As more and more homeowners want to transform smart locks (or electronic locks) into their buildings, wireless battery-powered smart locks are gaining popularity in today's market. In smart lock applications, large Current motors and radios typically deplete batteries quickly, causing battery life to be affected. Replacing multiple batteries may be a timely and expensive problem, so reducing average current consumption is a key design consideration.
The intelligent door lock solution of TI's products from Dainichi World Pacific Proxy consists of an ultra-low power wireless MCU, a DRV8833 motor driver and a 9-channel LED driver LP55231, and an ultra-low IQ buck converter TPS62745. The program is enabled by TI. Light-load-efficient DC/DC converter, SimpleLinkTM ultra-low-power wireless MCU platform with integrated motor driver and RGB LED driver. With a light-load, high-efficiency power supply topology, low standby current and long shutdown state To extend battery life. This solution provides system designers with a low-power smart door lock design that can be used for electronic locks, door keypads, readers, wireless automatic shutters and HVAC dampers, actuators, etc. It selects the battery Power supply, the main consideration is the capacity and popularity of the battery platform, and AA batteries have greater capacity than AAA batteries.
Product Features:
• 4 AA batteries in series, with battery life of 5 years or more; • Locking or unlocking activity 24 times a day; • BLE radio connection cycle; • Motor driver with integrated FET and current sense comparator, with minimal separation Components enable easy design and smaller solution sizes; • Voltage-based battery fuel gauges, integrated DC/DC converters; • Adopt third-party BLE iOS and Android applications through BLE testing; • Up to 4 seconds of availability Configure advertising interval.
Product description:
Power Technology: The intelligent door lock solution of TI's products from Dainichi World Wide Agent has three main power topologies: Low-dropout (LDO) regulators, buck converters (also called bucks), and boost (see The following figure) LDO and buck-boost voltage generated low-voltage power rail to run MCU, higher voltage components run at higher battery voltage. Enhancements are event-related because each lock and unlock event must be increased Voltages from 3V to 5V are used for motor and LED operation. The buck configuration is chosen because the LDO has ground leakage current and the buck has zero ground leakage current, so it is more efficient. The TPS62745 buck converter is chosen because it is Low power consumption provides additional benefits in design. The TPS device has a select line that allows the user to select the output voltage, so no feedback resistor is required. Because of this, the cost of the bill of materials can slightly reduce the feedback resistance. The TPS62745 can dynamically enable or disable the battery voltage Check using an enable pin and an external resistor divider. Because of the voltage, the energy is conserved. The divider can only be used when battery voltage check is required. The rest of the time is allocated. Circuit does not use energy, there is no connection. TPS62745 at very light load is also effective, when it is 10μA efficiency of 85%.
MCUs with Integrated Bluetooth® Low-Power Radio: Using TI's SimpleLink ultra-low-power wireless MCU platform, the combination of low-power radios and MCUs extends the battery life of the sensor's end node. Moreover, the CC2650 device is a multi-standard device. For Bluetooth, ZigBee®, 6LoWPAN and ZigBeeRF4CE remote control applications. In this TI design, Bluetooth is an optional protocol, but the hardware can also work with other protocols.
Motor Drivers: Drive Current, Supply Voltage Range, Load Motor Type and Safe Shutdown are all factors when choosing a motor driver. The DRV8833 can drive many types of motors and inductive loads with a peak current of 2A and a supply voltage range of 2.7V to 10.8V, Ideal for use with four AA batteries. Nominal driving voltage The battery voltage is 5V.
User Interface: The user interface on the circuit board must be simple, low power, accurate enough to show all the necessary information to know what the device is doing. Six RGB LEDs are chosen in a circular arrangement to allow different patterns and colors to be presented to the user Communicate what is happening. The LP55231 is a 9-channel LED driver, where two channels can implement the implementation of the 6 RGB LEDs previously discussed. It also includes an efficient LED driver and a charge pump (up to 94%) with 200nA standby current , Automatic power saving mode, programmable LED mode, and small package size (4mm x 4mm) Since this reference design implements two LED drivers, the LP55231 was chosen because it allows simple synchronous trigger inputs.
Product Features:
CC2640: 2.4GHz low-power Bluetooth ARM® Cortex®-M3 processor with ultra-low power wireless MCU (32-bit).
DRV8833: Dual H-Bridge Motor Driver with Motor Current Control and Low RDSon 360 mΩ.
LP55231: Nine channel LED driver designed to provide lighting effect equipment for mobile devices.
TPS62745: Ultra-low IQ buck converter with 16 selectable output voltages (1.8V to 5.5V) 3.3V with load current ≥15μA and efficiency of 90%.
Applications: • Door keypads and readers; • Electronic smart locks; • HVAC valve and brake controls; • Smoke and temperature detectors; • Electric shutters.