how to implement sp1t,sp2t,sp3t switch

There seems to be some misunderstanding here. The sp*tswitch components from analogLib are the "switch" component in spectre, as Shawn pointed out. The are not controlled by voltages (so the sp3tswitch doesn't have 1V, 2V, 3V inputs). What the switch component does is allow you to set the switch in different positions for different analyses. The primary idea behind this is to allow you to (say) have the switch in one position for DC, but different for AC. This was a traditional approach used for measuring open loop gain (close the loop for DC, open for AC), but a better approach for that problem is to use the stb (stability) analysis in spectre instead, as this keeps the loop closed all the time and so models the loading effects properly.

There may be other useful applications for this switch, but they are relatively rare. The different variants in analogLib just have different numbers of throws - the sp3tswitch is a single pole three throw switch, so each switch has four positions - open, or the three different closed positions - hence the 0,1,2,3 values for each analysis.

If you want a voltage controlled switch, the analogLib component is called switch (rather confusingly) which corresponds to spectre's "relay" component.

Documentation on analogLib components can be found by using the Help from within Virtuoso, or running `cds_root virtuoso`/tools/bin/cdnshelp and then navigating to find "Analog Library Reference" (you could probably use various searches to find that manual). 

Also, you should (as Shawn suggested) be able to run "spectre -h XXX" where XXX is the component name (e.g. switch, relay) in a UNIX terminal. If that doesn't work, look carefully at your setup. The same information is in the spectre documentation, but if spectre can't be found from the command line, then I suspect you wouldn't be able to find cdnshelp from the command line either. You may be doomed.

Regards,

Andrew.

There seems to be some misunderstanding here. The sp*tswitch components from analogLib are the "switch" component in spectre, as Shawn pointed out. The are not controlled by voltages (so the sp3tswitch doesn't have 1V, 2V, 3V inputs). What the switch component does is allow you to set the switch in different positions for different analyses. The primary idea behind this is to allow you to (say) have the switch in one position for DC, but different for AC. This was a traditional approach used for measuring open loop gain (close the loop for DC, open for AC), but a better approach for that problem is to use the stb (stability) analysis in spectre instead, as this keeps the loop closed all the time and so models the loading effects properly.

There may be other useful applications for this switch, but they are relatively rare. The different variants in analogLib just have different numbers of throws - the sp3tswitch is a single pole three throw switch, so each switch has four positions - open, or the three different closed positions - hence the 0,1,2,3 values for each analysis.

If you want a voltage controlled switch, the analogLib component is called switch (rather confusingly) which corresponds to spectre's "relay" component.

Documentation on analogLib components can be found by using the Help from within Virtuoso, or running `cds_root virtuoso`/tools/bin/cdnshelp and then navigating to find "Analog Library Reference" (you could probably use various searches to find that manual). 

Also, you should (as Shawn suggested) be able to run "spectre -h XXX" where XXX is the component name (e.g. switch, relay) in a UNIX terminal. If that doesn't work, look carefully at your setup. The same information is in the spectre documentation, but if spectre can't be found from the command line, then I suspect you wouldn't be able to find cdnshelp from the command line either. You may be doomed.

Regards,

Andrew.