2 I C RTC with Trickle Charger DS1340 General Description Benefits and Features The DS1340 is a real-time clock (RTC)/calendar that is Enhanced Second Source for the ST M41T00 pin compatible and functionally equivalent to the ST Completely Manages All Timekeeping Functions M41T00, including the software clock calibration. The RTC Counts Seconds, Minutes, Hours, Day, Date, device additionally provides trickle-charge capability Month, and Year on the V pin, a lower timekeeping voltage, and BACKUP Software Clock Calibration an oscillator STOP flag. Block access of the register Oscillator Stop Flag map is identical to the ST device. Two additional regis- Low-Power Operation Extends Battery Backup Run ters, which are accessed individually, are required for Time the trickle charger and flag. The clock/calendar pro- Low Timekeeping Voltage Down to 1.3V vides seconds, minutes, hours, day, date, month, and Automatic Power-Fail Detect and Switch Circuitry year information. A built-in power-sense circuit detects power failures and automatically switches to the back- Trickle-Charge Capability up supply. Reads and writes are inhibited while the Three Operating Voltage Ranges (1.8V, 3V, and 3.3V) clock continues to run. The device is programmed seri- Supports Systems Using Legacy and Modern Power 2 ally through an I C bidirectional bus. Buses Surface-Mount Package with an Integrated Crystal (DS1340C) Saves Additional Space and Simplifies Applications Design Portable Instruments Simple Serial Port Interfaces with Most Microcontrollers 2 Fast (400kHz) I C Interface Point-of-Sale Equipment 8-Pin SOP or SO Package Minimizes Required Medical Equipment Space Telecommunications Underwriters Laboratories (UL ) Recognized Ordering Information Typical Operating Circuit PIN- PART TEMP RANGE TOP MARK PACKAGE V 8 SO V CC CC DS1340Z-18+ -40C to +85C D1340-18 (0.150in) CRYSTAL 8 SO V CC DS1340Z-3+ -40C to +85C DS1340-3 R R C1 PU PU (0.150in) 12 8 X1 X2 V CC 8 SO 6 7 DS1340Z-33+ -40C to +85C D134033 SCL FT/OUT (0.150in) DS1340U-18+ -40C to +85C 8 SOP 1340 -18 CPU DS1340 DS1340U-3+ -40C to +85C 8 SOP 1340 -3 3 5 SDA V BACKUP DS1340U-33+ -40C to +85C 8 SOP 1340 -33 GND DS1340C-18 -40C to +85C 16 SO DS1340C-18 4 R = t / C PU R B DS1340C-3 -40C to +85C 16 SO DS1340C-3 DS1340C-33 -40C to +85C 16 SO DS1340C-33 +Denotes a lead(Pb)-free/RoHS-compliant package. Denotes a RoHS-compliant device that may include lead(Pb) that is exempt under RoHS requirements. The lead finish is Pin Configurations appear at end of data sheet. JESD97 category e3, and is compatible with both lead-based and lead-free soldering processes. A anywhere on the top mark denotes a lead(Pb)-free device. UL is a registered trademark of Underwriters Laboratories Inc. A denotes a RoHS-compliant device. 19-5578 Rev 9 4/152 I C RTC with Trickle Charger DS1340 Absolute Maximum Ratings Voltage Range on V or V Pins Operating Temperature Range ...........................-40C to +85C CC BACKUP Relative to Ground.............................................-0.3V to +6.0V Storage Temperature Range .............................-55C to +125C Voltage Range on SDA, SCL, and FT/OUT Lead Temperature (soldering, 10s) .................................+260C Relative to Ground..................................-0.3V to (V + 0.3V) Soldering Temperature (reflow) .......................................+260C CC 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 DC Operating Conditions (V = V to V , T = -40C to +85C, unless otherwise noted. Typical values are at V = 3.3V, T = +25C, unless CC CC MIN CC MAX A CC A otherwise noted.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DS1340-18 1.71 1.8 5.5 Supply Voltage (Note 2) V V DS1340-3 2.7 3.0 5.5 CC DS1340-33 2.97 3.3 5.5 Input Logic 1 (SDA, SCL) V (Note 2) 0.7 x V V + 0.3 V IH CC CC Input Logic 0 (SDA, SCL) V (Note 2) -0.3 +0.3 x V V IL CC Supply Voltage, Pullup V (Note 2) 5.5 V PU (FT/OUT, SDA, SCL), V = 0V CC DS1340-18 1.3 3.7 Backup Supply Voltage (Note 2) V DS1340-3 1.3 3.7 V BACKUP DS1340-33 1.3 5.5 R1 (Notes 3, 4) 250 Trickle-Charge Current-Limiting R2 (Note 5) 2000 Resistors R3 (Note 6) 4000 DS1340-18 1.51 1.6 1.71 Power-Fail Voltage (Note 2) V V DS1340-3 2.45 2.6 2.7 PF DS1340-33 2.70 2.88 2.97 Input Leakage (SCL, CLK) I -1 +1 A LI I/O Leakage (SDA, FT/OUT) I -1 +1 A LO V > 2V V = 0.4V 3.0 CC OL SDA Logic 0 Output I mA OLSDA 1.7V < V < 2V V = 0.2 x V 3.0 CC OL CC V > 2V V = 0.4V 3.0 CC OL mA FT/OUT Logic 0 Output I 1.7V < V < 2V V = 0.2 x V 3.0 OLSQW CC OL CC 1.3V < V < 1.7V V = 0.2x V 250 A CC OL CC DS1340-18 V = 1.89V 72 150 CC Active Supply Current (Note 7) I A CCA DS1340-3 V = 3.3V 108 200 CC DS1340-33 V = 5.5V 192 300 CC DS1340-18 V = 1.89V 60 100 CC Standby Current (Note 8) I A DS1340-3 V = 3.3V 81 125 CCS CC DS1340-33 V = 5.5V 100 150 CC V Leakage Current I V = 3.7V 100 nA BACKUP BACKUPLKG BACKUP www.maximintegrated.com Maxim Integrated 2