Datasheet

DS1644/DS1644P
8 of 14
AC ELECTRICAL CHARACTERISTICS (Over the Operating Range)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Read Cycle Time t
RC
120 ns
Address Access Time t
AA
120 ns
CE Access Time
t
CEA
120 ns
CE Data Off Time
t
CEZ
40 ns
Output Enable Access Time t
OEA
100 ns
Output Enable Data Off Time t
OEZ
40 ns
Output Enable to DQ Low-Z t
OEL
5 ns
CE to DQ Low-Z
t
CEL
5 ns
Output Hold from Address t
OH
5 ns
Write Cycle Time t
WC
120 ns
Address Setup Time t
AS
0 ns
CE
Pulse Width
t
CEW
100 ns
t
AH1
5 ns 5
Address Hold from End of Write
t
AH2
30 ns 6
Write Pulse Width t
WEW
75 ns
WE
Data Off Time
t
WEZ
40 ns
WE or CE Inactive Time
t
WR
10 ns
Data Setup Time t
DS
85 ns
t
DH1
0 ns 5
Data Hold Time High
t
DH2
15 ns 6
AC TEST CONDITIONS
Input Levels: 0V to 3V
Transition Times: 5 ns
CAPACITANCE (T
A
= +25C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Capacitance on all pins (except DQ) C
I
7 pF
Capacitance on DQ pins C
DQ
10 pF
AC ELECTRICAL CHARACTERISTICS
(POWER-UP/DOWN TIMING) (Over the Operating Range)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
CE or WE at V
IH
before Power Down
t
PD
0
s
V
PF
(Max) to V
PF
(Min) V
CC
Fall Time t
F
300
s
V
PF
(Min) to V
SO
V
CC
Fall Time t
FB
10
s
V
SO
to V
PF
(Min) V
CC
Rise Time t
RB
1
s
V
PF
(Min) to V
PF
(Max) V
CC
Rise Time t
R
0
s
Power-Up t
REC
15 35 ms
Expected Data Retention Time
(Oscillator On)
t
DR
10 years 4