Maxim Supplier Page

Low-Current, I²C, Serial Real-Time Clock

Maxim's DS1339A serial real-time clock (RTC) is a low-power programmable clock/date device

Maxim - DS1339AMaxim's DS1339A serial real-time clock (RTC) is a low-power clock/date device with two programmable time-of-day alarms and a programmable square-wave output. Address and data are transferred serially through an I²C bus. The clock/date provides seconds, minutes, hours, day, date, month, and year information. The date at the end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the 24-hour or 12-hour format with AM/PM indicator. The DS1339A has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply, maintaining time, date, and alarm operation.

  • Drop-in replacement for DS1339
  • Real-Time Clock (RTC) counts seconds, minutes, hours, day, date, month, and year with leap-year compensation
  • I²C serial interface
  • 2-time-of-day alarms
  • Programmable square-wave output
  • Oscillator stop flag
  • Automatic power-fail detect and switch circuitry
  • Trickle-charge capability

  • Consumer electronics (Set-Top Box, Digital Recording, Network Appliance)
  • Handhelds (GPS, POS Terminals)
  • Medical (Glucometer, Medicine dispenser)
  • Office equipment (Fax, Printer, Copier)
  • Telecommunications (Routers, Switches, Servers)
  • Other (Utility Meter, Vending Machine, Thermostat, Modem)

Digi-Key P/N Manufacturer P/N Package Description  
DS1339AU+-ND DS1339AU+ Tube IC RTC I2C W/ALARM 8USOP Datasheet