Part Number : DS1340
Function : 2-Wire RTC with trickle charger
Package : SOP 8 Pin, SO 8 Pin Type
Maker : Dallas Semiconductor , Maxim Integrated
Pinouts : 
General Description :
The DS1340 is a real-time clock (RTC)/calendar that is pin compatible and functionally equivalent to the ST M41T00, including the software clock calibration. The device additionally provides trickle-charge capability on the VBACKUPpin, a lower timekeeping voltage, and an oscillator STOP flag. Block access of the register map is identical to the ST device. Two additional regis
ters, which are accessed individually, are required for the trickle charger and flag. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. A built-in power-sense circuit detects power failures and automatically switches to the back up supply. Reads and writes are inhibited while the clock continues to run. The device is programmed serially through an I2C bidirectional bus.
Features
1. Enhanced Second Source for the ST M41T00
2. Available in a Surface-Mount Package with an Integrated Crystal (DS1340C)
3. Fast (400kHz) I2C Interface
4. Software Clock Calibration
5. RTC Counts Seconds, Minutes, Hours, Day, Date, Month, and Year
6. Automatic Power-Fail Detect and Switch Circuitry
7. Trickle-Charge Capability
8. Low Timekeeping Voltage Down to 1.3V
9. Three Operating Voltage Ranges (1.8V, 3V, and 3.3V)
10. Oscillator Stop Flag
Datasheet PDF Download : 
Others datasheet of same file :
DS-1340, DS1340C-18#, DS1340C-3#,
DS1340C-33#, DS1340U-18+
