ICL7673: Automatic Battery Back-Up Switch

The Intersil ICL7673 is a monolithic CMOS battery backup circuit that offers unique performance advantages over conventional means of switching to a backup supply. The ICL7673 is intended as a low-cost solution for the switching of systems between two power supplies; main and battery backup. The main application is keep-alive-battery power switching for use in volatile CMOS RAM memory systems and real time clocks. In many applications this circuit will represent a low insertion voltage loss between the supplies and load. This circuit features low current consumption, wide operating voltage range, and exceptionally low leakage between inputs. Logic outputs are provided that can be used to indicate which supply is connected and can also be used to increase the power switching capability of the circuit by driving external PNP transistors.

Key Features
  • Automatically Connects Output to the Greater of Either Input Supply Voltage
  • If Main Power to External Equipment is Lost, Circuit Will Automatically Connect Battery Backup
  • Reconnects Main Power When Restored
  • Logic Indicator Signaling Status of Main Power
  • Low Impedance Connection Switches
  • Low Internal Power Consumption
  • Wide Supply Range: 2.5V to 15V
  • Low Leakage Between Inputs
  • External Transistors May Be Added if Very Large Currents Need to Be Switched
  • Pb-Free Plus Anneal Available (RoHS Compliant)
Applications
  • On Board Battery Backup for Real-Time Clocks, Timers, or Volatile RAMs
  • Over/Under Voltage Detector
  • Peak Voltage Detector
  • Other Uses:
    • Portable Instruments, Portable Telephones, Line Operated Equipment
Typical Diagram
Datasheets
TitleTypeUpdatedSizeOther Languages
ICL7673 DatasheetPDF03 Dec 2015193 KB
White Papers
TitleTypeUpdatedSizeOther Languages
Five Easy Steps to Create a Multi-Load Power SolutionPDF30 Jan 2017502 KB
Order Information
Part NumberPackage TypeWeight(g)PinsMSL RatingPeak Temp (°C)RoHS Status
ICL7673CBA8 Ld SOIC0.07281240
ICL7673CBA-T8 Ld SOIC T+R0.07281240
ICL7673CBAZA8 Ld SOIC0.07281260RoHS
ICL7673CBAZA-T8 Ld SOIC T+R0.07281260RoHS
ICL7673CPA8 Ld PDIP0.548N/ANA
ICL7673CPAZ8 Ld PDIP0.548N/ANARoHS
ICL7673 Datasheet 03 Dec 2015
8 Ld SOIC T+R ISL84514
8 Ld PDIP ISL84542
ICL7673
Five Easy Steps to Create a Multi-Load Power Solution 30 Jan 2017