Rainbow Electronics DS1244Y - Manual (Page 12)

DS1244/DS1244P
12 of 19
POWER-DOWN/POWER-UP TIMING Over the operating range (3.3V)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
CE at V
IH
before Power-Down
t
PD
0 ms
V
CC
Slew from V
PF(MAX)
to
V
PF(MIN)
( CE at V
IH
)
t
F
300 ms
V
CC
Slew from V
PF(MAX)
to
V
PF(MIN)
( CE at V
IH
)
t
R
0 ms
CE at V
IH
after Power-Up
t
REC
1.5 2.5 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 battery-backup mode.