The PCF8523T/1,118 is a Real-Time Clock and calendar optimized for low power consumption. Data is transferred serially via the I2C-bus with a maximum data rate of 1000kbps. Alarm and timer functions are available with the possibility to generate a wake-up signal on an interrupt pin. An offset register allows fine-tuning of the clock. This has a backup battery switch-over circuit, which detects power failures and automatically switches to the battery supply when a power failure occurs.
Battery backup input pin and switch-over circuit
Freely programmable timer and alarm with interrupt capability
Internal power-on reset
Open-drain interrupt or clock output pins
Programmable offset register for frequency adjustment
