DATASHEET
REAL-TIME CLOCK WITH I
2
C SERIAL INTERFACE
General Description
The IDT1337 device is a low power serial real-time clock
(RTC) device with two programmable time-of-day alarms
and a programmable square-wave output. Address and
data are transferred serially through an I
2
C bus. The device
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.
IDT1337
Features
•
Real-Time Clock (RTC) counts seconds, minutes, hours,
day, date, month, and year with leap-year compensation
valid up to 2100
•
Packaged in 8-pin MSOP, 8-pin SOIC, or 16-pin SOIC
(surface-mount package with an integrated crystal)
Applications
•
•
•
•
•
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Telecommunication (Routers, Switches, Servers)
Handhelds (GPS, POS terminals, MP3 players)
Set-Top Box, Digital Recording,
Office (Fax/Printers, Copiers)
Medical (Glucometer, Medicine Dispensers)
Other (Thermostats, Vending Machines, Modems, Utility
Meters, Digital Photo Frame devices)
•
•
•
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I
2
C Serial interface (Normal and Fast modes)
Two time-of-day alarms
Oscillator Stop Flag
Programmable square-wave output defaults to 32 kHz on
power-up
•
Operating voltage of 1.8 to 5.5 V
•
Industrial temperature range (-40 to +85°C)
Block Diagram
VCC
Crystal inside package
for 16-pin SOIC ONLY
X1
1 Hz/4.096 kHz/
8.192 kHz/32.768 kHz
32.768 kHz
Oscillator and
Divider
MUX/
Buffer
SQW/INTB
INTA
X2
Control
Logic
Clock,
Calendar
Counter
SCL
SDA
I
2
C
Interface
1 Byte
Control
7 Bytes
Buffer
Alarm
Registers
GND
IDT™
REAL-TIME CLOCK WITH I
2
C SERIAL INTERFACE
1
IDT1337
REV J 111009
IDT [ INTEGRATED DEVICE TECHNOLOGY ]
