MP1531

Low Power, Triple Output Step-Up

Plus Charge Pump for TFT Bias

MP1531 Rev. 1.2

www.MonolithicPower.com

1

5/22/2006

MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.

© 2006 MPS. All Rights Reserved.

The Future of Analog IC Technology

DESCRIPTION

The MP1531 is a triple output step-up converter

with charge-pumps to make a complete DC/DC

converter to power a TFT LCD panel from a

2.7V to 5.5V supply.

The MP1531 includes a 250KHz fixed frequency

step-up converter and a positive and negative

linear regulator. The linear regulators are

powered via charge-pumps driven by the step-up

converter switch node.

A single on/off control enables all 3 outputs.

The outputs are internally sequenced at

power-on for ease of use. An internal soft-start

prevents overloading the input source at

startup. Cycle-by-cycle current limit reduces

component stress.

The MP1531 is available in both a tiny 16-pin

QFN package (3mm x 3mm) and a 16-pin

TSSOP package.

EVALUATION BOARD REFERENCE

Board Number

Dimensions

EV1531DQ-002A

2.3”X x 2.3”Y x 0.5”Z

FEATURES

• 2.7V to 5.5V Operating Input Range

• 500mA Switch Current Limit

• 3 Outputs in a Single Package

• Step-Up Converter up to 22V

• Positive 10mA Linear Regulator

• Negative 10mA Linear Regulator

• 250mΩ Internal Power MOSFET Switch

• 95% Efficiency

• 1µA Shutdown Mode

• Fixed 250KHz Frequency

• Positive Regulator up to 38V

• Negative Regulator down to -20V

• Internal Power-On Sequencing

• Adjustable Soft-Start/Fault Timer

• Thermal Shutdown

• Cycle-By-Cycle Over Current Protection

• Under Voltage Lockout

• Ready Flag

• 16-Pin TSSOP and QFN (3mm x 3mm) Packages

APPLICATIONS

• TFT LCD Displays

• Portable DVD Players

• Tablet PCs

• Car Navigation Displays

“MPS” and “The Future of Analog IC Technology” are Registered Trademarks of

Monolithic Power Systems, Inc.

TYPICAL APPLICATION

MP1531

SW

FB1

FB3

IN3

GH

CT

IN

PGND

GND

REF

FB2

GL

EN

COMP

IN2

RDY

OFF ON

TO

SW

-4V

2.7V-4.2V

5V

12V

100

90

80

70

60

50

40

30

20

0

100 200 300 400 500 600

LOAD CURRENT (mA)

Efficiency vs

Load Current