ISL12027: Real Time Clock/Calendar with EEPROM

The ISL12027 device is a low power real time clock with timing and crystal compensation, clock/calender, power-fail indicator, two periodic or polled alarms, intelligent battery backup switching, CPU Supervisor and integrated 512x8-bit EEPROM, in 16 Byte per page format.

The oscillator uses an external, low-cost 32.768kHz crystal. The real time clock tracks time with separate registers for hours, minutes, and seconds. The device has calendar registers for date, month, year and day of the week. The calendar is accurate through 2099, with automatic leap year correction.

The ISL12027 and ISL12027A Power Control Settings are different. The ISL12027 uses the Legacy Mode Setting, and the ISL12027A uses the Standard Mode Setting. Applications that have VBAT > VDD will require only the ISL12027A.

Key Features
  • Real Time Clock/Calendar
    • Tracks Time in Hours, Minutes and Seconds
    • Day of the Week, Day, Month and Year
  • Two Non-Volatile Alarms
    • Settable on the Second, Minute, Hour, Day of the Week, Day, or Month
    • Repeat Mode (Periodic Interrupts)
  • Automatic Backup to Battery or SuperCap
  • On-Chip Oscillator Compensation
    • Internal Feedback Resistor and Compensation Capacitors
    • 64 Position Digitally Controlled Trim Capacitor
    • 6 Digital Frequency Adjustment Settings to ±30ppm
  • 512x8-Bits of EEPROM
    • 16-Byte Page Write Mode (32 total pages)
    • 8 Modes of BlockLock™ Protection
    • Single Byte Write Capability
  • High Reliability
    • Data Retention: 50 years
    • Endurance: >2,000,000 Cycles Per Byte
  • I2C-bus™ Interface
    • 400kHz Data Transfer Rate
  • 800nA Battery Supply Current
  • Package Options
    • 8 Ld SOIC and 8 Ld TSSOP Packages
  • Pb-Free (RoHS Compliant)
Applications
  • Utility Meters
  • HVAC Equipment
  • Audio/Video Components
  • Modems
  • Network Routers, Hubs, Switches, Bridges
  • Cellular Infrastructure Equipment
  • Fixed Broadband Wireless Equipment
  • Pagers/PDA
  • POS Equipment
  • Test Meters/Fixtures
  • Office Automation (Copiers, Fax)
  • Home Appliances
  • Computer Products
  • Other Industrial/Medical/Automotive
Typical Diagram
Application Notes
TitleTypeUpdatedSizeOther Languages
AN1549: Addressing Power Issues in Real Time Clock ApplicationsPDF13 Nov 201469 KB
AN1303: Replacing the X1226, X1227, X1228 or X1288 RTC with the ISL12026, ISL12027, ISL12028PDF13 Nov 201450 KB
Datasheets
TitleTypeUpdatedSizeOther Languages
ISL12027, ISL12027A DatasheetPDF12 Dec 2014398 KB
Software
TitleTypeUpdatedSizeOther Languages
Real Time Clock (RTC) Evaluation Installer for Windows 2000EXE31 Oct 20141.62 MB
Real Time Clock (RTC) Evaluation Installer for Windows 8EXE31 Oct 20147.85 MB
Real Time Clock (RTC) Evaluation Installer for Windows XP / Windows 7EXE31 Oct 20143.02 MB
Tech Briefs
TitleTypeUpdatedSizeOther Languages
TB460: Replacing the x1226, x1227 or x1228 RTC with the ISL12026, ISL12026A, ISL12027 or ISL12028PDF19 Nov 201440 KB
User Guides
TitleTypeUpdatedSizeOther Languages
Real Time Clock USB Evaluation Board User GuidePDF12 May 2015487 KB
Miscellaneous
TitleTypeUpdatedSizeOther Languages
RTC WIN8 Preinstallation ProcedurePDF19 Nov 2014849 KB
Order Information
Part NumberPackage TypeWeight(g)PinsMSL RatingPeak Temp (°C)RoHS Status
ISL12027IB27AZ8 Ld SOIC0.07281260RoHS
ISL12027IB27AZ-T8 Ld SOIC T+R0.07281260RoHS
ISL12027IB27Z8 Ld SOIC0.07281260RoHS
ISL12027IB27Z-T8 Ld SOIC T+R0.07281260RoHS
ISL12027IB30AZ8 Ld SOIC0.07281260RoHS
ISL12027IB30AZ-T8 Ld SOIC T+R0.07281260RoHS
ISL12027IBAZ8 Ld SOIC0.07281260RoHS
ISL12027IBAZ-T8 Ld SOIC T+R0.07281260RoHS
ISL12027IBZ8 Ld SOIC0.07281260RoHS
ISL12027IBZ-T8 Ld SOIC T+R0.07281260RoHS
ISL12027IV27AZ8 Ld TSSOP0.03381260RoHS
ISL12027IV27AZ-T8 Ld TSSOP T+R0.03381260RoHS
ISL12027IV27Z8 Ld TSSOP0.03381260RoHS
ISL12027IV27Z-T8 Ld TSSOP T+R0.03381260RoHS
ISL12027IV30AZ8 Ld TSSOP0.03381260RoHS
ISL12027IV30AZ-T8 Ld TSSOP T+R0.03381260RoHS
ISL12027IVAZ8 Ld TSSOP0.03381260RoHS
ISL12027IVAZ-T8 Ld TSSOP T+R0.03381260RoHS
ISL12027IVZ8 Ld TSSOP0.03381260RoHS
ISL12027IVZ-T8 Ld TSSOP T+R0.03381260RoHS
Datasheet
ISL12027, ISL12027A Datasheet 12 Dec 2014
Other
AN1303: Replacing the X1226, X1227, X1228 or X1288 RTC with the ISL12026, ISL12027, ISL12028 13 Nov 2014
AN1549: Addressing Power Issues in Real Time Clock Applications 13 Nov 2014
Real Time Clock USB Evaluation Board User Guide 12 May 2015
ISL12027A
8 Ld SOIC T+R ISL84514
8 Ld TSSOP T+R ISL12024
Real Time Clock (RTC) Evaluation Installer for Windows XP / Windows 7 31 Oct 2014
Real Time Clock (RTC) Evaluation Installer for Windows 2000 31 Oct 2014
Real Time Clock (RTC) Evaluation Installer for Windows 8 31 Oct 2014
RTC WIN8 Preinstallation Procedure 19 Nov 2014
TB460: Replacing the x1226, x1227 or x1228 RTC with the ISL12026, ISL12026A, ISL12027 or ISL12028 19 Nov 2014