DS1216 Datasheet, PDF (1/15 Pages) Dallas Semiconductor – SmartWatch RAM DS1216B/C/D/H SmartWatch ROM DS1216E/F

19-6075; Rev 11/11
DS1216
SmartWatch RAM (DS1216B/C/D/H);
SmartWatch ROM (DS1216E/F)
GENERAL DESCRIPTION
The DS1216 SmartWatch RAM and SmartWatch
ROM sockets are 600-mil-wide DIP sockets with a
built-in CMOS watch function, an NV RAM
controller circuit, and an embedded lithium energy
source. The sockets provide an NV RAM solution
for memory sized from 2K x 8 to 512K x 8 with
package sizes from 26 pins to 32 pins. When a
socket is mated with a CMOS SRAM, it provides a
complete solution to problems associated with
memory volatility and uses a common energy
source to maintain time and date. The SmartWatch
ROM sockets use the embedded lithium source to
maintain the time and date only. A key feature of
the SmartWatch is that the watch function remains
transparent to the RAM. The SmartWatch monitors
V_CC for an out-of-tolerance condition. When such a
condition occurs, an internal lithium energy source
is automatically switched on and write protection
is unconditionally enabled to prevent loss of watch
and RAM data.
TYPICAL OPERATING CIRCUIT
FEATURES
 Keeps Track of Hundredths of Seconds,
Seconds, Minutes, Hours, Days, Date of the
Month, Months, and Years
 Converts Standard 2K x 8 Up to 512K x 8
CMOS Static RAMs into Nonvolatile Memory
 Embedded Lithium Energy Cell Maintains
Watch Information and Retains RAM Data
 Watch Function is Transparent to RAM
Operation
 Automatic Leap Year Compensation Valid Up
to 2100
 Lithium Energy Source is Electrically
Disconnected to Retain Freshness Until Power
is Applied for the First Time
 Proven Gas-Tight Socket Contacts
 Full ±10% Operating Range
 Accuracy Better Than ±1 Minute/Month
at +25°C
ORDERING INFORMATION
PART
DS1216B
DS1216C
DS1216D
DS1216E
DS1216F
DS1216H
TEMP RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
PIN-PACKAGE
28 SmartWatch Socket
28 SmartWatch Socket
32 SmartWatch Socket
28 SmartWatch Socket
32 SmartWatch Socket
32 SmartWatch Socket
(See Figure 2 for letter suffix marking identification.)
Selector Guide appears on page 2.
1 of 15