DS1245 DALLAS [Dallas Semiconductor], DS1245 Datasheet - Page 7

• Manufacturer Part Number: DS1245
• Description: 3.3V 1024k Nonvolatile SRAM
• Manufacturer: DALLAS [Dallas Semiconductor]

POWER-DOWN/POWER-UP TIMING
WARNING:
Under no circumstance are negative undershoots, of any amplitude, allowed when device is in battery
backup mode.
NOTES:
1.
2.
3. t
4. t
5. These parameters are sampled with a 5 pF load and are not 100% tested.
6. If the
7. If the
8. If
9. Each DS1245W has a built-in switch that disconnects the lithium source until V
10. All AC and DC electrical characteristics are valid over the full operating temperature range. For
11. In a power-down condition the voltage on any pin may not exceed the voltage on V
12. t
13. t
PARAMETER
V
V
V
V
V
PARAMETER
Expected Data Retention Time
CC
CC
CC
CC
CC
going low to the earlier of
buffers remain in a high impedance state during this period.
buffers remain in high impedance state during this period.
the output buffers remain in a high impedance state during this period.
the user. The expected t
time power is first applied by the user.
commercial products, this range is 0 C to 70 C. For industrial products (IND), this range is -40 C to
+85 C.
OE
WE
WP
DH
WR1
WR2
Fail Detect to
slew from V
slew from 0V to V
Valid to
Valid to End of Write Protection
WE
, t
is specified as the logical AND of
= V
is high for a Read Cycle.
and t
and t
DS
CE
CE
is low or the
are measured from the earlier of
IH
DH1
DH2
or V
low transition occurs simultaneously with or latter than the
high transition occurs prior to or simultaneously with the
CE
are measured from
are measured from
TP
and
IL
. If
CE
to 0V
WE
OE
and
TP
WE
Inactive
= V
DR
WE
low transition occurs prior to or simultaneously with the
CE
IH
is defined as accumulative time in the absence of V
Inactive
during write cycle, the output buffers remain in a high impedance state.
or
CE
WE
WE
going high.
going high.
going high.
SYMBOL
SYMBOL
CE
CE
t
t
t
t
REC
or
and
t
t
DR
PD
PU
R
F
7 of 11
WE
WE
going high.
. t
MIN
MIN
150
150
WP
10
is measured from the latter of
TYP
TYP
WE
WE
MAX
MAX
125
1.5
15
2
high transition, the output
low transition, the output
(t
CC
A
CC
UNITS
UNITS
: See Note 10)
CC
CE
years
is first applied by
ms
ms
ms
starting from the
.
s
s
low transition,
(t
CE
A
NOTES
=25 C)
NOTES
DS1245W
or
11
9
WE