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Help me with off grid and no grid errors

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+routing +off grid +pins

Hi,
After DRC,I found a lot of off grid and no grid quesiton,and a few short
and min space error,the report as followed:

NOGRID: IOPin of Net clk ( M2 )
Bounds : ( 394.115, 889.660 ) ( 394.315, 889.860 )

NOGRID: Pin of Cell mc_top/U108 ( M1 )
Bounds : ( 370.705, 535.330 ) ( 371.460, 535.590 )

NOGRID: Special Via of Net VDD ( M4 )
Bounds : ( 567.000, 561.145 ) ( 573.000, 561.435 )

OFFGRID: Regular Via of Net wb_data_pad_i[26] ( M5 )
Bounds : ( 454.050, 373.115 ) ( 454.510, 373.495 )

OFFGRID: Regular Via of Net mc_top/rf_dout[11] ( M5 )
Bounds : ( 331.050, 494.885 ) ( 331.510, 495.265 )

and power antenna:

ANTENNA: Special Wire of Net VDD ( M1 )
Bounds : ( 297.250, 486.670 ) ( 297.250, 486.670 )

BEST REGARDS
 

Re: off grid question

Hi,

The problem is coming because you standard cells pins are not falling on the grid for the router to access.You can solve the problem by specifying the correct offset.
 

Re: off grid question

Hi,
Thanks a lot!
Maybe should I modify the lef file?I used artisan smic13 lib as followed:

LAYER METAL1
TYPE ROUTING ;
WIDTH 0.160 ;
SPACING 0.180 ;
SPACING 0.18 LENGTHTHRESHOLD 1.0 ;
SPACING 0.20 RANGE 0.4 10.0 USELENGTHTHRESHOLD ;
SPACING 0.60 RANGE 10.05 100000.0 ;
PITCH 0.410 ;
OFFSET 0.205 ;
........
END METAL1
shoud I modify the offset,how to do it,need I communicate with artisan?
 

Re: off grid question

First if you are importing the design in a DEF format make sure the UNITS of LEF and

DEF or correct(they should be same). Next you can turn the routing grid on in the

layout(each layer will be having one) and see wether the standard cell pins are falling

on the grid. I am not sure which tool u use but the above procedure applies to all.

Best of Luck
 

Re: off grid question

Hi,
If I found the pin is not in the track as mentioned above.need I modify it,
because it is in the library.
 

Re: off grid question

Which tool are you using?.Caliculate an offset which will make sure all the pins are on

the grid. There will be a internal paramers in some tools to specify the offest or else

you need to specify in the LEF(But this is not recommended).Better ask your tool

support enginner on how you specify the offset with the internal parameter.If still the problem doest solve email me

All the best
 

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