Bluetooth non-inductive unlocking circuit

Abstract

The utility model discloses a Bluetooth non-inductive unlocking circuit which comprises a Bluetooth circuit and a second wireless communication circuit and is used for being wirelessly connected with Bluetooth equipment through the Bluetooth circuit. The second wireless communication circuit is connected with the Bluetooth circuit, the second wireless communication circuit is further used for being in wireless communication connection with an intelligent lock, and the Bluetooth device is further used for obtaining wireless signal strength information in wireless connection with the Bluetooth circuit and sending the wireless signal strength information to the intelligent lock when it is detected that the wireless signal strength information reaches a set value. And an unlocking instruction is sent to the intelligent lock through the Bluetooth circuit and the second wireless communication circuit, so that the intelligent lock is unlocked. In this way, automatic unlocking and locking operation of the intelligent lock can be achieved. When a user does not need to carry the remote controller or forgets to carry the remote controller, the lock can be unlocked and locked in a mobile phone Bluetooth mode, and use is very convenient for the user.

Description

Technical Field

[0001] The utility model relates to the technical field of intelligent lock circuits, and particularly relates to a Bluetooth passive unlocking circuit. Background Art

[0002] A remote control key is a key that uses the wireless remote control function of a central locking system to unlock and lock the vehicle remotely without inserting the key into the keyhole. In the application of two-wheel vehicles, the main function of the remote control key is to remotely control the vehicle lock. The working principle of the remote control for unlocking and locking the two-wheel vehicle is as follows: when the vehicle owner presses the button on the key, the key sends out a signal containing corresponding command information. The antenna on the two-wheel vehicle receives the radio wave signal, and after being authenticated by the body control module BCM, the actuator realizes the unlocking and locking actions.

[0003] The traditional remote control for two-wheel vehicles controls the vehicle's lock and unlock through 433M / 315M wireless signals. The remote control must be carried with the user at all times, otherwise the vehicle's lock and unlock cannot be controlled. Moreover, when locking and unlocking the vehicle, it is also necessary to press the control button to perform the unlocking and locking operations, which is relatively troublesome. Summary of the Utility Model

[0004] The utility model aims to at least solve one of the technical problems in the related art to some extent. For this reason, an object of the utility model is to propose a Bluetooth passive unlocking circuit.

[0005] To achieve the above object, according to an embodiment of the utility model, the Bluetooth passive unlocking circuit includes:

[0006] A Bluetooth circuit for wirelessly connecting with a Bluetooth device;

[0007] A second wireless communication circuit connected to the Bluetooth circuit and also used for wireless communication connection with an intelligent lock. The Bluetooth device is further used to obtain the wireless signal strength information of the wireless signal wirelessly connected to the Bluetooth circuit, and when detecting that the wireless signal strength information reaches a set value, send an unlocking instruction to the intelligent lock through the Bluetooth circuit and the second wireless communication circuit to perform an unlocking operation on the intelligent lock.

[0008] Further, according to an embodiment of the utility model, the second wireless communication circuit includes:

[0009] A wireless module antenna;

[0010] A wireless module filter circuit connected to the wireless module antenna to filter the signals received and transmitted by the wireless module antenna;

[0011] A wireless communication module, which is connected to the wireless module antenna through the wireless module filtering circuit to receive and transmit wireless signals.

[0012] Further, according to an embodiment of the present invention, the wireless module filtering circuit includes:

[0013] A receiving filtering circuit, one signal terminal of which is connected to the signal receiving terminal of the wireless communication module. The receiving filtering circuit is used to filter the received signal and convert the received signal into a differential signal, and then output it to the wireless communication module;

[0014] A transmitting filtering circuit, one signal terminal of which is connected to the signal transmitting terminal of the wireless communication module. The transmitting filtering circuit is used to filter and output the wireless signal output by the wireless communication module;

[0015] An antenna filtering circuit, one signal terminal of which is respectively connected to the wireless module antenna, and the other end of which is respectively connected to the other signal terminal of the receiving filtering circuit and the other signal terminal of the transmitting filtering circuit. The antenna filtering circuit is used to filter the input and output signals of the wireless module antenna.

