DS1341/DS1342 2 Low-Current I C RTCs for High-ESR Crystals General Description Features The DS1341/DS1342 low-current real-time clocks (RTCs) S Low Timekeeping Current of 250nA (typ) are timekeeping devices that provide an extremely low S Compatible with Crystal ESR Up to 100kI standby current, which permits longer life from a power S Use Crystals with C = 6pF (DS1341) or L supply. The DS1341/DS1342 support high-ESR crystals, C = 12.5pF (DS1342) L which broaden the pool of usable crystals for the devices. S +1.8V to +5.5V Operating Voltage Range The DS1341 uses a 6pF crystal, while the DS1342 uses a 12.5pF crystal. These devices are accessed through an S Maintain Time Down to +1.15V (typ) 2 I C serial interface. Other features include two time-of-day 2 S Fast (400kHz) I C Interface alarms, two interrupt outputs, a programmable square- S Bus Timeout for Lockup-Free Operation wave output, and a serial bus timeout mechanism. S RTC Counts Seconds, Minutes, Hours, Day, Date, The clock/calendar provides seconds, minutes, hours, Month, and Year with Leap Year Compensation day, date, month, and year information. The date at the Valid Through 2099 end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap S External Clock Source for Synchronization Clock year. The clock operates in either 24hr or 12hr format Reference (e.g., 32kHz, 50Hz/60Hz Power Line, with an AM/PM indicator. GPS 1PPS) The DS1341/DS1342 also include an input for synchroni- S Two Time-of-Day Alarms with Two Interrupt zation. When a reference clock (e.g., 60Hz power line or Outputs GPS 1PPS) is present at the CLKIN pin and the enable S Programmable Square-Wave Output external clock input bit (ECLK) is set to 1, the DS1341/ S Industrial Temperature Range DS1342 RTCs are frequency-locked to the external clock and the clock accuracy is determined by the external S Small, 8-Pin SOP or TDFN Packages source. In case of external clock failure, the clock is switched to the crystal oscillator. Applications The devices are available in lead(Pb)-free/RoHS- Medical Portable Instruments compliant, 8-pin FSOP or TDFN packages. The devices Point of Sale (POS) Portable Audio support a -40NC to +85NC extended temperature range. Telematics Automotive Ordering Information Typical Operating Circuit PIN- OSC PART TEMP RANGE PACKAGE C (pF) V V L CC CC DS1341U+ -40NC to +85NC 8 FSOP 6 DS1341U+T&R -40NC to +85NC 8 FSOP 6 R R R PU PU PU DS1341T+ -40NC to +85NC 8 TDFN-EP* 6 V CC SCL X1 DS1341T+T&R -40NC to +85NC 8 TDFN-EP* 6 SDA CLKIN/INTA DS1342U+ -40NC to +85NC 8 FSOP 12.5 CPU SQW/INTB X2 DS1342U+T&R -40NC to +85NC 8 FSOP 12.5 DS1342T+ 8 TDFN-EP* 12.5 -40NC to +85NC DS1341/DS1342 DS1342T+T&R 8 TDFN-EP* 12.5 -40NC to +85NC GND +Denotes a lead(Pb)-free/RoHS-compliant package. T&R = Tape and reel. *EP = Exposed pad. For pricing, delivery, and ordering information, please contact Maxim Direct at 19-4998 Rev 2 1/12 1-888-629-4642, or visit Maxim Integrateds website at www.maximintegrated.com.DS1341/DS1342 Low-Current I2C RTCs for High-ESR Crystals ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground ....-0.3V to +6.0V Storage Temperature Range ............................ -55NC to +125NC Operating Temperature Range .......................... -40NC to +85NC Lead Temperature (soldering, 10s) ................................+300NC Junction Temperature Maximum .....................................+150NC Soldering Temperature (reflow) ......................................+260NC PACKAGE THERMAL CHARACTERISTICS (Note 1) FSOP TDFN Junction-to-Ambient Thermal Resistance (B ) .....206.3NC/W Junction-to-Ambient Thermal Resistance (B ) ..........41NC/W JA JA Junction-to-Case Thermal Resistance (B ) ...............42NC/W Junction-to-Case Thermal Resistance (B ) .................8NC/W JC JC 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. DC ELECTRICAL CHARACTERISTICS (V = +1.8V to +5.5V, T = -40NC to +85NC, unless otherwise noted.) (Note 2) CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS V Full operation (Note 3) 1.8 5.5 CC Operating Voltage Range V V Timekeeping (Notes 3, 4) 1.3 5.5 CCT Minimum Timekeeping Voltage V T = +25NC (Notes 3, 4) 1.15 1.3 V CCTMIN A V = +3.0V, EGFIL = 0, DOSF = 1 220 500 CC Timekeeping Current: DS1341 V = +5.5V 250 600 CC CLKIN = GND or CLKIN = V I nA CC CCT V = +3.0V, EGFIL = 1, DOSF = 0 280 560 CC (Note 4) V = +5.5V 320 700 CC V = +3.0V, EGFIL = 0, DOSF = 1 250 600 CC Timekeeping Current: DS1342 V = +5.5V 280 700 CC CLKIN = GND or CLKIN = V I nA CC CCT V = +3.0V, EGFIL = 1, DOSF = 0 310 660 CC (Note 4) V = +5.5V 350 800 CC 0.7 x V + CC Logic 1 Input V (Note 2) V IH V 0.3 CC 0.3 x Logic 0 Input V (Note 2) -0.3 V IL V CC Input Leakage I ECLK = 1, V = 0V to V -0.1 +0.1 FA LI IN CC (SCL, CLKIN/INTA) Output Leakage I ECLK = A1IE = A2IE = 0 -1.0 +1.0 FA O (CLKIN/INTA, SQW/INTB) V R 1.8V, INTCN = 0 -3.0 mA Output Logic 1 CC I OH V = +1.0V (SQW /INTB) OH V R 1.3V, INTCN = 0 -250 FA CC Output Logic 0 V R 1.8V 3.0 mA CC V = +0.4V (SDA, CLKIN/INTA, I OL OL V R 1.3V (Note 5) 250 FA CC SQW/INTB) 2 Maxim Integrated