first switch and / or the second switch switch a state in response to a control signal generated by the processor; wherein, when the switch includes the first switch and the second switch, one of the first switch and the second switch is in a closed state and the other is in an open state.

[0076] In this embodiment, the processor of the electronic device controls the state of the first switch and / or the second switch. The first switch and / or the second switch switch the state in response to the control signal generated by the processor, thereby realizing the functions of the pressure detection module and the fingerprint acquisition module in the fingerprint acquisition device. That is, the pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module, and then determines whether a fingerprint image needs to be acquired based on the electrical signal. If a fingerprint image needs to be acquired, it is acquired by the fingerprint acquisition module. In some embodiments, the pressure-sensitive device is a power button. The first switch and / or the second switch switch the state in response to the control signal generated by the processor, thereby realizing the flexible switching between the functions of the pressure detection module and the pressure-sensitive device in the fingerprint acquisition device. Specifically, the pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module, and then determines the operation to be performed based on the electrical signal. If the operation to be performed is to activate the function of the pressure-sensitive device, the line between the pressure-sensitive device and the electronic device is connected, and the signal generated by the pressure-sensitive device is input to the processor to realize the function of the pressure-sensitive device. The first switch and the second switch can constitute a second multiplexer, and the selection of the two-to-one switch is realized according to the control of the processor.

[0077] Specifically, when a finger touches the surface of the fingerprint module, the first switch is in a closed state; in the default state and in the case of fingerprint recognition failure, the second switch is in a closed state.

[0078] If the switch only includes the first switch, when the finger touches the surface of the fingerprint module, the first switch is in the closed state. When the pressure detection module generates an electrical signal corresponding to the pressure when the finger touches the fingerprint module, and when it is determined that a fingerprint image needs to be acquired based on the electrical signal, the fingerprint image is acquired through the fingerprint acquisition module. At this time, the first switch is still in the closed state.

[0079] If the switch only includes a second switch, when a finger touches the surface of the fingerprint module, the second switch is in the open state. The pressure detection module generates an electrical signal corresponding to the pressure when the finger touches the fingerprint module. When it is determined that a fingerprint image needs to be acquired based on the electrical signal, the fingerprint acquisition module acquires the fingerprint image. At this time, the second switch is still in the open state. The second switch will be in the closed state in the default state and in the case of fingerprint recognition failure. That is, in the locked screen state, the second switch is closed, and it detects in real time whether the pressure-sensitive device (e.g., the power button) is activated.

[0080] If the switch includes a first switch and a second switch, in the default state, the second switch is closed and the first switch is open. When a finger touches the surface of the fingerprint module, the first switch is closed and the second switch is open. The pressure detection module generates an electrical signal corresponding to the pressure when the finger touches the fingerprint module. When it is determined from the electrical signal that a fingerprint image needs to be acquired, the fingerprint acquisition module acquires the fingerprint image. At this time, the first switch is still closed and the second switch is still open. When it is determined from the electrical signal that the function of the pressure-sensitive device (power button) needs to be implemented, the first switch is open and the second switch is closed to connect the circuit between the pressure-sensitive device and the electronic device, and input the signal generated by the pressure-sensitive device to the processor to realize the function of the pressure-sensitive device.

[0081] In the default state and in the case of fingerprint recognition failure, the second switch is in the closed state, and the pressure-sensitive device performs its own function. For example, if the pressure-sensitive device is a power button, it performs the function of a power button.

[0082] In one optional embodiment, the switch includes a first switch and a second switch, wherein the first switch is initially in an open state and the second switch is initially in a closed state.

[0083] In this embodiment, the initial state of the first switch being open means that the first switch is a normally open switch, and the initial state of the second switch being closed means that the second switch is a normally closed switch. In the initial state, the pressure-sensitive device performs its function. Figure 2 As shown, the first switch is initially in the open state, and the second switch is initially in the closed state, connecting the pressure-sensitive device to the processor of the electronic device to realize the function of the pressure-sensitive device itself.

[0084] In one alternative embodiment, the pressure-sensitive device is the power button of the electronic device.

[0085] In this way, the fingerprint sensor reuses the power button in the electronic device as a pressure sensor, eliminating the need for additional components in the electronic device and thus reducing costs. Furthermore, the functions of the pressure sensor and the fingerprint sensor are independent; if the fingerprint sensor is damaged, the function of the pressure sensor will not be affected.

[0086] In one optional embodiment, the pressure-sensitive device is disposed between the fingerprint module and the power button of the electronic device, or the power button is disposed between the fingerprint module and the pressure-sensitive device.

[0087] In this embodiment, the pressure-sensitive device is independent of the power button. For example, the pressure-sensitive device can be a separate membrane switch or dome switch. By placing the pressure-sensitive device between the fingerprint module and the power button of the electronic device, or placing the power button between the fingerprint module and the pressure-sensitive device, when a finger touches the fingerprint module, the pressure-sensitive device receives corresponding pressure. The capacitance of the pressure-sensitive device changes according to the magnitude of the pressure, resulting in an electrical signal corresponding to the pressure generated by the pressure detection module.

[0088] For example, Figure 3 This is a schematic diagram of a pressure-sensitive device provided in an embodiment of this application. The pressure-sensitive device includes: a detection capacitor composed of a first side electrode plate and a second side electrode plate, and may also include a cover plate above the first side electrode plate and a base plate below the second side electrode plate; the pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module, including: a change in charge of the detection capacitor when the finger touches the fingerprint module; and generating an electrical signal corresponding to the pressure based on the change in charge.

