鈥?/div>
Optional industrial temperature range 鈥?0擄C to +85擄C
(IND)
16鈥揚IN SOIC (300 MIL)
PIN DESCRIPTION
X1, X2
鈥?32.768 KHz Crystal Connections
WE
鈥?Write Enable
BAT1
鈥?Battery 1 Input
GND
鈥?Ground
D
鈥?Data In
Q
鈥?Data Out
鈥?ROM/RAM Select
ROM/RAM
鈥?Chip Enable Out
CEO
CEI
鈥?Chip Enable Input
OE
鈥?Output Enable
RST
鈥?Reset
BAT2
鈥?Battery 2 Input
鈥?Switched Supply Output
V
CCO
鈥?+5 VDC Input
V
CCI
NOTE: Both pins 5 and 8 must be grounded.
DESCRIPTION
The DS1215 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 hun-
dredths 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 correction for leap year every four years.
The watch operates in one of two formats: a 12鈥揾our
mode with an AM/PM indicator or a 24鈥揾our mode. The
nonvolatile controller supplies all the necessary support
circuitry to convert a CMOS RAM to a nonvolatile
memory. The DS1215 can be interfaced with either
RAM or ROM without leaving gaps in memory.
ORDERING INFORMATION
DS1215
DS1215S
DS1215N
DS1215SN
16鈥損in DIP
16鈥損in SOIC
16鈥損in DIP (IND)
16鈥損in SOIC (IND)
ECopyright
1997 by Dallas Semiconductor Corporation.
All Rights Reserved. For important information regarding
patents and other intellectual property rights, please refer to
Dallas Semiconductor data books.
032697 1/15