PCF2127AT/2Y

Real Time Clock Overview

The PCF2127AT/2Y is a CMOS Real Time Clock (RTC) and calendar featuring an integrated Temperature Compensated Crystal Oscillator (TCXO) and a 32.768 kHz quartz crystal within the same package. It provides high accuracy with typical performance of ±3 ppm from -15°C to +60°C. The device includes 512 bytes of battery-backed static RAM, selectable I²C or SPI interfaces, and supports industrial operating temperatures from -40°C to +85°C. Powered by 1.8 V to 4.2 V, it consumes a typical supply current of 0.70 µA at 3.3 V.

Real Time Clock Feature Summary

• Integrated TCXO and 32.768 kHz quartz crystal for high precision timing
• Selectable 400 kHz Fast-mode I²C or 6.5 Mbit/s 3-line SPI interface
• 512-byte general-purpose static RAM with battery backup
• Programmable timestamp function with interrupt capability for tamper detection

Real Time Clock Applications

• Electronic metering for electricity, water, and gas
• GPS equipment to reduce time to first fix
• Precision timekeeping systems
• Long automated unattended operation products

Real Time Clock Procurement Notes

Verify the specific suffix '2Y' corresponds to tape and reel packaging in dry pack format as per ordering information. Confirm the AT variant designation ensures the specified accuracy range of ±3 ppm from -15°C to +60°C. Check for UL Recognized Component status if required for end-product certification. Ensure compatibility with the SO20 plastic small outline package dimensions.

Real Time Clock Selection Notes

Select this component when high accuracy is required without external crystals. The AT version offers tighter tolerance (-15°C to +60°C) compared to the T version. Use the SPI interface for higher speed data transfer up to 6.5 Mbit/s, or I²C for standard bus connectivity. Ensure the application voltage falls within the 1.8 V to 4.2 V range to maintain low power consumption specifications.

Real Time Clock Part Context

The PCF2127 series is designed for industrial applications requiring precise timekeeping. The PCF2127AT variant specifically targets environments with moderate temperature variations, offering superior stability compared to standard RTCs. It integrates calibration parameters into OTP cells, reducing system complexity by eliminating external compensation components.

Real Time Clock Replacement Considerations

PCF2131TFY is listed as a manufacturer substitute. Verify pinout compatibility between the SO20 package of the PCF2127AT and the target package of the replacement part. Confirm that the substitute maintains the required accuracy specifications and interface speeds for the specific application design.