[0089] In this embodiment, when a finger touches the fingerprint module, the distance between the first and second electrode plates of the pressure-sensitive device changes due to pressure, thereby changing the charge and capacitance of the detection capacitor. The pressure detection module generates an electrical signal corresponding to the pressure based on the charge change. The processor of the electronic device performs corresponding operations based on this pressure-corresponding electrical signal. For example, if it is determined based on the pressure-corresponding electrical signal that the user is performing a genuine fingerprint recognition unlocking action, the processor can control the state of the switch and acquire a fingerprint image through the fingerprint acquisition module in the fingerprint acquisition device.

[0090] Specifically, the first end of the first switch is connected to the first electrode plate of the detection capacitor, and the second end of the first switch is connected to the input terminal of the pressure detection module; the first end of the second switch is connected to the first electrode plate of the detection capacitor, and the second end of the second switch is connected to the input terminal of the processor; the second electrode plate of the detection capacitor is grounded.

[0091] In this way, by controlling the state of the first switch and / or the second switch, the independent switching between the pressure-sensitive device function and the pressure detection module function can be achieved, reducing the impact on the original design of the electronic device and increasing costs less. In addition, the function of the pressure-sensitive device is not affected if the fingerprint acquisition device is damaged.

[0092] In an alternative embodiment, refer to Figure 4 As shown, Figure 4 This is a schematic diagram of the structure of a pressure detection module provided in an embodiment of this application. The pressure detection module includes: a third switch, a fourth switch, a fifth switch, an integrator, and a signal processing module.

[0093] Specifically, the second terminal of the first switch is connected to the first terminal of the third switch and the first terminal of the fourth switch respectively; the second terminal of the third switch is connected to the reference voltage; the fifth switch is connected in parallel with the integrating capacitor of the integrator; the input terminal of the integrator is connected to the second terminal of the fourth switch, and the output terminal of the integrator is connected to the input terminal of the signal processing module.

[0094] In this embodiment, when a finger touches the surface of the fingerprint module, the first switch is closed, and the processor of the electronic device controls the states of the third, fourth, and fifth switches to make the pressure detection module generate an electrical signal corresponding to the pressure when the finger touches the fingerprint module.

[0095] The third switch controls the connection between the reference voltage and the sensing capacitor. When the third switch is closed, the connection between the reference voltage and the sensing capacitor is established, charging the sensing capacitor in the pressure-sensitive device by controlling the reference voltage. The fourth switch controls the connection between the sensing capacitor and the integrator input. When the fourth switch is closed, the charge on the sensing capacitor is transferred to the integrating capacitor in the integrator, causing the integrator to output a voltage signal based on the transferred charge. The fifth switch is connected in parallel with the integrating capacitor of the integrator and is used to reset the integrating capacitor; that is, when the fifth switch is closed, the potential of the integrating capacitor is reset to 0.

[0096] The signal processing module includes an amplifier and an analog-to-digital converter. In specific implementation, by controlling the third, fourth, and fifth switches, the charge on the sensing capacitor in the pressure-sensitive device is transferred to the integrating capacitor in the integrator. The integrator then outputs a voltage signal based on the transferred charge. The signal processing module processes this voltage signal to obtain an electrical signal corresponding to the pressure. Finally, the fingerprint module transmits this pressure-corresponding electrical signal to the processor via an electrical connection (e.g., an ISP bus) so that the processor can subsequently perform corresponding operations based on this signal.

[0097] In an alternative embodiment, refer to Figure 5 As shown, Figure 5 This is a schematic diagram of another fingerprint acquisition device provided in an embodiment of this application. Specifically, the fingerprint acquisition device includes:

[0098] A fingerprint module is electrically connected to the processor of the electronic device. The fingerprint module includes a pressure detection module and a fingerprint acquisition module. The pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module, and the fingerprint acquisition module is used to acquire fingerprint images.

[0099] The switch, in the case that the switch includes a first switch, further includes a sixth switch, and the fingerprint module further includes a driving voltage module, the sixth switch being electrically connected between the driving voltage module and the pressure-sensitive device; in the case that the switch includes a second switch, the switch further includes a seventh switch, the seventh switch being electrically connected between the pressure-sensitive device and the ground terminal.

[0100] In this embodiment, the driving voltage module outputs a driving voltage to the pressure-sensitive device to control the charging of the sensing capacitor. A first switch controls the connection between the pressure-sensitive device and the fingerprint module, a second switch controls the connection between the pressure-sensitive device and the electronic device, a sixth switch controls the connection between the driving voltage module and the pressure-sensitive device, and a seventh switch controls the connection between the pressure-sensitive device and the ground terminal. The sixth and seventh switches can form a third multiplexer, allowing for selection based on the processor's control. The processor of the electronic device controls the switch states to obtain the electrical signal corresponding to the pressure generated when a finger touches the fingerprint module, or inputs the signal generated by the pressure-sensitive device to the processor, thus realizing the function of the pressure-sensitive device.

[0101] When the switch includes only the first and sixth switches, the pressure-sensitive device is directly electrically connected to or not connected to the processor of the electronic device, and the other end of the pressure-sensitive device is directly grounded; when the switch includes only the second and seventh switches, the pressure-sensitive device is directly electrically connected to the fingerprint module. By setting only the first and sixth switches, or only the second and seventh switches, the cost and size of the fingerprint acquisition device are reduced, and the noise impact is minimized.

[0102] The switch can include a first switch, a second switch, a sixth switch, and a seventh switch. The first and sixth switches control the connection between the pressure-sensitive device and the fingerprint module, while the second and seventh switches control the connection between the pressure-sensitive device and the electronic device. This allows for flexible switching between the pressure detection module function and the pressure-sensitive device function (e.g., the power button function) in the fingerprint acquisition device.

