Fingerprint Detection Device and Electronic Device

Abstract

The present application provides a fingerprint detection device and an electronic device. The fingerprint detection device includes a fingerprint recognition system, a fingerprint detection module, and a boost module. The fingerprint recognition system is connected to the fingerprint detection module, the ground potential of the fingerprint detection module is connected to the ground potential of the fingerprint recognition system, and the boost module is used to output a target voltage. Among them, when the fingerprint detection module starts fingerprint scanning, starting from connecting the ground potential of the fingerprint recognition system to the external ground potential, the fingerprint detection module controls the output terminal of the boost module and the ground potential of the fingerprint recognition system to alternately connect to the external ground potential, so that the ground potential of the fingerprint detection module alternately changes between the external ground potential and the target voltage. Through the present application, the architecture design of the fingerprint detection device can be simplified, the relative floating of the ground potential of the fingerprint detection module and the ground potential of the fingerprint recognition system can be avoided, the signal strength of fingerprint detection can be improved, and the fingerprint detection effect can be improved.

Description

Technical Field

[0001] This application relates to the technical field of electronic devices, and particularly to a fingerprint detection device and an electronic device. Background Art

[0002] Currently, for the fingerprint detection function of electronic devices, the "floating ground" principle is usually adopted to configure the voltage of the fingerprint detection module to penetrate the glass cover plate. The "floating ground" principle means that the ground potential of the fingerprint detection module is raised or lowered as a whole, and the raised and lowered voltages are the excitation voltages of the fingerprint detection module.

[0003] In related technologies, a floating ground chip that implements the "floating ground" principle is configured between the fingerprint detection module and the algorithm chip. The floating ground chip is respectively configured with a communication port for the fingerprint detection module and the algorithm chip. The combination of these chips constitutes a fingerprint detection device. When the floating ground chip is working, it usually converts the voltages of the communication ports on both sides.

[0004] In this way, the overall device architecture for implementing the "floating ground" principle is relatively complex, and since the ground potential of the fingerprint detection module is different from the ground potential of the fingerprint recognition system, the ground potential of the fingerprint recognition system floats relatively, affecting the signal strength of fingerprint detection and thus the fingerprint detection effect. Summary of the Invention

[0005] This application aims to solve at least one of the technical problems in the related technologies to some extent.

[0006] To this end, this application proposes a fingerprint detection device and an electronic device, which can simplify the architecture design of the fingerprint detection device, avoid the relative floating of the ground potential of the fingerprint detection module and the ground potential of the fingerprint recognition system, improve the signal strength of fingerprint detection, and improve the fingerprint detection effect.

[0007] To achieve the above object, the fingerprint detection device proposed in the first aspect embodiment of this application includes: a fingerprint recognition system, a fingerprint detection module, and a boost module. The fingerprint recognition system is connected to the fingerprint detection module, the ground potential of the fingerprint detection module is connected to the ground potential of the fingerprint recognition system, and the boost module is used to output a target voltage. Wherein, when the fingerprint detection module starts to perform fingerprint scanning, starting from connecting the external ground potential with the ground potential of the fingerprint recognition system, the fingerprint detection module controls the output end of the boost module and the ground potential of the fingerprint recognition system to alternately connect to the external ground potential, so that the ground potential of the fingerprint detection module alternately changes between the external ground potential and the target voltage.

[0008] When the fingerprint detection device proposed in the first aspect embodiment of the present application starts fingerprint scanning, starting from connecting the external ground potential with the ground potential of the fingerprint recognition system, the fingerprint detection module controls the output terminal of the boost module and the ground potential of the fingerprint recognition system to alternately connect to the external ground potential, so that the ground potential of the fingerprint detection module alternately changes between the external ground potential and the target voltage. Since the ground potential of the fingerprint detection module is the same as the ground potential of the fingerprint recognition system, there is no need to set up a separate voltage conversion interface, thus simplifying the architecture design of the fingerprint detection device, avoiding the relative floating of the ground potential of the fingerprint detection module and the ground potential of the fingerprint recognition system, enhancing the signal strength of fingerprint detection, and improving the fingerprint detection effect.