[0016] Further, according to an embodiment of the present invention, the receiving filtering circuit includes:

[0017] A first inductor L4, one end of which is connected to the other end of the antenna filtering circuit, and the other end of which is connected to the first differential signal receiving terminal of the wireless communication module;

[0018] A first capacitor C27, one end of which is connected to the other end of the first inductor L4, and the other end of which is connected to the reference ground;

[0019] A second capacitor C26, one end of which is connected to the other end of the antenna filtering circuit, and the other end of which is connected to the second differential signal receiving terminal of the wireless communication module;

[0020] A second inductor L2, one end of which is connected to the other end of the second capacitor C26, and the other end of which is connected to the reference ground;

[0021] A third inductor L3, one end of which is connected to the first differential signal receiving terminal of the wireless communication module, and the other end of which is connected to the second differential signal receiving terminal of the wireless communication module.

[0022] Further, according to an embodiment of the present invention, the Bluetooth passive unlocking circuit further includes:

[0023] A power data interface for connecting a charging device;

[0024] A battery for supplying power to the Bluetooth circuit and the second wireless communication circuit;

[0025] A battery charging circuit, the power data interface is connected to the battery through the battery charging circuit to charge the battery through the battery charging circuit.

[0026] Further, according to an embodiment of the present invention, the Bluetooth passive unlocking circuit further includes:

[0027] A power supply circuit, the power input end of the power supply circuit is connected to the battery output end, and the output end of the power supply circuit is connected to the power supply end of the Bluetooth circuit, for converting the battery output power after voltage conversion to supply power to the Bluetooth circuit.

[0028] Further, according to an embodiment of the present invention, the Bluetooth passive unlocking circuit further includes:

[0029] An automatic reset circuit, the automatic reset circuit includes a reset controller, the signal input end of the reset controller is connected to the signal output end of the Bluetooth circuit, the output end of the automatic reset circuit is connected to the enable end of the power supply circuit, and the reset controller is used to control the power supply circuit to reset the Bluetooth circuit when it detects that the Bluetooth circuit is not working properly.

[0030] Further, according to an embodiment of the present invention, the Bluetooth passive unlocking circuit further includes:

[0031] A power supply control circuit, the power input end of the power supply control circuit is connected to the power output end of the power supply circuit, the output end of the power supply circuit is connected to the second wireless communication circuit, and the control end of the power supply control circuit is connected to a control end of the Bluetooth circuit, for controlling the conduction or disconnection of the power supply to the second wireless communication circuit under the control of the Bluetooth circuit.

[0032] Further, according to an embodiment of the present invention, the power supply control circuit includes:

[0033] MOS transistor Q1, the source electrode of the MOS transistor Q1 is connected to the power output end of the power supply circuit, the source electrode of the MOS transistor Q1 is also connected to the gate electrode of the MOS transistor Q1 through a first resistor R23, and the drain electrode of the MOS transistor Q1 is connected to the power supply end of the second wireless communication circuit;

[0034] A triode Q2, the collector of the triode Q2 is connected to the gate of the MOS transistor Q1 through a second resistor R27, the emitter of the triode Q2 is connected to the reference ground, and the base of the triode Q2 is connected to the one control terminal of the Bluetooth circuit through a third resistor R24.

[0035] Furthermore, according to an embodiment of the present invention, the wireless communication module is a 433MHz and / or 315M wireless module.