[0103] In this embodiment, by controlling the state of the switch, an electrical signal corresponding to the pressure generated when a finger touches the fingerprint module can be obtained, or the function of a pressure-sensitive device can be implemented. The electrical signal corresponding to the pressure generated when a finger touches the fingerprint module can reflect whether the finger touches the module accidentally or is actually performing fingerprint recognition. Therefore, this fingerprint acquisition device can only acquire a fingerprint image when an actual fingerprint recognition action is being performed, avoiding fingerprint recognition due to accidental touch, thereby improving the user experience. Furthermore, by setting a pressure detection module and a fingerprint acquisition module in the fingerprint module, and using a single chip to measure the electrical signal corresponding to the pressure generated when a finger touches the fingerprint module and to acquire the fingerprint image, costs are minimized.

[0104] In one alternative embodiment, the first switch, the second switch, the sixth switch, and the seventh switch switch states in response to a control signal generated by the processor.

[0105] Specifically, when a finger touches the surface of the fingerprint module, the first switch and the sixth switch are in a closed state; in the default state and in the case of fingerprint recognition failure, the second switch and the seventh switch are in a closed state.

[0106] In this embodiment, the processor of the electronic device controls the states of the first switch, the second switch, the sixth switch, and the seventh switch. The first switch, the second switch, the sixth switch, and the seventh switch switch switch states in response to the control signals generated by the processor, thereby realizing the functions of the pressure detection module and the fingerprint acquisition module in the fingerprint acquisition device. Specifically, the pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module, and then determines whether a fingerprint image needs to be acquired based on the electrical signal. If a fingerprint image needs to be acquired, it is acquired by the fingerprint acquisition module. In some embodiments, the pressure-sensitive device is a power button, and the first switch and / or the second switch switch states in response to the control signals generated by the processor, enabling flexible switching between the pressure detection module function and the pressure-sensitive device function in the fingerprint acquisition device. Specifically, the pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module, and then determines the operation to be performed based on the electrical signal. If the operation to be performed is to activate the pressure-sensitive device, the line between the pressure-sensitive device and the electronic device is connected, and the signal generated by the pressure-sensitive device is input to the processor to realize the function of the pressure-sensitive device.

[0107] If the switch only includes the first switch and the sixth switch, when the finger touches the surface of the fingerprint module, the first switch and the sixth switch are in the closed state. When the pressure detection module generates an electrical signal corresponding to the pressure when the finger touches the fingerprint module, and when it is determined that a fingerprint image needs to be acquired based on the electrical signal, the fingerprint image is acquired through the fingerprint acquisition module. At this time, the first switch and the sixth switch are still in the closed state.

[0108] If the switch only includes the second switch and the seventh switch, when the finger touches the surface of the fingerprint module, the second switch and the seventh switch are in the off state. The pressure detection module generates an electrical signal corresponding to the pressure when the finger touches the fingerprint module. When it is determined that a fingerprint image needs to be acquired based on the electrical signal, the fingerprint image is acquired through the fingerprint acquisition module. At this time, the second switch and the seventh switch are still in the off state.

[0109] If the switch includes a first switch, a second switch, a sixth switch, and a seventh switch, in the default state, the second and seventh switches are closed, and the first and sixth switches are open. When a finger touches the surface of the fingerprint module, the first and sixth switches are closed, and the second and seventh switches are open. The pressure detection module generates an electrical signal corresponding to the pressure when the finger touches the fingerprint module. When it is determined from the electrical signal that a fingerprint image needs to be acquired, the fingerprint acquisition module acquires the fingerprint image. At this time, the first and sixth switches are still closed, and the second and seventh switches are still open. When it is determined from the electrical signal that the function of the pressure-sensitive device (power button) needs to be implemented, the first and sixth switches are open, and the second and seventh switches are closed to connect the circuit between the pressure-sensitive device and the electronic device, so that the signal generated by the pressure-sensitive device is input to the processor to realize the function of the pressure-sensitive device.

[0110] In the default state and in the case of fingerprint recognition failure, the second switch and the seventh switch are in the closed state, and the pressure-sensitive device performs its own function. For example, if the pressure-sensitive device is a power button, it performs the function of a power button.

[0111] In one optional embodiment, the pressure-sensitive device includes: a detection capacitor composed of a first side electrode plate and a second side electrode plate; a first terminal of the sixth switch is connected to the output terminal of the driving voltage module, and a second terminal of the sixth switch is connected to the second side electrode plate of the detection capacitor; a first terminal of the seventh switch is grounded, and a second terminal of the seventh switch is connected to the second side electrode plate of the detection capacitor.

[0112] Thus, by controlling the states of the first, second, sixth, and seventh switches, the functions of the pressure-sensitive device and the pressure detection module can be independently switched, reducing the impact on the original design of the electronic device and minimizing cost increases. Furthermore, the function of the pressure-sensitive device remains unaffected even if the fingerprint acquisition device is damaged. Moreover, by driving the voltage output to the pressure-sensitive device through the driving voltage module to control the charging of its detection capacitor, the anti-interference performance of the fingerprint acquisition device is improved.

[0113] Reference Figure 6 As shown, Figure 6This is a schematic diagram of another pressure detection module provided in an embodiment of this application. The pressure detection module includes: a third switch, a fourth switch, a fifth switch, an integrator, and a signal processing module.

