X1227S8I-4.5A

Overview

The X1227S8I-4.5A is a Real Time Clock (RTC) integrated circuit manufactured by Renesas Electronics Corporation, designed for precise timekeeping and calendar functions in electronic systems. It features an I²C, 2-Wire Serial interface for communication with host processors. The device operates within a supply voltage range of 4.5V to 5.5V for main power, while supporting a battery backup input ranging from 1.8V to 5.5V to maintain time during power loss. It is housed in an 8-SOIC package with a width of 3.90mm. The IC includes a watchdog timer and CPU supervisor capabilities, ensuring system reliability. Current consumption for timekeeping is specified between 10µA and 20µA at voltages between 2.7V and 5V.

Feature Summary

• Integrates real-time clock and calendar functionality with leap year compensation
• Includes built-in watchdog timer and CPU supervisor for system protection
• Supports low-power operation with battery backup for continuous timekeeping
• Utilizes standard I²C 2-Wire Serial interface for efficient data exchange

Applications

• Embedded systems requiring accurate date and time tracking
• Industrial control units needing watchdog timer supervision
• Data logging devices with battery-backed memory requirements
• Consumer electronics utilizing CPU supervisor features

Procurement Notes

Verify the specific suffix '4.5A' corresponds to the required operating voltage range of 4.5V to 5.5V when sourcing replacements. Confirm that the 8-SOIC package dimensions match the PCB footprint design. Ensure compatibility with the I²C bus speed requirements of the target application. Check for genuine Renesas manufacturing origin to guarantee parameter accuracy and long-term reliability in critical timekeeping roles.

Selection Notes

Select this component when a dedicated RTC with integrated system management features is required. The 4.5V minimum supply voltage dictates suitability for 5V logic systems rather than low-voltage applications. Consider the 8-SOIC package size constraints against available board space. Evaluate the need for both watchdog and supervisor functions to simplify bill of materials compared to discrete solutions.

Part Context

This part belongs to the X1227 series of Real Time Clocks from Renesas, which are designed for high accuracy and low power consumption. The series typically offers various package options and voltage variants to suit different embedded applications. The X1227S8I-4.5A specifically targets 5V systems requiring robust timekeeping alongside basic system monitoring capabilities through its integrated supervisor and watchdog timers.

Replacement Considerations

Compatible substitutes include other parts from the X1227 family such as the X1227S8I-2.7, provided the voltage requirements align with the application design. Verify pinout compatibility and interface standards before substitution.