PCF2123 Datasheet PDF

●Overview

●The PCF2123 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.

●MoreLess

●## 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 ℃

● 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

●## Target Applications

● Time keeping application

● Battery powered devices

● Metering

● High duration timers

● Daily alarms

● Low standby power applications

●## Features