[0114] Specifically, the first end of the sixth switch is connected to the output end of the driving voltage module, and the second end of the sixth switch is connected to the second electrode plate of the detection capacitor; the second end of the first switch is connected to the first end of the third switch and the first end of the fourth switch respectively; the second end of the third switch is connected to the reference voltage; the fifth switch is connected in parallel with the integrating capacitor of the integrator; the input end of the integrator is connected to the second end of the fourth switch, and the output end of the integrator is connected to the input end of the signal processing module.

[0115] In this embodiment, when a finger touches the surface of the fingerprint module, the first and sixth switches are closed, while the second and seventh switches are open. The processor of the electronic device controls the states of the third, fourth, and fifth switches to cause the pressure detection module to generate an electrical signal corresponding to the pressure when a finger touches the fingerprint module. Specifically, the third switch controls the connection between the reference voltage and the detection capacitor. When the third switch is closed, it connects the reference voltage to the detection capacitor, charging the detection capacitor in the pressure-sensitive device using the reference voltage. When the third switch is open, it controls the drive voltage module to generate a square wave signal, driving the second electrode plate of the detection capacitor to control the charging of the detection capacitor. The fourth switch controls the connection between the detection capacitor and the integrator input. When the fourth switch is closed, it transfers the charge on the detection capacitor to the integrating capacitor in the integrator, causing the integrator to output a voltage signal based on the transferred charge. The fifth switch is connected in parallel with the integrating capacitor of the integrator and is used to reset the integrating capacitor; that is, when the fifth switch is closed, it resets the potential of the integrating capacitor to 0.

[0116] The signal processing module includes an amplifier and an analog-to-digital converter. In practice, by controlling the third, fourth, and fifth switches, the charge on the sensing capacitor in the pressure-sensitive device is transferred to the integrating capacitor in the integrator. The integrator then outputs a voltage signal based on the transferred charge. The signal processing module processes this voltage signal to obtain an electrical signal corresponding to the pressure. Finally, the fingerprint module transmits this pressure-corresponding electrical signal to the processor of the electronic device via an electrical connection (e.g., an ISP bus), allowing the processor to subsequently perform corresponding operations based on this pressure-corresponding signal.

[0117] In an alternative embodiment, refer to Figure 7 As shown, Figure 7This is a schematic diagram of the structure of a fingerprint acquisition device with a multiplexed signal processing module provided in an embodiment of this application. Figure 7 As shown, the fingerprint acquisition device includes:

[0118] A switch, including a first switch and / or a second switch, wherein the first switch is electrically connected between the pressure-sensitive device and the fingerprint module, and the second switch is electrically connected between the pressure-sensitive device and the processor of the electronic device, wherein the capacitance of the pressure-sensitive device changes with the magnitude of the pressure applied to it.

[0119] A fingerprint module is electrically connected to the processor of the electronic device. The fingerprint module includes a pressure detection module and a fingerprint acquisition module. The pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module, and the fingerprint acquisition module is used to acquire fingerprint images.

[0120] A first multiplexer and a signal processing module; the output of the pressure detection module is connected to the first input of the first multiplexer, the output of the fingerprint acquisition module is connected to the second input of the first multiplexer, and the output of the first multiplexer is connected to the input of the signal processing module; the processor, through control of the first multiplexer, enables the pressure detection module and the fingerprint acquisition module to multiplex the signal processing module.

[0121] In this embodiment, when a finger touches the surface of the fingerprint module, the processor of the electronic device controls the first input terminal and the output terminal of the first multiplexer to connect, so as to obtain an electrical signal corresponding to the pressure through the pressure detection module and the signal processing module. When it is necessary to acquire a fingerprint image, the processing unit of the electronic device controls the second input terminal and the output terminal of the first multiplexer to connect, so as to obtain the acquired fingerprint image through the fingerprint acquisition module and the signal processing module.

[0122] In the case of a multiplexed signal processing module, the pressure detection module does not include a signal processing module consisting of an amplifier and a digital-to-analog converter. Instead, the pressure detection module includes a third switch, a fourth switch, a fifth switch, and an integrator. The second terminal of the first switch is connected to the first terminals of the third and fourth switches; the second terminal of the third switch is connected to a reference voltage; the fifth switch is connected in parallel with the integrating capacitor of the integrator; the input terminal of the integrator is connected to the second terminal of the fourth switch, and the output terminal of the integrator is connected to the first input terminal of a first multiplexer. Specifically, when a finger touches the surface of the fingerprint module, the first switch is closed and the second switch is open. The states of the third, fourth, and fifth switches in the pressure detection module are controlled, transferring the charge on the sensing capacitor in the pressure-sensitive device to the integrating capacitor in the integrator. This causes the integrator to output a voltage signal based on the transferred charge. The voltage signal output by the integrator is then input to the signal processing module via the first multiplexer for signal processing to obtain an electrical signal corresponding to the pressure.

[0123] When the signal processing module is reused, the fingerprint acquisition module includes a fingerprint pixel array and a fingerprint acquisition analog front end. When a fingerprint image needs to be acquired, the fingerprint ridge signal of the finger is acquired through the fingerprint pixel array and the fingerprint acquisition analog front end in the fingerprint acquisition module, and the acquired fingerprint ridge signal is input to the signal processing module for processing through a first multiplexer to obtain a fingerprint image.

[0124] In this way, by controlling the first multiplexer, the signal processing module can be reused by the pressure detection module and the fingerprint acquisition module, thus eliminating the need to configure separate signal processing modules for the pressure detection module and the fingerprint acquisition module, and reducing the cost of the fingerprint acquisition device.

