ISL12028IB30AZ-T

Real Time Clock Overview

The ISL12028IB30AZ-T 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 VBAT. Key specifications include a battery supply current of 800nA at 1.8V, an operating temperature range of -40°C to +85°C, and a VRESET threshold of 3.09V. It utilizes an external 32.768kHz crystal and provides automatic leap year correction through the year 2099.

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 selectable frequency outputs (1Hz, 4096Hz, 32.768kHz).
• CPU supervisor functions including Power-On Reset, Low Voltage Sense, and Watchdog Timer (0.25s, 0.75s, 1.75s).
• On-chip oscillator compensation with 64-position digital trim capacitor for ±30ppm accuracy.

Real Time Clock Applications

• Utility meters
• HVAC equipment
• Network routers, hubs, switches, and bridges

Real Time Clock Procurement Notes

Verify component authenticity and datasheet revision status prior to integration. Confirm that the specific ordering suffix corresponds to the required tape and reel packaging configuration. Ensure design compatibility with the specified VRESET threshold and I2C electrical characteristics for the target application environment.

Real Time Clock Selection Notes

Select this model when a 3.09V reset threshold is required for system supervision. The 'AZ' suffix indicates the TSSOP-14 package variant, while '-T' denotes tape and reel shipping. Verify that the host system supports the Legacy Mode power control settings associated with the standard ISL12028 architecture rather than the ISL12028A Standard Mode.

Real Time Clock Part Context

This component belongs to the ISL12028 family of real-time clocks produced by Renesas/Intersil. It is distinct from the ISL12028A series, which utilizes different power control settings. The IB30 designation specifically defines the internal reset voltage level and package type within this product line.

Real Time Clock Replacement Considerations

The manufacturer has designated this part as obsolete with no recommended replacement available. Engineers must evaluate alternative RTC solutions independently or utilize existing inventory for maintenance purposes.