EV3378-S-00A

4 Strings, Step Up WLED Controller

Plus High Efficiency Step down Converter

EV3378-S-00A Rev.1.0

www.MonolithicPower.com

1

2/2/2015

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© 2015 MPS. All Rights Reserved.

The Future of Analog IC Technology

DESCRIPTION

The MP3378 is a one-chip solution, specially

designed

for

monitor

applications,

which

includes a step-up controller with 4 current

channels for backlight and a high efficiency

buck converter for internal bus voltage or

standby power.

The 4-string WLED controller drives an external

MOSFET to boost up the output voltage from

the input supply. It regulates the current in each

LED string to the programmed value set by an

external current setting resistor. It can support

both analog and PWM dimming independently

to meet the special dimming mode request. In

addition, rich protection modes are also

integrated including OCP, OTP, UVP, OVP,

LED short/open protection, inductor/diode short

protection.

The high efficiency buck converter operates in

the current mode operation with built in

MOSFET and synchronous rectifier. It offers a

very compact solution to achieve excellent load

and line regulation. Full protection features

include OCP and thermal shut down.

The MP3378 is available in SOIC28 package.

ELECTRICAL SPECIFICATIONS

Parameter

Symbol

Value

Units

Input

Voltage

8– 24

V

LEDs #

4 LED strings

10 LEDs/string

LED Current

120/string

mA

(buck)

2

A

FEATURES

WLED Controller:

 4-String,

Max

350mA/String

WLED

Controller

 Up to 24V Input Voltage Range

 2.5% Current Matching Accuracy

 Programmable Switching Frequency

 PWM and Analog Dimming Mode

 LED Open and Short LED Protection

 Programmable Over-Voltage Protection

 Recoverable thermal Shutdown Protection

 Over Current Protection

 Over Temperature Protection

 Inductor/Diode short Protection

Buck Converter:

 90mΩ/40mΩ Low Rds(on) Internal Power

MOSFETs

 Low Quiescent Current

 Fixed 233kHz Switching Frequency

 Frequency Sync from 250kHz to 2MHz

External Clock

 AAM Power Save Mode

 Internal Soft Start

 OCP Protection and Hiccup

 Over Temperature Protection

 Output Adjustable from 0.8V

APPLICATIONS

 LCD Monitors

All MPS parts are lead-free, halogen 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.