[0125] Reference Figure 8 As shown, Figure 8 This is a schematic diagram of the structure of a fingerprint acquisition device with another multiplexed signal processing module provided in an embodiment of this application. Figure 8 As shown, the fingerprint acquisition device includes:

[0126] The switch includes a first switch, a second switch, a sixth switch, and a seventh switch. The first switch is electrically connected between the pressure-sensitive device and the fingerprint module. The second switch is electrically connected between the pressure-sensitive device and the processor of the electronic device. The sixth switch is electrically connected between the driving voltage module and the pressure-sensitive device. The seventh switch is electrically connected between the pressure-sensitive device and the ground terminal.

[0127] The fingerprint module is electrically connected to the processor of the electronic device. The fingerprint module includes a pressure detection module, a fingerprint acquisition module, and a driving voltage module. The pressure detection module generates an electrical signal corresponding to the pressure when a finger touches the fingerprint module. The fingerprint acquisition module is used to acquire fingerprint images.

[0128] A first multiplexer and a signal processing module; the output of the pressure detection module is connected to the first input of the first multiplexer, the output of the fingerprint acquisition module is connected to the second input of the first multiplexer, and the output of the first multiplexer is connected to the input of the signal processing module; the processor, through control of the first multiplexer, enables the pressure detection module and the fingerprint acquisition module to multiplex the signal processing module.

[0129] In this embodiment, when a finger touches the surface of the fingerprint module, the processing unit of the electronic device controls the first and sixth switches to close, and the second and seventh switches to open. The first input and output terminals of the first multiplexer are connected, so that an electrical signal corresponding to the pressure is obtained through the pressure detection module and the signal processing module. When a fingerprint image needs to be acquired, the processing unit of the electronic device controls the second input and output terminals of the first multiplexer to be connected, so that the acquired fingerprint image is obtained through the fingerprint acquisition module and the signal processing module.

[0130] In this way, by controlling the first multiplexer, the signal processing module can be reused by the pressure detection module and the fingerprint acquisition module, thus eliminating the need to configure separate signal processing modules for the pressure detection module and the fingerprint acquisition module, and reducing the cost of the fingerprint acquisition device.

[0131] In one optional embodiment, the fingerprint acquisition device further includes: a first circuit board; the pressure-sensitive device and the fingerprint module are connected via the first circuit board; and the switch is deployed on the first circuit board. The fingerprint module and the pressure-sensitive device are deployed on the same module and connected via a circuit board (the first circuit board).

[0132] For example, Figure 9This is a schematic diagram of the module structure of a fingerprint acquisition device provided in this application embodiment. The first circuit board includes a first FPC and a first PCB board above it. The first FPC is fixed in shape by a steel plate structure. The first PCB board is an LGA PCB substrate (Land Grid Array package, Printed Circuit Board). The chip (i.e., the die, which integrates a pressure detection module and a fingerprint acquisition module) is fixed on the first PCB board by die bonding (where die bonding is a chip fixing method). DAF adhesive (DAF is a film material used for electronic packaging) is used between the die and the first PCB board. The chip is connected to the circuit board pads (PCB pads) through the surface pads by gold wire bonding process. EMC (Electromagnetic Compatibility) is encapsulated onto the chip surface by molding process (the encapsulated chip is the fingerprint module). Finally, a coating is covered on the EMC. The color of the coating is generally consistent with the appearance of the electronic device.

[0133] In an optional embodiment, the fingerprint acquisition device further includes: a second circuit board and a third circuit board; the pressure-sensitive device is deployed on the second circuit board, and the fingerprint module is deployed on the third circuit board; the first switch and the second switch are deployed on the second circuit board or the third circuit board, and the sixth switch and the seventh switch are deployed on the second circuit board or the third circuit board.

[0134] For example, Figure 10 This is a schematic diagram of another fingerprint acquisition device module structure provided in this application embodiment. The second circuit board and the third circuit board are connected to the processor of the same electronic device through connectors. Similarly, the second circuit board includes a second FPC and a second PCB board above it. The second PCB board is an LGA PCB substrate. The chip (i.e., the die, which integrates the pressure detection module and the fingerprint acquisition module) is fixed on the second PCB board by die bonding. DAF glue is used between the die and the second PCB board. The chip is connected to the PCB pad through the surface pad by gold wire bonding process. The EMC is packaged onto the chip surface by molding process (the packaged chip is the fingerprint module). Finally, a coating layer is covered on the EMC. The color of the coating layer is generally consistent with the appearance of the electronic device.

[0135] In this application embodiment, two deployment methods for fingerprint acquisition devices are provided. Based on the current pressure-sensitive devices and fingerprint acquisition modules, only a few switches need to be added to the flexible printed circuit board (FPC). This deployment method is easy to implement and increases costs slightly.

[0136] This application also provides a signal processing method, referring to... Figure 11 As shown, Figure 11 This is a flowchart illustrating the steps of a signal processing method provided in an embodiment of this application. The method is applied to the fingerprint acquisition device in this embodiment and includes steps S1110 to S1120:

[0137] Step S1110: When a finger is detected to be in contact with the corresponding fingerprint acquisition area of ​​the fingerprint module, the electrical signal corresponding to the pressure generated by the finger contacting the fingerprint module is detected.

[0138] Step S1120: Perform the corresponding operation based on the comparison result between the electrical signal and the threshold range.

[0139] In this embodiment, when a finger is detected touching the corresponding fingerprint acquisition area of ​​the fingerprint module, it indicates that the user is performing fingerprint unlocking, or that the user's finger has accidentally touched the fingerprint acquisition area, or that the pressure-sensitive device itself is being activated. Since different operations generate different pressures, the user's true intention can be identified based on the electrical signal corresponding to the pressure generated by the finger touching the fingerprint module, and the corresponding operation can be executed. This effectively prevents accidental fingerprint unlocking, thus improving the user experience.

