X1228S14Z

Overview

The X1228S14Z is a Real-Time Clock (RTC) integrated circuit manufactured by Renesas Electronics Corporation. It integrates a clock/calendar, CPU supervisor, and 512-byte EEPROM within a single device. The component communicates via an I²C, 2-wire serial interface. It operates with a supply voltage range of 2.7V to 5.5V and supports battery backup voltages from 1.8V to 5.5V. The timekeeping current consumption is specified between 10µA and 20µA at 2.7V to 5V. The device is housed in a 14-SOIC package with a width of 0.154 inches (3.90mm).

Feature Summary

• Integrated RTC with calendar functionality supporting HH:MM:SS time format and YY-MM-DD-dd date format.
• Includes 512 bytes (64 x 8) of EEPROM for data storage.
• Features built-in CPU supervisor and watchdog timer capabilities.
• Supports alarm functions and leap year compensation.

Applications

• Industrial control systems requiring precise timekeeping.
• Data logging equipment needing non-volatile memory retention.
• Consumer electronics with real-time clock requirements.

Procurement Notes

The X1228S14Z is classified as obsolete and no longer manufactured by Renesas Electronics Corporation. Verification of availability should focus on surplus distributors or secondary markets. Designers must confirm the RoHS status of available stock, as earlier production runs may not comply with current environmental regulations. Replacement components should be evaluated for pin compatibility and functional equivalence before procurement.

Selection Notes

Select this component only if legacy compatibility with the X1228 family is required. Verify that the 14-SOIC package dimensions fit the target PCB layout. Ensure the application can accommodate the I²C interface timing specifications. Consider the operating temperature range of -40°C to 85°C against environmental conditions. Evaluate alternative modern RTCs if new design constraints allow for updated packaging or interfaces.

Part Context

The X1228S14Z belongs to the X1228 series, which combines RTC, EEPROM, and supervisor functions. This series was originally developed by Intersil and later acquired by Renesas. The 'S14' suffix denotes the 14-pin SOIC package variant. Similar parts in the family include the X1228S14I and X1228V14IZ, differing primarily in package type or temperature grade.

Replacement Considerations

Publicly documented substitutes include the DS1388Z-5+ from Analog Devices Inc./Maxim Integrated and the BU9873NUX-TTR from Rohm Semiconductor. These alternatives offer similar RTC and EEPROM functionalities but require verification of pinout compatibility and software register mapping differences.