MP3388S Datasheet, PDF (1/15 Pages) Monolithic Power Systems – 50V, 8-String, Step-Up, White LED Driver

The Future of Analog IC Technology
MP3388S
50V, 8-String, Step-Up, White LED Driver
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
M1
L1
D1
V_OUT
4.5V-25V ^C1
C2
R1
R2
C3
C4
Enable
NC
VCC VIN COMPVFAULTSW1 SW2
EN
PGND1
OSC
PGND2
C5
PWM
DIMMING
FPWM _MP3388S OVP
PWMO
C6
GND
LED1
LED2
PWMI
LED3
LED8 LED7 LED6 LED5 ISET LED4
R_SET
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.