Rainbow Electronics DS1251Y - Manual (Page 11)

DS1251/DS1251P
11 of 22
PHANTOM CLOCK AC ELECTRICAL CHARACTERISTICS
Over the operating range (5V)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Read Cycle Time t
RC
65 ns
CE Access Time t
CO
55 ns
OE Access Time t
OE
55 ns
CE to Output Low-Z t
COE
5 ns
OE to Output Low-Z t
OEE
5 ns
CE to Output High-Z t
OD
25 ns 5
OE to Output High-Z t
ODO
25 ns 5
Read Recovery t
RR
10 ns
Write Cycle Time t
WC
65 ns
Write Pulse Width t
WP
55 ns 3
Write Recovery t
WR
10 ns 10
Data Setup Time t
DS
30 ns 4
Data Hold Time t
DH
0 ns 4
CE Pulse Width t
CW
60 ns
RESET Pulse Width t
RST
65 ns
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
PF
)
t
F
300 ms
V
CC
Slew from V
PF(min)
to V
SO
t
FB
10 ms
V
CC
Slew from V
PF(max)
to
V
PF(min)
( CE at V
PF
)
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.