Touch control circuit and intelligent door lock

Abstract

The utility model discloses a touch circuit and an intelligent door lock. The touch control circuit comprises a touch main control chip, a plurality of touch keys and a plurality of LED chips, wherein the touch keys and the LED chips are connected with the touch main control chip. The touch main control chip comprises a plurality of touch key detection units, a plurality of LED driving units, a lithium battery voltage detection unit, a low-voltage alarm unit, a communication interface unit and a low-power consumption mode processing unit; the touch key detection units and the LED driving units are combined in a one-to-one mode, and a universal input and output pin is reused. The general input / output pin is connected with the touch key and the anode of the LED chip after passing through a resistor, and the cathode of the LED chip is grounded. The touch control circuit adopts a touch control detection and LED display multiplexing design, so that port resources of a lock control chip are greatly saved. The touch control circuit has a sleep mode and can be used as an awakening device of the intelligent door lock, so that sleep power consumption is greatly reduced.

Description

Technical Field

[0001] The utility model relates to the field of intelligent door locks, and in particular to a touch circuit and an intelligent door lock. Background Art

[0002] With the rapid development of smart homes, smart door locks are being used more and more widely. Using smart door locks can save the trouble of carrying keys when going out while ensuring safety. At the same time, the locking and unlocking operations are also simpler. Using smart door locks can greatly improve the convenience of people's lives.

[0003] At present, most smart door locks use built-in batteries to power the operation of smart door locks. The built-in batteries can be dry batteries or lithium batteries. During the operation of smart door locks, the smart door locks are awakened by a fixed high interrupt wake-up frequency. However, practice has found that waking up the smart door locks with a fixed high interrupt wake-up frequency will result in high power consumption and short battery life due to the high wake-up frequency of the smart door locks; reducing the interrupt wake-up frequency of the smart door locks will slow down the response of the smart door locks and reduce the user experience.

[0004] The existing technology has two main shortcomings:

[0005] Low integration: The touch circuit only performs touch button detection functions, and LED light control and other functions require resources to be allocated by the lock control chip.

[0006] Poor adaptability: The common problem of false touch of touch buttons on smart door locks is mainly due to the return of the south wind in the south, when the humidity in the air is high, which affects the dielectric constant between the touch chips.

[0007] High power consumption in sleep mode: When the smart door lock is in sleep mode, the touch circuit and the lock control end (LPCD card swiping) need to enter low power consumption detection together. Utility Model Content

[0008] In order to solve one of the above problems in the prior art, the utility model provides a touch control circuit, and the technical solution is as follows:

[0009] A touch control circuit comprises a touch main control chip, and a plurality of touch buttons and a plurality of LED chips connected to the touch main control chip;

[0010] The touch main control chip includes multiple touch button detection units, multiple LED driving units, a lithium battery voltage detection unit, a low voltage alarm unit, a communication interface unit and a low power mode processing unit;

[0011] The touch button detection unit and the LED driving unit are combined one-to-one, and a universal input and output pin is reused; the universal input and output pin is connected to the touch button and the anode of the LED chip through a resistor, and the cathode of the LED chip is grounded;

[0012] The lithium battery voltage detection unit is directly or indirectly connected to the positive electrode of the battery to collect the battery voltage;

[0013] The low voltage alarm unit is used to output a low voltage alarm signal;

[0014] The low power consumption mode processing unit is used to control the touch main control chip to enter and exit the low power consumption mode;

[0015] The communication interface unit is used for communication connection with the outside.

[0016] Furthermore, the operating voltage of the touch main control chip is 3.3V, and the allowable input voltage of the lithium battery voltage detection unit is greater than 5V.

[0017] Furthermore, the communication interface unit of the touch main control chip is an I2C interface unit.

[0018] Furthermore, the number of the touch buttons is 14.

[0019] Furthermore, the touch control circuit also includes a humidity sensor connected to the touch main control chip.

[0020] In order to solve one of the above problems of the prior art, the utility model also provides a smart door lock, and the technical solution is as follows:

[0021] A smart door lock, characterized in that it includes a lock control circuit and the touch control circuit as described above, and the lock control circuit and the touch control circuit are communicatively connected.

[0022] Furthermore, the smart door lock is powered by a lithium battery or at least three dry batteries.

[0023] Furthermore, the smart door lock also includes a radio frequency identification card reader connected to the lock control circuit.

[0024] Furthermore, the smart door lock also includes a biometric identification device connected to the lock control circuit.

[0025] Furthermore, the biometric recognition device includes at least one of a fingerprint recognition device, a face recognition device, an iris recognition device, and a voiceprint recognition device.

[0026] Based on the above technical solution, the utility model can achieve the following technical effects:

[0027] The touch control circuit adopts the touch detection and LED display multiplexing design, which greatly saves the port resources of the lock control chip.

