Maxim > Products > Real-time clocks (RTCs) > DS1338, DS1338C, DS1338U, ...

DS1338, DS1338C, DS1338U, DS1338Z
I²C RTC with 56-Byte NV RAM

Overview

Technical Documents

Ordering Info

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All

Status
Part Number	Status
DS1338	Active: In Production.
DS1338C	Active: In production, but some versions are no longer available. See Ordering Information.
DS1338U	Active: In production, but some versions are no longer available. See Ordering Information.
DS1338Z	Active: In Production.

Data Sheet

FULL DATA SHEET Download Rev 7 (PDF, 268kB) E-Mail

Description

The DS1338 serial real-time clock (RTC) is a low-power, full binary-coded decimal (BCD) clock/calendar plus 56 bytes of NV SRAM. Address and data are transferred serially through an I²C interface. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The end of the month date 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 DS1338 has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply, maintaining time and date operation.

Key Features		Applications/Uses
RTC Counts Seconds, Minutes, Hours, Date of the Month, Month, Day of the Week, and Year with Leap-Year Compensation Valid Up to 2100 Available in a Surface-Mount Package with an Integrated Crystal (DS1338C) 56-Byte Battery-Backed General-Purpose RAM with Unlimited Writes I²C Serial Interface Programmable Square-Wave Output Signal Automatic Power-Fail Detect and Switch Circuitry -40°C to +85°C Operating Temperature Range Underwriters Laboratories (UL®) Recognized		Consumer Electronics (Set-Top Box, Digital Recording, Network Appliance) Handhelds (GPS, POS Terminal) Medical (Glucometer, Medicine Dispenser) Office Equipment (Fax/Printer, Copier) Other (Utility Meter, Vending Machine, Thermostat, Modem) Telecommunications (Router, Switcher, Server)

Diagram

Typical Operating Circuit

Application Notes
Application Note 58	Crystal Considerations with Dallas Real-Time Clocks (RTCs)
Application Note 504	Design considerations for Dallas Semiconductor real-time clocks
Application Note 505	Lithium Coin-Cell Batteries: Predicting an Application Lifetime
Application Note 701	Using the DS32kHz with Dallas Real-Time Clocks
Application Note 3572	FAQ about the integrated-crystal package option
Application Note 3816	Selecting a Backup Source for Real-Time Clocks
Application Note 3921	Using a DS1307 with a PIC Microcontroller

Design Guides

Real-Time Clocks (PDF)

Reliability Reports
Reliability Report:	DS1338.pdf
Request Reliability Report for:	DS1338C DS1338U DS1338Z
Underwriters Laboratories (UL®) Recognized

Software/Models

none

Ordering Information

Notes: Other options and links for purchasing parts are listed at: http://www.maxim-ic.com/sales. Didn't Find What You Need? Ask our applications engineers. Expert assistance in finding parts, usually within one business day. Part number suffixes: T or T&R = tape and reel; + = RoHS/lead-free; # = RoHS/lead-exempt; -D = drypack; -U/+U on DS parts = cut tape. More: See Full Data Sheet or Maxim Product Naming Conventions. * Some packages have variations, listed on the drawing. "PkgCode/Variation" tells which variation the product uses. Note that "+", "#", "-" in the part number suffix describes RoHS status. Package drawings may show a different suffix character.

Filters

Part Number: Package: Any -------- USOP SOIC Temperature: Any -------- -40°C to +85°C Tape and Reel

