_______________General Description

The MAX782 is a system-engineered power-supply con-

troller for notebook computers or similar battery-powered

equipment. It provides two high-performance step-down

(buck) pulse-width modulators (PWMs) for +3.3V and +5V,

and dual PCMCIA VPP outputs powered by an integral fly-

back winding controller. Other functions include dual, low-

dropout, micropower linear regulators for CMOS/RTC back-

up, and three precision low-battery-detection comparators.

High efficiency (95% at 2A; greater than 80% at loads

from 5mA to 3A) is achieved through synchronous recti-

fication and PWM operation at heavy loads, and Idle-

small components, thanks to high operating frequen-

cies (300kHz/200kHz) and a new current-mode PWM

architecture that allows for output filter capacitors as

small as 30µF per ampere of load. Line- and load-tran-

sient response are terrific, with a high 60kHz unity-gain

crossover frequency allowing output transients to be

corrected within four or five clock cycles. Low system

cost is achieved through a high level of integration and

the use of low-cost, external N-channel MOSFETs. The

integral flyback winding controller provides a low-cost,

+15V high-side output that regulates even in the

absence of a load on the main output.

Other features include low-noise, fixed-frequency PWM

operation at moderate to heavy loads and a synchroniz-

able oscillator for noise-sensitive applications such as

electromagnetic pen-based systems and communicat-

ing computers. The MAX782 is a monolithic BiCMOS IC

available in fine-pitch, SSOP surface-mount packages.

_______________________Applications

Notebook Computers

Portable Data Terminals

Communicating Computers

Pen-Entry Systems

___________________________Features

o Dual PWM Buck Controllers (+3.3V and +5V)

o Dual PCMCIA VPP Outputs (0V/5V/12V)

o Three Precision Comparators or Level Translators

o 95% Efficiency

o 420µA Quiescent Current;

70µA in Standby (linear regulators alive)

o 5.5V to 30V Input Range

o Small SSOP Package

o Fixed Output Voltages Available:

3.3 (standard)

3.45 (High-Speed Pentium™)

3.6 (PowerPC™)

______________Ordering Information

Triple-Output Power-Supply

Controller for Notebook Computers

________________________________________________________________

Maxim Integrated Products

1

36

35

34

33

32

31

30

29

28

27

26

25

24

23

1

2

3

4

5

6

7

8

9

10

11

12

13

14

SS3

CS3

FB3

DH3

LX3

BST3

LX5

DL3

V+

VL

FB5

PGND

DL5

BST5

SYNC

REF

GND

VPPB

VDD

VPPA

Q1

Q2

Q3

VH

D3

D2

D1

ON3

SSOP

TOP VIEW

MAX782

22

21

20

19

15

16

17

18

ON5

DH5

CS5

SS5

DB0

DB1

DA0

DA1

__________________Pin Configuration

MAX782

5.5V

TO

30V

VPP

CONTROL

ON3

ON5

SYNC

POWER

SECTION

SUSPEND POWER

LOW-BATTERY WARNING

VPP (0V/5V/12V)

µP

MEMORY

PERIPHERALS

+3.3V

+5V

DUAL

PCMCIA

SLOTS

4

VPP (0V/5V/12V)

______Typical Application Diagram

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

19-0146; Rev 2; 5/94

PART

TEMP. RANGE

PIN-PACKAGE

MAX782CBX

0°C to +70°C

36 SSOP

MAX782RCBX

0°C to +70°C

36 SSOP

MAX782SCBX

0°C to +70°C

36 SSOP

™

Idle-Mode is a trademark of Maxim Integrated Products. Pentium is a trademark of Intel. PowerPC is a trademark of IBM.

Evaluation

Kit

Information

Included

Ordering Information continued on last page.

3.3V

3.45V

3.6V