This part is a kind of semiconductor called LM3445.

Function of this product has Triac Dimmable Offline LED Driver.

Manufacturers : National Semiconductor

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LM3445 Triac Dimmable Offline LED Driver February 10, 2009 LM3445 Triac Dimmable Offline LED Driver General Description The LM3445 is an adaptive constant off-time AC/DC buck (step-down) constant current controller designed to be compatible with triac dimmers. The LM3445 provides a constant current for illuminating high power LEDs and includes a triac dim decoder. The dim decoder allows wide range LED dimming using standard triac dimmers. The high frequency capable architecture allows the use of small external passive components. The LM3445 includes a bleeder circuit to ensure proper triac operation by allowing current flow while the line voltage is low to enable proper firing of the triac. A passive PFC circuit ensures good power factor by drawing current directly f [ ... ]

LM3445 PDF Datasheet Download