[0036] The Bluetooth passive unlocking circuit provided by the embodiment of the present invention is used for wirelessly connecting with a Bluetooth device through a Bluetooth circuit; a second wireless communication circuit is connected to the Bluetooth circuit, and the second wireless communication circuit is also used for wirelessly communicating with an intelligent lock. The Bluetooth device is further used for acquiring wireless signal strength information of the wireless connection with the Bluetooth circuit, and when detecting that the wireless signal strength information reaches a set value, sending an unlocking instruction to the intelligent lock through the Bluetooth circuit and the second wireless communication circuit to perform an unlocking operation on the intelligent lock. In this way, automatic unlocking and locking operations of the intelligent lock can be realized. When the user does not need to carry a remote control or forgets to bring a remote control, the user can perform locking and unlocking through the mobile phone Bluetooth method, which is very convenient for the user to use. Description of the Drawings

[0037] Figure 1 It is a structural block diagram of the Bluetooth passive unlocking circuit provided by the present invention;

[0038] Figure 2 It is a schematic structural diagram of the Bluetooth circuit provided by the present invention;

[0039] Figure 3 It is a schematic structural diagram of the second wireless communication circuit provided by the present invention;

[0040] Figure 4 It is a schematic structural diagram of the power data interface and the battery charging circuit provided by the present invention;

[0041] Figure 5 It is a schematic structural diagram of the automatic reset circuit and the power supply circuit provided by the present invention;

[0042] Figure 6 It is a schematic structural diagram of the power supply control circuit provided by the present invention.

[0043] The realization, functional characteristics and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Detailed Embodiments

[0044] To enable those skilled in the art to better understand the solutions of the present utility model, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present utility model belongs. The terms used in the description of the present utility model in this specification are only for the purpose of describing specific embodiments and are not intended to limit the present utility model.

[0045] Reference to "embodiment" herein means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present utility model. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

[0046] Referring to Figures 1 to 3 , an embodiment of the present utility model provides a Bluetooth passive unlocking circuit, including: a Bluetooth circuit and a second wireless communication circuit. The Bluetooth circuit is used for wireless connection with a Bluetooth device; the second wireless communication circuit is connected to the Bluetooth circuit, and the second wireless communication circuit is also used for wireless communication connection with a smart lock. The Bluetooth device is further used for obtaining wireless signal strength information of the wireless connection with the Bluetooth circuit, and when detecting that the wireless signal strength information reaches a set value, sending an unlocking instruction to the smart lock through the Bluetooth circuit and the second wireless communication circuit to perform an unlocking operation on the smart lock.

[0047] Specifically, as Figure 2As shown in the figure, the Bluetooth circuit includes a Bluetooth chip U1 and its peripheral circuit. The Bluetooth chip U1 is wirelessly connected to a Bluetooth device through a Bluetooth antenna J1. Among them, the Bluetooth device can be various mobile electronic devices with Bluetooth communication, such as a smart phone, a tablet computer, etc. When the user approaches the Bluetooth passive unlocking circuit by carrying various mobile electronic devices such as a smart phone, the Bluetooth chip U1 can establish a Bluetooth connection with the mobile electronic device such as a smart phone through the Bluetooth antenna J1. In this way, the smart phone can obtain the RSSI intensity value of the Bluetooth signal. Since an application APP is installed on the smart phone, when the user approaches the vehicle, the RSSI intensity value of the Bluetooth signal will gradually increase. When the RSSI intensity value of the Bluetooth signal reaches the unlocking threshold, the smart phone can output an unlocking instruction to the Bluetooth circuit, and the Bluetooth circuit and / or the Bluetooth circuit is wirelessly connected to the smart lock through a second wireless communication circuit, so as to control the unlocking of the smart lock. In this way, an operation-free automatic unlocking application can be realized, which is more convenient to use. On the contrary, when the user moves away from the vehicle, the RSSI intensity value of the Bluetooth signal will gradually decrease. When the RSSI intensity value of the Bluetooth signal decreases to less than the unlocking threshold, the smart phone can output a locking instruction to the Bluetooth circuit, and the Bluetooth circuit and / or the Bluetooth circuit is wirelessly connected to the smart lock through a second wireless communication circuit, so as to control the locking of the smart lock. In this way, the automatic unlocking and locking operations of the smart lock can be realized. When the user does not need to carry a remote control or forgets to bring a remote control, the user can lock and unlock the door through the mobile phone, which is very convenient for the user to use.