[0009] To achieve the above object, the electronic device proposed in the second aspect embodiment of the present application includes: the fingerprint detection device proposed in the first aspect embodiment of the present application.

[0010] When the fingerprint detection module of the electronic device proposed in the second aspect embodiment of the present application starts fingerprint scanning, starting from connecting the external ground potential with the ground potential of the fingerprint recognition system, the fingerprint detection module controls the output terminal of the boost module and the ground potential of the fingerprint recognition system to alternately connect to the external ground potential, so that the ground potential of the fingerprint detection module alternately changes between the external ground potential and the target voltage. Since the ground potential of the fingerprint detection module is the same as the ground potential of the fingerprint recognition system, there is no need to set up a separate voltage conversion interface, thus simplifying the architecture design of the fingerprint detection device, avoiding the relative floating of the ground potential of the fingerprint detection module and the ground potential of the fingerprint recognition system, enhancing the signal strength of fingerprint detection, and improving the fingerprint detection effect.

[0011] The additional aspects and advantages of the present application will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present application. Description of the Drawings

[0012] The above and / or additional aspects and advantages of the present application will become obvious and easy to understand from the following description of the embodiments in conjunction with the drawings, where:

[0013] Figure 1 is a schematic structural diagram of a fingerprint detection device proposed in an embodiment of the present application;

[0014] Figure 2 is a schematic diagram of the fingerprint detection process in an embodiment of the present application;

[0015] Figure 3 is a schematic diagram of the positive excitation voltage waveform in an embodiment of the present application;

[0016] Figure 4 is a schematic diagram of the reverse excitation voltage waveform in an embodiment of the present application;

[0017] Figure 5 Schematic structural diagram of a fingerprint detection device according to another embodiment of the present application;

[0018] Figure 6 Schematic structural diagram of an electronic device according to an embodiment of the present application. Detailed implementation manners

[0019] Embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals indicate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as a limitation to the present application. On the contrary, the embodiments of the present application include all changes, modifications and equivalents that fall within the spirit and connotation of the appended claims.

[0020] Figure 1 Schematic structural diagram of a fingerprint detection device according to an embodiment of the present application.

[0021] Referring to Figure 1 , the fingerprint detection device 10 includes: a fingerprint detection module 101, a boosting module 102, and a fingerprint recognition system 103. The fingerprint recognition system 103 is connected to the fingerprint detection module 101, and the ground potential of the fingerprint detection module 101 is connected to the ground potential of the fingerprint recognition system 103. The boosting module 102 is used to output a target voltage. Wherein, when the fingerprint detection module 101 starts to perform fingerprint scanning, starting from connecting the ground potential of the fingerprint recognition system 103 to the external ground potential, the fingerprint detection module 101 controls the output terminal of the boosting module 102 and the ground potential of the fingerprint recognition system to alternately connect to the external ground potential, so that the ground potential of the fingerprint detection module 101 alternately changes between the external ground potential and the target voltage.

[0022] The above-mentioned target voltage is, for example, 30V, and the external ground potential is usually 0V.

[0023] In the present application, in two application scenarios where the ground potential of the fingerprint recognition system 103 is connected to the external ground potential, and where the fingerprint detection module 101 controls the boosting module 102 and the ground potential of the fingerprint recognition system to alternately connect to the external ground potential, the ground potential of the fingerprint detection module 101 and the ground potential of the fingerprint recognition system 103 both remain the same.

