_______________General Description

The MAX603/MAX604 low-dropout, low quiescent cur-

rent, linear regulators supply 5V, 3.3V, or an adjustable

output for currents up to 500mA. They are available in a

1.8W SO package. Typical dropouts are 320mV at 5V

and 500mA, or 240mV at 3.3V and 200mA. Quiescent

currents are 15µA typ and 35µA max. Shutdown turns

off all circuitry and puts the regulator in a 2µA off mode.

A unique protection scheme limits reverse currents

when the input voltage falls below the output. Other fea-

tures include foldback current limiting and thermal

overload protection.

The output is preset at 3.3V for the MAX604 and 5V for

the MAX603. In addition, both devices employ Dual

Mode™ operation, allowing user-adjustable outputs

from 1.25V to 11V using external resistors. The input

voltage supply range is 2.7V to 11.5V.

The MAX603/MAX604 feature a 500mA P-channel

MOSFET pass transistor. This transistor allows the

devices to draw less than 35µA over temperature, inde-

pendent of the output current. The supply current

remains low because the P-channel MOSFET pass tran-

sistor draws no base currents (unlike the PNP transis-

tors of conventional bipolar linear regulators). Also,

when the input-to-output voltage differential becomes

small, the internal P-channel MOSFET does not suffer

from excessive base current losses that occur with sat-

urated PNP transistors.

________________________Applications

5V and 3.3V Regulators

1.25V to 11V Adjustable Regulators

Battery-Powered Devices

Pagers and Cellular Phones

Portable Instruments

Solar-Powered Instruments

____________________________Features

o 500mA Output Current, with Foldback Current

Limiting

o High-Power (1.8W) 8-Pin SO Package

o Dual Mode™ Operation: Fixed or Adjustable

Output from 1.25V to 11V

o Large Input Range (2.7V to 11.5V)

o Internal 500mA P-Channel Pass Transistor

o 15µA Typical Quiescent Current

o 2µA (Max) Shutdown Mode

o Thermal Overload Protection

o Reverse-Current Protection

______________Ordering Information

** Contact factory for availability.

5V/3.3V or Adjustable, Low-Dropout,

________________________________________________________________

Maxim Integrated Products

1

1

2

3

4

8

7

6

5

OUT

GND

GND

SET

IN

GND

GND

OFF

MAX603

MAX604

DIP/SO

TOP VIEW

__________________Pin Configuration

MAX603

MAX604

OUT

SET

GND

IN

OFF

10

µF

10

µF

BATTERY

OUTPUT

VOLTAGE

__________Typical Operating Circuit

Call toll free 1-800-998-8800 for free samples or literature.

19-0269; Rev 0; 9/94

PART

MAX603CPA

MAX603CSA

MAX603C/D

0°C to +70°C

0°C to +70°C

0°C to +70°C

TEMP. RANGE

PIN-PACKAGE

8 Plastic DIP

8 SO

Dice*

MAX603EPA

MAX603ESA

-40°C to +85°C

-40°C to +85°C

8 Plastic DIP

8 SO

MAX603MJA

-55°C to +125°C

8 CERDIP**

MAX604CPA

MAX604CSA

MAX604C/D

0°C to +70°C

0°C to +70°C

0°C to +70°C

8 Plastic DIP

8 SO

Dice*

MAX604EPA

MAX604ESA

-40°C to +85°C

-40°C to +85°C

8 Plastic DIP

8 SO

MAX604MJA

-55°C to +125°C

8 CERDIP**

™ Dual Mode is a trademark of Maxim Integrated Products.