The PCF8563T/5,518 is a Real Time Clock Binary I2C 1-5V with low power consumption manufactured by NXP. It is a low-power, keep-alive Real-Time Clock (RTC) and calendar for I2C bus applications such as consumer electronics, industrial process control, or medical instrumentation. It includes an oscillator, power management circuitry, a timer, a calendar, and an array of control registers. The device provides accurate time-keeping, date, and time, and alarm functions in a small circuit board footprint, and is optimized for low power consumption. It also offers an I2C interface and supports one-wire and two-wire communication. The device is available in 800 kHz and 400 kHz versions and is available in a 14-pin dual in-line package.