PCF2129A Datasheet, PDF (1/68 Pages) NXP Semiconductors – Integrated RTC, TCXO and quartz crystal

PCF2129A
Integrated RTC, TCXO and quartz crystal
Rev. 01 — 13 January 2010
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 (I_OL = 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 capability
„ Programmable alarm function with interrupt capability
„ Programmable square wave open-drain output pin
„ Clock operating voltage: 1.2 V to 4.2 V
„ Low supply current: typical 0.65 μA at V_DD = 3.0 V and T_amb = 25 °C
„ Automatic leap year correction
1. The definition of the abbreviations and acronyms used in this data sheet can be found in Section 17.