DS1315
Phantom Time Chip
www.dalsemi.com
www.maxim-ic.com
DESCRIPTION
FEATURES
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.
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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% VCC operating range
+3.3 volt or +5 volt operation
Industrial (–45°C to +85°C) operating
temperature ranges available
Drop in replacement for DS1215
PIN DESCRIPTION
PIN CONFIGURATIONS
X1, X2
WE
X1
1
16
VCC1
X2
2
15
VCC0
WE
3
14
BAT2
BAT1
4
13
RST
GND
5
12
OE
D
6
11
CEI
Q
7
10
CEO
GND
8
9
BAT1
GND
D
Q
ROM/ RAM
ROM/RAM
16-Pin DIP (300-mil)
CEO
CEI
OE
RST
BAT2
VCC0
VCC1
- 32.768 kHz Crystal Connection
- Write Enable
- Battery 1 Input
- Ground
- Data Input
- Data Output
- ROM/RAM Mode Select
- Chip Enable Output
- Chip Enable Input
- Output Enable
- Reset
- Battery 2 Input
- Switched Supply Output
- Power Supply Input
Pin Configurations continued at end of data sheet.
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.
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REV: 040203
