how to add filler pad in soce?

[lightcloud]

add io filler

Hi,
How to add filler pad in soc encounter,and how to do the pad ring?
I search,but find I can add filler cell only for standard cell.

Thanks a lot!

 

[joe2moon]

如何 add io filler

Add I/O Filler cells,
encounter> addIoFiller -cell <io_filler cell_name> -prefix pfill

 

[aravind]

addfiller prefix

any one please tell
what is siginficance of filler cells?
why we r using filler cells?
what r type of filler cells?
what is difference in different filler cells?
if we r not using filler cells in chip what will happen?
thanks

 

[lightcloud]

encounter io filler

Thanks, I will try it.

 

[Narasaiah]

add fillers soc encounter

what is siginficance of filler cells?
ans : filler cells will reduce power and ground bounces.
there is continues connection between power and ground rails and wel(n or p ) .
why we r using filler cells?
what r type of filler cells?
ans : fillers cell differ in size only.
what is difference in different filler cells?

if we r not using filler cells in chip what will happen?
ans : some times there will be some DRC errors like minimum spacing violations

If iam wrong please let me know

 

[appala.pradeep]

not connect pad io encounter filler

Yes, you are correct
adding filler cells will also decrease fabrication compleities such as mask

 

[sowmya005]

filler cells

Filler cells for different vth will be available,
The filler cells help for satisfying the continuity of vdd, gnd etc. and in addition provide substrate biasing.
The filler cells list is to be provided with the Largest one first.
If ur design is multi vt, u need to use the corresponding filler cells.
U cannot place a filler cell in between cells of different vth.

 

[sowmya005]

how to add filler

can u tell me whats the need of io filler cells ? what is the need ? and why there is a discontinuity initially wn the pads are placed i mean once we load design i/o pads and core area wil get placed right ? So in io assignment file itself they can place filler cells right ? why we will add at the later stages.........

Hi friends, this was the question from "vlsitechnology". and I would like to answer it through the board itself..

Added after 12 minutes:

If u can check the lef library, u can find that the library contains several filler cells named FILL<n>, where <n> in the cell name denotes the width of the cell in tracks.
During place and route, the FILL cells are used to connect power and ground rails across an area containing no cells. The FILL cells are also used to ensure gaps do not occur between well or implant layers which could cause design rule violations. Using wider cells where appropriate reduces the size of the layout database.
In addition, pl find in the library that the filler cells for the IO region will be different to the filler cells for the core region. U cannot place fillers for IO in core or vice versa.
Adding fillers can be done after CTS. Whenever a optimization is to be done, the fillers have to removed. why because, during optimization, the std cells can be removed or moved. this will become difficult or not possible with the fillers present in the design. So, if fillers are added before routing, then after routing and before post-route optimization, the fillers have to be removed. Once the optimization is over, the fillers have to be added again.
During ECO, also the similar procedure specified above has to be followed.
I hope, now things are clear.