© 2012 Fairchild Semiconductor Corporation

3

FEBFL7701_L30U003A • Rev. 1.0.2

This user guide supports the Evaluation kit for the FL7701. It should be used in

conjunction with the FL7701 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 the proposed solution for a universal-input 2.4W LED ballast

description of FL7701, the power supply specification, schematic, bill of materials, and

the typical operating characteristics.

1.1. General Description

The FL7701 LED lamp driver is a simple IC with PFC function. The special “adopted

digital” technique automatically detects input voltage condition and sends an internal

reference signal, resulting in high power factor. When an AC input voltage is applied to

the IC, the PFC function is automatically enabled. Otherwise, when a DC input is applied

to the IC, the PFC function is automatically disabled. The FL7701 does not require a bulk

capacitor (electrolytic capacitor) for supply rail stability, which can significantly affect

LED reliability.

1.2. Key Features