17
V55C3256164VG Rev. 1.0 September 2008
ProMOS TECHNOLOGIES
V55C3256164VG
Notes for AC Parameters:
1.
For proper power-up see the operation section of this data sheet.
2.
AC timing tests have VIL = 0.8V and VIH = 2.0V with the timing referenced to the 1.4 V crossover point. The transition
time is measured between VIH and VIL. All AC measurements assume tT = 1ns with the AC output load circuit shown
in Figure 1.
3.
If clock rising time is longer than 1 ns, a time (tT/2 – 0.5) ns has to be added to this parameter.
4.
If tT is longer than 1 ns, a time (tT – 1) ns has to be added to this parameter.
5.
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.
6.
Referenced to the time which the output achieves the open circuit condition, not to output voltage levels.
7. For TA = -40 to 105o C (H grade) / -40 to 125o C (Extended grade).
8. These parameter depend on output loading. Specified values are obtained with output open.
9. H grade / Extended grade does not guarantee Self-refresh current (ICC6).
Read Cycle
24
tOH
Data Out Hold Time
2.5
–
3
–
3
–
ns
2
25
tLZ
Data Out to Low Impedance Time
1
–
1
–
1
–
ns
26
tHZ
Data Out to High Impedance Time
3
6
3
7
3
7
ns
6
27
tDQZ
DQM Data Out Disable Latency
–
2
–
2
–
2
CLK
Write Cycle
28
tWR
Write Recovery Time for Auto precharge
2
–
2
–
2
–
CLK
29
tDQW
DQM Write Mask Latency
0
–
0
–
0
–
CLK
#
Symbol
Parameter
Limit Values
Unit
Note
-6
-7PC
-7
Min.
Max.
Min.
Max.
Min.
Max.
1.4V
tIS
tIH
tAC
tLZ
tOH
tHZ
CLK
COMMAND
OUTPUT
50 pF
I/O
Z=50 Ohm
+ 1.4 V
50 Ohm
VIH
VIL
tT
Figure 1.
tCK