TI（NS） LM3448 TRIAC調光離線LED驅動解決方案

關鍵詞： LED驅動 , LM3448 , TI , Triac

TI（NS）公司的LM3448 是集成了600V的MOSFET的TRIAC相位調光的離線LED驅動器，應用電壓范圍從85VAC到265VAC，可調整的開關頻率，不會出現(xiàn)120Hz的閃爍，能為大功率LED提供恒流，主要用于改進型TRIAC調光，固態(tài)照明，工業(yè)和商業(yè)照明以及住宅照明。本文介紹了LM3448主要特性，簡化方框圖，基本的TRIAC調光電路，典型LED驅動器應用電路以及多種設計案例和指標及其所用材料清單，LM3448 A19 Edison改進型評估板電路圖和材料清單。

LM3448：Phase Dimmable Offline LED Driver with Integrated FET

The LM3448 is an adaptive constant off-time AC/DC buck (step-down) constant current LED regulator designed to be compatible with TRIAC dimmers. The LM3448 provides a constant current for illuminating high power LEDs and includes a phase angle dim decoder. The dim decoder allows wide range LED dimming using standard forward and reverse phase TRIAC dimmers. The integrated high-voltage and low Rdson MOSFET reduces design complexity while improving LED drive`rm factor LED drivers suitable for integrated LED lamps with very low external component count. The LM3448 also provides the flexibility required to implement both isolated and non-isolated solutions based on the Flyback, Buck or Buck-Boost topology using either active or passive power factor correction (Valley- Fill) circuits. Additional features include thermal shutdown, current limit and VCC under-voltage lockout.

LM3448主要特性：

■ Input phase angle dim decoder circuit for LED dimming

■ Integrated, vertical 600V MOSFET with superior avalanche energy capability

■ Application voltage range 85VAC – 265VAC

■ Adjustable switching frequency

■ Adaptive programmable off-time allows for constant ripple current

■ No 120Hz flicker possible

■ Low quiescent current

■ Thermal shutdown

■ Low profile 16-pin Narrow SOIC package

■ Wave solder capable

LM3448應用：

■ Retrofit TRIAC Dimming

■ Solid State Lighting

■ Industrial and Commercial Lighting

■ Residential Lighting