
DS1557 4Meg, Nonvolatile, Y2K-Compliant Timekeeping RAM
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POWER-UP/DOWN CHARACTERISTICS—3.3V
(VCC = 3.3V ±10%, TA = Over the Operating Range.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
CE or WE at V
IH, Before
Power-Down
tPD
0
s
VCC Fall Time: VPF(MAX) to VPF(MIN)
tF
300
s
VCC Rise Time: VPF(MIN) to VPF(MAX)
tR
0
s
VPF to RST High
tREC
40
200
ms
Expected Data-Retention Time
(Oscillator On)
tDR
(Note 6)
10
years
Figure 9. Power-Up/Down Waveform Timing—3.3V Device
CAPACITANCE
(TA = +25°C)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Capacitance on All Input Pins
CIN
(Note 1)
14
pF
Capacitance on
IRQ/FT, RST,
and DQ Pins
CIO
(Note 1)
10
pF