The iW3617 is a high performance two-stage AC/DC power supply controller optimized for dimmable LED luminaires at 25W of output power. Compliant to the IEC61000-3-2 standard for electromagnetic compatibility (EMC), the iW3617 incorporates a two-stage driver to achieve Power Factor (PF) greater than 0.95 from an input voltage of either 120V_AC or 230V_AC. Incorporating iWatt's proprietary Flickerless™ technology, the iW3617 automatically detects the dimmer type and phase, permitting the industry's broadest compatibility with analog and digital dimmers. This intelligent dimmer interface also removes the need for the high-power bleeder resistor normally required to load a Triac dimmer, reducing solution size and cost. iWatt’s Flickerless technology also removes virtually all visible and invisible LED flicker to provide a stable light output under all conditions. The iW3617 is compaptible with solid-state lighting industry standard Zhaga for hot-plug LED modules and also incorporates mapping options for the dimming function that fall within the NEMA SSL6 dimming curves for incandescent replacement bulbs. The iW3617 is feature rich to ease design and provide a very robust solution, integrating iWatt’s EZ-EMI^® technology and several protection features.  The protection features include the ability to run off of an emergency backup DC voltage rail in the event of a power outage and an NTC-based temperature protection circuit that reduces the output drive to the LEDs in order to protect the circuit from overheating while maintaining light output.  Additional protection circuits include over voltage, over current and open LED detection circuits.  The iW3617 also incorporates iWatt's proprietary PrimAccurate™ primary-side control technology, minimizing the external component count by removing the need for the traditional opto-coupler and external compensation components, reducing solution size and cost.

The iW3617 is available in two versions, the iW3617-00 which is optimized for 120V_AC input applications and the iW3617-01, which is optimized for 230V_AC applications. 

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