LM3447 Datasheet PDF – PFC Flyback Controller

Part Number: LM3447

Function: Regulated PFC Flyback Controller for LED Lighting

Package: TSSOP 14-pin

Manufacturer: Texas Instruments


LM3447 Pinout



The LM3447 is a versatile power factor correction (PFC) controller designed to meet the performance
requirements of residential and commercial phase-cut dimmer compatible LED lamp drivers.

The device incorporates a phase decoder circuit and an adjustable hold current circuit to provide smooth, flicker free dimming operation. A proprietary primary side control technique based on input voltage feedforward is used to regulate the input power drawn by the LED driver and to achieve line
regulation over a wide range of input voltage.

Valley switching operation is implemented to minimize switching loss and reduce EMI. An internal thermal foldback circuit is provided to protects the LEDs from damage based on the temperature sensed by a single external NTC resistor. Additional features include LED open circuit and short circuit protection, cycle-by-cycle FET over-current protection, burst mode fault operation using an internal 812ms fault timer and internal thermal shutdown.

Official Site : https://www.ti.com/product/lm3447

LM3447 Datasheet


1. Power Factor Correction with Low Total Harmonic Distortion

2. Primary Side Control Using Input Voltage Feedforward Technique

3. Input Power Regulation Scheme with Improved Line Regulation

4. Constant Power Operation of LEDs to Compensate for Forward Voltage
Variations Over Temperature and Lifetime

5. Fixed Frequency Discontinuous Conduction Mode Operation



1. Recessed LED Downlights and Pendant Lights

2. Industrial and Commercial Solid State Lighting

LM3447 Datasheet PDF Download

LM3447 pdf

Other data sheets are available within the file: LM3447MT, LM3447MTE, LM3447MTX