[0024] When the fingerprint detection module 101 detects whether a finger exists, the ground potential of the fingerprint recognition system 103 is connected to the external ground potential. At this time, the external ground potential is 0V, and the ground potential of the fingerprint recognition system 103 is also 0V. Since the ground potential of the fingerprint detection module 101 is the same as that of the fingerprint recognition system 103, the ground potential of the fingerprint detection module 101 is also 0V. Usually, the power output voltage value of the fingerprint detection module 101 is small (for example, 3V). Therefore, it can detect whether a finger exists based on a 3V voltage.

[0025] When the fingerprint detection module 101 detects a finger, the fingerprint detection module starts fingerprint scanning. The fingerprint detection module 101 controls the ground potential of the boost module 102 and the fingerprint recognition system 103 to alternately connect to the external ground potential, so that the ground potential of the fingerprint detection module 101 alternates between the external ground potential and the target voltage.

[0026] As an example, when the boost module 102 connects to the external ground potential, the external ground potential is 30V. At this time, since the power supply of the fingerprint detection module 101 is less than 30V (usually the power output voltage value of the fingerprint detection module 101 is 3V), a reverse excitation voltage (-27V) is formed between the output voltage of the fingerprint detection module 101 and the external ground potential of 30V. Thus, the fingerprint detection module 101 can scan the fingerprint image based on this reverse excitation voltage. This reverse excitation voltage (-27V) is sufficient to penetrate the glass cover plate covering the fingerprint detection module 101, thus ensuring the recognition accuracy.

[0027] As another example, if the above target voltage is, for example, -30V (generating a negative direction), and the external ground potential is usually 0V. When the boost module 102 connects to the external ground potential, the voltage value of the external ground potential is the same as that of the target voltage. For example, when the boost module 102 connects to the external ground potential, the external ground potential is -30V. At this time, since the power supply of the fingerprint detection module 101 is less than 30V (usually the power output voltage value of the fingerprint detection module 101 is 3V), a positive excitation voltage (+33V) is formed between the output voltage of the fingerprint detection module 101 and the external ground potential of -30V. Thus, the fingerprint detection module 101 can identify the fingerprint image based on this positive excitation voltage. This positive excitation voltage (+33V) is sufficient to penetrate the glass cover plate covering the fingerprint detection module 101, thus ensuring the recognition accuracy.

[0028] See also Figure 2 、 Figure 3 、 Figure 4 , Figure 2 is the schematic diagram of the fingerprint detection process in the embodiment of the present application, Figure 3 is the schematic diagram of the positive excitation voltage waveform in the embodiment of the present application, Figure 4It is a schematic diagram of the reverse excitation voltage waveform in the embodiments of the present application.

[0029] When identifying a fingerprint image based on the reverse excitation voltage, the ground potential of the fingerprint detection module 101 is the same as that of the fingerprint recognition system 103. Therefore, compared with the "floating ground" principle in the related art, the present application realizes "floating ground" for the overall fingerprint detection device 10, so that there is no need to configure a separate voltage conversion interface or circuit between the modules in the fingerprint detection device 10. While simplifying the architecture design of the fingerprint detection device, it avoids the relative floating of the ground potential of the fingerprint detection module and the ground potential of the fingerprint recognition system.

[0030] In some embodiments, referring to Figure 5 , the fingerprint detection device 10 further includes: a pixel module 104 connected to the fingerprint detection module. During the process of the alternating change of the ground potential of the fingerprint detection module 101, the fingerprint detection module 101 generates an excitation voltage; the fingerprint detection module 101 charges and discharges the pixel module 104 with the excitation voltage, thereby scanning the fingerprint image, improving the timeliness of fingerprint image scanning, and ensuring the scanning effect.

[0031] In some embodiments, referring to Figure 5 , the fingerprint detection device 10 further includes: a switch 105. One end of the switch 105 is connected to an external ground potential, and the other end of the switch 105 is selectively connected to the ground potential of the fingerprint recognition system 103 or the output end of the boost module 102. Among them, when the other end of the switch 105 is connected to the ground potential of the fingerprint recognition system 103, the ground potential of the fingerprint recognition system 103 is connected to the external ground potential; when the other end of the switch 105 is connected to the output end of the boost module 102, the output end of the boost module 102 is connected to the external ground potential.

