2 DS3231 Extremely Accurate I C-Integrated RTC/TCXO/Crystal General Description Benefits and Features 2 The DS3231 is a low-cost, extremely accurate I C Highly Accurate RTC Completely Manages All real-time clock (RTC) with an integrated temperature- Timekeeping Functions compensated crystal oscillator (TCXO) and crystal. Real-Time Clock Counts Seconds, Minutes, Hours, The device incorporates a battery input, and maintains Date of the Month, Month, Day of the Week, and accurate timekeeping when main power to the device Year, with Leap-Year Compensation Valid Up to 2100 is interrupted. The integration of the crystal resonator Accuracy 2ppm from 0C to +40C enhances the long-term accuracy of the device as well Accuracy 3.5ppm from -40C to +85C as reduces the piece-part count in a manufacturing line. Digital Temp Sensor Output: 3C Accuracy The DS3231 is available in commercial and industrial Register for Aging Trim temperature ranges, and is offered in a 16-pin, 300-mil RST Output/Pushbutton Reset Debounce Input SO package. Two Time-of-Day Alarms Programmable Square-Wave Output Signal The RTC maintains seconds, minutes, hours, day, date, Simple Serial Interface Connects to Most month, and year information. The date at the end of the Microcontrollers month is automatically adjusted for months with fewer 2 Fast (400kHz) I C Interface than 31 days, including corrections for leap year. The Battery-Backup Input for Continuous Timekeeping clock operates in either the 24-hour or 12-hour format Low Power Operation Extends Battery-Backup with an AM/PM indicator. Two programmable time-of-day Run Time alarms and a programmable square-wave output are 3.3V Operation provided. Address and data are transferred serially 2 through an I C bidirectional bus. Operating Temperature Ranges: Commercial (0C to +70C) and Industrial (-40C to +85C) A precision temperature-compensated voltage reference and comparator circuit monitors the status of V to Underwriters Laboratories (UL) Recognized CC detect power failures, to provide a reset output, and to Applications automatically switch to the backup supply when necessary. Servers Utility Power Meters Additionally, the RST pin is monitored as a pushbutton Telematics GPS input for generating a P reset. Ordering Information and Pin Configuration appear at end of data sheet. Typical Operating Circuit V V CC CC R = t /C PU R B V CC R R PU PU V CC SCL SCL INT/SQW SDA SDA 32kHz P V BAT RST RST DS3231 PUSHBUTTON N.C. N.C. RESET N.C. N.C. N.C. N.C. GND N.C. N.C. Underwriters Laboratories is a registered certification mark of Underwriters Laboratories Inc. 19-5170 Rev 10 3/152 DS3231 Extremely Accurate I C-Integrated RTC/TCXO/Crystal Absolute Maximum Ratings Voltage Range on Any Pin Relative to Ground ....-0.3V to +6.0V Junction Temperature ......................................................+125C Storage Temperature Range .............................. -40C to +85C Junction-to-Ambient Thermal Resistance ( ) (Note 1) 73C/W JA Lead Temperature (soldering, 10s) .................................+260C Junction-to-Case Thermal Resistance ( ) (Note 1) ....23C/W JC Soldering Temperature (reflow, 2 times max) .................+260C Operating Temperature Range (see the Handling, PCB Layout, and Assembly section) DS3231S ............................................................0C to +70C DS3231SN ...................................................... -40C to +85C Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial. Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Recommended Operating Conditions (T = T to T , unless otherwise noted.) (Notes 2, 3) A MIN MAX PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS V 2.3 3.3 5.5 V CC Supply Voltage V 2.3 3.0 5.5 V BAT 0.7 x V + CC Logic 1 Input SDA, SCL V V IH V 0.3 CC 0.3 x Logic 0 Input SDA, SCL V -0.3 V IL V CC Electrical Characteristics (V = 2.3V to 5.5V, V = Active Supply (see Table 1), T = T to T , unless otherwise noted.) (Typical values are at V = CC CC A MIN MAX CC 3.3V, V = 3.0V, and T = +25C, unless otherwise noted.) (Notes 2, 3) BAT A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS V = 3.63V 200 CC Active Supply Current I (Notes 4, 5) A CCA V = 5.5V 300 CC 2 I C bus inactive, 32kHz V = 3.63V 110 CC Standby Supply Current I output on, SQW output off A CCS V = 5.5V 170 (Note 5) CC 2 V = 3.63V 575 I C bus inactive, 32kHz CC Temperature Conversion Current I A CCSCONV output on, SQW output off V = 5.5V 650 CC Power-Fail Voltage V 2.45 2.575 2.70 V PF Logic 0 Output, 32kHz, INT/SQW, V I = 3mA 0.4 V OL OL SDA Logic 0 Output, RST V I = 1mA 0.4 V OL OL Output Leakage Current 32kHz, I Output high impedance -1 0 +1 A LO INT/SQW, SDA Input Leakage SCL I -1 +1 A LI RST Pin I/O Leakage I RST high impedance (Note 6) -200 +10 A OL V Leakage Current BAT I 25 100 nA BATLKG (V Active) CC Maxim Integrated 2 www.maximintegrated.com