General Description

The MAX6730–MAX6735 single-/dual-/triple-voltage

microprocessor (µP) supervisors feature a watchdog

timer and manual reset capability. The MAX6730–

MAX6735 offer factory-set reset thresholds for monitor-

ing voltages from +0.9V to +5V and an adjustable reset

input for monitoring voltages down to +0.63V. The com-

bination of these features significantly improves system

reliability and accuracy when compared to separate

ICs or discrete components.

The active-low reset output asserts and remains asserted

for the reset timeout period after all the monitored volt-

ages exceed their respective thresholds. Multiple factory-

set reset threshold combinations reduce the number of

external components required. The MAX6730/MAX6731

monitor a single fixed voltage, the MAX6732/MAX6733

monitor two fixed voltages, and the MAX6734/MAX6735

monitor two fixed voltages and one adjustable voltage. All

devices are offered with six minimum reset timeout peri-

ods ranging from 1.1ms to 1120ms.

The MAX6730–MAX6735 feature a watchdog timer with

an independent watchdog output. The watchdog timer

prevents system lockup during code execution errors.

A watchdog startup delay of 54s after reset asserts

allows system initialization during power-up. The watch-

dog operates in normal mode with a 1.68s delay after

initialization. The MAX6730/MAX6732/MAX6734 provide

an active-low, open-drain watchdog output. The

MAX6731/MAX6733/MAX6735 provide an active-low,

push-pull watchdog output.

Other features include a manual reset input (MAX6730/

MAX6731/MAX6734/MAX6735) and push-pull reset out-

put (MAX6731/MAX6733/MAX6735) or open-drain reset

output (MAX6730/MAX6732/MAX6734). The MAX6730–

MAX6733 are offered in a tiny SOT23-6 package. The

MAX6734/MAX6735 are offered in a space-saving

SOT23-8 package. All devices are fully specified over

the extended -40°C to +85°C temperature range.

Applications

Multivoltage Systems

Telecom/Networking Equipment

Computers/Servers

Portable/Battery-Operated Equipment

Industrial Equipment

Printer/Fax

Set-Top Boxes

Features

from +1.575V to +4.63V

Voltages from +0.79V to +3.08V

o Adjustable RSTIN Threshold for Monitoring

Voltages Down to +0.63V (MAX6734/MAX6735 Only)

o Six Reset Timeout Options

o Watchdog Timer with Independent Watchdog Output

35s (min) Initial Watchdog Startup Period

1.12s (min) Normal Watchdog Timeout Period

o Manual Reset Input

(MAX6730/MAX6731/MAX6734/MAX6735)

o Guaranteed Reset Valid down to

o Push-Pull RESET or Open-Drain RESET Output

o Low Supply Current: 14µA (typ) at +3.6V

o Small 6-Pin and 8-Pin SOT23 Packages

Single-/Dual-/Triple-Voltage µP Supervisory

Circuits with Independent Watchdog Output

________________________________________________________________

Maxim Integrated Products

1

Ordering Information

19-2629; Rev 6; 11/11

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

*

after “UT” or “KA.” For the MAX6730/MAX6731, insert only the

delay (Table 2) after “D” to complete the part number. For exam-

out period. Sample stock is generally held on standard versions

only (see the Standard Versions table). Standard versions have

an order increment requirement of 2500 pieces. Nonstandard

versions have an order increment requirement of 10,000 pieces.

Contact factory for availability.

PART*

TEMP RANGE

PIN-PACKAGE

MAX6730UT_D_ -T

-40°C to +85°C

6 SOT23

MAX6731UT_D_ -T

-40°C to +85°C

6 SOT23

MAX6732UT_ _D_ -T

-40°C to +85°C

6 SOT23

MAX6733UT_ _D_ -T

-40°C to +85°C

6 SOT23

MAX6734KA_ _D_ -T

-40°C to +85°C

8 SOT23

MAX6734KA_ _D_ /V-T

-40°C to +85°C

8 SOT23

MAX6735KA_ _D_ -T

-40°C to +85°C

8 SOT23

Typical Operating Circuit and Pin Configurations appear at

end of data sheet.

Devices are available in both leaded and lead(Pb)-free/RoHS-

compliant packaging.

Specify lead-free by replacing “-T” with “+T” when ordering.

/V Denotes an automotive qualified part.