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GENERAL DESCRIPTION

The DS1339 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 I

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 DS1339 has a built-in power-

sense

circuit

that

detects

power

failures

and

automatically

switches

to

the

backup

supply,

maintaining time, date, and alarm operation.

APPLICATIONS

Handhelds (GPS, POS Terminals)

Consumer Electronics (Set-Top Box, Digital

Recording, Network Appliance)

Office Equipment (Fax/Printers, Copier)

Medical (Glucometer, Medicine Dispenser)

Telecommunications (Routers, Switches, Servers)

Other (Utility Meter, Vending Machine, Thermostat,

Modem

)

FEATURES



Real-Time Clock (RTC) Counts Seconds, Minutes,

Hours, Day, Date, Month, and Year with Leap-

Year Compensation Valid Up to 2100



Available in a Surface-Mount Package with an

Integrated Crystal (DS1339C)



I



Two Time-of-Day Alarms



Programmable Square-Wave Output



Oscillator Stop Flag



Automatic Power-Fail Detect and Switch Circuitry



Trickle-Charge Capability



Underwriters Laboratories (UL) Recognized

Pin Configurations appear at end of data sheet.

ORDERING INFORMATION

PART

TEMP RANGE

VOLTAGE (V)

PIN-PACKAGE

TOP MARK†

DS1339C-2#

-40°C to +85°C

2.0

16 SO (300 mils)

DS1339C-2

DS1339C-3#

-40°C to +85°C

3.0

16 SO (300 mils)

DS1339C-3

DS1339C-33#

-40°C to +85°C

3.3

16 SO (300 mils)

DS1339C-33

DS1339U-2+

-40°C to +85°C

2.0

8

µSOP

1339 rr-2

DS1339U-3+

-40°C to +85°C

3.0

8

µSOP

1339 rr-3

DS1339U-33+

-40°C to +85°C

3.3

8

µSOP

1339 rr-33

+Denotes a lead(Pb)-free/RoHS-compliant package.

#Denotes a RoHS-compliant device that may include lead that is exempt under the RoHS requirements. The lead finish is JESD97 category

e3, and is compatible with both lead-based and lead-free soldering processes.

†A “+” anywhere on the top mark indicates a lead(Pb)-free device. A “#” denotes a RoHS-compliant device. rr = second line, revision code

DS1339

I

19-5770; Rev 4/11