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DS3231_13 Datasheet, PDF (1/20 Pages) Maxim Integrated Products – Extremely Accurate I2C-Integrated RTC/TCXO/Crystal
DS3231
Extremely Accurate I2C-Integrated
RTC/TCXO/Crystal
General Description
The DS3231 is a low-cost, extremely accurate I2C real-
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
through an I2C bidirectional bus.
A precision temperature-compensated voltage refer-
ence and comparator circuit monitors the status of VCC
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 µP reset.
Applications
Servers
Telematics
Utility Power Meters
GPS
Pin Configuration appears at end of data sheet.
VCC
SCL
SDA
µP
RST
VCC
RPU = tR/CB
RPU
RPU
SCL
SDA
RST
PUSHBUTTON
N.C.
RESET
N.C.
N.C.
N.C.
Features
o Accuracy ±2ppm from 0°C to +40°C
o Accuracy ±3.5ppm from -40°C to +85°C
o Battery Backup Input for Continuous
Timekeeping
o Operating Temperature Ranges
Commercial: 0°C to +70°C
Industrial: -40°C to +85°C
o Low-Power Consumption
o Real-Time Clock Counts Seconds, Minutes,
Hours, Day, Date, Month, and Year with Leap Year
Compensation Valid Up to 2100
o Two Time-of-Day Alarms
o Programmable Square-Wave Output
o Fast (400kHz) I2C Interface
o 3.3V Operation
o Digital Temp Sensor Output: ±3°C Accuracy
o Register for Aging Trim
o RST Output/Pushbutton Reset Debounce Input
o Underwriters Laboratories (UL) Recognized
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
DS3231S#
0°C to +70°C
16 SO
DS3231SN#
-40°C to +85°C
16 SO
#Denotes an RoHS-compliant device that may include lead
(Pb) that is exempt under RoHS requirements. The lead finish
is JESD97 category e3, and is compatible with both lead-
based and lead-free soldering processes. A "#" anywhere on
the top mark denotes an RoHS-compliant device.
Typical Operating Circuit
VCC
VCC
DS3231
GND
INT/SQW
32kHz
VBAT
N.C.
N.C.
N.C.
N.C.
For pricing, delivery, and ordering information, please contact Maxim Direct at
1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.
19-5170; Rev 9; 1/13