[0028] The touch control circuit integrates a humidity sensor, which can solve the problem of accidental touch of touch buttons in high humidity environments.

[0029] The touch control circuit has a sleep mode and can be used as a wake-up device for the smart door lock. The lock control circuit and the identity recognition device can be woken up by the touch control circuit, thereby greatly reducing sleep power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a functional block diagram of the intelligent door lock of the utility model;

[0031] Figure 2 It is a circuit principle diagram of the touch control circuit of the utility model. DETAILED DESCRIPTION

[0032] To further illustrate the various embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, a person of ordinary skill in the art should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0033] The utility model is now further described in conjunction with the accompanying drawings and specific implementation methods.

[0034] like Figure 1 and Figure 2 As shown, the utility model provides a smart door lock, which is composed of a lock control circuit 10, an identity recognition device 20 and a touch circuit 30. Among them, the touch circuit 30 includes a touch main control chip 310, and multiple touch buttons 320 and multiple LED chips 330 connected to the touch main control chip 310. The touch circuit 30 is integrated on a circuit board, which is set on the panel of the smart door lock to facilitate touch operation.

[0035] The touch control chip 310 can use a microprocessor, or a touch control chip with a built-in microprocessor, and can be independently programmed. The touch control chip 310 is based on the internal digital input and output unit, analog-to-digital conversion unit, comparator unit, storage unit, calculation unit and other hardware circuit units, and defines a variety of functional units through the combination of software and hardware, including multiple touch button detection units 311, multiple LED drive units 312, lithium battery voltage detection units 313, low voltage alarm units 314, communication interface units 315, low power mode processing units 316 and humidity detection units 317.

[0036] Among them, the touch button detection unit 311 and the LED driving unit 312 are combined one by one, and a universal input and output pin is reused; these universal input and output pins are connected to the anode of the touch button and the LED chip through a resistor, and the cathode of the LED chip is grounded. The touch main control chip 310 switches the input state and output state of these universal input and output pins back and forth to perform time-sharing control. When these universal input and output pins are switched to the input state, it detects whether the touch button 320 is pressed. When it is detected that the touch button is pressed (such as the input voltage meets the threshold and the duration meets the threshold), it switches to the output state and lights up the corresponding LED chip. In this way, half of the pin resources can be saved compared with conventional control.

[0037] Smart door locks usually use a 12-key to 14-key matrix keyboard, including at least 12 keys such as numbers 0-9 and symbols *, #, etc. For this reason, preferably, the number of touch keys 320 is 14, such as Figure 2 As shown. Touch button 320 corresponds to Figure 2 TK1 to TK14 in; LED chip 330 corresponds to Figure 2 D1 to D14 in.

[0038] The two functions of touch button + LED light control and voltage detection + low power alarm can meet the lighting control needs of smart door locks, so that the lock control chip does not need to call software threads to complete the lighting control of the smart door lock, saving the ports and software resources of the lock control chip.

[0039] In the application of smart door locks, four AA batteries are usually used as power sources with a power supply voltage of 6V, or lithium batteries are used as power sources with a power supply voltage of 3.7V. These voltages exceed the operating voltage of the processor of 3.3V, and the battery voltage cannot be directly detected. In this embodiment, the input voltage allowed by the lithium battery voltage detection unit 313 of the touch main control chip 310 is not less than 5V. It can be directly connected to the positive electrode of the lithium battery through the pin VLI and detect the 3.7V lithium battery voltage. It can also be connected to the positive electrode of the battery through a voltage divider circuit to detect the battery voltage after the voltage is reduced. When the lithium battery voltage detection unit 313 detects that the battery voltage is less than the set threshold, it can output a high-level signal or a PWM signal through the output pin LED of the low voltage alarm unit 314 to drive the LED chip and / or a buzzer and other devices to sound and light alarm. The waveform of the output signal of the specific low voltage alarm unit 314 can be defined as needed. This definition does not belong to the focus of the utility model and will not be described in detail here.

[0040] In this embodiment, in order to prevent excessive humidity from affecting the recognition of the touch button, for this reason, in this embodiment, the touch circuit 30 is also provided with a humidity sensor 340, which can be directly installed on the touch circuit board, or led out to the panel of the smart door lock. In this embodiment, the humidity sensor 340 is connected to an analog signal input pin of the touch main control chip 310, and the output voltage signal is given to the touch main control chip 310. A humidity processing unit is defined in the touch main control chip 310, which can judge the ambient humidity according to the voltage collected from the humidity sensor 340, and can adjust the sensitivity of the touch button according to the comparison relationship between the ambient humidity and the touch detection threshold through some conventional algorithms, such as a lookup table. The specific control method of the touch main control chip 310 is not the focus of the utility model, but is only used to illustrate the purpose and technical effect of the temperature sensor, and is not described in detail here.

