Lattice Semiconductor
ispMACH 4000V/B/C/Z Family Data Sheet
Timing Model
The task of determining the timing through the ispMACH 4000 family, like any CPLD, is relatively simple. The timing
model provided in Figure 11 shows the specific delay paths. Once the implementation of a given function is deter-
mined either conceptually or from the software report file, the delay path of the function can easily be determined
from the timing model. The Lattice design tools report the timing delays based on the same timing model for a par-
ticular design. Note that the internal timing parameters are given for reference only, and are not tested. The exter-
nal timing parameters are tested and guaranteed for every device. For more information on the timing model and
usage, please refer to Technical Note TN1004: ispMACH 4000 Timing Model Design and Usage Guidelines.
Figure 11. ispMACH 4000 Timing Model
Routing/GLB Delays
From
Feedback
tPDb
tPDi
Feedback
Out
tFBK
tROUTE
tBLA
tMCELL
tEXP
tIN
tBUF
tIOO
tEN
DATA
IN
tORP
tIOI
Q
tINREG
tINDIO
tDIS
tGCLK_IN
tIOI
In/Out
Delays
SCLK
tPTCLK
tBCLK
C.E.
S/R
tPTSR
tBSR
Register/Latch
Delays
MC Reg.
tGPTOE
tPTOE
Control
Delays
tGOE
tIOI
OE
In/Out
Delays
Note: Italicized items are optional delay adders.
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