Datasheet

Typical Operating Characteristics
(V
CC
= +3.3V, T
A
= +25°C, unless otherwise noted.)
I
BAT
vs. TEMPERATURE
V
BAT
= 3.0V
DS1318 toc01
TEMPERATURE (°C)
SUPPLY CURRENT (nA)
6040200-20
650
700
750
800
850
600
-40 80
V
CC
= 0
I
BAT
vs. V
BAT
DS1318 toc02
V
BACKUP
(V)
SUPPLY CURRENT (nA)
3.53.12.72.31.9
550
600
650
700
750
800
850
500
1.5
V
CC
= 0
OSCILLATOR FREQUENCY vs. VOLTAGE
DS1318 toc03
INPUT VOLTAGE (V)
FREQUENCY (Hz)
3.53.02.5
32768.10
32768.20
32768.30
32768.40
32768.50
32768.45
32768.35
32768.25
32768.15
32768.05
32768.00
2.0 4.0
DS1318
Parallel-Interface Elapsed Time Counter
6 _____________________________________________________________________
AC TEST CONDITIONS
PARAMETER TEST CONDITION
Input Pulse Levels 0 to 2.7V
Output Load Including Scope and Jig 25pF + 1TTL Gate
Input and Output Timing Measurement Reference Levels V
CC
/ 2
Input-Pulse Rise and Fall Times 4ns
WARNING:
Under no circumstances are negative undershoots, of any amplitude, allowed when device is in write protection.
Note 2: Limits at -40°C are guaranteed by design and not production tested.
Note 3: All voltages are referenced to ground.
Note 4: OE, CE, WE, EXT, and A3–A0.
Note 5: DQ7–DQ0, SQW, and IRQ, when the outputs are high impedance.
Note 6: Outputs open.
Note 7: Specified with parallel bus inactive.
Note 8: Measured with a 32,768kHz crystal attached to the X1 and X2 pins.
Note 9: The parameter t
OSF
is the period of time that the oscillator must be stopped for the OSF flag to be set over the voltage
range of 0V ≤ V
CC
≤ V
CC(MAX)
and 1.3V ≤ V
BAT
≤ 3.7V.
Note 10: This delay applies only if the oscillator is enabled and running. If the ENOSC bit is 0, t
REC
is disabled, and the device is
immediately accessible. If CE and OE are low on power-up, the DQ outputs are active. Valid data out is not available until
after t
REC
.