Document
ISL12022
Low Power RTC with Battery-Backed SRAM and Embedded Temp Compensation ±5ppm with Auto Daylight Saving
FN6659 Rev.3.01 Oct 24, 2019
The ISL12022 device is a low power real time clock with an embedded Temp sensor for oscillator compensation, clock/calendar, power fail, low battery monitor, brownout indicator, single periodic or polled alarms, intelligent battery-backup switching, Battery Reseal™ function, and 128 bytes of battery-backed user SRAM.
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.
Daylight Savings time adjustment is done automatically, using parameters entered by the user. Power fail and battery monitors offer user-selectable trip levels. A time stamp function records the time and date of switchover from VDD to VBAT power, and also from VBAT to VDD power.
Applications
• Utility Meters
• POS Equipment
• Medical Devices
• Security Systems
• Vending Machines
• White Goods
• Printers and Copiers
Related Literature
For a full list of related documents, visit our website
• ISL12022 device page
Features
• Real Time Clock/Calendar - Tracks Time in Hours, Minutes and Seconds - Day of the Week, Day, Month, and Year
• On-chip Oscillator Compensation Over the Operating Temperature Range - ±5ppm Over -40°C to +85°C
• 10-bit Digital Temperature Sensor Output - ±2°C Accuracy
• Customer Programmable Day Light Saving Time
• 15 Selectable Frequency Outputs
• 1 Alarm - Settable to the Second, Minute, Hour, Day of the Week, Day, or Month - Single Event or Pulse Interrupt Mode
• Battery Reseal™ Function to Extend Battery Shelf Life
• Automatic Backup to Battery or Super Capacitor - Operation to VBAT = 1.8V - 1.0µA Battery Supply Current
• Battery Status Monitor - 2 User Programmable Levels - Seven Selectable Voltages for Each Level
• Power Status Brownout Monitor - Six Selectable Trip Levels, from 2.295V to 4.675V
• Oscillator Failure Detection
• Time Stamp for First VDD to VBAT, and Last VBAT to VDD • 128 Bytes Battery-Backed User SRAM • I2C Bus™
- 400kHz Clock Frequency
• 1µA Typical Battery Current
• Pb-Free (RoHS Compliant)
VDD = 2.7V TO 5.5V CIN 0.1µF
ISL12022 VDD VBAT
GND
JBAT
DBAT BAT43W CBAT 0.1µF
+ VBAT = 1.8V TO 3.2V
FIGURE 1. TYPICAL APPLICATION CIRCUIT
FN6659 Rev.3.01 Oct 24, 2019
Page 1 of 32
ISL12022
Table of Contents
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pin Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Pin Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Thermal Informati.