[0048] Referring to Figure 3 , the second wireless communication circuit includes: a wireless module antenna, a wireless module filtering circuit, and a wireless communication module. The wireless module filtering circuit is connected to the wireless module antenna to filter the signals received and transmitted by the wireless module antenna; the wireless communication module is connected to the wireless module antenna through the wireless module filtering circuit to receive and transmit wireless signals. As Figure 3As shown in the figure, the wireless module filtering circuit includes: a receiving filtering circuit, a transmitting filtering circuit, and an antenna filtering circuit. One signal terminal of the receiving filtering circuit is connected to the signal receiving terminal of the wireless communication module. The receiving filtering circuit is used to filter the received signal and convert the received signal into a differential signal, and then output it to the wireless communication module. One signal terminal of the transmitting filtering circuit is connected to the signal transmitting terminal of the wireless communication module. The transmitting filtering circuit is used to filter and output the wireless signal output by the wireless communication module. One signal terminal of the antenna filtering circuit is respectively connected to the wireless module antenna, and the other end of the antenna filtering circuit is respectively connected to the other signal terminal of the receiving filtering circuit and the other signal terminal of the transmitting filtering circuit. The antenna filtering circuit is used to filter the input and output signals of the wireless module antenna. Further, in an embodiment of the present invention, the wireless communication module is a 433 MHz and / or 315 M wireless module.

[0049] Among them, as Figure 3 shown in the figure, the receiving filtering circuit includes: a first inductor L4, a first capacitor C27, a second capacitor C26, a second inductor L2, and a third inductor L3. One end of the first inductor L4 is connected to the other end of the antenna filtering circuit, and the other end of the first inductor L4 is connected to the first differential signal receiving terminal of the wireless communication module. One end of the first capacitor C27 is connected to the other end of the first inductor L4, and the other end of the first capacitor C27 is connected to the reference ground. One end of the second capacitor C26 is connected to the other end of the antenna filtering circuit, and the other end of the second capacitor C26 is connected to the second differential signal receiving terminal of the wireless communication module. One end of the second inductor L2 is connected to the other end of the second capacitor C26, and the other end of the second inductor L2 is connected to the reference ground. One end of the third inductor L3 is connected to the first differential signal receiving terminal of the wireless communication module, and the other end of the third inductor L3 is connected to the second differential signal receiving terminal of the wireless communication module.

[0050] Specifically, a balun filter circuit for balanced-unbalanced conversion can be formed among the first inductor L4, the first capacitor C27, the second capacitor C26, the second inductor L2, and the third inductor L3. The unbalanced signal terminal of the balun filter circuit is connected to the single-ended signal received and output by the antenna. After the radio frequency signal enters the balun filter circuit, it is divided into two paths. One path is filtered by the filter circuit formed by the first inductor L4 and the first capacitor C27 and then output. The other path is filtered by the filter circuit of the second capacitor C26 and the second inductor L2 and then output. The two output signals are differential signals with opposite polarities. After further matching through the inductor L3, the differential signal is output to the wireless signal receiving end of the wireless communication module U5. Since the wireless signal input end of the wireless communication module U5 is a differential signal input and the antenna used is an unbalanced monopole antenna, a balun matching circuit must be used to match the radio frequency transceiver signals. In this embodiment, balun components are directly used for filtering and matching, so that the signal can be more completely output to the wireless signal receiving end of the wireless communication module U5.

[0051] Among them, as Figure 3 shown in, the antenna filter circuit may include an inductor L5, a capacitor C36, and an inductor L6. One end of the inductor L5 is connected to the signal output end of the wireless module antenna. The other end of the inductor L5 is connected to one end of the capacitor C36. The other end of the capacitor C36 is connected to the reference ground. The said one end of the capacitor C36 is connected to one end of the inductor L6. The other end of the inductor L6 is respectively connected to the signal input ends of the receiving filter circuit and the transmitting filter circuit. The inductor L5, the capacitor C36, and the inductor L6 form a T-type filter circuit, which can filter out the radio frequency interference signals introduced by the antenna and ensure the stability of the radio frequency signals input to the receiving filter circuit and the transmitting filter circuit.

