PCF85263ATT1/AJ

Real Time Clock Overview

The PCF85263ATT1/AJ is a CMOS Real-Time Clock (RTC) and calendar optimized for low power consumption, manufactured by NXP Semiconductors. It features automatic switching to battery backup upon main power loss and supports I2C-bus communication at up to 400 kHz. The device provides year, month, day, weekday, hours, minutes, seconds, and 100th seconds based on a 32.768 kHz quartz crystal. Operating voltage ranges from 0.9 V to 5.5 V with typical current consumption of 0.28 μA at 3.0 V. It includes two independent alarms, three timestamp registers, a watchdog timer, and programmable clock outputs.

Real Time Clock Feature Summary

• Automatic battery switch-over circuit for continuous operation during power loss
• Two independent alarms and three timestamp registers triggered by events or battery switch
• Stop-watch mode capable of counting elapsed time from 100th seconds to 999,999 hours
• Programmable clock output frequencies including 32.768 kHz, 16.384 kHz, 8.192 kHz, 4.096 kHz, 2.048 kHz, 1.024 kHz, and 1 Hz

Real Time Clock Applications

• Printers and copiers
• Electronic metering devices
• Digital cameras
• White goods
• Data loggers

Real Time Clock Procurement Notes

Verify the ordering suffix 'AJ' corresponds to the TSSOP10 package variant as specified in the official NXP data sheet. Confirm that the component meets the required temperature range of -40 °C to +85 °C. Ensure compatibility with the 400 kHz I2C interface speed requirements of the target system design.

Real Time Clock Selection Notes

Select this model when a TSSOP10 package is required instead of the standard TSSOP8. The ATT1 variant offers additional pins for configurable clock output and timestamp input compared to the 8-lead versions. Verify that the application utilizes the extra GPIO capabilities provided by the 10-lead configuration.

Real Time Clock Part Context

This part belongs to the PCF85263A family of tiny RTCs. The ATT1 designation specifically identifies the TSSOP10 plastic thin shrink small outline package version. It shares core functionality with other variants like AT/AJ (SO8) and ATT/AJ (TSSOP8) but differs in physical footprint and pin availability.

Real Time Clock Replacement Considerations

PCF85263ATT1/AZ is listed as a drop-in replacement for discontinued PCF85263ATT1/AJ variants according to PCN 202104008A. Both use Static Shielding Bag (SSB) packing methods.