Internet Data Sheet
HYB18T512[40/80/16]0B[C/F]
512-Mbit Double-Data-Rate-Two SDRAM
Symbol
Parameter
Description
Units
tERR.nPER
Cumulative error
across n cycles
t
ERR.2PER is defined as the cumulative error across n consecutive cycles ps
from tCK.AVG
:
i + n – 1
⎛
⎜
⎜
⎝
⎞
⎟
tERR(nper) =
tCKj – n × tCK(avg)
(3)
∑
⎟
⎠
j = i
where, i = 1 to 200 and
n = 3 for tERR.3PER
n = 4 for tERR.4PER
n = 5 for tERR.5PER
6 ≤ n ≤ 10 for tERR.6-10PER
11 ≤ n ≤ 50 for tERR.11-50PER
tCH.AVG
tCL.AVG
tJIT.DUTY
Average high-pulse
width
tCH.AVG is defined as the average high-pulse width, as calculated across tCK.AVG
any consecutive 200 high pulses:
N
⎛
⎜
⎜
⎝
⎞
⎟
1
.
----------------------------------------
tCH(avg) =
tCHj
(4)
∑
⎟
⎠
(N × tCK(avg))
j = 1
N = 200
Average low-pulse
width
t
CL.AVG is defined as the average low-pulse width, as calculated across any tCK.AVG
consecutive 200 low pulses:
N
⎛
⎜
⎜
⎝
⎞
⎟
1
(5)
.
----------------------------------------
tCL(avg) =
tCLj
∑
⎟
⎠
(N × tCK(avg))
j = 1
N = 200
Duty-cycle jitter
t
t
t
t
t
JIT.DUTY = Min/Max of {tJIT.CH , tJIT.CL}, where:
ps
JIT.CH is the largest deviation of any single tCH from tCH.AVG
JIT.CL is the largest deviation of any single tCL from tCL.AVG
JIT.CH = {tCHi - tCH.AVG × tCK.AVG} where i=1 to 200
JIT.CL = {tCLi - tCL.AVG × tCK.AVG} where i=1 to 200
Rev. 1.1, 2007-05
57
03292006-YBYM-WG0Z
QIMONDA [ QIMONDA AG ]
