PCF2129 Datasheet (PDF) Download
NXP Semiconductors
PCF2129

Description

The PCF2129 is a CMOS1 Real Time Clock (RTC) and calendar with an integrated Temperature pensated Crystal (Xtal) Oscillator (TCXO) and a 32.768 kHz quartz crystal optimized for very high accuracy and very low power consumption. The PCF2129 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.

Key Features

  • UL Recognized ponent (PCF2129AT and PCF2129T)
  • Operating temperature range from -40 °C to +85 °C
  • Typical accuracy: – PCF2129AT: ±3 ppm from -15 °C to +60 °C – PCF2129T: ±3 ppm from -30 °C to +80 °C
  • Integration of a 32.768 kHz quartz crystal and oscillator in the same package
  • Provides year, month, day, weekday, hours, minutes, seconds, and leap year correction
  • Two line bidirectional 400 kHz Fast-mode I2C-bus interface
  • Three 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
  • Battery low detection function