[0052] Among them, as Figure 3 shown in, the transmitting filter circuit includes a capacitor C32, a capacitor C37, an inductor L7, and a capacitor C33. One end of the capacitor C32 is connected to the signal output end of the antenna filter circuit. The other end of the capacitor C32 is connected to one end of the capacitor C37. The other end of the capacitor C37 is connected to the reference ground. The said one end of the capacitor C37 is also connected to one end of the inductor L7. The other end of the inductor L7 is connected to one end of the capacitor C33. The other end of the capacitor C33 is connected to the wireless signal transmitting end of the wireless communication module U5. The capacitor C32, the capacitor C37, the inductor L7, and the capacitor C33 form a band-pass filter circuit, which can filter out the interfering radio frequency signals and low-frequency DC signals and ensure the reliability of the signals input to the wireless communication module U5.

[0053] Refer to Figure 1 and Figure 4, the Bluetooth passive unlocking circuit further includes: a power data interface, a battery, and a battery charging circuit. The power data interface is used to connect to a charging device; the battery is used to supply power to the Bluetooth circuit and the second wireless communication circuit; the power data interface is connected to the battery through the battery charging circuit to charge the battery through the battery charging circuit. As Figure 4 shown, the power data interface can be a Type-c USB interface. In this way, a charger with a USB interface can be connected, and the power supply can be introduced by connecting the USB interface. The battery charging circuit may include a charging control chip U4. Through the charging control chip U4, the introduced power can be voltage-converted to charge the battery J4. At the same time, the battery J4 can supply power to the power supply circuit module.

[0054] Refer to Figure 1 and Figure 5 , the Bluetooth passive unlocking circuit further includes: a power supply circuit. The power input terminal of the power supply circuit is connected to the battery output terminal, and the output terminal of the power supply circuit is connected to the power supply terminal of the Bluetooth circuit, and is used to convert the voltage of the battery output power to supply power to the Bluetooth circuit. As Figure 5 shown, the power supply circuit includes a voltage converter U2. Through the voltage converter U2, the battery output power VBAT can be voltage-converted to make the voltage meet the power supply requirements of the Bluetooth circuit.

[0055] Refer to Figure 1 and Figure 5, the Bluetooth passive unlocking circuit further includes: an automatic reset circuit, which includes a reset controller U3. The signal input end of the reset controller U3 is connected to the signal output end of the Bluetooth circuit, and the output end of the automatic reset circuit is connected to the enable end of the power supply circuit. The reset controller U3 is used to control the power supply circuit to reset the Bluetooth chip U1 when it detects that the Bluetooth chip U1 is not working properly. Since the Bluetooth circuit may experience a deadlock problem during operation. When the Bluetooth circuit is in a deadlock state, it cannot wirelessly communicate with Bluetooth devices such as smartphones. Therefore, at this time, the Bluetooth chip U1 needs to be reset through the automatic reset circuit. The reset controller U3 is connected to the Bluetooth chip U1 through the WDI signal terminal. When the Bluetooth chip U1 is working properly, it can output a signal to the reset controller U3 through the WDI signal terminal. When the reset controller U3 detects the signal, it can determine that the Bluetooth chip U1 is in a normal working state, otherwise the Bluetooth chip U1 is in a deadlock state. At this time, the reset controller U3 can output a low-level signal to the enable end of the voltage converter U2 to turn off the power supply output of the voltage converter U2, and the Bluetooth chip U1 shuts down due to lack of power supply. At this time, the reset controller U3 can output a high level and make the voltage converter U2 continue to supply power normally. In this way, the Bluetooth chip U1 can be restarted and enter the normal working state.

