Rainbow Electronics DS1248Y - Manual (Page 7)

DS1248Y
032697 7/12
PHANTOM CLOCK AC ELECTRICAL CHARACTERISTICS (0 ° C to 70 ° C; V
CC
= 4.5 to 5.5V)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Read Cycle Time t
RC
120 ns
CE Access Time t
CO
100 ns
OE Access Time t
OE
100 ns
CE to Output Low Z t
COE
10 ns
OE to Output Low Z t
OEE
10 ns
CE to Output High Z t
OD
40 ns 5
OE to Output High Z t
ODO
40 ns 5
Read Recovery t
RR
20 ns
Write Cycle Time t
WC
120 ns
Write Pulse Width t
WP
100 ns
Write Recovery t
WR
20 ns 10
Data Setup Time t
DS
40 ns 11
Data Hold Time t
DH
10 ns 11
CE Pulse Width t
CW
100 ns
RESET Pulse Width t
RST
200 ns
CE High to Power–Fail t
PF
0 ns
POWER-DOWN/POWER-UP TIMING
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
CE at V
IH
before Power–Down t
PD
0
µ
s
V
CC
Slew from 4.5V to 0V
(CE at V
IH
)
t
F
300
µ
s
V
CC
Slew from 0V to 4.5V
(CE at V
IH
)
t
R
0 µ s
CE at V
IH
after Power–Up t
REC
2 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.