Low-Current, SPI-Compatible DS1347 Real-Time Clock General Description Benefits and Features The DS1347 SPI-compatible real-time clock (RTC) con- Completely Manages All Timekeeping Functions tains a real-time clock/calendar and 31 x 8 bits of static RTC Counts Seconds, Minutes, Hours, Day of random-access memory (SRAM). The real-time Week, Date of Month, Month, Year, and Century clock/calendar provides seconds, minutes, hours, day, Leap-Year Compensation date, month, year, and century information. A time/date 31 x 8-Bit SRAM for Scratchpad Data Storage programmable polled ALARM is included in the device. Programmable Time/Date Polled ALARM Function The end-of-the-month date is automatically adjusted for Uses Standard 32.768kHz Watch Crystal months with fewer than 31 days, including corrections Low-Power Operation Extends Battery Life for leap year. The clock operates in either the 24hr or Low Timekeeping Current (400nA at 2V) 12hr format with an AM/PM indicator. The device oper- +2V to +5.5V Wide Operating Voltage Range ates with a supply voltage of +2V to +5.5V, are avail- able in the ultra-small 8-pin TDFN package, and work Standard Serial Port Interfaces with Most over the -40C to +85C industrial temperature range. Microcontrollers SPI (Mode 1 or 3) Interface: 4MHz at 5V, 1MHz Applications at 2V Single-Byte or Multiple-Byte (Burst Mode) Data Point-of-Sale Equipment Transfer for Read or Write of Clock Registers or Intelligent Instruments SRAM Fax Machines 3mm x 3mm x 0.8mm, 8-Pin TDFN Package Battery-Powered Products Minimizes Required Space No External Crystal Bias Resistors or Capacitors Portable Instruments Required Ordering Information OSC C L PART TEMP RANGE PIN-PACKAGE (pF) DS1347T+ -40C to +85C 12.5 8 TDFN-EP* Typical Operating Circuit +Denotes a lead(Pb)-free/RoHS-compliant package. +3.3V *EP = Exposed pad. 0.1F 6 V CC +3.3V 8 X1 DS1347 32.768kHz 1 CRYSTAL SCLK 7 X2 5 c CS 2 DOUT 3 DIN GND 4 19-6007 Rev 5 4/15Low-Current, SPI-Compatible DS1347 Real-Time Clock Absolute Maximum Ratings V to GND..............................................................-0.3V to +6V Junction Temperature .....................................................+150C CC All Other Pins to GND ................................-0.3V to (V + 0.3V) Storage Temperature Range -55C to +125C CC Current into Any Pin..........................................................20mA ESD Protection (All Pins, Human Body Model)................2000V Rate of Rise, V ............................................................100V/s Lead Temperature (soldering, 10s) .................................+300C CC Continuous Power Dissipation (T = +70C) Soldering Temperature (reflow) .......................................+260C A TDFN (derate 24.4mW/C above +70C)...................1.375mW 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 = +2.0V to +5.5V, T = -40C to +85C. Typical values are at V = +3.3V, T = +25C, unless otherwise noted.) (Note 1) CC A CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Operating Voltage V 2 5.5 V CC Range V = +2V 0.1 Active Supply Current CC I mA CC (Note 2) V = +5V 0.25 CC V = +2V 0.35 0.7 CC Timekeeping Supply I V = +3.6V 0.35 0.7 A TK CC Current (Note 3) V = +5V 0.4 0.8 CC SPI DIGITAL INPUTS (SCLK, DIN, CS) V = +2V 1.4 CC Input High Voltage V V IH V = +5V 2.2 CC V = +2V 0.6 CC Input Low Voltage V V IL V = +5V 0.8 CC Input Leakage Current I V = 0 to V -0.1 +0.1 A IL IN CC Input Capacitance C (Note 4) 10 pF IN SPI DIGITAL OUTPUT (DOUT) Output Leakage Current I CS = V -0.1 +0.1 A O IH Output Capacitance C (Note 4) 15 pF OUT V = +2V, I = 1.5mA 0.4 CC SINK Output Low Voltage V V OL V = +5V, I = 4mA 0.4 CC SINK V = +2V, I = -0.4mA 1.8 CC SOURCE Output High Voltage V V OH V = +5V, I = -1mA 4.5 CC SOURCE www.maximintegrated.com Maxim Integrated 2