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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
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:
-
C to +85C
Available in Space-Efficient, 20-Pin TSSOP
Package
Underwriters Laboratory (UL) Recognized
PIN CONFIGURATIONS
TYPICAL OPERATING CIRCUIT
www.maxim-ic.com
DS1305
Serial Alarm Real-Time Clock
SPI is a trademark of Motorola, Inc.
VCC2
1
16
VCC1
VBAT
2
15
PF
X1
3
14
VCCIF
X2
4
13
SDO
N.C.
5
12
SDI
INT0
6
11
SCLK
INT1
7
10
CE
GND
8
9
SERMODE
DIP (300 mils)
DS1305
VCC2
1
20
VCC1
VBAT
2
19
N.C.
X1
3
18
PF
N.C.
4
17
VCCIF
X2
5
16
SD0
N.C.
6
15
SDI
INT0
7
14
SCLK
N.C.
8
13
N.C.
INT1
9
12
CE
GND
10
11
SERMODE
DS1305
TSSOP (4.4mm)
TOP VIEW
19-5055; Rev 12/09