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LVS does not accept proper termOrder

Kabal

This problem differentiates from another post, but it is more relevant to termOrder case, thats why I created separate this thread.

The problem is that during LVS I get a lot of pin mismatches, however; according to the CDL netlist for LVS all the schematic-to-pin connection in the top cell are correct.

Again, I have one cell with layout view generated before, and with a auCdl view as a symbol. So it has just two views, layout and auCdl. The name of that cell with two views is refleks_switcher. I instantiate the auCdl view of refleks_switcher cell in another top level cell called refleks_switcher_wrapper. 

After that, I export the CDL netlist for LVS. Then I go ahead and create another layout, that layout is basically a wrapper layout, I just instantiate refleks_switcher layout view and then add ports with "_top<N>" suffix in them, where N is just number of each individual port. 

Then I perform the LVS of the top layout view, and get a lot of pin mismatch errors. For example something like this:

Pin           SchNet                      : LayNet
---             ------                           : ------
rst            pwm_ctrl_top              : rst_top
pwm_ctrl   pwm_out_top<0>        : pwm_ctrl_top

This does not make any sense! If you look at the attached CDL netlist file, you will see that the cell refleks_switcher or XI19 is connected properly pin-by-pin according to SUBCKT and PININFO statements! and same goes for layout! I have no idea why this tools acting crazy!

 


I am attaching 5 files in this and next posts:

cdf_properties.png - snapshot of refleks_switcher CDF properties, where you can clearly see my termOrder defined.
schematic_top.png - snapshot of schematic in top cell called refleks_switcher_wrapper with the auCdl view of refleks_switcher cell
refleks_switcher_wrapper.netlist.lvs - a CDL file produced from top schematic for LVS.
cdf_dump.txt - CDF dump of refleks_switcher cell
lvs_output.txt - an LVS output which shows pin errors.

 

 

Parents

  • Which IC615 subversion are you using? Don't think you'd ever want to use cellIgnore for this, because that just removes the block - it won't short them. The cds_thru has got lxRemoveDevice on it (which caused the CDL netlister to attempt to short the nodes in earlier IC615 versions, and if that failed, it would netlist as a small resistor); in later IC615 subversions it should netlist it as a *.CONNECT statement, and so the shorting is done in the LVS tool. With the small resistor, a low enough *.RESI is needed to short inside the LVS tool.

    I'm not really sure precisely what the problem is that you have with [ and <> - I'd need to see the data. Maybe you can report this to customer support so we can take a full look at your  data.

    Regards,

    Andrew.

Reply

  • Which IC615 subversion are you using? Don't think you'd ever want to use cellIgnore for this, because that just removes the block - it won't short them. The cds_thru has got lxRemoveDevice on it (which caused the CDL netlister to attempt to short the nodes in earlier IC615 versions, and if that failed, it would netlist as a small resistor); in later IC615 subversions it should netlist it as a *.CONNECT statement, and so the shorting is done in the LVS tool. With the small resistor, a low enough *.RESI is needed to short inside the LVS tool.

    I'm not really sure precisely what the problem is that you have with [ and <> - I'd need to see the data. Maybe you can report this to customer support so we can take a full look at your  data.

    Regards,

    Andrew.

Children
No Data

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