General Description

The MAX1806 low-dropout linear regulator operates

from a +2.25V to +5.5V supply and delivers a guaran-

teed 500mA load current with low 175mV dropout. The

high-accuracy (±1%) output voltage is preset at an

internally trimmed voltage (see Selector Guide) or can

be adjusted from +0.8V to +4.5V with an external resis-

tive-divider.

An internal PMOS pass transistor allows low 210µA

supply current, making this device ideal for portable

equipment such as personal digital assistants (PDAs),

cellular phones, cordless phones, and other equip-

ment, including base stations and docking stations.

Other features include an active-low, power-OK output

that indicates when the output is out of regulation, a

0.02µA shutdown mode, short-circuit protection, and

thermal shutdown protection. The MAX1806 comes in a

miniature 1.3W, 8-pin power-µMAX package with a

metal pad on the underside of the package.

Applications

Notebook Computers

Cellular and Cordless Telephones

PDAs

Palmtop Computers

Base Stations

USB Hubs

Docking Stations

Features

o Guaranteed 500mA Output Current

o Output Down to 0.8V

o Low 175mV Dropout at 500mA

o ±1% Output Voltage Accuracy

Preset at 0.8V, 1.5V, 1.8V, 2.5V, or 3.3V

Adjustable from 0.8V to 4.5V

o Power-OK Output

o Low 210µA Ground Current

o 0.02µA Shutdown Current

o Thermal Overload Protection

o Output Current Limit

o Tiny 1.3W, 8-Pin Power-µMAX Package

500mA, Low-Voltage Linear Regulator in µMAX

________________________________________________________________ Maxim Integrated Products

1

SET

GND

SHDN

1

2

8

7

OUT

OUT

IN

POK

IN

µMAX

TOP VIEW

3

4

6

5

MAX1806

Pin Configuration

Ordering Information

NC

MAX1806

IN

1

µF

10

µF

100k

Ω

+2.25V TO +5.5V

ON

OFF

SHDN

OUT

0.8V TO 4.5V

POK

GND

SET

TO

µC

Typical Operating Circuit

19-2018; Rev 0; 4/01

PART

TEMP. RANGE

PIN-PACKAGE

MAX1806EUA_ _

-40

°C to +85°C

8 Power-

µMAX

Selector Guide

PART AND SUFFIX

TOP MARK

MAX1806EUA33

3.3

AAAG

MAX1806EUA25

2.5

AAAH

MAX1806EUA18

1.8

AAAI

MAX1806EUA15

1.5

AAAJ

MAX1806EUA08

0.8

AAAK

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.