The PCF85063TP/1Z is a tiny Real Time Clock (RTC)/calendar manufactured by NXP (formerly Philips Semiconductor). It features an I2C-interfaced standalone timekeeper with 64 bytes of battery buffered SRAM and a programmable I2C slave address, making it ideal for use in low-power applications. It integrates a 32-bit timer, 31-bit programmable counter, enough for a full day, and a century register, which allows one to set the year to 20xx or 21xx. In addition, it has an end-of-month (EOM) indicator which flags when extra day adjustment is required. It also has power fail detection, programmable alarm, and interrupt logic. The highly integrated device requires a tiny amount of space due to its small form factor and is RoHS Compliant.