LM3445-120VFLBK: 365mA @ 27V Max, 120V, TRIAC

Summary

This demonstration board highlights the performance of a LM3445 based Flyback LED driver solution that can be used to power a single LED string consisting of 4 to 8 series connected LEDs from an 90 VRMS to 135 VRMS, 60 Hz input power supply. The key performance characteristics under typical operating conditions are summarized in this application note.

This is a two-layer board using the bottom and top layer for component placement. The demonstration board can be modified to adjust the LED forward current, the number of series connected LEDs that are driven and the switching frequency. Refer to the LM3445 datasheet for detailed instructions.

A bill of materials is included that describes the parts used on this demonstration board. A schematic and layout have also been included along with measured performance characteristics.

Key Features:

Drop-in compatibility with TRIAC dimmers
Line injection circuitry enables PFC values greater than 0.95
Adjustable LED current and switching frequency
Flicker free operation

Specifications

Manufacturer	Texas Instruments
Category	Lighting
Sub-Category	LED Drivers - AC / Offline
Eval Board Part Number	296-49205-ND
Eval Board Supplier	Texas Instruments
Eval Board	Board not Stocked
AC Voltage	115 V
Outputs and Type	1 Isolated
Current Out	365 mA
Voltage Out (Max)	27 V
Efficiency @ Conditions	>79%, 120V in, 6 LEDs @ 365 mA (No TRIAC)
Features	Current Limit (Adj. or Fixed) Dimming Control PFC Thermal Protection Under Voltage Protection, Brown-Out
Switching Frequency	79 kHz
Component Count + Extras	50 + 15
Design Author	Texas Instruments
Application / Target Market	Lighting: LED Home Lighting
Voltage In	90 ~ 135 VAC
Power Factor
Standard(s)
Main I.C. Base Part	LM3445
Date Created By Author	2010-08
Date Added To Library	2012-07