[0140] In an optional embodiment, step S1120, "performing different operations based on the comparison result of the electrical signal and the threshold range," specifically includes steps S1120-1 to S1120-3:

[0141] Step S1120-1: If the electrical signal is less than the minimum value of the threshold range, determine the fingerprint collection area that was accidentally touched.

[0142] Step S1120-2: When the electrical signal is within the range of the threshold, a fingerprint image is acquired by the fingerprint acquisition module.

[0143] Step S1120-3: If the electrical signal is greater than the maximum value of the threshold range, determine the function of turning on the power button.

[0144] In this embodiment, the threshold range is set based on the pressure generated by the actual unlocking action. Since different operations generate different pressures, the corresponding electrical signals are also different. When a user accidentally touches the fingerprint collection area, the pressure generated is smaller, and the corresponding electrical signal is also smaller. Therefore, when the electrical signal is less than the minimum value of the threshold range, it is determined that the user has accidentally touched the fingerprint collection area.

[0145] When a user needs to activate the power button (pressure-sensitive device), the pressure generated is greater, and the corresponding electrical signal is also greater. Therefore, when the electrical signal exceeds the maximum value of the threshold range, the power button function is activated.

[0146] When a user needs to unlock, the pressure generated is between accidental touch and activating the power button. Therefore, when the electrical signal is within the threshold range, it is determined that the user's true intention is to unlock, and at this time, the fingerprint acquisition module acquires a fingerprint image.

[0147] In this way, by comparing the electrical signal generated by the finger touching the fingerprint module in relation to the pressure with the threshold range, the user's true intention can be identified, thereby improving the user experience.

[0148] In an optional embodiment, step S1110, "detecting the electrical signal corresponding to pressure generated by the finger pressing the fingerprint module," specifically includes: measuring the charge change of the detection capacitor in the pressure-sensitive device; and generating an electrical signal corresponding to pressure based on the charge change.

[0149] In this embodiment, the pressure-sensitive device includes a detection capacitor composed of a first side electrode plate and a second side electrode plate. When a finger touches the fingerprint module, the charge between the first side electrode plate and the second side electrode plate of the pressure-sensitive device changes, and the pressure detection module generates an electrical signal corresponding to the pressure based on the charge change.

[0150] Specifically, based on the change in charge, an electrical signal corresponding to the pressure is generated, including steps A1 to A3:

[0151] Step A1: Charge the detection capacitor until the voltage of the detection capacitor equals the target voltage.

[0152] Step A2: Transfer the charge on the probe capacitor to the integrating capacitor in the integrator, so that the integrator outputs a voltage signal based on the charge transferred to the integrating capacitor.

[0153] Step A3: The voltage signal output by the integrator is processed by the signal processing module to obtain an electrical signal corresponding to the pressure.

[0154] In this embodiment, when a finger touches the fingerprint module, the capacitance of the sensing capacitor in the pressure-sensitive device changes with the magnitude of the pressure applied. At this time, by charging the sensing capacitor in the pressure-sensitive device, the change in capacitance will cause a change in the charge on the sensing capacitor. Therefore, the generation of an electrical signal corresponding to the pressure can be determined based on the charge on the sensing capacitor. That is, the charge on the sensing capacitor is transferred to the integrating capacitor in the integrator, so that the integrator outputs a voltage signal based on the charge transferred to the integrating capacitor, and the electrical signal corresponding to the pressure is obtained based on the voltage signal.

[0155] Specifically, the signal processing module includes an amplifier and an analog-to-digital converter; the signal processing module processes the voltage signal output by the integrator to obtain an electrical signal corresponding to the pressure, including: amplifying the voltage signal output by the integrator to a certain amplitude using the amplifier, converting the amplified voltage signal into a digital signal using the analog-to-digital converter, and finally obtaining an electrical signal corresponding to the pressure based on the digital signal.

[0156] This application provides various fingerprint acquisition devices, which are described below based on... Figure 2 neutralization Figure 5 The process of obtaining electrical signals corresponding to pressure using the two fingerprint acquisition devices shown is explained.

[0157] (1) Based on Figure 2 The fingerprint acquisition device shown obtains an electrical signal corresponding to the pressure:

[0158] Specifically, charging the detection capacitor includes steps B1 to B2:

[0159] Step B1: Close the first switch and open the second switch;

[0160] Step B2: After the first time interval, close the third switch to connect the line between the reference voltage and the detection capacitor, and charge the detection capacitor through the reference voltage.

[0161] For example, Figure 2 The pressure detection module of the fingerprint acquisition device shown is as follows: Figure 4 As shown, when a finger touches the fingerprint module, the first switch is closed and the second switch is opened to connect the circuit between the detection capacitor of the pressure-sensitive device and the pressure detection module. After a first time interval following the connection, the third switch is closed to charge the detection capacitor using a reference voltage.

[0162] Specifically, transferring the charge on the probe capacitor to the integrating capacitor includes steps C1 to C2:

[0163] Step C1: Disconnect the third switch and close the fourth switch to connect the circuit between the detection capacitor and the integrating capacitor in the integrator, and transfer the charge on the detection capacitor to the integrating capacitor in the integrator.

[0164] Step C2: Alternately close the third switch and the fourth switch to transfer the charge on the detection capacitor to the integrating capacitor in the integrator multiple times.

[0165] like Figure 4 As shown, after the probe capacitor has finished charging, the third switch is opened and the fourth switch is closed to transfer the charge on the probe capacitor to the integrating capacitor in the integrator. Furthermore, by alternately closing the third and fourth switches, the charge on the probe capacitor is transferred to the integrating capacitor in the integrator multiple times. This multiple charge accumulation increases the voltage signal strength, reduces drive noise, and thus improves the accuracy and signal-to-noise ratio of the voltage signal.

