Floorplan Guidelines

2.Floorplan

There will be certain guidelines to follow ,to get a good floorplan without congestion and timing issues later in the design
a)place the macros at core area
b)place the io’s to core area
c)use fly lines or flight lines
d)if macros to io connections are there ,then place the macro near the io ports
e)macros to macros connections ,place near by
f) avoid criss cross placement
g) place the macros with minimum spacing between macros
h) add blockages where to avoid the congestion
i) add halos to to every macros ,to avoid cells placing near by(congestion)
j) avoid placing macros in the middle(routing issues or ir drop may occur (buffers)due to blockages of macros)
k) don’t place the macros at the Io’s ,which may block them
l) place macros the macros by allowing some place to the io ‘s routing.
m) avoid notches
n) place with hierarchical analysis
o) provide uniform std cell area.
p) add preplace cells(end cap cells ,tap cells,decap cells)


PowerPlan :

The VDD and VSS are added for the Power rings and stripes which supply  power to the cells placed in the core area .
Try to place the stripes and with equal distance from each stripes,to better supply.

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