LD5857

4/15/2014

1

Leadtrend Technology Corporation

www.leadtrend.com.tw

LD5857-DS-00 April 2014

Boost Controller for LED Backlight

REV: 00

General Description

The LD5857 is a wide-input asynchronous current mode

boost controller, capable to operate in the range between

9V and 28V and to generate 12V of voltage to the GATE

pin of MOSFET to reduce thermal loss. The current mode

control architecture enhances transient response and

simplifies the loop compensation. The DIM input enables

the brightness control for LED Backlight or LED lighting.

The device also features internal slope compensation,

input voltage under-voltage lockout, output voltage short

circuit protection, cycle-by-cycle current limit and thermal

shutdown protection.

Features

Dimming Output with Software Control

Applications

Typical Application

VCC

DRV

CS

DIM

OVP

FB

COMP GND

LD5857

5

1

4

6

3

8

2

VCC

7

Application circuit