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FEATURES
Real-Time Clock (RTC) Counts Seconds,
Minutes, Hours, Date of the Month, Month,
Day of the Week, and Year with Leap-Year
Compensation Valid Up to 2100
96-Byte, Battery-Backed NV RAM for Data
Storage
Two Time-of-Day Alarms, Programmable on
Combination of Seconds, Minutes, Hours,
and Day of the Week
1Hz and 32.768kHz Clock Outputs
Supports Motorola SPI (Serial Peripheral
Interface) Modes 1 and 3 or Standard 3-Wire
Interface
Burst Mode for Reading/Writing Successive
Addresses in Clock/RAM
Dual-Power Supply Pins for Primary and
Backup Power Supplies
Optional Trickle Charge Output to Backup
Supply
2.0V to 5.5V Operation
Optional Industrial Temperature Range:
-40°C to +85°C
Available in Space-Efficient, 20-Pin TSSOP
Package
Underwriters Laboratory (UL) Recognized
PIN CONFIGURATIONS
www.maxim-ic.com
DS1306
Serial Alarm Real-Time Clock
SPI is a trademark of Motorola, Inc.
TSSOP (4.4mm)
VCC2
VBAT
X1
N.C.
X2
N.C.
INT0
INT1
1Hz
GND
VCC1
N.C.
32kHz
VCCIF
SDO
SDI
SCLK
CE
SERMODE
N.C.
20
19
18
17
16
15
14
13
12
11
1
2
3
4
5
6
7
8
9
10
VCC2
DIP (300 mils)
15
X1
INT0
1Hz
GND
VCC1
SDO
SDI
SCLK
CE
SERMODE
1
2
3
4
5
6
7
8
16
14
13
12
11
10
9
VBAT
X2
INT1
32kHz
VCCIF
19-5056; Rev 12/09