DS3232M

±5ppm, I2C Real-Time Clock with SRAM

General Description

The DS3232M is a low-cost, extremely accurate, I2C

real-time clock (RTC) with 236 bytes of battery-backed

SRAM. The device incorporates a battery input and

maintains accurate timekeeping when main power to the

device is interrupted. The integration of the microelec-

tromechanical systems (MEMS) resonator enhances the

long-term accuracy of the device and reduces the piece-

part count in a manufacturing line.

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 1Hz output are provided. Address and data

are transferred serially through an I2C bidirectional bus.

A precision temperature-compensated voltage reference

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 neces-

sary. Additionally, the RST pin is monitored as a pushbut-

ton input for generating a microprocessor reset. See the

Block Diagram for more details.

Applications

Power Meters

Industrial Applications

Features

S

Timekeeping Accuracy ±5ppm (±0.432 Second/

Day) from -40NC to +85NC

S

236 Bytes of Battery-Backed User SRAM

S

Battery Backup for Continuous Timekeeping

S

Low Power Consumption

S

Functionally Compatible to DS3232

S

Complete Clock Calendar Functionality Including

Seconds, Minutes, Hours, Day, Date, Month, and

Year with Leap Year Compensation Up to Year

2100

S

Two Time-of-Day Alarms

S

1Hz and 32.768kHz Outputs

S

Reset Output and Pushbutton Input with

Debounce

S

Fast (400kHz) I2C-Compatible Serial Bus

S

+2.3V to +4.5V Supply Voltage

S

Digital Temp Sensor with ±3NC Accuracy

S

-40NC to +85NC Temperature Range

S

8-Pin SO (150 mils) Package

S

Underwriters Laboratories (UL) Recognized

Typical Operating Circuit

19-6247; Rev 2; 7/13

Ordering Information appears at end of data sheet.

Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device may

be simultaneously available through various sales channels. For information about device errata, go to: www.maximintegrated.com/errata.

For related parts and recommended products to use with this part, refer to: www.maximintegrated.com/DS3232M.related

DS3232M

SCL

SDA

32KHZ

VBAT

VCC

VCC

CPU

I/O PORT

INTERRUPTS

INT/SQW

RST

PUSH-

BUTTON

RESET

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.