The NXP PCF85063TP is a CMOS1 real time clock 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. Maximum bus speed is 400 kbit/s. The register address is incremented automatically after each written or read data byte.

Minute and half minute interrupt
Oscillator stop detection function
Internal Power-On Reset (POR)