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REV: 090407
Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device
may be simultaneously available through various sales channels. For information about device errata, click here: www.maxim-ic.com/errata.
DESCRIPTION
The
DS1315
Phantom
Time
Chip
is
a
combination of a CMOS timekeeper and a
nonvolatile memory controller. In the absence of
power,
an
external
battery
maintains
the
timekeeping operation and provides power for a
CMOS static RAM. The watch keeps track of
hundredths of seconds, seconds, minutes, hours,
day, date, month, and year information. The last
day of the month is automatically adjusted for
months with less than 31 days, including leap
year correction. The watch operates in one of two
formats: a 12-hour mode with an AM/PM
indicator or a 24-hour mode. The nonvolatile
controller supplies all the necessary support
circuitry to convert a CMOS RAM to a
nonvolatile
memory.
The
DS1315
can
be
interfaced with either RAM or ROM without
leaving gaps in memory.
PIN CONFIGURATIONS
Pin Configurations continued at end of data sheet.
FEATURES
Real-Time Clock Keeps Track of Hundredths
of Seconds, Seconds, Minutes, Hours, Days,
Date of the Month, Months, and Years
Adjusts for Months with Fewer than 31 Days
Automatic Leap Year Correction Valid Up to
2100
No Address Space Required to Communicate
with RTC
Provides Nonvolatile Controller Functions for
Battery Backup of SRAM
Supports Redundant Battery Attachment for
High-Reliability Applications
Full ±10% V
CC Operating Range
+3.3V or +5V Operation
Industrial (–45°C to +85°C) Operating
Temperature Ranges Available
Drop-In Replacement for DS1215
PIN DESCRIPTION
X1, X2
- 32.768 kHz Crystal Connection
WE
- Write Enable
BAT1
- Battery 1 Input
GND
- Ground
D
- Data Input
Q
- Data Output
ROM/ RAM
- ROM/RAM Mode Select
CEO
- Chip Enable Output
CEI
- Chip Enable Input
OE
- Output Enable
RST
- Reset
BAT2
- Battery 2 Input
VCC0
- Switched Supply Output
VCC1
- Power Supply Input
www.dalsemi.com
DS1315
Phantom Time Chip
www.maxim-ic.com
DIP (300 mils)
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
VCC1
VCC0
BAT2
RST
OE
CEI
CEO
ROM/RAM
X1
X2
WE
BAT1
GND
D
Q
GND
DS1315