EtronTech
EM68C08CWAE
Table 30. Input clock jitter spec parameter
-18
-25
-3
Parameter
Clock period jitter
Symbol
Units Notes
Min.
Max.
90
Min.
-100
-80
Max.
100
80
Min.
-125
-100
-250
-200
-175
-225
-250
-250
-350
-450
-125
Max.
125
100
250
200
175
225
250
250
350
450
125
tJIT (per)
-90
ps
ps
ps
ps
ps
ps
ps
ps
ps
ps
ps
33
33
33
33
33
33
33
33
33
33
33
Clock period jitter during DLL locking
period
Cycle to cycle clock period jitter
tJIT (per,lck) -80
JIT (cc) -180
80
t
180
160
132
157
175
188
250
425
75
-200
-160
-150
-175
-200
-200
-300
-450
-100
200
160
150
175
200
200
300
450
100
Cycle to cycle clock period jitter
during DLL locking period
Cumulative error across 2 cycles
tJIT (cc,lck) -160
tERR (2per) -132
Cumulative error across 3 cycles
Cumulative error across 4 cycles
Cumulative error across 5 cycles
t
t
t
ERR (3per) -157
ERR (4per) -175
ERR (5per) -188
Cumulative error across n cycles,
n=6...10, inclusive
Cumulative error across n cycles,
n=11...50, inclusive
tERR (6-
-250
10per)
tERR (11-
50per)
-425
Duty cycle jitter
tJIT (duty)
-75
Definitions:
- tCK(avg)
tCK(avg) is calculated as the average clock period across any consecutive 200 cycle window.
N
⎡
⎤
⎥
⎦
avg =
/N
where N=200
(
)
⎢∑
tCK
t
CKj
j =1
⎣
- tCH(avg) and tCL(avg)
tCH(avg) is defined as the average HIGH pulse width, as calculated across any consecutive 200 HIGH pulses.
N
⎡
⎤
⎥
⎦
avg =
/ N ×
(
avg
CK
where N=200
(
)
(
)
)
⎢∑
tCH
t
t
CHj
j =1
⎣
tCL(avg) is defined as the average LOW pulse width, as calculated across any consecutive 200 LOW pulses.
N
⎡
⎤
⎥
⎦
avg =
/ N ×
(
avg
CK
where N=200
(
)
(
)
)
⎢∑
tCL
t
t
CLj
j =1
⎣
tJIT (duty) is defined as the cumulative set of tCH jitter and tCL jitter. tCH jitter is the largest deviation of any single tCH
from tCH(avg). tCL jitter is the largest deviation of any single tCL from tCL(avg).
- tJIT(duty) = Min/max of {tJIT(CH), tJIT(CL)}
where,
tJIT(CH) = {tCHi- tCH(avg) where i=1 to 200}
tJIT(CL) = {tCLi- tCL(avg) where i=1 to 200}
Rev. 1.3
33
Oct. /2015
ETRON [ ETRON TECHNOLOGY, INC. ]
