The PCF85063A is a CMOS1 Real-Time Clock (RTC) and calendar optimized for low power consumption. An offset register allows fine-tuning of the clock. All addresses and data are transferred serially via the two-line bidirectional I2C bus. The maximum data rate is 400 kbit/s. The registered address is incremented automatically after each written or read
data byte.

Note: For more technical details go through the Datasheet in the attachment section

Features:

1. Provides year, month, day, weekday, hours, minutes, and seconds based on a32.768 kHz quartz crystal
2. Clock operating voltage: 0.9 V to 5.5 V
3. Low current; typical 0.22 mA at VDD = 3.3 V and Tamb = 25 C
4. 400 kHz two-line I2C-bus interface (at VDD = 1.8 V to 5.5 V)
5. Programmable clock output for peripheral devices (32.768 kHz, 16.384 kHz,
6. 8.192 kHz, 4.096 kHz, 2.048 kHz, 1.024 kHz, and 1 Hz)
7. Selectable integrated oscillator load capacitors for CL = 7 pF or CL = 12.5 pF
8. Alarm function
9. Countdown timer
10. Minute and minute interrupt
11. Oscillator stop detection function
12. Internal Power-On Reset (POR)
13. Programmable offset register for frequency adjustment

Package Includes:

1 x PCF85063AT/AAZ NXP RTC, Date Time Format (YY-MM-DD-dd, HH:MM:SS), I2C, 0.9V to 5.5V Supply, SOIC-8