PCF2127T/2Y

Real Time Clock Overview

The PCF2127T/2Y is a CMOS Real Time Clock (RTC) and calendar integrated with a Temperature Compensated Crystal Oscillator (TCXO) and a 32.768 kHz quartz crystal. It operates within a supply voltage range of 1.8 V to 4.2 V, consuming a typical current of 0.70 µA at 3.3 V. The device provides year, month, day, weekday, hours, minutes, seconds, and leap year correction in Binary Coded Decimal format. It features selectable I²C or SPI interfaces, 512 bytes of battery-backed static RAM, and an operating temperature range from -40 °C to +85 °C.

Real Time Clock Feature Summary

• Integrated TCXO with ±3 ppm accuracy from -30 °C to +80 °C
• Selectable 400 kHz I²C or 6.5 Mbit/s SPI interface
• 512-byte general-purpose static RAM
• Programmable watchdog, alarm, countdown timer, and timestamp functions

Real Time Clock Applications

• Electronic metering for electricity, water, and gas
• Precision timekeeping and accurate process timing
• GPS equipment to reduce time to first fix
• Products requiring long automated unattended operation

Real Time Clock Procurement Notes

Verify the specific suffix /2Y indicates tape and reel packaging on a 13-inch dry pack. Confirm the component status as the datasheet notes potential product longevity variations. Ensure the ordering code matches the SO16 package variant required for the design.

Real Time Clock Selection Notes

Select the PCF2127T/2Y for industrial applications requiring high accuracy without external crystals. The T variant offers ±3 ppm accuracy from -30 °C to +80 °C. Use this model when space constraints prevent discrete crystal mounting or when low power consumption is critical for battery-operated systems.

Real Time Clock Part Context

The PCF2127 family includes the AT variant in an SO20 package and the T variant in an SO16 package. Both share identical functional specifications but differ in pin count and physical dimensions. The PCF2127T/2Y specifically refers to the 16-lead SOIC version delivered in tape and reel format.

Real Time Clock Replacement Considerations

PCF2131TFY is listed as a manufacturer substitute.