[0032] In some embodiments, the fingerprint detection module 101 is further configured to detect whether a finger exists. If it exists, the fingerprint detection module starts fingerprint scanning. If not, the fingerprint detection module controls the ground potential of the fingerprint recognition system to be connected to the external ground potential, so as to realize that fingerprint scanning starts only when a finger is detected, which can effectively save the consumption of computing resources, avoid excessive power consumption, and improve the battery life of the electronic device equipped with the fingerprint detection module 101.

[0033] In some embodiments, when the fingerprint detection module 101 starts fingerprint scanning, it automatically controls the other end of the switch 105 to be selectively connected to the ground potential of the fingerprint recognition system 103 or the output end of the boost module 102, so as to control the output end of the boost module 102 and the ground potential of the fingerprint recognition system 103 to be alternately connected to the external ground potential, which can realize automatic ground potential switching, ensure the scanning effect, and improve the automation effect of fingerprint detection.

[0034] In some embodiments, after the fingerprint detection module 101 scans and obtains a fingerprint image, it sends the fingerprint image to the fingerprint recognition system 103, so that the fingerprint recognition system 103 can perform fingerprint recognition based on the fingerprint image, ensuring the continuity of fingerprint detection.

[0035] See the above Figure 5 , Figure 5 FIG. is a schematic structural diagram of a fingerprint detection device according to another embodiment of the present application, including a fingerprint detection module 101, a boost module 102, and a fingerprint recognition system. The fingerprint recognition system may specifically be, for example, a main control single-chip microcomputer 106. Data communication is performed between the fingerprint detection module 101 and the main control single-chip microcomputer 106. For example, when the fingerprint detection module 101 scans and obtains a fingerprint image, it can send the fingerprint image to the main control single-chip microcomputer 106, and the main control single-chip microcomputer 106 determines whether the fingerprint image matches a pre-stored fingerprint image. When the fingerprint detection module 101 detects the presence of a finger, it automatically controls the ground potential of the boost module 102 and the fingerprint recognition system to alternately connect to the external ground potential. While scanning and obtaining the fingerprint image, it automatically connects the ground potential of the fingerprint detection device 10 to the external ground potential.

[0036] See the above together Figure 5 , when the fingerprint detection module 101 controls the ground potential of the fingerprint recognition system 103 to connect to the external ground potential, Figure 5 the other end of the switch 105 in Figure 5 is connected to the ground potential of the fingerprint recognition system 103, which may be, for example, labeled 21. And when the fingerprint detection module 101 controls the output terminal of the boost module 102 to connect to the external ground potential,

[0037] the other end of the switch 105 in

[0038] is connected to the output terminal of the boost module 102, which may be, for example, labeled 22. Or, any other possible circuit form may also be adopted to control the output terminal of the boost module and the ground potential of the fingerprint recognition system to alternately connect to the external ground potential, and no limitation is made thereto. Figure 5 Figure 5 That is to say, see the above together

[0039]

[0039] Generally, a very high voltage is not required to penetrate the glass cover plate when scanning a fingerprint image. Therefore, in the embodiments of the present application, when it is detected that a finger exists, the ground potential of the boost module 102 and the fingerprint recognition system 103 can be controlled to alternately connect to the external ground potential, effectively assisting in generating a fingerprint image, and avoiding a large voltage difference between the fingerprint detection module 101 and the external ground potential for a long time, which can weaken the loss of the fingerprint detection module 101 and extend the service life of the fingerprint detection module 101.

[0040] As a more specific example, the ground potential of the overall fingerprint detection device 10 is raised or lowered to generate an excitation voltage for fingerprint image recognition. A boost module is used in the fingerprint detection device to generate a fixed high voltage, such as 30V. When the fingerprint detection module starts fingerprint scanning, the output terminal of the boost module and the ground potential of the fingerprint recognition system are controlled to alternately connect to the external ground potential.

