MV78200 Datasheet, PDF (87/128 Pages) –

Electrical Specifications
9.6.6.2
SDRAM DDR2 400 MHz Clock Specifications
Table 44: SDRAM DDR2 400 MHz Clock Specifications
De s cr iption
Clock period jitter
Clock perior jitter during DLL locking period
Cycle to cycle clock period jitter
Cycle to cycle clock period jitter during DLL locking period
Cumulative error across 2 cycles
Cumulative error across 3 cycles
Cumulative error across 4 cycles
Cumulative error across 5 cycles
Cumulative error across n cycles, n=6...10, inclusive
Cumulative error across n cycles, n=11…50, inclusive
Duty cycle jitter
Absolute clock period
Absolute clock high pulse w idth
Absolute clock low pulse w idth
Sym bol
tJIT(per)
tJIT(per,lck)
tJIT(cc)
tJIT(cc,lck)
tERR(2per)
tERR(3per)
tERR(4per)
tERR(5per)
tERR(6-10per)
tERR(11-50per)
tJIT(duty)
tCK(abs)
tCH(abs)
tCL(abs)
M in
M ax
-100
100
-80
80
-200
200
-160
160
-150
150
-175
175
-200
200
-200
200
-300
300
-450
450
-100
100
See note 7
See note 8
See note 9
Units
ps
ps
ps
ps
ps
ps
ps
ps
ps
ps
ps
ps
ps
ps
Note s
1
2
3
4
5
5
5
5
5
5
6
7
8
9
Note s :
General comment: All timing values are defined on CLK / CLKn crossing point, unless otherw ise specified.
1. tJIT(per) is def ined as the largest deviation of any single tCK f rom tCK(avg).
tJIT(per) = Min/max of {tCKi- tCK(avg) w here i=1 to 200}.
tJIT(per) defines the single period jitter w hen the DLL is already locked.
2. tJIT(per,lck) uses the same definition for single period jitter, during the DLL locking period only.
3. tJIT(cc) is defined as the difference in clock period betw een tw o consecutive clock cycles: tJIT(cc) = Max of |tCKi+1 – tCKi|.
tJIT(cc) defines the cycle to cycle jitter w hen the DLL is already locked.
4. tJIT(cc,lck) uses the same definition for cycle to cycle jitter, during the DLL locking period only.
5. tERR(nper) is def ined as the cumulative error across multiple consecutive cycles f rom tCK(avg).
Ref er to JEDEC Standard No. 79-2 (DDR2 SDRAM Specif ication) f or more inf ormation.
6. tJIT(duty) is defined as the cumulative set of tCH jitter and tCL jitter. tCH jitter is the largest deviation of
any single tCH f rom tCH(avg). tCL jitter is the largest deviation of any single tCL f rom tCL(avg).
tJIT(duty) = Min/max of {tJIT(CH), tJIT(CL)} w here,
tJIT(CH) = {tCHi- tCH(avg) w here i=1 to 200}; tJIT(CL) = {tCLi- tCL(avg) w here i=1 to 200}.
7. tCK(abs),min = tCK(avg),min + tJIT(per),min; tCK(abs),max = tCK(avg),max + tJIT(per),max.
8. tCH(abs),min = tCH(avg),min x tCK(avg),min + tJIT(duty),min; tCH(abs),max = tCH(avg),max x tCK(avg),max + tJIT(duty),max.
9. tCL(abs),min = tCL(avg),min x tCK(avg),min + tJIT(duty),min; tCL(abs),max = tCL(avg),max x tCK(avg),max + tJIT(duty),max.
Copyright © 2008 Marvell
December 6, 2008, Preliminary
Document Classification: Proprietary Information
MV-S104671-U0 Rev. C
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