Smart door lock solution

Summary:

Smart door locks, a prime example of seamlessly integrating traditional mechanical locks with modern technology, are redefining the boundaries between home security and convenient living through groundbreaking innovation. Supported by cutting-edge technologies like biometrics, IoT, and electronic information systems, these smart locks have abandoned the traditional key-based unlocking model. They usher in a new era of diversified and intelligent access control, significantly enhancing both home security performance and user experience. These innovations now hold a pivotal position in modern lifestyles.

1、Existing technical pain points and industry challenges of intelligent door locks

 

While smart door locks have achieved widespread adoption, they still face multiple technical challenges. In biometric systems: fingerprint recognition is affected by moisture and wear, while facial recognition shows high error rates under complex lighting conditions. Insufficient data encryption in locks poses risks of cloud data leakage. Power management issues: Communication modules (Wi-Fi, Bluetooth) consume excessive power, resulting in short battery life. Voltage fluctuations may cause system crashes or performance degradation. Environmental adaptability: Electronic components degrade in extreme temperatures (high/low). Poor coordination between mechanical structures and electronic modules leads to frequent malfunctions. System compatibility and data synchronization: Non-interoperable protocols across brands hinder unified management. Power outages often cause time loss in systems, compromising log accuracy.

2、Corebai dual chip technology solution: build a solid foundation of stability and precision

CBM1117 and CBM1307 products launched by Corebai provide key support for smart door locks from the dimensions of power management, time and data management, and jointly build efficient and stable solutions:

RTC (Real-Time Clock)

The CBM1307 real-time clock chip delivers low error rates, providing precise time benchmarks for door locking functions and event logging. Its 56-byte non-volatile memory securely stores encrypted keys and other data, with write protection preventing tampering. An automatic master-slave power switching mechanism ensures uninterrupted time recording and data storage during power outages.

LDO (low differential linear regulator)

As an efficient low-dropout (LDO) chip, CBM1117 delivers a stable 0.8A current output with a wide voltage input range of 2.6V to 15V, providing pure and reliable power supply for critical components like fingerprint recognition and communication modules. Its thermal overload protection and current-limiting features prevent equipment damage from abnormal currents, ensuring secure and dependable power supply for door locks.

The following is the application block diagram of smart door lock:

 

**RTC recommends CBM1307;

**LDO recommends CBM1117;

Corebai has launched the following products for this intelligent door lock scheme:

 

CBM1307 is a real-time clock chip with the following characteristic parameters:

 

l Timed accurately

The system utilizes an external 32.768kHz crystal oscillator as the reference clock source, delivering exceptional timing accuracy. This provides a reliable time base for smart door lock functions like automatic locking and unlocking, ensuring precise execution at preset intervals. Additionally, its high-precision timestamping feature meticulously records each lock operation, generating detailed logs that help users promptly detect abnormal activities and enhance home security.

l  Low-power design

The power supply current is less than 500nA, which can significantly reduce the overall power consumption and prolong the battery life under the long standby scenario of smart door locks, which is particularly important for smart door locks using battery power.

l Data storage and protection

56 bytes non-volatile RAM: can be used to store key data of smart door lock, such as encryption key, temporary password, etc. Even if the power is lost, the data will not be lost, ensuring data security.

Write protection function: to prevent accidental changes of data, the internal circuit design can also prevent reverse charging current, further improving the reliability of data storage.

l Power management is excellent

The integrated power control circuit can accurately detect the power supply voltage and automatically complete the switching between main power supply and backup power supply. When the main power supply is interrupted, it can quickly and automatically switch to the backup battery power supply to ensure that the timing function and data storage are not affected, and the accurate time recording can be maintained for more than 10 years.

l Strong interface compatibility

Supports standard and fast mode I2C interface (standard 100KHz, high speed 400KHz), which can be easily connected with other I2C devices, convenient to access the overall circuit system of intelligent door lock, and adapt to different hardware architectures.

l The time and date functions are rich

It not only provides detailed time and date information such as seconds, minutes, hours, days, months, and years, but also automatically adjusts the number of days in a month, including accurate correction for leap years. It supports 24-hour and 12-hour time display, and can set different date formats to meet the usage habits of different regions and users.

l Wide temperature range

The working temperature range is-40℃ to + 85℃, no matter in cold or high temperature environment, it can operate stably, ensuring that the time management function of the smart door lock is not affected by environmental temperature changes.

