![](http://datasheet.mmic.net.cn/Maxim-Integrated-Products/DS1243Y-120_datasheet_100934/DS1243Y-120_9.png)
DS1243Y
9 of 14
PHANTOM CLOCK AC ELECTRICAL CHARACTERISTICS
(VCC = 4.5V to 5.5V, TA = 0°C to +70°C.)
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
NOTES
Read Cycle Time
tRC
120
ns
CE
Access Time
tCO
100
ns
OE
Access Time
tOE
100
ns
CE
to Output Low-Z
tCOE
10
ns
OE
to Output Low-Z
tOEE
10
ns
CE
to Output High-Z
tOD
40
ns
5
OE
to Output High-Z
tODO
40
ns
5
Read Recovery
tRR
20
ns
Write Cycle Time
tWC
120
ns
Write Pulse Width
tWP
100
ns
Write Recovery
tWR
20
ns
10
Data Setup Time
tDS
40
ns
11
Data Hold Time
tDH
10
ns
11
CE
Pulse Width
tCW
100
ns
RESET
Pulse Width
tRST
200
ns
CE
High to Power-Fail
tPF
0
ns
POWER-DOWN/POWER-UP TIMING
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
NOTES
CE
at VIH before Power-Down
tPD
0
s
VCC Slew from 4.5V to 0V ( CE at VIH)
tF
300
s
VCC Slew from 0V to 4.5V ( CE at VIH)
tR
0
s
CE
at VIH after Power-Up
tREC
2
ms
(TA = +25°C)
PARAMETER
SYMBOL
MIN
TYP
MAX UNITS NOTES
Expected Data-Retention Time
tDR
10
years
9
WARNING: Under no circumstances are negative undershoots, of any amplitude, allowed when
device is in battery-backup mode.