ISL12028IB30AZ

Real Time Clock Overview

The ISL12028IB30AZ is a low-power real-time clock/calendar integrated circuit manufactured by Renesas Electronics. It features an I2C bus interface with a maximum data transfer rate of 400kHz and includes 512x8-bit EEPROM for non-volatile data storage. The device operates within a supply voltage range of 2.7V to 5.5V on VDD and supports backup power from 1.8V to 5.5V on the VBAT pin. It provides automatic battery backup switching, two programmable alarms, and CPU supervisor functions including a watchdog timer and power-on reset. The component is housed in a 14-lead SOIC package and is rated for operation between -40°C and +85°C.

Real Time Clock Feature Summary

• Integrated 512x8-bit EEPROM with BlockLock protection and >2,000,000 cycle endurance
• Dual alarms with periodic interrupt capability and hardware interrupt output
• On-chip oscillator compensation with 64-position digital trim for frequency adjustment
• CPU Supervisor functions including Power-On Reset, Low Voltage Sense, and Watchdog Timer

Real Time Clock Applications

• Utility Meters
• HVAC Equipment
• Network Routers, Hubs, Switches, Bridges
• POS Equipment
• Computer Products

Real Time Clock Procurement Notes

Verify the specific ordering suffix 'B30' against current manufacturer documentation to confirm the VRESET threshold level of approximately 3.09V. Confirm package availability as this part number may be subject to limited supply or end-of-life status depending on the manufacturing date code. Ensure compatibility with the legacy mode power control settings associated with the standard ISL12028 variant rather than the ISL12028A standard mode.

Real Time Clock Selection Notes

Select this component when a fixed low-voltage reset threshold near 3.0V is required for system supervision. The ISL12028IB30AZ utilizes Legacy Mode power control settings, which differ from the ISL12028A Standard Mode; ensure the application design accounts for these specific power control requirements. Verify that the external crystal matches the internal compensation network specifications for optimal accuracy across the operating temperature range.

Real Time Clock Part Context

This part belongs to the ISL12028 family of real-time clocks, distinct from the ISL12028A series which employs different power control settings. The 'IB' designation indicates a 14-lead SOIC package, while the '30' suffix specifies the Low Voltage Reset threshold. This model represents a specific configuration within the broader Intersil/Renesas RTC portfolio designed for industrial and commercial applications requiring reliable timekeeping and data retention.

Real Time Clock Replacement Considerations

The datasheet explicitly states this is an obsolete product with no recommended replacement. Contact Technical Support for potential alternatives.