MP3388

50V, 8-String White LED Driver

MP3388 Rev. 1.0

www.MonolithicPower.com

1

12/16/2011

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

© 2011 MPS. All Rights Reserved.

The Future of Analog IC Technology

DESCRIPTION

The MP3388 is a step-up converter with

8-channel current sources designed for driving

the white LED arrays for large size LCD panel

backlighting applications.

The MP3388 uses current mode, fixed frequency

architecture. The switching frequency can be

selected at 1.25MHz or 625kHz. It generates an

output voltage up to 50V from a 4.5V to 25V input

supply. The MP3388 independently regulates the

current in each LED string to the user programmed

value set by an external current setting resistor.

The MP3388 applies 8 internal current sources in

each LED string terminal to achieve a current

balance of 3% regulation accuracy between

strings. Its low 600mV regulation voltage on LED

current sources reduces power loss and improves

efficiency.

The MP3388 features external PWM dimming or

DC input PWM dimming, which allows the flexible

control of the backlighting luminance. The dimming

PWM signal can be generated internally, and the

dimming frequency is programmed by an external

setting capacitor.

FEATURES

• High Efficiency and Small Size

• 4.5V to 25V Input Voltage Range

• 50V Maximum Step-up Voltage

• Balanced Driver for 8 Strings of WLED

• 3% Current Matching Accuracy Between

Strings

• Selectable Switching Frequency: 1.25MHz or

625kHz

• PWM or DC Input Burst PWM Dimming

• Programmable Over-voltage Protection

• Under Voltage Lockout

• Open and Short LED protection

• Thermal Shutdown

• Small QFN24 (4x4mm) and 28 pin SOIC

packages

• Halogens Free

APPLICATIONS

• Notebook PC

• Small LCD TV

• Handy Terminals Display

• Automotive System and Tablet Computer

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

4.5V~25V

MP3388

VCC

VIN

COMP VFAULT

SW2

SW1

24

23

22

21

20

19

EN

OSC

FSET

PWMO

GND

PWMI

LED8

LED7

LED6

LED5

LED4

ISET

PGND1

PGND2

OVP

LED1

LED2

LED3

78

9

10

11

12

1

2

3

4

5

6

18

17

16

15

14

13

Enable

PWM

DIMMING

NC

L1

D1

M1

C1

C3

C2

R1

R2

C4

C5

C6