APEX 20K Programmable Logic Device Family Data Sheet
Figure 11 shows the intersection of a row and column interconnect, and
how these forms of interconnects and LEs drive each other.
Figure 11. Driving the FastTrack Interconnect
Row Interconnect
MegaLAB Interconnect
Column
Interconnect
LE
Local
Interconnect
APEX 20KE devices include an enhanced interconnect structure for faster
routing of input signals with high fan-out. Column I/ O pins can drive the
FastRow interconnect, which routes signals directly into the local
interconnect without having to drive through the MegaLAB interconnect.
FastRow lines traverse two MegaLAB structures. Also, these pins can
drive the local interconnect directly for fast setup times. On EP20K300E
and larger devices, the FastRow interconnect drives the two MegaLABs in
the top left corner and the two MegaLABs in the bottom right corner. On
EP20K200E and smaller devices, FastRow interconnect drives the two
MegaLABs on the top and the two MegaLABs on the bottom of the device.
On all devices, the FastRow interconnect drives all local interconnect in
the appropriate MegaLABs except the interconnect areas on the far left
and far right of the MegaLAB. Pins using the FastRow interconnect
achieve a faster set-up time, as the signal does not need to use a MegaLab
interconnect line to reach the destination LE. Figure 12 shows the FastRow
interconnect.
Altera Corporation
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ETC [ ETC ]
