ISL12027IBAZ

Real Time Clock Overview

The ISL12027IBAZ is an obsolete Real Time Clock/Calendar integrated circuit manufactured by Renesas Electronics Corporation (formerly Intersil). It features an I2C interface, 512x8-bit EEPROM, and intelligent battery backup switching. The device operates within a supply voltage range of 2.7V to 5.5V on VDD and 1.8V to 5.5V on VBAT. Key specifications include a battery supply current of 800nA at 1.8V, a low-voltage reset threshold of 4.64V, and operation across a temperature range of -40°C to +85°C. It utilizes an external 32.768kHz crystal for timing.

Real Time Clock Feature Summary

• I2C-bus Interface supporting up to 400kHz data transfer rate
• On-Chip Oscillator Compensation with 64-position digitally controlled trim capacitor
• Two Non-Volatile Alarms with repeat mode for periodic interrupts
• Integrated CPU Supervisor including Watchdog Timer and Low Voltage Reset

Real Time Clock Applications

• Utility Meters
• HVAC Equipment
• Network Routers, Hubs, Switches, Bridges
• POS Equipment
• Test Meters/Fixtures

Real Time Clock Procurement Notes

The ISL12027IBAZ is classified as an obsolete product with no recommended replacement available from the manufacturer. Verification of component authenticity and physical condition is critical when sourcing from secondary markets. Designers should assess long-term availability risks and consider redesigning systems if this component is required for new production.

Real Time Clock Selection Notes

Selection requires matching the specific Low Voltage Reset (LVR) threshold; the 'BAZ' suffix indicates a 4.64V trip point. Ensure the application supports the Legacy Mode setting used by the ISL12027, distinct from the Standard Mode of the ISL12027A variant. Verify that the system design accommodates the 8 Ld SOIC package dimensions and the requirement for an external 32.768kHz quartz crystal.

Real Time Clock Part Context

This part belongs to the ISL12027 family of real-time clocks, which integrates clock/calendar functions with non-volatile memory. The ISL12027IBAZ specifically denotes the 8-lead SOIC package variant with a 4.64V reset threshold. It differs from the ISL12027A series in its power control settings and battery switching behavior.

Real Time Clock Replacement Considerations

The datasheet explicitly states there is no recommended replacement for this obsolete product. Engineers must contact technical support or evaluate alternative RTC solutions with compatible pinouts and electrical characteristics.