LM3445 Datasheet - Triac Dimmable Offline LED Driver
The LM3445 is a specialized integrated circuit that functions as a constant current controller in AC/DC applications, particularly suited for LED lighting systems. Its primary role is to convert a high voltage AC input into a lower voltage DC output while maintaining a constant current to drive LED loads. This adaptability is crucial for applications where dimming is required, especially when interfacing with triac-based dimmers commonly used in residential and commercial lighting.
The architecture of the LM3445 includes features such as adaptive off-time control, which allows the device to adjust its off-time based on load conditions, enhancing efficiency and performance. This characteristic is particularly beneficial in scenarios where the load may vary, ensuring that the output current remains stable despite fluctuations.
In terms of operation, the LM3445 utilizes a buck conversion topology, which is highly efficient for stepping down voltage levels while providing a regulated output current. The device is designed to handle a wide input voltage range, making it versatile for various applications. Additionally, the LM3445 incorporates built-in protections such as over-temperature and over-current protection, which safeguard both the controller and the connected load.
For implementation, the LM3445 requires minimal external components, simplifying the design process. It typically interfaces with a few passive components, such as inductors and capacitors, to form a complete power supply circuit. The output current can be set using an external resistor, allowing designers to fine-tune the current to match the specifications of the LED load.
Overall, the LM3445 stands out as a reliable solution for LED drivers, particularly in environments where dimming is necessary, combining efficiency, safety, and ease of integration into existing lighting systems.The LM3445 (datasheet) is an adaptive constant off-time AC/DC buck (step-down) constant current controller designed to be compatible with triac dimmers 🔗 External reference
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