 

CBM1117 is a low differential linear regulator LDO with the following characteristic parameters:

 

l Low voltage difference characteristics: Low voltage difference voltage. When output the rated current, compared with traditional voltage stabilizer, it can stabilize the output under the condition of small difference between input voltage and output voltage, effectively reduce power consumption, improve power supply efficiency, and prolong the endurance time of battery-powered equipment.

l High precision output: The output voltage has high accuracy, and the typical value can reach ±1%. It can provide stable and reliable power supply for circuit modules with high requirements on voltage stability, ensure smooth operation of equipment, and effectively avoid performance degradation or failure caused by voltage fluctuation.

l Low static current: The static current is small, even in light load or standby state, it only consumes a very little current, further reducing the power consumption of the system, especially suitable for power sensitive portable equipment or battery powered equipment.

l Fast transient response: can quickly respond to the change of load current, quickly adjust the output voltage when the load changes, maintain the stability of voltage, ensure the stability of power supply, and adapt to the dynamic load demand.

3、Scenario implementation scenario and actual performance

Smart door locks, with the advantages of convenience, security and intelligence, are empowered by Corebai's technology. Especially in the field of smart door locks, through research and innovation, they have been widely used in a variety of scenarios, reshaping the access management mode of different Spaces, such as home, office or hotel, to meet the needs and preferences of different users.

(1) Home Security: A standard feature in modern households, this system addresses common issues like forgotten keys or lost locks. Family members can access homes freely using fingerprints, passwords, or mobile apps. Households with elderly members and children no longer need to worry about key management. Temporary visitors can also enter conveniently through temporary passwords, significantly enhancing both home security and convenience.

(2) Apartments and Long-Term Rental Housing: Apartment operators and long-term rental platforms utilize smart door locks for remote management. Tenants can obtain unlocking permissions via mobile devices without requiring physical key exchanges upon check-in, with access rights automatically revoked after lease termination to reduce administrative costs and key disputes. The system also enables real-time monitoring of lock status, allowing prompt handling of abnormal conditions.

(3) Hotels & Homestays: Deliver self-service check-in experiences eliminating front desk queues. Guests access door access via mobile apps, enhancing both efficiency and guest satisfaction. Hotel managers can flexibly configure access validity periods through backend systems for streamlined room management. Meanwhile, in-depth analysis of lock usage data enables continuous optimization of service processes.

(4) Office Facilities: The enterprise's office areas utilize smart door locks that implement hierarchical access controls based on employee departments and positions. Restricted zones are exclusively accessible to authorized personnel, ensuring both operational security and privacy protection. Furthermore, the system integrates time clock functionality with key unlocking mechanisms, streamlining attendance procedures and enhancing management efficiency.

(5) Campus Dormitories: This system effectively addresses common issues like key loss and misuse among students, thereby enhancing overall dormitory security. The school implements centralized management authority, eliminating the need to replace locks when new students enroll or graduates leave campus, ensuring efficient operations. Additionally, through real-time access tracking via smart lock systems, the institution can monitor student movements in real time, further safeguarding campus safety.

(6) Commercial shops: The shopkeeper can keep track of the opening status of the shop at any time through the mobile phone, and assign different opening permissions to employees at different times. In case of emergency, the shopkeeper can remotely check the lock status and take measures, such as reporting to the police in time if abnormal unlocking attempts are found, so as to ensure the safety of the shop property.