MP3388S

50V, 8-String, Step-Up, White LED Driver

MP3388S Rev.1.01

www.MonolithicPower.com

1

10/29/2012

MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.

© 2012 MPS. All Rights Reserved.

The Future of Analog IC Technology

DESCRIPTION

The MP3388S is a step-up converter with 8

current-source channels designed to drive arrays

of

white

LED

for

LCD-panel

backlighting

applications.

The

MP3388S

uses

current-mode,

fixed-frequency architecture, and users can select

a switching frequency of either 625kHz or

1.25MHz. It generates an output voltage up to

50V from a 4.3V-to-25V input supply. The

MP3388S independently regulates the current in

each LED string set by an external current setting

resistor to a user-programmed value.

The MP3388S applies an internal current source

to each LED string terminal, and can achieve a

current balance of 2.5% regulation accuracy

between strings. Its low 600mV regulation voltage

on LED current sources reduces power loss and

improves efficiency.

The MP3388S features external PWM dimming or

DC-input PWM dimming, which allows for flexible

backlight luminance control. The dimming PWM

signal can be generated internally, and the

dimming frequency is programmed by an external

setting capacitor.

FEATURES

 High Efficiency

 Compact Size

 4.3V-to-25V Input Voltage Range

 50V Maximum Step-Up Voltage

 Balanced Driver for 8 WLED Strings

 2.5% Current-Matching Accuracy between

Strings

 Selectable Switching Frequency of 625kHz

or 1.25MHz

 PWM or DC Input-Burst PWM Dimming

 Programmable Over-Voltage Protection

 Under-Voltage Lockout

 Open- and Short-LED Protection

 Thermal Shutdown

 Small QFN24 (4mm × 4mm) Package

APPLICATIONS

 Notebook PCs

 Tablet Computers

 Small LCD TV

 Handheld Terminal Displays

 Automotive Electronics Equipments

All MPS parts are lead-free and adhere to the RoHS directive. For MPS green

status, please visit MPS website under Quality Assurance. “MPS” and “The

Future of Analog IC Technology” are Registered Trademarks of Monolithic

Power Systems, Inc.

TYPICAL APPLICATION

VIN

MP3388S

Enable

NC

C5

C3

VCC VIN COMPVFAULTSW1 SW2

PGND1

PGND2

OVP

LED1

LED2

LED3

LED4

ISET

LED5

LED6

LED7

LED8

PWMI

GND

PWMO

FPWM

OSC

EN

C1

M1

L1

D1

C2

R1

R2

C4

R

SET

V

OUT

C6

DIMMING

4.5V-25V

PWM