Product Details
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 accurate timekeeping when main power to the device is interrupted. 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 active-low 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 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 necessary. Additionally, the active-low RST pin is monitored as a pushbutton input for generating a µP reset.
Key Features
- Highly Accurate RTC Completely Manages All Timekeeping Functions
- Real-Time Clock Counts Seconds, Minutes, Hours, Date of the Month, Month, Day of the Week, and Year, with Leap-Year Compensation Valid Up to 2100
- Accuracy ±2ppm from 0°C to +40°C
- Accuracy ±3.5ppm from -40°C to +85°C
- Digital Temp Sensor Output: ±3°C Accuracy
- Register for Aging Trim
- Active-Low RST Output/Pushbutton Reset Debounce Input
- Two Time-of-Day Alarms
- Programmable Square-Wave Output Signal
- Simple Serial Interface Connects to Most Microcontrollers
- Fast (400kHz) I2C Interface
- Battery-Backup Input for Continuous Timekeeping
- Low Power Operation Extends Battery-Backup Run Time
- 3.3V Operation
- Operating Temperature Ranges: Commercial (0°C to +70°C) and Industrial (-40°C to +85°C)
- Underwriters Laboratories® (UL) Recognized
Applications/Uses
- Global Positioning Systems (GPS)
- Servers
- Telematics
- Utility Power Meters
Frequency | 32.768kHz |
Osc. Type | TCXO |
Tuning Adjustment Type | Digital |
Frequency Output Type | CMOS Open-Drain |
Frequency Stability (±ppm/yr) (0 to +40°C) | 2 |
Frequency Stability (±ppm/yr) (-40 to 0°C/ +40 to +85°C) | 3.5 |
Frequency Stability (±ppm/yr) (vs. VCC) | 1 (typ) |
Frequency Stability (±ppm) (vs. Aging) | 5 (0-10 Years) |
VSUPPLY (V) | 2.3 to 5.5 |
Package/Pins | SOIC (W)/16 |
Budgetary Price (See Notes) | $4.04 @1k |
Interface | I2C |
Date/ Time Format (hh = sec/100) | YY-MM-DD/ HH:MM:SS |
Time Keeping Current (nA) (typ) | 840 |
Memory Type | None |
Time of Day Alarms | 2 |
Integrated Resonator | XTAL |
Package/Pins | SOIC (W)/16 |
Technical Docs
Click any title below to view the detail page where available.
Why on Earth Don’t You Include a Clock in Your Design?

Description
Maxim Analog Essentials is a collection of peripheral modules which can plug directly into any FPGA/CPU expansion port which follows the Pmod™ standard established by Digilent, Inc. The collection includes modules containing a wide variety of commonly used analog and mixed signal functions. The modules are supported by software which includes FPGA configuration files for three popular FPGA platforms: Avnet LX-9, Digilent Nexys 3 and Avnet ZEDBoard, as well as example programs to exercise and demonstrate each module. While the example programs demonstrate the module’s functionality, they are well partitioned and documented allowing the core routines to be easily cut and pasted into your own programs. The combination of plug-in simplicity and easy software integration allows for quick migration from idea to working prototype.
View DetailsFeatures
- Data Converter, Interface, Clock, Sensor, and Other Modules Included to Address Many Design Needs
- Plug in Modules Enable Rapid Hardware Prototyping
- Proven Software Drivers Reduce Development Time
- FPGA Configuration Files Included to Simplify Design Effort
![]() | SIMULATION MODELS DS3231 IBIS Model | Download |
Support & Training
Search our knowledge base for answers to your technical questions.
Filtered SearchOur dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal
Parameters
Frequency | 32.768kHz |
Osc. Type | TCXO |
Tuning Adjustment Type | Digital |
Frequency Output Type | CMOS Open-Drain |
Frequency Stability (±ppm/yr) (0 to +40°C) | 2 |
Frequency Stability (±ppm/yr) (-40 to 0°C/ +40 to +85°C) | 3.5 |
Frequency Stability (±ppm/yr) (vs. VCC) | 1 (typ) |
Frequency Stability (±ppm) (vs. Aging) | 5 (0-10 Years) |
VSUPPLY (V) | 2.3 to 5.5 |
Package/Pins | SOIC (W)/16 |
Budgetary Price (See Notes) | $4.04 @1k |
Interface | I2C |
Date/ Time Format (hh = sec/100) | YY-MM-DD/ HH:MM:SS |
Time Keeping Current (nA) (typ) | 840 |
Memory Type | None |
Time of Day Alarms | 2 |
Integrated Resonator | XTAL |
Package/Pins | SOIC (W)/16 |
Key Features
- Highly Accurate RTC Completely Manages All Timekeeping Functions
- Real-Time Clock Counts Seconds, Minutes, Hours, Date of the Month, Month, Day of the Week, and Year, with Leap-Year Compensation Valid Up to 2100
- Accuracy ±2ppm from 0°C to +40°C
- Accuracy ±3.5ppm from -40°C to +85°C
- Digital Temp Sensor Output: ±3°C Accuracy
- Register for Aging Trim
- Active-Low RST Output/Pushbutton Reset Debounce Input
- Two Time-of-Day Alarms
- Programmable Square-Wave Output Signal
- Simple Serial Interface Connects to Most Microcontrollers
- Fast (400kHz) I2C Interface
- Battery-Backup Input for Continuous Timekeeping
- Low Power Operation Extends Battery-Backup Run Time
- 3.3V Operation
- Operating Temperature Ranges: Commercial (0°C to +70°C) and Industrial (-40°C to +85°C)
- Underwriters Laboratories® (UL) Recognized
Applications/Uses
- Global Positioning Systems (GPS)
- Servers
- Telematics
- Utility Power Meters
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 accurate timekeeping when main power to the device is interrupted. 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 active-low 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 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 necessary. Additionally, the active-low RST pin is monitored as a pushbutton input for generating a µP reset.
Technical Docs
Support & Training
Search our knowledge base for answers to your technical questions.
Filtered SearchOur dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal