PCF2123 Overview
The PCF2123 is a CMOS1 Real-Time Clock (RTC) and calendar optimized for low power applications. Data is transferred serially via a Serial Peripheral Interface (SPI-bus) with a maximum data rate of 6.25 Mbit/s. An alarm and timer function is also available providing the possibility to generate a wake-up signal on an interrupt pin.
PCF2123 Key Features
- Real time clock provides year, month, day, weekday, hours, minutes, and seconds based on a 32.768 kHz quartz crystal
- Low backup current while running: typical 100 nA at VDD = 2.0 V and Tamb = 25 C
- Resolution: seconds to years
- Watchdog functionality
- Freely programmable timer and alarm with interrupt capability
- Clock operating voltage: 1.1 V to 5.5 V
- 3 line SPI-bus with separate, but binable data input and output
- Serial interface at VDD = 1.8 V to 5.5 V
- 1 second or 1 minute interrupt output
- Integrated oscillator load capacitors for CL = 7 pF
PCF2123 Applications
- Real time clock provides year, month, day, weekday, hours, minutes, and seconds based on a 32.768 kHz quartz crystal