[0056] Refer to Figure 1 and Figure 6 , the Bluetooth passive unlocking circuit further includes: a power supply control circuit. The power input end of the power supply control circuit is connected to the power output end of the power supply circuit. The output end of the power supply circuit is connected to the second wireless communication circuit. The control end of the power supply control circuit is connected to a control end of the Bluetooth circuit, and is used to control the conduction or disconnection of the power supply to the second wireless communication circuit under the control of the Bluetooth circuit. Through the power supply control circuit, when the wireless communication module is not needed, the power supply can be disconnected, so as to achieve the purpose of saving battery power. When the Bluetooth circuit receives an unlocking instruction sent by a Bluetooth device, the wireless communication module is then turned on to unlock. In this way, the battery loss can be greatly reduced. As Figure 6 shown in, the power supply control circuit includes: an MOS transistor Q1 and a triode Q2. The source electrode of the MOS transistor Q1 is connected to the power output end of the power supply circuit. The source electrode of the MOS transistor Q1 is also connected to the gate electrode of the MOS transistor Q1 through a first resistor R23. The drain electrode of the MOS transistor Q1 is connected to the power supply end of the second wireless communication circuit. The collector electrode of the triode Q2 is connected to the gate electrode of the MOS transistor Q1 through a second resistor R27. The emitter electrode of the triode Q2 is connected to the reference ground. The base electrode of the triode Q2 is connected to the one control end of the Bluetooth circuit through a third resistor R24.

[0057] Specifically, the working process of the power supply control circuit is as follows. When the Bluetooth chip U1 does not need to perform unlocking or locking operations on the intelligent lock through the wireless communication module, it can output a low level through the P00_PWR_CRT signal terminal. This low level can cause the triode Q2 to cut off, and at the same time, it can also cause the MOS transistor Q1 to cut off. At this time, the power supply RF_3V3 has no power supply output, and the second wireless communication circuit stops working. On the contrary, when the Bluetooth chip U1 needs to perform unlocking or locking operations on the intelligent lock through the second wireless communication circuit, it can output a high level through the P00_PWR_CRT signal terminal. This high level can cause the triode Q2 to conduct, and at the same time, it can also cause the MOS transistor Q1 to conduct. At this time, the power supply RF_3V3 outputs power supply, the second wireless communication circuit starts to work, and communicates with the Bluetooth chip U1, and can perform unlocking or locking operations under the control of the Bluetooth chip U1.

[0058] The above are only the embodiments of the present invention, but do not limit the patent scope of the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing specific embodiments, or perform equivalent replacements for some of the technical features. Any equivalent structures made by using the content of the specification and drawings of the present invention, directly or indirectly applied in other related technical fields, are equally within the scope of the patent protection of the present invention.

[0059] In the description of this specification, the descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean 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 invention. 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 any one or more embodiments or examples in a suitable manner.

[0060] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, replacements, and variations to the above embodiments within the scope of the present invention without departing from the principles and purposes of the present invention, and all are within the protection scope of the present invention.

Claims

1. A Bluetooth passive unlocking circuit, characterized in that Including: A Bluetooth circuit for wireless connection with a Bluetooth device; A second wireless communication circuit connected to the Bluetooth circuit. The second wireless communication circuit is also used for wireless communication connection with an intelligent lock. The Bluetooth device is further used for obtaining wireless signal strength information of the wireless connection with the Bluetooth circuit, and when detecting that the wireless signal strength information reaches a set value, sending an unlocking instruction to the intelligent lock through the Bluetooth circuit and the second wireless communication circuit to perform an unlocking operation on the intelligent lock.

2. The Bluetooth passive unlocking circuit according to claim 1, wherein The second wireless communication circuit includes: A wireless module antenna; A wireless module filtering circuit connected to the wireless module antenna to filter the signals received and transmitted by the wireless module antenna; A wireless communication module connected to the wireless module antenna through the wireless module filtering circuit to receive and transmit wireless signals.

3. The Bluetooth passive unlocking circuit according to claim 2, characterized in that, The wireless module filtering circuit includes: A receiving filtering circuit. One signal terminal of the receiving filtering circuit is connected to the signal receiving terminal of the wireless communication module. The receiving filtering circuit is used for filtering the received signal and converting the received signal into a differential signal and then outputting it to the wireless communication module; A transmitting filtering circuit. One signal terminal of the transmitting filtering circuit is connected to the signal transmitting terminal of the wireless communication module. The transmitting filtering circuit is used for filtering and outputting the wireless signal output by the wireless communication module; An antenna filtering circuit. One signal terminal of the antenna filtering circuit is respectively connected to the wireless module antenna, and the other end of the antenna filtering circuit is respectively connected to the other signal terminal of the receiving filtering circuit and the other signal terminal of the transmitting filtering circuit. The antenna filtering circuit is used for filtering the input and output signals of the wireless module antenna.

