___________Product Selection Guide

_______________General Description

The MAX787/MAX788/MAX789 are monolithic, bipolar,

pulse-width modulation (PWM), switch-mode, step-down

DC-DC regulators. Each is rated at 5A. Very few external

components are needed for standard operation because

the power switch, oscillator, feedback, and control circuitry

are all on-chip. Employing a classic buck topology, these

regulators perform high-current step-down functions.

The MAX787/MAX788/MAX789 have excellent dynamic

and transient response characteristics, while featuring

cycle-by-cycle current limiting to protect against overcurrent

faults and short-circuit output faults. They also have a wide

8V to 40V input range.

Each regulator is available in a 5-pin TO-220 package.

These devices have a preset 100kHz oscillator frequency

and a preset current limit of 6.5A. See the MAX724/

MAX726 data sheet for more applications information.

_______________________Applications

Distributed Power from High-Voltage Buses

High-Current, High-Voltage Step-Down

Multiple-Output Buck Converter

5V/3.3V/3V 5A Step-Down, PWM,

Switch-Mode DC-DC Regulators

________________________________________________________________

Maxim Integrated Products

1

GND

SENSE

CASE IS CONNECTED TO GROUND. STANDARD PACKAGE HAS STAGGERED LEADS.

CONTACT FACTORY FOR STRAIGHT LEADS.

5-PIN TO-220

FRONT VIEW

MAX787

MAX788

MAX789

1

2

3

4

5

__________________Pin Configuration

VIN

VC

VSW

220

µF

GND

2.7k

0.01

µF

OUTPUT

5V AT 5A

SENSE

50

µH

MBR745

470

µF

INPUT

8V TO 40V

MAX787

STEP-DOWN CONVERTER

__________Typical Operating Circuit

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

19-0182; Rev 3; 9/95

___________________________Features

o Input Range: Up to 40V

o 5A On-Chip Power Switch

o Fixed Outputs: 5V (MAX787)

3.3V (MAX788)

3V (MAX789)

o 100kHz Switching Frequency

o Excellent Dynamic Characteristics

o Few External Components

o 8.5mA Quiescent Current

o TO-220 Package

______________Ordering Information

PART

MAX724

Adjustable

5

MAX728

3.3

2

MAX726

Adjustable

2

MAX727

5

2

MAX787

5

5

MAX788

3.3

5

MAX789

3

5

MAX729

3

2

PART

MAX787CCK

MAX787ECK

MAX788CCK

MAX788ECK

-40°C to +85°C

0°C to +70°C

TEMP. RANGE

PIN-PACKAGE

5 TO-220

5 TO-220

-40°C to +85°C

0°C to +70°C

5 TO-220

5 TO-220

MAX789CCK

MAX789ECK

-40°C to +85°C

0°C to +70°C

5 TO-220

5 TO-220