DS3232_08 Datasheet, PDF (1/19 Pages) Maxim Integrated Products – Extremely Accurate I2C RTC with Integrated Crystal and SRAM

Rev 4; 10/08
Extremely Accurate I²C RTC with
Integrated Crystal and SRAM
General Description
The DS3232 is a low-cost temperature-compensated
crystal oscillator (TCXO) with a very accurate, tempera-
ture-compensated, integrated real-time clock (RTC) and
236 bytes of battery-backed SRAM. Additionally, the
DS3232 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 DS3232
is available in commercial and industrial temperature
ranges, and is offered in an industry-standard 20-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 V_CC
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.
Servers
Telematics
Applications
Utility Power Meters
GPS
Typical Operating Circuit
V_CC
R_PU = t_R / C_B
V_CC
R_PU
R_PU
SCL
SCL
SDA
SDA
RST
RST
μP
PUSH-
BUTTON
N.C.
RESET
N.C.
N.C.
N.C.
N.C.
N.C.
V_CC
V_CC
INT/SQW
32kHz
V_BAT
DS3232 ^N.C.
N.C.
N.C.
N.C.
GND
N.C.
UL is a registered trademark of Underwriters Laboratories, Inc.
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
♦ 236 Bytes of Battery-Backed SRAM
♦ Low-Power Consumption
♦ Real-Time Clock Counts Seconds, Minutes,
Hours, Day, Date, Month, and Year with Leap Year
Compensation Valid Up to 2099
♦ Two Time-of-Day Alarms
♦ Programmable Square-Wave Output
♦ Fast (400kHz) I²C Interface
♦ 3.3V Operation
♦ Digital Temp Sensor Output: ±3°C Accuracy
♦ Register for Aging Trim
♦ RST Input/Output
♦ 300-Mil, 20-Pin SO Package
♦ Underwriters Laboratories (UL^®) Recognized
Ordering Information
PART
TEMP RANGE
PIN-
PACKAGE
TOP
MARK
DS3232S#
0°C to +70°C 20 SO
DS3232
DS3232SN# -40°C to +85°C 20 SO
DS3232N
# Denotes a RoHS-compliant device that may include lead that
is exempt under the RoHS requirements. 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 a RoHS-compliant device.
Pin Configuration
TOP VIEW
N.C. 1
N.C. 2
32kHz 3
VCC 4
INT/SQW 5
RST 6
N.C. 7
N.C. 8
N.C. 9
N.C. 10
DS3232
20 SCL
19 N.C.
18 SCL
17 SDA
16 V_BAT
15 GND
14 N.C.
13 N.C.
12 N.C.
11 N.C.
SO
______________________________________________ Maxim Integrated Products 1
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.