LM3445 TRIAC Dimmable LED Driver


LED driver from National Semi delivers a wide, uniform dimming range free from flicker

National Semiconductor's TRIAC dimmable offline LED driver solution is perfect for any application where an LED driver must interface to a standard TRIAC wall dimmer. National's TRIAC dimmable LED driver delivers a wide and uniform dimming range that is free of flicker with best-in-class dimming performance, and high efficiency—all while maintaining ENERGY STAR® power factor requirements in a typical application. Conventional TRIAC dimmers are designed to interface to a resistive load (halogen or incandescent bulbs). Since the LEDs do not appear to be a resistive load, dimming LEDs from a standard TRIAC wall dimmer is a challenge. The LM3445 LED driver enables a direct replacement of incandescent lamp systems that are currently interfaced to a TRIAC dimmer without having to change the original infrastructure or sacrifice performance.      LM3445 Datasheet National Semiconductor LM3445 TRIAC Dimmable LED Driver
  • Overview
  • Features & Applications
  • Diagram
  • Buy Now


Overview

Full range dimming capability offers 100:1 full range dimming capability, going from full light to nearly imperceptible light in a continuous range without being extinguished and maintaining a constant current to large strings of LEDs driven in series off a standard line voltage.

Easy of use enables a direct replacement of incandescent or halogen lamp systems that are currently interfaced to a TRIAC dimmer without having to change the original infrastructure or sacrifice performance. In addition, National’s online design tools allow for easy and quick design-in.

Uniform dimming allows master-slave operation control in multichip solutions, enabling a single TRIAC dimmer to control multiple strings of LEDs with smooth, consistent dimming free of flicker.


Features
  • TRIAC dim decoder circuit for LED dimming
  • Application voltage range 80VAC to 277VAC
  • Capable of controlling LED currents greater than 1A
  • Adjustable switching frequency
  • Low quiescent current
  • Adaptive programmable off-time allows for
    constant ripple current
  • Thermal shutdown
  • No 120Hz flicker
  • Low profile, 10-pin MSOP or 14-pin SOIC packages
  • Patent pending drive architecture

Applications
  • Retrofit TRIAC dimming
  • Solid state lighting
  • Industrial and commercial lighting
  • Residential lighting

  • RoHS Compliant


Diagram

National Semiconductor LM3445 TRIAC Dimmable LED Driver Diagram



Buy Now

National Semi
Part Number
Digi-Key
Part Number
Packaging
Current -
Output/Channel
Voltage - Supply
Package /
Case
LM3445MM/NOPB
Tape & Reel
1A
8V ~ 12V
10-MSOP, Micro10™,
10-uMAX, 10-uSOP
Cut Tape
LM3445M/NOPB
Tube
1A
8V ~ 12V
14-SOIC

Eval Boards
Digi-Key
Part Number
Current -
Output/Channel
Features
Voltage -
Input
350mA
Dimmable
90VAC ~ 135VAC
500mA
Dimmable with Standard TRIAC Dimmer,
Power Factor Correction
176VAC ~ 305VAC
205mA~340mA
Dimmable
85VAC ~ 135VAC
350mA
Dimmable, TRIAC Dimmable
185VAC ~ 265VAC
365mA
Dimmable, TRIAC Dimmable
90VAC ~ 135VAC


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