General Description

The MAX8758 includes a high-performance step-up regu-

lator, a high-speed operational amplifier, and a logic-

controlled, high-voltage switch-control block with pro-

grammable delay. The device is optimized for thin-film

transistor (TFT) liquid-crystal display (LCD) applications.

The step-up DC-DC regulator provides the regulated sup-

ply voltage for the panel source driver ICs. The converter

is a high-frequency (640kHz/1.2MHz), current-mode regu-

lator with an integrated 14V n-channel power MOSFET.

The high-switching frequency allows the use of ultra-small

inductors and ceramic capacitors. The current-mode con-

trol architecture provides fast transient response to pulsed

loads. The regulator achieves efficiencies over 85% by

bootstrapping the supply rail of the internal gate driver

from the step-up regulator output. The step-up regulator

features undervoltage lockout (UVLO), soft-start, and

internal current limit. The high-current operational amplifier

is designed to drive the LCD backplane (VCOM). The

amplifier features high output current (±150mA), fast slew

rate (7.5V/µs), wide bandwidth (12MHz), and rail-to-rail

inputs and outputs.

The MAX8758 is available in a 24-pin, 4mm x 4mm, thin

QFN package with a maximum thickness of 0.8mm for

ultra-thin LCD panels. The device operates over the

-40°C to +85°C temperature range.

Applications

Notebook Displays

LCD Monitors

Features

♦ 1.8V to 5.5V Input Voltage Range

♦ Input Undervoltage Lockout

♦ 0.5mA Quiescent Current

♦ 640kHz/1.2MHz Current-Mode Step-Up Regulator

Fast Transient Response

High-Accuracy Output Voltage (1.5%)

Built-In 14V, 2.5A, 115m

Ω MOSFET

High Efficiency

Programmable Soft-Start

Current Limit with Lossless Sensing

Timer-Delay Fault Latch

♦ High-Speed Operational Amplifier

±150mA Output Current

7.5V/µs Slew Rate

12MHz, -3dB Bandwidth

Rail-to-Rail Inputs/Outputs

♦ Dual-Mode™, Logic-Controlled, High-Voltage

Switch with Programmable Delay

♦ Thermal-Overload Protection

♦ 24-Pin, 4mm x 4mm, Thin QFN Package

Step-Up Regulator with Switch Control and

Operational Amplifier for TFT LCD

________________________________________________________________ Maxim Integrated Products

1

Ordering Information

TO VCOM

BACKPLANE

FROM TCON

IN

FREQ

SHDN

COMP

LDO

FB

LX

GND

PGND

OUT

SUPB

GON

DRN

CTL

MODE

SS

POSB

NEGB

OUTB

THR

DLP

SRC

MAX8758

Simplified Operating Circuit

19-3699; Rev 1; 9/05

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

PART

TEMP RANGE

PIN-PACKAGE

MAX8758ETG

-40°C to +85°C

24 Thin QFN-EP*

4mm x 4mm

MAX8758ETG+

-40°C to +85°C

24 Thin QFN-EP*

4mm x 4mm

*EP = Exposed pad.

+Denotes lead-free package.

Pin Configuration appears at end of data sheet.

DualMode is a trademark of Maxim Integrated Products, Inc.