The 1338 is a serial real-time clock (RTC) device that consumes ultra-low power and provides a full binary-coded decimal (BCD) clock/calendar with 56 bytes of battery backed Non-Volatile Static RAM. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The clock operates in either the 24-hour or 12-hour format with AM/PM indicator. The end of the month date is automatically adjusted for months with fewer than 31 days, including corrections for leap year. Access to the clock/calendar registers is provided by an I2C interface capable of operating in fast I2C mode. Built-in Power-sense circuitry detects power failures and automatically switches to the backup supply, maintaining time and date operation.

Features

  • Real-Time Clock (RTC) counts seconds, minutes, hours, day, date, month, and year with leap-year compensation valid up to 2100
  • 56-Byte battery-backed Non Volatile RAM for data storage
  • Fast mode I2C Serial interface
  • Automatic power-fail detect and switch circuitry
  • Programmable square-wave output
  • Packaged in 8-pin MSOP, 8-pin SOIC, or 16-pin SOIC (surface-mount package with an integrated crystal)
  • Industrial temperature range (-40°C to +85°C)

descriptionDocumentation

Title language Type Format File Size Date
Datasheets & Errata
star 1338 Datasheet – Datasheet PDF 427 KB
Errata# : UEN-13-01 – Datasheet Errata PDF 421 KB
1338B-31 Datasheet – Datasheet PDF 541 KB
Application Notes & White Papers
AN-828 Termination - LVPECL – Application Note PDF 322 KB
AN-844 Termination - AC Coupling Clock Receivers – Application Note PDF 170 KB
AN-845 Termination - LVCMOS – Application Note PDF 146 KB
AN-842 Thermal Considerations in Package Design and Selection – Application Note PDF 495 KB
AN-840 Jitter Specifications for Timing Signals – Application Note PDF 442 KB
AN-838 Peak-to-Peak Jitter Calculations – Application Note PDF 115 KB
AN-839 RMS Phase Jitter – Application Note PDF 233 KB
AN-815 Understanding Jitter Units – Application Note PDF 565 KB
AN-827 Application Relevance of Clock Jitter – Application Note PDF 1.15 MB
AN-805 Recommended Ferrite Beads – Application Note PDF 121 KB
PCNs & PDNs
PCN# : A2003-01 Add Greatek Taiwan as an Alternate Assembly Location on Select Packages – Product Change Notice PDF 113 KB
PDN#: CQ-19-04 Product Discontinuance Notice – Product Discontinuation Notice PDF 1010 KB
PCN# : A1602-01(R1) Add Greatek Taiwan as Alternate Assembly – Product Change Notice PDF 611 KB
PCN# : A1602-01 Add Greatek Taiwan as Alternate Assembly – Product Change Notice PDF 611 KB
PDN# : CQ-14-08 Manufacturing Discontinunce PDN – Product Discontinuation Notice PDF 486 KB
PCN# : A1403-03 Gold wire to Copper wire – Product Change Notice PDF 42 KB
PCN# : W1101-02R4 Fab 4 to TSMC – Product Change Notice PDF 70 KB
PCN# : W1101-02R3 Fab 4 to TSMC – Product Change Notice PDF 71 KB
PCN# : W1101-02R2 Fab 4 to TSMC – Product Change Notice PDF 67 KB
PCN# : A1208-01R1 Gold to Copper Wire – Product Change Notice PDF 254 KB
PCN# : A1208-06 Changed of Assembly Location and Crystal – Product Change Notice PDF 1.06 MB
PCN# : A1204-01R1 Revised Notification to Remove Selective Devices from TSSOP-16 – Product Change Notice PDF 332 KB
Other
IDT Clock Generation Overview – Overview PDF 1.83 MB
Real Time Clocks – Product Brief PDF 441 KB
info: For device-specific or order-specific documentation, submit a support request.

printNews & Additional Resources

Type Date
An Insider’s Guide to Finding the Right Timing Device for Your System Blog Post Dec 19, 2017
Why Fanout Buffers Make More Sense Blog Post Nov 29, 2017
IDT Introduces Ultra Low Power Timing Solutions for Applications Requiring Stand-Alone Real-Time Clocks News May 27, 2008