________________General Description

The MAX823/MAX824/MAX825 microprocessor (µP)

supervisory circuits combine reset output, watchdog,

and manual reset input functions in 5-pin SOT23 and

SC70 packages. They significantly improve system relia-

bility and accuracy compared to separate ICs or discrete

components. The MAX823/MAX824/MAX825 are specifi-

Seven preprogrammed reset threshold voltages are

available (see Reset Threshold Table). All three devices

have an active-low reset output, which is guaranteed to

also offers a watchdog input and manual reset input.

The MAX824 offers a watchdog input and a comple-

mentary active-high reset. The MAX825 offers a manual

reset input and a complementary active-high reset. The

Selector Guide explains the functions offered in this

series of parts.

________________________Applications

Computers and Controllers

Embedded Controllers

Intelligent Instruments

Automotive Systems

Critical µP Monitoring

Portable/Battery-Powered Equipment

Features

♦ Precision Monitoring of +2.5V, +3V, +3.3V, and

+5V Power Supplies

♦ Operating Current: 6µA (MAX823L/M) (SC70)

2µA (MAX825T/S/R/Z/Y) (SC70)

♦ Fully Specified Over Temperature

♦ 140ms min Power-On Reset

♦ Power-Supply Transient Immunity

♦ Watchdog Timer with 1.6s Timeout

(MAX823/MAX824)

♦ Manual Reset Input (MAX823/MAX825)

♦ No External Components

5-Pin Microprocessor Supervisory Circuits With

Watchdog Timer and Manual Reset

________________________________________________________________ Maxim Integrated Products

1

1

5

2

3

4

1

5

2

3

4

1

5

2

3

4

GND

WDI

MAX823

SOT23/SC70

TOP VIEW

MR

RESET

GND

WDI

RESET

MAX824

SOT23/SC70

RESET

GND

MR

RESET

MAX825

SOT23/SC70

RESET

______________________Selector Guide

19-0487; Rev 5; 12/05

†Insert the desired suffix letter (from the Reset Threshold table) into

the blank to complete the part number. All devices are available in

tape-and-reel only. There is a 2500 piece minimum order increment.

Devices are available in both leaded and lead-free packaging.

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

MAX823

Active-Low Reset

✔

Active-High Reset

—

FUNCTION

Watchdog Input

✔

MAX824

✔

✔

✔

MAX825

✔

✔

—

Manual Reset Input

✔

—

✔

SUFFIX

RESET

THRESHOLD (V)

L

4.63

M

4.38

T

3.08

S

2.93

R

2.63

Typical Operating Circuit appears at end of data sheet.

Marking Information appears at end of data sheet.

Ordering Information

PART†

TEMP. RANGE

PIN-PACKAGE

MAX823_EXK-T

-40°C to +85°C

5 SC70-5

MAX823_EUK-T

-40°C to +125°C

5 SOT23-5

MAX824_EXK-T

-40°C to +85°C

5 SC70-5

Ordering Information continued at end of data sheet.

Reset Threshold Table

Z (SC70 only)

2.32

Y (SC70 only)

2.19

Pin Configurations

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.