V54C3256164VBUC/T
AC Characteristics (Cont’d)
Limit Values
-7PC -7
-8PC
-6
#
Symbol Parameter
Min. Max. Min. Max. Min. Max. Min. Max. Unit Note
Read Cycle
21
22
23
24
tOH
tLZ
Data Out Hold Time
3
1
3
–
–
–
6
2
3
1
3
–
–
–
7
2
3
1
3
–
–
–
7
2
3
0
3
–
–
–
8
2
ns
ns
2
7
Data Out to Low Impedance Time
Data Out to High Impedance Time
DQM Data Out Disable Latency
tHZ
ns
tDQZ
CLK
Write Cycle
25
26
tWR
Write Recovery Time
2
0
–
–
2
0
–
–
2
0
–
–
2
0
–
–
CLK
CLK
tDQW
DQM Write Mask Latency
Notes for AC Parameters:
1. For proper power-up see the operation section of this data sheet.
2. AC timing tests have V = 0.8V and V = 2.0V with the timing referenced to the 1.4 V crossover point. The transition
IL
IH
time is measured between V and V . All AC measurements assume t = 1ns with the AC output load circuit shown
IH
IL
T
in Figure 1.
tCK
VIH
VIL
CLK
+ 1.4 V
t
T
tCS
tCH
50 Ohm
1.4V
COMMAND
Z=50 Ohm
I/O
tAC
tAC
tLZ
50 pF
tOH
1.4V
OUTPUT
tHZ
Figure 1.
4. If clock rising time is longer than 1 ns, a time (t /2 – 0.5) ns has to be added to this parameter.
T
5. If t is longer than 1 ns, a time (t – 1) ns has to be added to this parameter.
T
T
6. These parameter account for the number of clock cycle and depend on the operating frequency of the clock, as
follows:
the number of clock cycle = specified value of timing period (counted in fractions as a whole number)
Self Refresh Exit is a synchronous operation and begins on the 2nd positive clock edge after CKE returns high.
Self Refresh Exit is not complete until a time period equal to tRC is satisfied once the Self Refresh Exit command
is registered.
7. Referenced to the time which the output achieves the open circuit condition, not to output voltage levels
V54C3256164VBUC/T Rev. 1.1 February 2003
13
MOSEL [ MOSEL VITELIC, CORP ]