DS1338C	Free Sample	Buy	Status	Recommended Replacement	Package: TYPE PINS FOOTPRINT   DRAWING CODE/VAR *	Temp	RoHS/Lead-Free? Materials Analysis
DS1338C-3		N/A	No Longer Available	DS1338C-3#	SOIC(W);16 pin;110.6 mm² Outline Drawing:21-0042 (PDF) Land Pattern: 90-0107 (PDF) Use pkgcode/variation: W16-H2*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338C-3#			Active		SOIC(W);16 pin;110.6 mm² Outline Drawing:21-0042 (PDF) Land Pattern: 90-0107 (PDF) Use pkgcode/variation: W16#H2*	-40°C to +85°C	RoHS/Lead-Free: RoHS Qualified Materials Analysis
DS1338C-33#T&R			Active		SOIC(W);16 pin;110.6 mm² Outline Drawing:21-0042 (PDF) Land Pattern: 90-0107 (PDF) Use pkgcode/variation: W16#H2*	-40°C to +85°C	RoHS/Lead-Free: RoHS Qualified Materials Analysis
DS1338C-33			Active		SOIC(W);16 pin;110.6 mm² Outline Drawing:21-0042 (PDF) Land Pattern: 90-0107 (PDF) Use pkgcode/variation: W16-H2*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338C-33#			Active		SOIC(W);16 pin;110.6 mm² Outline Drawing:21-0042 (PDF) Land Pattern: 90-0107 (PDF) Use pkgcode/variation: W16#H2*	-40°C to +85°C	RoHS/Lead-Free: RoHS Qualified Materials Analysis
DS1338C-18#			Active		SOIC(W);16 pin;110.6 mm² Outline Drawing:21-0042 (PDF) Land Pattern: 90-0107 (PDF) Use pkgcode/variation: W16#H2*	-40°C to +85°C	RoHS/Lead-Free: RoHS Qualified Materials Analysis
DS1338C-18			Active		SOIC(W);16 pin;110.6 mm² Outline Drawing:21-0042 (PDF) Land Pattern: 90-0107 (PDF) Use pkgcode/variation: W16-H2*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338U	Free Sample	Buy	Status	Recommended Replacement	Package: TYPE PINS FOOTPRINT   DRAWING CODE/VAR *	Temp	RoHS/Lead-Free? Materials Analysis
DS1338U-33+T&R/C01			Active		µMAX;8 pin;16.2 mm² Outline Drawing:21-0036 (PDF) Land Pattern: 90-0092 (PDF) Use pkgcode/variation: U8+1*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
DS1338UA-33+T&R		N/A	No Longer Available	DS1338	USOP; Land Pattern: Not Available	-40°C to +85°C	See data sheet
DS1338UA-33+		N/A	No Longer Available	DS1338	USOP; Land Pattern: Not Available	-40°C to +85°C	See data sheet
DS1338U-18+			Active		µMAX;8 pin;16.2 mm² Outline Drawing:21-0036 (PDF) Land Pattern: 90-0092 (PDF) Use pkgcode/variation: U8+1*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
DS1338U-33/T&R			Active		µMAX;8 pin;16.2 mm² Outline Drawing:21-0036 (PDF) Land Pattern: 90-0092 (PDF) Use pkgcode/variation: U8-1*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338U-33+T&R			Active		µMAX;8 pin;16.2 mm² Outline Drawing:21-0036 (PDF) Land Pattern: 90-0092 (PDF) Use pkgcode/variation: U8+1*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
DS1338U-33+			Active		µMAX;8 pin;16.2 mm² Outline Drawing:21-0036 (PDF) Land Pattern: 90-0092 (PDF) Use pkgcode/variation: U8+1*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
DS1338U-33			Active		µMAX;8 pin;16.2 mm² Outline Drawing:21-0036 (PDF) Land Pattern: 90-0092 (PDF) Use pkgcode/variation: U8-1*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338U-18			Active		µMAX;8 pin;16.2 mm² Outline Drawing:21-0036 (PDF) Land Pattern: 90-0092 (PDF) Use pkgcode/variation: U8-1*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338U-3+T&R			Active		µMAX;8 pin;16.2 mm² Outline Drawing:21-0036 (PDF) Land Pattern: 90-0092 (PDF) Use pkgcode/variation: U8+1*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
DS1338U-3+			Active		µMAX;8 pin;16.2 mm² Outline Drawing:21-0036 (PDF) Land Pattern: 90-0092 (PDF) Use pkgcode/variation: U8+1*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
DS1338U-3			Active		µMAX;8 pin;16.2 mm² Outline Drawing:21-0036 (PDF) Land Pattern: 90-0092 (PDF) Use pkgcode/variation: U8-1*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338Z	Free Sample	Buy	Status	Recommended Replacement	Package: TYPE PINS FOOTPRINT   DRAWING CODE/VAR *	Temp	RoHS/Lead-Free? Materials Analysis
DS1338Z-3/T&R			Active		SOIC(N);8 pin;30.9 mm² Outline Drawing:21-0041 (PDF) Land Pattern: 90-0096 (PDF) Use pkgcode/variation: S8-2*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338Z-3+T&R			Active		SOIC(N);8 pin;30.9 mm² Outline Drawing:21-0041 (PDF) Land Pattern: 90-0096 (PDF) Use pkgcode/variation: S8+4*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
DS1338Z-3			Active		SOIC(N);8 pin;30.9 mm² Outline Drawing:21-0041 (PDF) Land Pattern: 90-0096 (PDF) Use pkgcode/variation: S8-2*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338Z-3+			Active		SOIC(N);8 pin;30.9 mm² Outline Drawing:21-0041 (PDF) Land Pattern: 90-0096 (PDF) Use pkgcode/variation: S8+4*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
DS1338Z-18+			Active		SOIC(N);8 pin;30.9 mm² Outline Drawing:21-0041 (PDF) Land Pattern: 90-0096 (PDF) Use pkgcode/variation: S8+4*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
DS1338Z-33+			Active		SOIC(N);8 pin;30.9 mm² Outline Drawing:21-0041 (PDF) Land Pattern: 90-0096 (PDF) Use pkgcode/variation: S8+2*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis
DS1338Z-18			Active		SOIC(N);8 pin;30.9 mm² Outline Drawing:21-0041 (PDF) Land Pattern: 90-0096 (PDF) Use pkgcode/variation: S8-2*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338Z-33			Active		SOIC(N);8 pin;30.9 mm² Outline Drawing:21-0041 (PDF) Land Pattern: 90-0096 (PDF) Use pkgcode/variation: S8-2*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338Z-33/T&R			Active		SOIC(N);8 pin;30.9 mm² Outline Drawing:21-0041 (PDF) Land Pattern: 90-0096 (PDF) Use pkgcode/variation: S8-2*	-40°C to +85°C	RoHS/Lead-Free: No Materials Analysis
DS1338Z-33+T&R			Active		SOIC(N);8 pin;30.9 mm² Outline Drawing:21-0041 (PDF) Land Pattern: 90-0096 (PDF) Use pkgcode/variation: S8+2*	-40°C to +85°C	RoHS/Lead-Free: Lead Free Materials Analysis

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Rev 7; 2008-10-02
This page last modified: 2009-06-04