DS1220 Dallas, DS1220 Datasheet - Page 7

• Manufacturer Part Number: DS1220
• Description: 16k Nonvolatile SRAM
• Manufacturer: Dallas

POWER-DOWN/POWER-UP CONDITION
SEE NOTE 11
POWER-DOWN/POWER-UP TIMING
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
3. t
4. t
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
PARAMETER
V
V
PARAMETER
Expected Data Retention Time
CE
CE at V
CC
CC
going low to the earlier of CE or WE going high.
buffers remain in a high-impedance state during this period.
WP
DS
at
slew from V
slew from 0
is measured from the earlier of CE or WE going high.
is specified as the logical AND of CE and WE . t
V
IH
IH
IH
before Power-Down
after Power-Up
or V
V
IL
TP
to V
. If OE = V
to 0v
TP
IH
during write cycle, the output buffers remain in a high-impedance state.
SYMBOL MIN TYP MAX UNITS
SYMBOL MIN TYP MAX UNITS
7 of 9
t
t
t
REC
t
PD
t
DR
F
R
WP
300
300
is measured from the latter of CE or CE
10
0
2
125
(t
A
years
: See Note 10)
ms
s
s
s
(T
DS1220AB/AD
A
NOTES
NOTES
=25°C)
11
9