●Overview
●The PCF2127 is a CMOS Real Time Clock (RTC) 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 PCF2127 has 512 bytes of general-purpose static RAM, a selectable I²C-bus or SPI-bus, a backup battery switch-over circuit, a programmable watchdog function, a timestamp function, and many other features.
●MoreLess
●## Features
● UL Recognized Component
● Operating temperature range from -40 °C to +85 °C
● Temperature Compensated Crystal Oscillator (TCXO) with integrated capacitors
● Typical accuracy:
● PCF2127AT: ±3 ppm from -15 °C to +60 °C
● PCF2127T: ±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
● 512 bytes of general-purpose static RAM
● Timestamp function:
● with interrupt capability
● detection of two different events on one multilevel input pin (for example, for tamper detection)
● Two line bidirectional 400 kHz Fast-mode I²C-bus interface
● 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
● 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
● Programmable alarm function with interrupt capability
● Programmable square wave output pin
● Programmable countdown timer with interrupt
● Clock operating voltage: 1.8 V to 4.2 V
● Low supply current: typical 0.70 μA at VDD = 3.3 V
●## Target Applications
● Electronic metering for electricity, water, and gas
● Precision timekeeping
● Access to accurate time of the day
● GPS equipment to reduce time to first fix
● Applications that require an accurate process timing
● Products with long automated unattended operation time
●## Features
