PCF2129A

PCF2129A Integrated RTC, TCXO and quartz crystal Rev. 01 — 13 January 2010 www.DataSheet4U.com Product data sheet 1. General description The PCF2129A is a CMOS1 real time clock and calendar with an integrated Temperature Compensated Crystal (Xtal) Oscillator (TCXO) and a 32.768 kHz quartz crystal optimized for very high accuracy and very low power consumption. The PCF2129A has a selectable I2C-bus or SPI-bus, a backup battery switch-over circuit, a programmable watchdog function, a timestamp function, and many other features. 2. Features „ „ „ „ „ Temperature Compensated Crystal Oscillator (TCXO) with integrated capacitors Accuracy: ±3 ppm from −15 °C to +60 °C Integration of a 32.768 kHz quartz crystal and oscillator in the same package Provides year, month, day, weekday, hours, minutes, and seconds Timestamp function ‹ with interrupt capability ‹ detection of two different events on one multilevel input pin (e.g. for tamper detection) Two line bidirectional 1 MHz Fast-mode Plus (Fm+) I2C-bus interface (IOL = 20 mA at pin SDA) 3 line SPI-bus with separate data input and output (maximum speed 6.5 Mbit/s) Battery backup input pin and switch-over circuitry Battery backed output voltage pin Battery low detection function Extra power fail detection function with input and output pins Power-On Reset Override (PORO) Oscillator stop detection function Interrupt output (open-drain) Programmable 1 second or 1 minute interrupt Programmable watchdog timer with interrupt and reset ca...