[0166] Furthermore, to obtain accurate pressure information, before transferring the charge on the sensing capacitor to the integrating capacitor in the integrator, the method further includes: closing the fifth switch to reset the integrating capacitor in the integrator, thereby resetting the potential of the integrating capacitor to 0. For example, as... Figure 4 The pressure detection module shown resets the integrating capacitor by closing the fifth switch. After resetting, the fifth switch needs to be opened to transfer the charge on the sensing capacitor to the integrating capacitor in the integrator.

[0167] In this embodiment of the application, the processor of the electronic device controls the on / off state of the switch by outputting a voltage (IOVDD) through an output pin. For example, Figure 12 This is a control timing diagram of a fingerprint acquisition device provided in an embodiment of this application, such as... Figure 12 As shown, when a finger touches the fingerprint module, firstly, a high-level signal is output to control the first and fifth switches to close, so as to reset the integrating capacitor in the integrator. After a first time interval, a high-level signal is used to close the third switch to connect the line between the reference voltage and the detection capacitor, so as to charge the detection capacitor through the reference voltage.

[0168] Next, a low-level signal (i.e., voltage 0) disconnects the third and fifth switches, while a high-level signal closes the fourth switch, connecting the circuit between the sensing capacitor and the integrating capacitor in the integrator, transferring the charge from the sensing capacitor to the integrating capacitor in the integrator. Then, the third and fourth switches are alternately closed, repeatedly transferring the charge from the sensing capacitor to the integrating capacitor in the integrator. Finally, based on the voltage signal output by the integrator, an electrical signal corresponding to the pressure is obtained.

[0169] (2) Based on Figure 5 The fingerprint acquisition device shown obtains an electrical signal corresponding to the pressure:

[0170] Specifically, charging the detection capacitor includes steps D1 to D2:

[0171] Step D1: Close the first and sixth switches, and open the second and seventh switches;

[0172] Step D2: After the first time interval, close the third switch to connect the line between the reference voltage and the detection capacitor, and charge the detection capacitor through the reference voltage.

[0173] For example, Figure 5 The pressure detection module of the fingerprint acquisition device shown is as follows: Figure 6 As shown, when a finger touches the fingerprint module, the first and sixth switches are closed, and the second and seventh switches are opened, connecting the line between the pressure-sensitive device's detection capacitor and the pressure detection module, and connecting the line between the pressure-sensitive device's detection capacitor and the driving voltage module; after a first time interval following the connection, the third switch is closed to charge the detection capacitor using a reference voltage.

[0174] Specifically, transferring the charge on the probe capacitor to the integrator includes steps E1 to E3:

[0175] Step E1: Disconnect the third switch and control the drive voltage module to generate a square wave signal to drive the second electrode plate of the probe capacitor;

[0176] Step E2: Close the fourth switch to connect the circuit between the detection capacitor and the integrating capacitor in the integrator, and transfer the charge of the detection capacitor to the integrating capacitor in the integrator.

[0177] Step E3: Alternately close the third switch and the fourth switch to transfer the charge on the detection capacitor to the integrating capacitor in the integrator multiple times.

[0178] like Figure 5 As shown, after the probe capacitor completes charging, the third switch is opened, and the drive voltage module is controlled to generate a square wave signal to drive the second electrode plate of the probe capacitor. At this time, the voltage of the first electrode plate of the probe capacitor is raised. Then, the fourth switch is closed to transfer the charge on the probe capacitor to the integrating capacitor in the integrator. Furthermore, by alternately closing the third and fourth switches, the charge on the probe capacitor is transferred to the integrating capacitor in the integrator multiple times. Through multiple charge accumulations, the voltage signal pressure is increased, the drive noise is reduced, and thus the accuracy and signal-to-noise ratio of the voltage signal are improved.

[0179] In this embodiment of the application, the processor of the electronic device controls the on / off state of the switch by outputting a voltage (IOVDD) through an output pin. For example, Figure 13 This is a control timing diagram of another fingerprint acquisition device provided in the embodiments of this application, such as... Figure 13 As shown, when a finger touches the fingerprint module, firstly, a high-level signal controls the first and sixth switches to close, as well as the fifth switch to close, thereby resetting the integrating capacitor in the integrator; after the first time interval, a high-level signal closes the third switch to connect the line between the reference voltage and the detection capacitor, thereby charging the detection capacitor with the reference voltage.

[0180] Subsequently, a low-level signal disconnects the third and fifth switches, while a high-level signal controls the fourth switch to close, thus connecting the circuit between the sensing capacitor and the integrating capacitor in the integrator, transferring the charge on the sensing capacitor to the integrating capacitor in the integrator. Next, the third and fourth switches are alternately closed, repeatedly transferring the charge from the sensing capacitor to the integrating capacitor in the integrator. In a preferred embodiment, the fourth switch is closed after a short delay following the opening of the third switch, ensuring that the two switches cannot conduct simultaneously. Finally, based on the voltage signal output by the integrator, an electrical signal corresponding to the pressure is obtained.

[0181] In this embodiment, a signal processing method is implemented based on a fingerprint acquisition device. This method determines the user's true intention based on the electrical signal corresponding to the pressure generated when a finger touches the fingerprint module. A fingerprint image is only acquired by the fingerprint acquisition device when a genuine unlocking fingerprint recognition action is performed, thus avoiding accidental unlocking fingerprint recognition and improving the user experience.