[0041] The touch main control chip 310 communicates with the lock control circuit through the communication interface unit 315, and sends key input information, low voltage alarm information, sleep wake-up information and other information to the main control chip of the lock control circuit 10, wakes up the lock control circuit 10, and the lock control circuit 10 performs password verification, unlocking and other links. In this embodiment, the communication interface unit 315 is an I2C interface unit, including two signals SDA and SCL. Compared with UART, the I2C interface has the characteristics of convenient control and faster transmission rate, and is more suitable for use in this application. The specific information transmission content is not the focus of the utility model and is not described in detail here.

[0042] The touch control chip 310 is Figure 2 The pin description of U1 in is shown in Table 1:

[0043] Table 1 Touch control chip pin description

[0044] Serial number Pin Name illustrate 1 VDD power supply 2 VLI Lithium battery voltage detection pin 3-16 S1-S14 Touch button detection and LED display pin 17 INT Interrupt input pin 18-19 SDA、SCL I2C Interface 20 RSTN Reset pin, low level is effective 21 led Low voltage warning signal output pin 22 RH Humidity detection pin 23、24 GND Power Ground

[0045] In this embodiment, in addition to input through touch keys, an identity recognition device 20 is also provided to support other forms of identity recognition, such as ID recognition and biometric recognition, etc. For this purpose, the identity recognition device 20 may include functional units such as an ID recognition device and a biometric recognition device. Among them, the ID recognition device is a card reader module, which can read radio frequency identification cards such as low frequency 125KHz, medium frequency 13.56MHz or high frequency 950-960MHz as needed. The biometric recognition device can be an identification device or module that supports fingerprint recognition, face recognition, iris recognition, voiceprint recognition and other biological living characteristics related to humans. The lock control circuit is connected to the ID recognition device and the biometric recognition device, and unlocks according to the unlocking instructions output by the ID recognition device and the biometric recognition device.

[0046] The touch control circuit of the utility model has the following characteristics:

[0047] The touch control circuit adopts the touch detection and LED display multiplexing design, which greatly saves the port resources of the lock control chip.

[0048] The touch control circuit integrates a humidity sensor, which can solve the problem of accidental touch of touch buttons in high humidity environments.

[0049] The touch control circuit has a sleep mode and can be used as a wake-up device for the smart door lock. The lock control circuit and the identity recognition device can be woken up by the touch control circuit, thereby greatly reducing sleep power consumption.

[0050] Although the present invention has been specifically demonstrated and described in conjunction with the preferred embodiments, those skilled in the art should understand that various changes may be made to the present invention in form and detail without departing from the spirit and scope of the present invention as defined in the appended claims, all of which are within the scope of protection of the present invention.

Claims

1. A touch control circuit, characterized in that: It includes a touch main control chip, and a plurality of touch buttons and a plurality of LED chips connected to the touch main control chip; The touch main control chip includes multiple touch button detection units, multiple LED driving units, a lithium battery voltage detection unit, a low voltage alarm unit, a communication interface unit and a low power mode processing unit; The touch button detection unit and the LED driving unit are combined one-to-one, and a universal input and output pin is reused; the universal input and output pin is connected to the touch button and the anode of the LED chip through a resistor, and the cathode of the LED chip is grounded; The lithium battery voltage detection unit is directly or indirectly connected to the positive electrode of the battery to collect the battery voltage; The low voltage alarm unit is used to output a low voltage alarm signal; The low power consumption mode processing unit is used to control the touch main control chip to enter and exit the low power consumption mode; The communication interface unit is used for communication connection with the outside.

2. The touch control circuit according to claim 1, wherein: The operating voltage of the touch main control chip is 3.3V, and the allowable input voltage of the lithium battery voltage detection unit is greater than 5V.

3. The touch control circuit according to claim 1, wherein: The communication interface unit of the touch main control chip is an I2C interface unit.

4. The touch control circuit according to claim 1, wherein: The number of the touch keys is 14.

5. The touch control circuit according to claim 1, wherein: It also includes a humidity sensor connected to the touch main control chip.

6. A smart door lock, characterized in that: It comprises a lock control circuit and a touch control circuit as described in any one of claims 1 to 5, wherein the lock control circuit is communicatively connected with the touch circuit.

7. The smart door lock according to claim 6, characterized in that: The smart door lock is powered by a lithium battery or at least three dry batteries.

8. The smart door lock according to claim 6, characterized in that: It also includes a radio frequency identification card reader connected to the lock control circuit.

9. The smart door lock according to claim 6, characterized in that: It also includes a biometric feature recognition device connected to the lock control circuit.

10. The smart door lock according to claim 9, characterized in that: The biometric recognition device includes at least one of a fingerprint recognition device, a face recognition device, an iris recognition device, and a voiceprint recognition device.

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