A conventional smart door lock may include a wireless communication module, power management, lock body, panel, battery, smart door lock control board, display, motor, sensor, electromagnetic clutch, control system, etc.
The part of smart door lock products that usually uses discrete device products is the smart door lock control board, which is the brain system of the door lock and is responsible for processing and transmitting data. The smart control board is usually composed of MCU, memory, clock, keyboard, LCD display, demodulator, line multiplexing and monitoring, A/D conversion, buzzer and other electronic components. Among them, the circuits that may use discrete devices mainly include power management circuit, power detection circuit, anti-reverse circuit, small signal control circuit, buzzer circuit, LED drive circuit, etc.
The working state of the smart door lock is as follows: the monitor is always in the receiving state, receiving the alarm information and status information sent by the electronic lock in a fixed format. The electronic lock is based on the MCU and equipped with corresponding hardware circuits to complete the setting, storage, identification and display of passwords, drive the electromagnetic actuator and detect its driving current value, receive the alarm signal sent by the sensor, send data, etc. The single-chip microcomputer receives the keyed code and compares it with the password in the EEPROM. If the password is correct, the electromagnetic actuator is driven to unlock. Otherwise, if it exceeds three times, the MCU will alarm the smart monitor.
For example, in the power management circuit, a stable voltage and current are provided for the door lock to realize the switch control and protection functions, save energy and extend battery life, etc.
The power detection circuit mainly monitors the power supply voltage of the door lock, provides overvoltage/undervoltage protection, power failure detection, and power status indication, etc. It detects the battery voltage to determine the battery power status and promptly reminds the user to charge or replace the door lock battery.
The circuit often has the power supply connected in reverse and burns the circuit board. At this time, the door lock anti-reverse circuit is very important. The anti-reverse circuit function of the smart door lock is mainly to prevent the power supply from being connected in reverse and protect the safety of equipment and personnel. It uses the difference in polarity or direction of the circuit to determine whether the connection is correct. When the circuit connection does not match the preset direction or polarity, the anti-reverse circuit will immediately cut off the power or signal.
The main function of the small signal control circuit is to control and adjust the various functions of the door lock to ensure the normal operation and safety performance of the door lock. Through the small signal control circuit, the door lock switch can be controlled to ensure that the door lock can be opened and closed normally. It usually has a feedback function and can feed back the status information of the door lock to the control system through the small signal control circuit, such as whether the door lock has been successfully opened or closed.
The buzzer circuit is an electronic sounder with an integrated structure, powered by a DC voltage, and its working principle is based on a vibration device and a resonance device. The buzzer circuit usually consists of a control circuit and a buzzer. The control circuit can be a simple switch or an analog or digital circuit that controls the frequency and volume of the buzzer. The buzzer circuit is usually combined with a small signal circuit to achieve the sound control effect.
Smart door locks are usually equipped with LED indicators to display the status of the lock, such as unlocking status, locking status, low battery warning, etc. These LED lights can control the on and off and brightness, so that they can be displayed flexibly according to needs. In addition, module circuits such as motor drive systems and Internet of Things communication systems may also use discrete devices, depending on the specific technical solution design chosen by the customer.
In short, smart door locks will be used more and more, and the product performance will be more powerful. The products are developing in the direction of miniaturization, low power consumption, high frequency, higher integration, long life and intelligence. When designing products, customers can comprehensively select appropriate solutions and choose the most suitable components to ensure product quality and market competitiveness.