[0041] When the ground potential of the fingerprint detection device is connected to the external ground potential, the ground potential of both the fingerprint detection module and the entire fingerprint detection device is connected to the external ground potential. At this time, the ground potential of the entire fingerprint detection device and the fingerprint detection module is 0V relative to the external ground potential, and the power supply of the fingerprint detection module is 3V relative to the external ground potential. Then, the switch is switched to connect the high-voltage module (assumed to be 30V) of the fingerprint detection device to the external ground potential. At this time, the ground potential of the entire fingerprint detection device is -30V relative to the external ground potential. Similarly, the ground potential of the fingerprint detection module is also -30V relative to the external ground potential, and the power supply of the fingerprint detection module is -27V.

[0042] That is to say, the entire fingerprint detection device is lowered by 30V relative to the external ground potential. At this time, the fingerprint detection module generates a 30V reverse excitation. Similarly, when the switch is switched from the ground potential of the high-voltage module connected to the external ground potential back to the ground potential of the fingerprint detection device connected to the external ground potential, the entire fingerprint detection device is raised from -30V to 0V. At this time, the fingerprint detection module realizes a 30V forward excitation.

[0043] Therefore, both the fingerprint detection module and the fingerprint recognition system of the present application are configured in the same fingerprint detection device, and the communication signals all refer to the ground potential of the fingerprint detection device. Therefore, it is not necessary to configure an additional voltage conversion circuit for voltage conversion. In addition, there is always a relatively definite voltage relationship between the ground potential of the fingerprint detection device and the external ground potential. Therefore, the excitation voltage will not decay, the signal strength is more stable, the signal-to-noise ratio is higher, the image quality is better, the fingerprint recognition effect is improved, and the user experience is enhanced.

[0044] In this embodiment, when the fingerprint detection module starts fingerprint scanning, starting from connecting the ground potential of the fingerprint recognition system to the external ground potential, the fingerprint detection module controls the output terminal of the boost module and the ground potential of the fingerprint recognition system to alternately connect to the external ground potential, so that the ground potential of the fingerprint detection module alternately changes between the external ground potential and the target voltage. Since the ground potential of the fingerprint detection module is the same as the ground potential of the fingerprint recognition system, there is no need to set up a separate voltage conversion interface, thereby simplifying the architecture design of the fingerprint detection device, avoiding the relative floating of the ground potential of the fingerprint detection module and the ground potential of the fingerprint recognition system, improving the signal strength of fingerprint detection, and enhancing the fingerprint detection effect.

[0045] Figure 6 It is a schematic structural diagram of an electronic device proposed in an embodiment of the present application.

[0046] See Figure 6 , the electronic device 600 includes:

[0047] The fingerprint detection device 10 in the above embodiment.

[0048] It should be noted that the explanations of the embodiments of the fingerprint detection device 10 in the foregoing Figures 1 - 5 embodiments are also applicable to the electronic device 600 in this embodiment. The implementation principles are similar and will not be elaborated here.

[0049] In this embodiment, when the fingerprint detection module starts fingerprint scanning, starting from connecting the ground potential of the fingerprint recognition system to the external ground potential, the fingerprint detection module controls the output terminal of the boost module and the ground potential of the fingerprint recognition system to alternately connect to the external ground potential, so that the ground potential of the fingerprint detection module alternately changes between the external ground potential and the target voltage. Since the ground potential of the fingerprint detection module is the same as the ground potential of the fingerprint recognition system, there is no need to set up a separate voltage conversion interface, thereby simplifying the architecture design of the fingerprint detection device, avoiding the relative floating of the ground potential of the fingerprint detection module and the ground potential of the fingerprint recognition system, improving the signal strength of fingerprint detection, and enhancing the fingerprint detection effect.

