Fairchild FEBFL77944_L80L012A, Руководство пользователя

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© 2016 Fairchild Semiconductor Corporation 3 FEBFL77944_L80L012A_B
• Rev. 1.0
This user guide supports the evaluation kit for the FL77944. It should be used in
conjunction with the FL77944 datasheet as well as Fairchild’s application notes and
technical support team. Please visit Fairchild’s website at
www.fairchildsemi.com .
1. Introduction
This document describes a direct AC line LED driver with a minimal number of external
components. The input voltage range of the LED driver board are classed as low-line
application for 98 V
AC
~ 142 V
AC,
with a single DC output, constant current depends on
the Rcs value. This document contains a general description of the FL77944, the normal
configuration specification, schematic, bill of materials, and typical operating
characteristics.
1.1. General Description of FL77944MX
The FL77944 is a direct AC line LED driver with a minimal number of external RC
passive components. In normal configuration, one resistor is to adjust LED power, and
one capacitor is to provide a stable voltage to an internal biasing shunt regulator.
The FL77944 provides phase-cut dimming with wide dimming range, smooth dimming
control and good dimmer compatibility. It achieves the high efficiency with high PF and
low THD which makes the FL77944 suitable for high-efficiency LED lighting systems.
The FL77944 has a dedicated DIM pin which can be used with analog or digital PWM
dimming. The FL77944 can also be used with a rheostat dimmer switch which is suitable
for desktop or indoor lamps.
High wattage design of the FL77904 can be implemented with multiple IC embedded in
parallel for street lighting and down lighting applications.
1.2. Controller Features

The simplest Direct AC LED Driver with Only Two External RC Passive
Component

Wide AC Input Range : 90~305 V
AC

Four Integrated High-Voltage LED Constant Current Sinks of up to 150 mA
(RMS) Capability

TRIAC Dimmable (Leading/Trailing Edge)

Rheostat Dimmable

Analog/Digital PWM Dimming Function

High Power Factor (above 0.98 in normal configuration)

Adjustable LED Power with an External Current Sense Resistor

Low Harmonic Content (THD under 20% in normal configuration)

SOP16 EP Package

Flexible LED Forward Voltage Configuration

Power Scalability with Multiple Driver ICs

Over-Temperature Protection (OTP)