General Description

time clock (RTC) with an integrated temperature-

compensated crystal oscillator (TCXO) and crystal. The

device incorporates a battery input, and maintains accu-

rate timekeeping when main power to the device is inter-

rupted. The integration of the crystal resonator enhances

the long-term accuracy of the device as well as reduces

the piece-part count in a manufacturing line. The DS3231

is available in commercial and industrial temperature

ranges, and is offered in a 16-pin, 300-mil SO package.

The RTC maintains seconds, minutes, hours, day, date,

month, and year information. The date at the end of the

month is automatically adjusted for months with fewer

than 31 days, including corrections for leap year. The

clock operates in either the 24-hour or 12-hour format

with an AM/PM indicator. Two programmable time-of-

day alarms and a programmable square-wave output

are provided. Address and data are transferred serially

A precision temperature-compensated voltage refer-

to detect power failures, to provide a reset output, and

to automatically switch to the backup supply when nec-

essary. Additionally, the RST pin is monitored as a

pushbutton input for generating a reset externally.

Applications

Servers

Utility Power Meters

Telematics

GPS

Features

♦ Accuracy ±2ppm from 0°C to +40°C

♦ Accuracy ±3.5ppm from -40°C to +85°C

♦ Battery Backup Input for Continuous

Timekeeping

♦ Operating Temperature Ranges

Commercial: 0°C to +70°C

Industrial: -40°C to +85°C

♦ Low-Power Consumption

♦ Real-Time Clock Counts Seconds, Minutes,

Hours, Day, Date, Month, and Year with Leap Year

Compensation Valid Up to 2100

♦ Two Time-of-Day Alarms

♦ Programmable Square-Wave Output

♦ 3.3V Operation

♦ Digital Temp Sensor Output: ±3°C Accuracy

♦ Register for Aging Trim

♦ RST Input/Output

♦ UL Recognized

RTC/TCXO/Crystal

______________________________________________ Maxim Integrated Products

1

Rev 2; 6/05

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.

Ordering Information

PART

TEMP RANGE

PIN-PACKAGE

TOP

MARK

DS3231S

0°C to +70°C

16 SO

DS3231

DS3231SN

-40°C to +85°C

16 SO

DS3231N

DS3231S+

0°C to +70°C

16 SO

DS3231+

DS3231SN+

-40°C to +85°C

16 SO

DS3231N+

Pin Configuration appears at end of data sheet.

Standard Specification as defined by Philips.

DS3231

SCL

INT/SQW

32kHz

PUSHBUTTON

RESET

SDA

RST

N.C.

N.C.

N.C.

N.C.

GND

CPU

N.C.

N.C.

N.C.

N.C.

Typical Operating Circuit

+Denotes lead-free