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post-simulation question about dummy cells

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ilter

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no dc path to ground from node

Dear all,
I use calibre -pex. My circuit has some dummy cells and my layout also has these. I run drc and lvs and they are ok. So I run pex. Then I simulate my post-simulation by hspice. But there are some errrors like below. How do I do ?
If I don't kill my dummy cell, how do I do? If you know, please tell me . Thanks.

**error** no dc path to ground from node 0:n_xi0/net05249_xi0/xi2123/mm45_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net05249_xi0/xi2123/mm42_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net05250_xi0/xi2123/mm39_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net05250_xi0/xi2123/mm52_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net05254_xi0/xi2122/mm45_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net05254_xi0/xi2122/mm42_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net05255_xi0/xi2122/mm39_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net05255_xi0/xi2122/mm52_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net04906_xi0/xi2057/xi0/mm0_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net04905_xi0/xi2057/xi0/mm1_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net04904_xi0/xi2057/xi0/mm2_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net04905_xi0/xi2057/xi0/mm3_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net04906_xi0/xi2057/xi0/mm4_g defined in subckt 0





**error** no dc path to ground from node 0:n_xi0/net04904_xi0/xi2057/xi0/mm5_g defined in subckt 0
 

number of nodes with no dc path to ground

hi ilter,
I don't think dummy component should be floating. so what about connect your floating node to some fixed
potential. especially active component such as mos bipolar.
regards
 

floating dangling node circuit

(1) try use .option dcstep=1 in hspice, which will convert cap to res in dc analysis.
(2) try remove dangling/floating nodes in extraction tools when extraction.

if (1) (2) fails, you need to connect your floating nodes to gnd with a large resistor.
 

**error** no dc path to ground from node

Check your Hspice version.

In version98, both floating gate&drain are forbidden;
In Version2000 or later, only floating gate are forbidden.
 

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