EtronTech
EM68C08CWAE
- tJIT(per), tJIT(per,lck)
tJIT(per) is defined as the largest deviation of any single tCK from tCK(avg).
tJIT(per) = Min/max of {tCKi- tCK(avg) where i=1 to 200}
tJIT(per) defines the single period jitter when the DLL is already locked.
tJIT(per,lck) uses the same definition for single period jitter, during the DLL locking period only.
tJIT(per) and tJIT(per,lck) are not guaranteed through final production testing.
- tJIT(cc), tJIT(cc,lck)
tJIT(cc) is defined as the difference in clock period between two consecutive clock cycles:
tJIT(cc) = Max of |tCKi+1 – tCKi
|
tJIT(cc) defines the cycle to cycle jitter when the DLL is already locked.
tJIT(cc,lck) uses the same definition for cycle to cycle jitter, during the DLL locking period only.
tJIT(cc) and tJIT(cc,lck) are not guaranteed through final production testing.
- tERR(2per), tERR (3per), tERR (4per), tERR (5per), tERR (6-10per) and tERR (11-50per)
tERR is defined as the cumulative error across multiple consecutive cycles from tCK(avg).
⎧
⎪
⎪
⎪
n=2
n=3
n=4
n=5
for
for
for
for
2per
3per
4per
5per
(
(
(
(
)
)
)
)
tERR
tERR
tERR
tERR
tERR
tERR
i +N−1
⎡
⎤
⎥
⎦
⎪
⎨
nper =
− N ×
(
avg
CK
where
(
)
(
)
)
⎢ ∑
tERR
t
t
CKj
j =1
⎣
⎪
⎪
⎪
⎪
6 ≤ n ≤ 10 for
6 −10per
)
11≤ n ≤ 50 for
11− 50per
(
)
⎩
NOTE 34: These parameters are specified per their average values, however it is understood that the following
relationship between the average timing and the absolute instantaneous timing holds at all times. (Min
andmax of SPEC values are to be used for calculations in the table below.)
Table 31. Absolute clock period average values
Parameter
Symbol
Min.
Max.
Units
Absolute clock period
tCK (abs)
tCK(avg),min + tJIT(per),min
tCK(avg),max + tJIT(per),max
ps
Absolute clock HIGH pulse width tCH (abs) tCH(avg),min * tCK(avg),min + tCH(avg),max * tCK(avg),max + ps
tJIT(duty),min tJIT(duty),max
tCL (abs) tCL(avg),min * tCK(avg),min + tCL(avg), max * tCK(avg),max
tJIT(duty),min + tJIT(duty), max
Absolute clock LOW pulse width
ps
NOTE 35:tHP is the minimum of the absolute half period of the actual input clock. tHP is an input parameter but not an
input specification parameter. It is used in conjunction with tQHS to derive the DRAM output timing tQH. The
value to be used for tQH calculation is determined by the following equation;
tHP = Min ( tCH(abs), tCL(abs) ),
where,
tCH(abs) is the minimum of the actual instantaneous clock HIGH time;
tCL(abs) is the minimum of the actual instantaneous clock LOW time;
NOTE 36: tQHS accounts for:
1) The pulse duration distortion of on-chip clock circuits, which represents how well the actual tHP at the input
is transferred to the output; and
2) The worst case push-out of DQS on one transition followed by the worst case pull-in of DQ on the next
transition, both of which are independent of each other, due to data pin skew, output pattern effects, and
p-channel to n-channel variation of the output drivers
Rev. 1.3
34
Oct. /2015
ETRON [ ETRON TECHNOLOGY, INC. ]
