ISL12027AIB27Z-T

Real Time Clock Overview

The ISL12027AIB27Z-T is a low-power real-time clock/calendar with integrated 512x8-bit EEPROM, oscillator compensation, and CPU supervisor functions. It operates on an I2C bus interface at up to 400kHz. The device tracks time in hours, minutes, and seconds, and maintains calendar data through 2099 with automatic leap year correction. It features two non-volatile alarms, intelligent battery backup switching between VDD and VBAT, and a watchdog timer. The component uses an external 32.768kHz crystal and includes on-chip frequency adjustment settings of ±30ppm. Power supply ranges from 2.7V to 5.5V for VDD and 1.8V to 5.5V for VBAT.

Real Time Clock Feature Summary

• Integrated 512x8-bit EEPROM with 16-byte page write mode and BlockLock protection
• Automatic battery backup switching with Standard Mode setting (BSW=0)
• On-chip oscillator compensation with 64-position digital trim and ±30ppm adjustment
• Two non-volatile alarms with periodic interrupt capability

Real Time Clock Applications

• Utility meters
• HVAC equipment
• Network routers, hubs, switches, and bridges
• POS equipment
• Office automation devices

Real Time Clock Procurement Notes

Verify the obsolete status of this part number before procurement planning. Confirm that the -T suffix indicates tape and reel packaging as per Intersil/Renesas ordering guidelines. Ensure compatibility with existing BOMs given the product lifecycle status.

Real Time Clock Selection Notes

Select the ISL12027A variant specifically if the application requires VBAT > VDD operation, as it utilizes the Standard Mode Setting unlike the legacy ISL12027. Verify the required reset voltage threshold matches the IB27 designation (2.63V). Ensure the package type corresponds to the SOIC-8 form factor indicated by the 'I' code.

Real Time Clock Part Context

This component belongs to the ISL12027 family of real-time clocks manufactured by Renesas Electronics (formerly Intersil). The specific suffix IB27 denotes the 8-lead SOIC package and a 2.63V reset threshold. The 'A' variant distinguishes it from the original ISL12027 by using different power control settings suitable for specific backup scenarios.

Real Time Clock Replacement Considerations

The datasheet explicitly states this is an obsolete product with no recommended replacement. Contact technical support for alternatives. Cross-model generic features should not be assumed; verify electrical parameters against potential substitutes.