LD7577

1/15/2009

1

Leadtrend Technology Corporation

www.leadtrend.com.tw

LD7577-DS-01 January 2009

High Voltage Green-Mode PWM Controller with

Brown-Out Protection

Rev. 01

General Description

The LD7577 integrates several functions of protections, and

EMI-improved solution in SOP-8 package. It minimizes the

component counts and the circuit space.

The device provides functions of low startup current,

green-mode power-saving operation, leading-edge blanking

of the current sensing and internal slope compensation.

Also, it features more protections like OLP (Over Load

Protection), OVP (Over Voltage Protection), and brownout

protection to prevent the circuit from being damaged under

abnormal conditions.

Features

High-Voltage (500V) Startup Circuit

Current Mode Control

Non-Audible-Noise Green Mode Control

UVLO (Under Voltage Lockout)

LEB (Leading-Edge Blanking) on CS Pin

Internal Slope Compensation

OVP (Over Voltage Protection) on Vcc Pin

AC Input OVP (Over Voltage Protection)

OLP (Over Load Protection)

Precision Brownout Protection

500mA Driving Capability

Applications

Switching AC/DC Adaptor and Battery Charger

Open Frame Switching Power Supply

LCD Monitor/TV Power

Typical Application

EMI

Filter

photocoupler

AC

input

TL431

*

*

*See Application Information

LD7577

VCC

HV

BNO

GND

COMP

CS

OUT