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special net not being routed when sroute ran

diablo

 Hi all,

I am trying to route special net "bdpd_5v" using sroute. However, sroute is not routing the net.

This bdpd_5v signal connects output pin in one of the IO cell  to input pin 'BDPD_5V' of rest of the IO cell. This signal detecs the presence of power in IO cell and prevent backdrive leakage on absence of power.

I have set this signal  as special net

 "setnet -net bdpd_5v     -type special -setTermSpecial"

Then used 'sroute' with following options 

sroute -connect { blockPin padPin padRing corePin floatingStripe }
-layerChangeRange { 1 6 } -blockPinTarget { nearestRingStripe
nearestTarget } -padPinPortConnect { allPort oneGeom }
-checkAlignedSecondaryPin 1 -blockPin all -allowJogging 1
-crossoverViaBottomLayer 1 -allowLayerChange 1 -targetViaTopLayer 6
-crossoverViaTopLayer 6 -targetViaBottomLayer 1 

The net was not routed by sroute. I had also connected the net to the global net using

"globalNetConnect bdpd_5v    -type net -net bdpd_5v -all -verbose" 

and ran 'sroute' with the same option as above. This net is still not routed.

Any suggestions?

The reason I wanted to use sroute for this net is while routing this net through nanoroute, it is buffering this net inside core using standard cells which is at 1.8V and this net is at 5V. 

Thanks a lot for your time. 

 

Parents
  • diablo

     Thanks Kari. My intent is just to avoid buffering the nets because when those analog nets, which are at 5v domain, get buffered it is incorrectly connected to 1.8V standard cells. I just want to prevent this from happening. I know i could use CPF and define different power domain area but currently we dont have license to use CPF and level shifter insertion, so i am figuring out different flow to avoid the 5V net  to be routed through 1.8V standard cells. I think 'set_dont_touch' on all the analog nets will work for me. 

     

     

Reply
  • diablo

     Thanks Kari. My intent is just to avoid buffering the nets because when those analog nets, which are at 5v domain, get buffered it is incorrectly connected to 1.8V standard cells. I just want to prevent this from happening. I know i could use CPF and define different power domain area but currently we dont have license to use CPF and level shifter insertion, so i am figuring out different flow to avoid the 5V net  to be routed through 1.8V standard cells. I think 'set_dont_touch' on all the analog nets will work for me. 

     

     

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