 Built in frequency adjusted 32.768 kHz crystal unit and DTCXO
 Interface Type : 3 wire / 4 wire SPI-Bus
Current consumption : 240 nA / 3 V (Typ.)
Auto power switching function : Automatically switches to backup power supply
by monitoring the VDD / VBAT voltage
Time stamp function : Maximum 32 time stamps
Interrupt output : Wake up every hour or every minute or every second
Alarm interruption : Day, date, hour, minute, second
Auto repeat wakeup timer interruption
Self-monitoring interruption : Crystal oscillation stop, VBAT low, VDD low