The PCF2123U/12AA/1,00 is a CMOS 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. An offset register allows fine tuning of the clock.
Feature
- 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 ℃
- 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 combinable 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
- Internal Power-On Reset (POR)
- Open-drain interrupt and clock output pins
- Programmable offset register for frequency adjustment
- Time keeping application
- Battery powered devices
- Metering
- High duration timers
- Daily alarms
- Low standby power applications