DS1315 Datasheet, PDF (1/21 Pages) Dallas Semiconductor – Phantom Time Chip

19-6080; Rev 11/11
www.dalsemi.com
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 fewer 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
X1 ¹
16
V_CC1
X2 ² _DS1315 ^{15 V}CC0
WE ³
14 BAT2
BAT1 4
13 RST
GND 5
12 OE
D6
11 CEI
Q7
10 CEO
GND ⁸
9 ROM/RAM
PDIP (300 mils)
Pin Configurations continued at end of data sheet.
DS1315
Phantom Time Chip
FEATURES
 Real-Time Clock Keeps Track of Hundredths
of Seconds, Seconds, Minutes, Hours, Days,
Date of the Month, Months, and Years
 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 (-40°C to +85°C) Operating
Temperature Ranges Available
PIN DESCRIPTION
X1, X2
- 32.768kHz Crystal Connection
WE
BAT1
GND
D
Q
- Write Enable
- Battery 1 Input
- Ground
- Data Input
- Data Output
ROM/ RAM - ROM/RAM Mode Select
CEO
- Chip Enable Output
CEI
- Chip Enable Input
OE
- Output Enable
RST
BAT2
V_CC0
V_CC1
- Reset
- Battery 2 Input
- Switched Supply Output
- Power Supply Input
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