[0182] This application also provides an electronic device, see embodiments thereof. Figure 14 As shown, Figure 14 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device 1400 includes: a fingerprint acquisition device 1401 and a processor 1402 as described in this embodiment of the application. The processor 1402 generates control signals to switch the state of the switch in the fingerprint acquisition device 1401 and to perform fingerprint recognition based on the fingerprint image.

[0183] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0184] This application describes embodiments of a fingerprint acquisition device, signal processing method, and electronic device according to embodiments of this application with reference to flowchart illustrations and / or block diagrams. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the fingerprint acquisition device, signal processing method, and electronic device according to the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0185] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0186] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0187] The fingerprint acquisition device provided in this application has been described in detail above. Specific examples have been used to illustrate the principle and implementation of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​this application. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A fingerprint acquisition device, characterized by The switch comprises a first switch and / or a second switch, the first switch is electrically connected between the pressure sensing device and the fingerprint module, and the second switch is electrically connected between the pressure sensing device and the processor of the electronic device, and the capacitance of the pressure sensing device changes with the pressure received thereby. The fingerprint module is electrically connected to the processor of the electronic device, and the fingerprint module comprises a pressure detection module and a fingerprint acquisition module; the pressure detection module generates an electrical signal corresponding to the pressure when a finger contacts the fingerprint module, and the fingerprint acquisition module is used to acquire a fingerprint image. The pressure sensing device comprises a detection capacitor composed of a first side electrode plate and a second side electrode plate.

2. The fingerprint acquisition device of claim 1, wherein, 3. The fingerprint acquisition device according to claim 2, wherein The first switch and / or the second switch are switched in response to a control signal generated by the processor; In the case where the switch comprises the first switch and the second switch, one of the first switch and the second switch is in a closed state, and the other is in an open state.

4. The fingerprint acquisition device according to claim 3, wherein In the case where a finger contacts the surface of the fingerprint module, the first switch is in a closed state; In the case of a default state and a failed fingerprint identification, the second switch is in a closed state.

5. The fingerprint acquisition device according to claim 3, wherein A first end of the first switch is connected to the first side electrode plate of the detection capacitor, and a second end of the first switch is connected to an input end of the pressure detection module; A first end of the second switch is connected to the first side electrode plate of the detection capacitor, and a second end of the second switch is connected to an input end of the processor; A second side electrode plate of the detection capacitor is grounded. The pressure detection module comprises a third switch, a fourth switch, a fifth switch, an integrator, and a signal processing module; 6. The fingerprint acquisition device of claim 5, wherein, The second end of the first switch is connected to the input end of the pressure detection module, comprising that the second end of the first switch is respectively connected to the first end of the third switch and the first end of the fourth switch; The second end of the third switch is connected to a reference voltage; The fifth switch is connected in parallel with an integration capacitor of the integrator; An input end of the integrator is connected to the second end of the fourth switch, and an output end of the integrator is connected to an input end of the signal processing module.

7. The fingerprint acquisition device according to claim 1, wherein In the case where the switch comprises a first switch, the switch further comprises a sixth switch, the fingerprint module further comprises a driving voltage module, and the sixth switch is electrically connected between the driving voltage module and the pressure sensing device; In the case where the switch comprises a second switch, the switch further comprises a seventh switch, and the seventh switch is electrically connected between the pressure sensing device and a ground terminal. The first switch, the second switch, the sixth switch, and the seventh switch are switched in response to a control signal generated by the processor.

8. The fingerprint acquisition device of claim 7, wherein, ​ Wherein, in the case of the finger contacting the surface of the fingerprint module, the first switch and the sixth switch are in the closed state; in the case of the default state and the failure of fingerprint identification, the second switch and the seventh switch are in the closed state.

9. The fingerprint acquisition device of claim 8, wherein, The pressure sensing device comprises a detection capacitor composed of a first side electrode plate and a second side electrode plate; The first end of the sixth switch is connected to the output end of the driving voltage module, and the second end of the sixth switch is connected to the second side electrode plate of the detection capacitor; The first end of the seventh switch is grounded, and the second end of the seventh switch is connected to the second side electrode plate of the detection capacitor.

10. The fingerprint acquisition device according to any of claims 1-9, wherein, The fingerprint module further comprises a first multiplexing switch and a signal processing module; The output end of the pressure detection module is connected to the first input end of the first multiplexing switch, the output end of the fingerprint acquisition module is connected to the second input end of the first multiplexing switch, and the output end of the first multiplexing switch is connected to the input end of the signal processing module; The processor realizes the multiplexing of the pressure detection module and the fingerprint acquisition module to the signal processing module through the control of the first multiplexing switch.

11. The fingerprint acquisition device according to any of claims 1-9, wherein, The pressure sensing device is a power button of the electronic device.

12. The fingerprint acquisition device according to any of claims 1-9, wherein, The pressure sensing device is arranged between the fingerprint module and the power button of the electronic device, or the power button is arranged between the fingerprint module and the pressure sensing device.

13. The device according to any of claims 1-9, characterized in that The switch comprises the first switch and the second switch, the initial state of the first switch is the open state, and the initial state of the second switch is the closed state.

14. The device according to any of claims 1-9, characterized in that, Further comprising: A first circuit board; The pressure sensing device and the fingerprint module are connected through the first circuit board; The switch is arranged on the first circuit board.

15. The apparatus of claim 8, wherein, Further comprising: A second circuit board and a third circuit board; The pressure sensing device is arranged on the second circuit board, and the fingerprint module is arranged on the third circuit board; The first switch and the second switch are arranged on the second circuit board or the third circuit board, and the sixth switch and the seventh switch are arranged on the second circuit board or the third circuit board.

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