4. The Bluetooth passive unlocking circuit according to claim 3, wherein, The receiving filtering circuit includes: A first inductor (L4). One end of the first inductor (L4) is connected to the other end of the antenna filtering circuit, and the other end of the first inductor (L4) is connected to the first differential signal receiving terminal of the wireless communication module; A first capacitor (C27). One end of the first capacitor (C27) is connected to the other end of the first inductor (L4), and the other end of the first capacitor (C27) is connected to the reference ground; A second capacitor (C26). One end of the second capacitor (C26) is connected to the other end of the antenna filtering circuit, and the other end of the second capacitor (C26) is connected to the second differential signal receiving terminal of the wireless communication module; A second inductor (L2). One end of the second inductor (L2) is connected to the other end of the second capacitor (C26), and the other end of the second inductor (L2) is connected to the reference ground; A third inductor (L3). One end of the third inductor (L3) is connected to the first differential signal receiving terminal of the wireless communication module, and the other end of the third inductor (L3) is connected to the second differential signal receiving terminal of the wireless communication module.

5. The Bluetooth passive unlocking circuit according to any one of claims 1 to 4, characterized in that It further includes: A power data interface for connecting a charging device; A battery for powering the Bluetooth circuit and the second wireless communication circuit; A battery charging circuit, wherein the power data interface is connected to the battery through the battery charging circuit to charge the battery through the battery charging circuit.

6. The Bluetooth passive unlocking circuit according to claim 5, wherein, Further comprising: A power supply circuit, wherein a power input end of the power supply circuit is connected to an output end of the battery, and an output end of the power supply circuit is connected to a power supply end of the Bluetooth circuit, for converting the output power of the battery and then supplying power to the Bluetooth circuit.

7. The Bluetooth passive unlocking circuit according to claim 6, wherein, Further comprising: An automatic reset circuit, wherein the automatic reset circuit includes a reset controller, a signal input end of the reset controller is connected to a signal output end of the Bluetooth circuit, an output end of the automatic reset circuit is connected to an enable end of the power supply circuit, and the reset controller is configured to control the power supply circuit to reset the Bluetooth circuit when detecting that the Bluetooth circuit is not working properly.

8. The Bluetooth passive unlocking circuit according to claim 6 or 7, characterized in that, Further comprising: A power supply control circuit, wherein a power input end of the power supply control circuit is connected to a power output end of the power supply circuit, an output end of the power supply circuit is connected to the second wireless communication circuit, and a control end of the power supply control circuit is connected to a control end of the Bluetooth circuit, for controlling conduction or disconnection of the power supply to the second wireless communication circuit under the control of the Bluetooth circuit.

9. The Bluetooth passive unlocking circuit according to claim 8, wherein, The power supply control circuit includes: A MOS transistor (Q1), a source electrode of the MOS transistor (Q1) is connected to the power output end of the power supply circuit, the source electrode of the MOS transistor (Q1) is further connected to a gate electrode of the MOS transistor (Q1) through a first resistor (R23), and a drain electrode of the MOS transistor (Q1) is connected to the power supply end of the second wireless communication circuit; A triode (Q2), a collector electrode of the triode (Q2) is connected to the gate electrode of the MOS transistor (Q1) through a second resistor (R27), an emitter electrode of the triode (Q2) is connected to a reference ground, and a base electrode of the triode (Q2) is connected to the control end of the Bluetooth circuit through a third resistor (R24).

10. The Bluetooth passive unlocking circuit according to any one of claims 2 to 4, characterized in that, The wireless communication module is a 433 MHz and / or 315 M wireless module.

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