X1228S14-2.7A

Overview

The X1228S14-2.7A is an I2C Real-Time Clock (RTC) and calendar IC from the Renesas X1228 family, housed in a 14-SOIC package. It tracks hours, minutes, seconds, day of week, date, month, and year with automatic leap year correction through 2099. The device operates on a main supply of 2.7V to 5.5V and supports battery backup from 1.8V to 5.5V. Key features include two alarms, a watchdog timer, power-fail detection, and oscillator compensation. It consumes 10µA to 20µA during timekeeping at 2.7V–5V and interfaces via I2C at up to 400kHz.

Feature Summary

• I2C interface with 400kHz data transfer rate
• Automatic leap year correction through 2099
• On-chip oscillator compensation for accuracy
• Power-fail detection and automatic battery backup switching

Applications

• Utility meters requiring precise timekeeping
• HVAC equipment with scheduling needs
• Industrial systems needing watchdog timer functionality

Procurement Notes

Verify component authenticity due to potential obsolete status or cross-manufacturer origins within the X1228 lineage. Confirm RoHS compliance as earlier variants may not meet current standards. Check for pin-compatible alternatives if lead times are critical, as availability varies by distributor.

Selection Notes

Select this part for applications requiring I2C connectivity and low-power RTC functionality with integrated EEPROM-like SRAM capabilities. Ensure voltage levels match the 2.7V–5.5V VCC and 1.8V–5.5V VBAT ranges. Consider the 14-SOIC package constraints for PCB layout.

Part Context

Part of the X1228 series, which shares pinouts with ST M41Txx and Maxim DS13xx devices. This facilitates drop-in replacements in existing designs using those legacy components. The series emphasizes low power consumption and robust battery backup mechanisms.

Replacement Considerations

Pin-compatible substitutes include ST M41Txx and Maxim DS13xx series RTCs. Verify electrical specifications such as battery current and alarm configurations before substitution.