DS1337, DS1337C:I²C Serial Real-Time Clock

Industry's Smallest I²C RTC with Two Time-of-Day Alarms

The DS1337 serial real-time clock is a low-power clock/calendar 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/calendar 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 device is fully accessible through the serial interface while VCC is between 1.8V and 5.5V. I²C operation is not guaranteed below 1.8V. Timekeeping operation is maintained with VCC as low as 1.3V.

Key Features
  • Completely Manages All Timekeeping Functions
    • Real-Time Clock (RTC) Counts Seconds, Minutes, Hours, Day, Date, Month, and Year with Leap-Year Compensation Valid Up to 2100
    • Two Time-of-Day Alarms
    • Programmable Square-Wave Output Defaults to 32kHz on Power-Up
    • Oscillator Stop Flag
  • Interfaces with Most Microcontrollers
    • I2C Serial Interface
  • Surface-Mount Package with an Integrated Crystal (DC1337C) Saves Additional Space and Simplifies Design
  • -40°C to +85°C Industrial Temperature Range Supports Operation in a Wide Range of Applications
DS1337, DS1337C: Typical Operating Circuit
DS1337, DS1337C: Typical Operating Circuit
Applications/Uses
  • Consumer Electronics (Set-Top Box, VCR/Digital Recording)
  • Handhelds (GPS, POS Terminal, MP3 Player)
  • Medical (Glucometer, Medicine Dispenser)
  • Office Equipment (Fax/Printer, Copier)
  • Other (Utility Meter, Vending Machine, Thermostat, Modem)
  • Telecommunications (Router, Switcher, Server)
DataSheet
titleDownload file
DS1337-DS1337C Data SheetDS1337-DS1337C.pdf
Parametrics
Part NumberInterfaceVSUPPLY
(V)
Time Keeping Current
(nA)
CL
(pF)
Memory TypeTime of Day AlarmsIntegrated ResonatorFunctionsPackage/PinsBudgetary
Price
typSee Notes
DS1337I2C2
3
3.3
5
4256None2-RTCµMAX/8
PDIP(N)/8
SOIC/16
SOIC(N)/8
$1.16 @1k
DS1337CXTALµMAX/8
PDIP(N)/8
SOIC/16
SOIC(N)/8
$2.39 @1k
Quality and Environmental Data
Related Products
  • DS1342:Low-Current I²C RTCs for High-ESR Crystals
  • DS1341:Low-Current I²C RTCs for High-ESR Crystals
  • DS1371:I²C, 32-Bit Binary Counter Watchdog Clock
  • DS1339:I²C Serial Real-Time Clock
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
DS1337No Longer AvailableDS1337+PDIP(N),;8 pin;79.7 mm²-40°C to +85°CNo
DS1337+ActivePDIP(N),;8 pin;79.7 mm²-40°C to +85°CLead Free
DS1337CNo Longer AvailableDS1337C#SOIC,;16 pin;SOIC (;16 pin-40°C to +85°CNo
DS1337C#ActiveSOIC,;16 pin;SOIC (;16 pin-40°C to +85°C
DS1337C#T&RActiveSOIC,;16 pin;SOIC (;16 pin-40°C to +85°C
DS1337C/T&RNo Longer AvailableDS1337C#T&RSOIC,;16 pin;SOIC (;16 pin-40°C to +85°CNo
DS1337SNo Longer AvailableDS1337S+SOIC(N),;8 pin;30.9 mm²-40°C to +85°CNo
DS1337S+ActiveSOIC(N),;8 pin;30.9 mm²-40°C to +85°CLead Free
DS1337S+T&RActiveSOIC(N),;8 pin;30.9 mm²-40°C to +85°CLead Free
DS1337S/T&RNo Longer AvailableDS1337S+T&RSOIC(N),;8 pin;30.9 mm²-40°C to +85°CNo
Part NumberStatusRecommended ReplacementPackageTempRoHS
DS1337UNo Longer AvailableDS1337U+µMAX,;8 pin;15.6 mm²-40°C to +85°CNo
DS1337U+ActiveµMAX,;8 pin;15.6 mm²-40°C to +85°CLead Free
DS1337U+T&RActiveµMAX,;8 pin;15.6 mm²-40°C to +85°CLead Free
DS1337U/T&RNo Longer AvailableDS1337U+T&RµMAX,;8 pin;15.6 mm²-40°C to +85°CNo
DS1337-DS1337C.pdf DS1337C
Tips for Writing Bulletproof Real-Time Clock Control Code DS3234
State Machine Logic in Binary-Coded Decimal (BCD)-Formatted Real-Time Clocks DS3234
Oscillator Design Considerations for Low-Current Applications DS17885
Selecting a Backup Source for Real-Time Clocks DS3234
Using the DS32kHz with Maxim Real-Time Clocks DS17885
Lithium Coin-Cell Batteries: Predicting an Application Lifetime DS9034PCX
Design Considerations for Maxim Real-Time Clocks DS3234
Crystal Considerations with Maxim Real-Time Clocks (RTCs) DS3234
DS1337C.pdf DS1337C
DS1337.pdf DS1337C
DS1337-DS1337C.pdf DS1337C