DS3231:Extremely Accurate I²C-Integrated RTC/TCXO/Crystal

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
DS3231: Block Diagram
DS3231: Block Diagram
Applications/Uses
  • Global Positioning Systems (GPS)
  • Servers
  • Telematics
  • Utility Power Meters
DataSheet
titleDownload file
DS3231 Data SheetDS3231.pdf
Parametrics
Part NumberFreq.Osc. TypeTuning Adjustment TypeFreq. Output TypeFrequency Stability
(±ppm/yr)
Frequency Stability
(±ppm/yr)
Frequency Stability
(±ppm/yr)
Frequency Stability
(±ppm)
VSUPPLY
(V)
Package/PinsBudgetary
Price
0 to +40°C-40 to 0°C/ +40 to +85°Cvs. VCCvs. AgingSee Notes
DS323132.768kHzTCXODigitalCMOS Open-Drain23.51 (typ)5 (0-10 Years)2.3 to 5.5SOIC/16$3.85 @1k

Part NumberInterfaceVSUPPLY
(V)
Time Keeping Current
(nA)
Memory TypeTime of Day AlarmsIntegrated ResonatorFunctionsPackage/PinsBudgetary
Price
typSee Notes
DS3231I2C2.3 to 5.5840None2XTALRTCSOIC/16$3.85 @1k
Design kits & evaluation modules
Quality and Environmental Data
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
DS3231SNo Longer AvailableDS3231S#SOIC,;16 pin;SOIC (;16 pin0°C to +70°CNo
DS3231S#ActiveSOIC,;16 pin;SOIC (;16 pin0°C to +70°C
DS3231S#T&RActiveSOIC,;16 pin;SOIC (;16 pin0°C to +70°C
DS3231S/T&RNo Longer AvailableDS3231S#T&RSOIC,;16 pin;SOIC;16 pin0°C to +70°CNo
DS3231SNNo Longer AvailableDS3231SN#SOIC,;16 pin;SOIC (;16 pin-40°C to +85°CNo
DS3231SN#ActiveSOIC,;16 pin;SOIC (;16 pin-40°C to +85°C
DS3231SN#T&RActiveSOIC,;16 pin;SOIC (;16 pin-40°C to +85°C
DS3231SN/T&RNo Longer AvailableDS3231SN#T&RSOIC,;16 pin;SOIC (;16 pin-40°C to +85°CNo
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