ISL1208IU8Z-TK

Real Time Clock Overview

The ISL1208IU8Z-TK is a low-power real-time clock (RTC) and calendar integrated circuit manufactured by Renesas Electronics Corporation. It operates within a supply voltage range of 2.7 V to 5.5 V and features an I2C serial interface with a data transfer rate up to 400 kHz. The device tracks time in hours, minutes, and seconds, and includes calendar registers for date, month, year, and day of the week, accurate through 2099 with automatic leap year correction. It utilizes an external 32.768 kHz crystal and offers 2 bytes of battery-backed user SRAM. The component is housed in an 8-MSOP package and supports operation temperatures from -40°C to +85°C.

Real Time Clock Feature Summary

• I2C Serial Interface: Supports standard and fast mode communication at up to 400 kHz.
• Calendar Functionality: Tracks time and date with automatic leap year correction valid through 2099.
• Low Power Consumption: Battery supply current is typically 400 nA; main supply current ranges from 4 µA to 6 µA at 3V–5V.
• Battery Backup Switching: Automatically switches between main power and backup source (battery or super capacitor) upon power failure detection.

Real Time Clock Applications

• Smart meters and utility monitoring systems requiring precise timekeeping.
• Industrial control equipment needing reliable calendar and alarm functions.
• Portable electronic devices where low standby current is critical.

Real Time Clock Procurement Notes

Verify the specific suffix 'TK' against official Renesas documentation to confirm packaging details, as standard listings often use 'T7A' for tape-and-reel MSOP variants. Ensure compatibility with existing I2C bus protocols and check for any recent Product Change Notifications (PCNs) regarding labeling or assembly sites. Confirm that the 8-MSOP footprint matches the design schematic before procurement.

Real Time Clock Selection Notes

Select this component when an I2C-compatible RTC with integrated calendar and battery-backed SRAM is required in a small surface-mount package. It is suitable for designs operating between 2.7 V and 5.5 V. Consider the ISL1208 family if pin compatibility with ST M41Txx or Maxim DS13xx devices is needed for drop-in replacements. Verify that the application can accommodate an external 32.768 kHz crystal oscillator.

Real Time Clock Part Context

The ISL1208 series comprises low-power RTCs with timing compensation and power-fail indicators. The ISL1208IU8Z-TK specifically denotes the MSOP-8 package variant. Other variants in the family include SOIC-8 (ISL1208IB8Z) and TDFN-8 (ISL1208IRT8Z) packages, offering flexibility for different PCB layout constraints while maintaining identical functional specifications.

Real Time Clock Replacement Considerations

Direct pin-compatible alternatives within the same family include ISL1208IB8Z (SOIC-8) and ISL1208IRT8Z (TDFN-8). Cross-brand replacements such as ST M41T62 or Maxim DS1307 may require schematic review due to potential register or pinout differences despite similar functionality.