General description
The PCF8563 is a CMOS real-time clock/calendar optimized for low power
consumption. A programmable clock output, interrupt output and voltage-low detector
are also provided. All address and data are transferred serially via a two-line
bidirectional I2C-bus. Maximum bus speed is 400 kbits/s. The built-in word address
register is incremented automatically after each written or read data byte.

Features
■ Provides year, month, day, weekday, hours, minutes and seconds based on 32.768 kHz quartz crystal
■ Century flag
■ Wide operating supply voltage range: 1.0 to 5.5 V
■ Low back-up current; typical 0.25 µA at VDD = 3.0 V and Tamb = 25 °C
■ 400 kHz two-wire I2C-bus interface (at VDD = 1.8 to 5.5 V)
■ Programmable clock output for peripheral devices: 32.768 kHz, 1024 Hz, 32 Hz and 1 Hz
■ Alarm and timer functions
■ Voltage-low detector
■ Integrated oscillator capacitor
■ Internal power-on reset
■ I2C-bus slave address: read A3H; write A2H
■ Open drain interrupt pin.

Applications
■ Mobile telephones
■ Portable instruments
■ Fax machines
■ Battery powered products.