X1228S14Z-4.5A

Overview

The X1228S14Z-4.5A is a discontinued Real-Time Clock (RTC) integrated circuit manufactured by Renesas Electronics Corporation. It features an I2C interface for clock/calendar functionality, supporting time formats of HH:MM:SS and date formats of YY-MM-DD-dd. The device operates within a supply voltage range of 2.7V to 5.5V and includes battery backup support from 1.8V to 5.5V. Key electrical characteristics include a maximum current consumption of 10µA to 20µA at 2.7V to 5V. It is housed in a 14-SOIC package with a width of 3.90mm.

Feature Summary

• I2C Interface: Supports 2-wire serial communication with a data transfer rate up to 400kHz.
• Calendar Functionality: Tracks hours, minutes, seconds, day of the week, day, month, and year with automatic leap year correction through 2099.
• Battery Backup: Intelligent switching between main power and battery/super capacitor sources to maintain timekeeping during power failures.
• Alarm and Interrupts: Features a single alarm settable to second, minute, hour, day of week, day, or month, with event or pulse interrupt modes.

Applications

• Industrial equipment requiring precise timekeeping and calendar functions.
• Power management systems needing power failure detection and logging.
• Consumer electronics utilizing low-power real-time clocking via I2C.

Procurement Notes

This component is officially obsolete and no longer manufactured by Renesas Electronics Corporation. Verification of availability should focus on distributor stock levels for remaining inventory rather than direct manufacturer orders. Buyers must confirm RoHS compliance status, as the specific part may not meet current environmental regulations. Replacement sourcing requires evaluating equivalent parts from other manufacturers, such as Analog Devices/Maxim Integrated, ensuring pin compatibility and functional equivalence.

Selection Notes

Designers selecting this RTC should verify the 14-SOIC package dimensions against PCB layout constraints. The operating temperature range spans -40°C to 85°C, suitable for industrial environments. Ensure the system design accommodates the 2.7V to 5.5V VCC supply and the 1.8V to 5.5V battery backup range. The I2C bus speed capability of 400kHz should be matched with appropriate pull-up resistors for reliable communication.

Part Context

The X1228 series represents Renesas' line of I2C-based real-time clocks with EEPROM capabilities. The X1228S14Z-4.5A specifically denotes the SOIC package variant with specific suffix codes indicating packaging or testing variations. This part shares architectural similarities with Maxim DS13xx devices, facilitating drop-in replacements in legacy designs that utilized those components.

Replacement Considerations

Analog Devices Inc./Maxim Integrated offers the DS1388Z-5+ as a similar replacement option. Designers should verify pinout compatibility and register mapping differences before substituting the obsolete X1228S14Z-4.5A with alternative RTC ICs from other vendors.