X1228S14

Overview

The X1228S14 is a Real-Time Clock (RTC) integrated circuit manufactured by Renesas Electronics Corporation, belonging to the X1228 family. It combines clock/calendar functionality with EEPROM memory and CPU supervision features. The device communicates via an I2C, 2-wire serial interface. It operates within a supply voltage range of 2.7V to 5.5V, while battery backup support extends down to 1.8V. The maximum timekeeping current consumption is specified between 10µA and 20µA at 2.7V to 5V. The component is housed in a 14-SOIC package with a width of 0.154 inches (3.90mm).

Feature Summary

• Integrated Real-Time Clock/Calendar with HH:MM:SS and YY-MM-DD-dd formats.
• Includes non-volatile EEPROM memory for data storage.
• Built-in CPU Supervisor and Watchdog Timer functions.
• Supports Alarm and Leap Year calculations.

Applications

• Industrial control systems requiring precise timekeeping.
• Consumer electronics with calendar and alarm capabilities.
• Data logging devices needing timestamping and storage.
• Embedded systems utilizing I2C communication protocols.

Procurement Notes

The X1228S14 is classified as obsolete and no longer manufactured by Renesas Electronics Corporation. Verification of availability should focus on aftermarket distributors or surplus stock providers. Buyers must confirm the authenticity of existing inventory due to the discontinuation status. Replacement components from other manufacturers may require schematic and firmware adjustments. Compliance with RoHS standards varies by production batch; specific lot verification is recommended before procurement.

Selection Notes

Designers selecting this component should account for its obsolete status and potential long-term supply constraints. The 14-SOIC package requires appropriate PCB footprint planning. Electrical parameters such as the 2.7V minimum operating voltage and 10µA–20µA standby current must align with system power budgets. Alternative solutions from Analog Devices or Maxim Integrated, such as the DS1388 series, are documented as similar replacements but may necessitate design modifications.

Part Context

The X1228S14 is part of the broader X1228 product line, which integrates RTC, EEPROM, and supervisor functions into a single chip. This family was originally developed by Xicor and later acquired by Intersil, then Renesas. The 'S14' suffix typically denotes the 14-pin SOIC package variant. The component serves as a legacy solution for applications requiring combined timing and non-volatile memory management via standard I2C interfaces.

Replacement Considerations

Publicly confirmed substitute part numbers include the DS1388Z-5+ from Analog Devices Inc./Maxim Integrated. Designers should verify pin compatibility and software register mappings when transitioning to alternative RTC ICs. Other potential replacements may exist but require individual datasheet comparison for electrical and functional equivalence.