LEDs are typically used as indicator lamps in various devices and lighting applications. Modern LED devices are available with very high brightness across the visible, ultraviolet and infrared wavelengths.
LED lighting power management typically consists of power conversion, constant current regulation and fault handling. Key design considerations include high integration, small form factor(s), support for a variety of standard lighting, versatile communication protocols, energy efficiency and high temperature operation capabilities.
Atmel’s ATXMEGA E AVR MCU can be used by engineers to design an advanced LED power management system that follows the above-mentioned requirements. Indeed, the XMEGA E is highly integrated to support multiple LED driver topologies – while leaving CPU resources for additional application functionalities.
Additional key ATXMEGA E AVR MCU capabilities for LED lighting power management include dual high-speed 40ns Analog Comparators for current regulation, multiple high speed 128MHz timers that facilitate fast PWM, dual digital to analog converters for peak current management, asynchronous event system for ultra-fast response and control loops, a custom logic (XCL) block that eliminates the need for external logic components and an energy efficient design.
“Plus, the XMEGA E, with its rich analog peripheral features, can run complicated power control algorithm (e.g. PFC) to achieve high power efficiency,” an Atmel engineering rep told Bits & Pieces. “The XMEGA E also offers ultra low power consumption as low as 100uA/MHz in active mode and 100nA in RTC/RAM retention. Last, but certainly not least, the XMEGA E is qualified to operate at high temperatures (105C-125C).”
In terms of lighting communication protocols, Atmel offers hardware DALI support via XCL block in XMEGA E, as well as software support for DMX, LWmesh, interface to PLC, ZigBee Light Link, ZigBee Home Automation along with a variety of wireless protocols.