Datasheet

DS1220AB/AD
6 of 8
POWER-DOWN/POWER-UP CONDITION
SEE NOTE 11
POWER-DOWN/POWER-UP TIMING (T
A
: See Note 10)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
V
CC
Fail Detect to
CE
and
WE
Inactive
t
PD
1.5
µs
11
V
CC
slew from V
TP
to 0V t
F
300
µs
V
CC
slew from 0V to V
TP
t
R
300
µs
V
CC
Valid to
CE
and
WE
Inactive
t
PU
2 ms
V
CC
Valid to End of Write Protection t
REC
125 ms
(T
A
= +25°C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Expected Data Retention Time
t
DR
10
years
9
WARNING:
Under no circumstances are negative undershoots, of any amplitude, allowed when device is in the
battery backup mode.
NOTES:
1.
WE
is high for a read cycle.
2.
OE
= V
IH
or V
IL
. If
OE
= V
IH
during write cycle, the output buffers remain in a high-impedance state.
3. t
WP
is specified as the logical AND of
CE
and
WE
. t
WP
is measured from the latter of
CE
or
CE
going low to the earlier of
CE
or
WE
going high.
4. t
DS
is measured from the earlier of
CE
or
WE
going high.
5. These parameters are sampled with a 5 pF load and are not 100% tested.
6. If the
CE
low transition occurs simultaneously with or later than the
WE
low transition, the output
buffers remain in a high-impedance state during this period.
7. If the
CE
high transition occurs prior to or simultaneously with the
WE
high transition, the output
buffers remain in a high-impedance state during this period.