[0050] It should be noted that in the description of the present application, terms such as "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present application, unless otherwise specified, the meaning of "plurality" is two or more.

[0051] Any process or method description depicted in a flowchart or described otherwise herein can be understood to represent a module, segment, or portion of code that includes one or more executable instructions for implementing a specific logical function or process. The scope of the preferred embodiments of the present application includes additional implementations where functions may be executed not in the order shown or discussed, including in a substantially simultaneous manner according to the functions involved or in a reverse order, which should be understood by those skilled in the art to which the embodiments of the present application pertain.

[0052] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits with logic gate circuits for implementing logical functions on data signals, application specific integrated circuits with appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

[0053] Those of ordinary skill in the art of the present technology can understand that all or part of the steps carried out in implementing the above-described embodiment methods can be completed by instructing relevant hardware through a program. The said program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0054] In addition, in each embodiment of the present application, the functional units can be integrated into one processing module, or each unit can exist physically alone, or two or more units can be integrated into one module. The above-mentioned integrated modules can be implemented in the form of hardware or in the form of software functional modules. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0055] The above-mentioned storage medium can be a read-only memory, a magnetic disk, an optical disk, etc.

[0056] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0057] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A fingerprint detection device, characterized in that, The device includes: a fingerprint detection module, a boost module, and a fingerprint recognition system. The fingerprint recognition system is connected to the fingerprint detection module. The ground potential of the fingerprint detection module is connected to the ground potential of the fingerprint recognition system. The boost module is used to output a target voltage. Among them, When the fingerprint detection module starts fingerprint scanning, starting from connecting the ground potential of the fingerprint recognition system to the external ground potential, the fingerprint detection module controls the output terminal of the boost module and the ground potential of the fingerprint recognition system to alternately connect to the external ground potential, so that the ground potential of the fingerprint detection module alternately changes between the external ground potential and the target voltage.

2. The fingerprint detection device according to claim 1, characterized in that, The device further includes: a pixel module connected to the fingerprint detection module. During the process of the ground potential of the fingerprint detection module changing alternately, the fingerprint detection module generates an excitation voltage. The fingerprint detection module uses the excitation voltage to charge and discharge the pixel module, thereby scanning a fingerprint image.

3. The fingerprint detection device according to claim 1, characterized in that, The fingerprint detection module is further used to detect whether a finger exists. If it exists, the fingerprint detection module starts fingerprint scanning. If not, the fingerprint detection module controls the ground potential of the fingerprint recognition system to connect to the external ground potential.

4. The fingerprint detection device according to claim 2, characterized in that, The device further includes: a switch. One end of the switch is connected to the external ground potential, and the other end of the switch is selectively connected to the ground potential of the fingerprint recognition system or the output terminal of the boost module. Among them, When the other end of the switch is connected to the ground potential of the fingerprint recognition system, the ground potential of the fingerprint recognition system is connected to the external ground potential. When the other end of the switch is connected to the output terminal of the boost module, the output terminal of the boost module is connected to the external ground potential.

5. The fingerprint detection device according to claim 4, characterized in that, Among them, When starting fingerprint scanning, the fingerprint detection module automatically controls the other end of the switch to be selectively connected to the ground potential of the fingerprint recognition system or the output terminal of the boost module, thereby controlling the output terminal of the boost module and the ground potential of the fingerprint recognition system to alternately connect to the external ground potential.

6. The fingerprint detection device according to claim 2, characterized in that, Among them, After the fingerprint detection module scans and obtains a fingerprint image, it sends the fingerprint image to the fingerprint recognition system, and the fingerprint recognition system performs fingerprint recognition based on the fingerprint image.

7. The fingerprint detection device according to claim 2, characterized in that, Among them, While the fingerprint detection module scans and obtains a fingerprint image, it controls the ground potential of the fingerprint recognition system to connect to the external ground potential.

8. An electronic device, characterized in that, The electronic device includes the fingerprint detection device according to any one of claims 1-7 above.

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