ICC的LVS出现了VSS的open，所有出现先VSS的地方全部出错了【已解决】

白兰地

在verify_lvs的时候出现了float和一个vss  open，open整个白茫茫的一片，出现VSS的地方都出现了错误，没法具体定位，是哪里设置不合理了吗？ERROR : OUTPUT PortInst fzu8051_top_inst/MCU8051/i_cpu/cyc1/U9 Y doesn't connect to any net.
ERROR : INPUT PortInst fzu8051_top_inst/MCU8051/i_cpu/cyc1/U9 A(429955) in net VSS(462112) is floating.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/xunhuan1/sval_reg[11] Q doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/xunhuan1/sval_reg[9] Q doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/xunhuan1/sval_reg[17] Q doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/round16_end_dout1/dout_in_reg[20] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/round16_end_dout1/dout_in_reg[12] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/round16_end_dout1/dout_in_reg[19] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/shuchuchuli1/dout1_reg[44] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/shuchuchuli1/dout1_reg[43] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/round16_end_dout1/dout_in_reg[8] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/round16_end_dout1/dout_in_reg[9] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/shuchuchuli1/dout1_reg[53] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/round16_end_dout1/dout_in_reg[26] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/round16_end_dout1/dout_in_reg[25] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/shuchuchuli1/dout_final_reg[34] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/shuchuchuli1/dout1_reg[40] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/shuchuchuli1/dout1_reg[41] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/round16_end_dout1/dout_in_reg[14] QN doesn't connect to any net.
ERROR : OUTPUT PortInst fzu8051_top_inst/DES/shuchuchuli1/dout1_reg[50] QN doesn't connect to any net.



整个图中出现VSS的地方，几乎都出错了！

小干爹z2z

期待大神回复。是否是因为没有via什么的？
有没有tie 和 drive_pg_connection.

damonzhao

drive_pg_connection
output open没关系

overdriver

先verify_pg_nets 确认PG有没有问题，check_mv_design 去看power 连接，都没问题了再搞PV

白兰地

回复 2# 小干爹z2z

有连接，我又特意去连了一下。 怎看看是不是via的问题呢，其他地方via都可以自动用上的说

白兰地

回复 3# damonzhao


    所有output的float都没事吗？
    电源地有链接的，不知道是不是因为之前修DRC的时候，修改了下网表，但是没改VSS的说。

    http://bbs.eetop.cn/thread-441780-1-1.html

白兰地

回复 4# overdriver

恩恩verify_pg_nets 的rail都给修了，我再去试试

白兰地

回复 4# overdriver

看来下感觉都没什么问题的说，警告之前也出现过，做PV是什么意思呢？
   icc_shell> check_mv_design  -power_nets--------------------------------------------------------------------------------
       Power/Ground Pin Connection Checks
--------------------------------------------------------------------------------


Power/Ground Connection Summary:


P/G net name                P/G pin count
--------------------------------------------------------------------
Other power nets:                 12404
Unconnected power pins:           0


Other ground nets:                12404
Unconnected ground pins:          0
--------------------------------------------------------------------
Warning: Power connection/checking is skipped for 24800 power pins because the required power pin information cannot be found in logical libraries. (MV-510)


--------------------------------------------------------------------------------
       Supply Operating Voltage Checks
--------------------------------------------------------------------------------
No Errors/Warnings Found.


Please review report above for warnings and errors.
1
icc_shell> verify_pg_nets
Cell design_top.err existed already. Delete it ...
Checking [VDD]:
        There are no floating shapes
        All the pins are connected.
        No errors are found.
Checking [VSS]:
        There are no floating shapes
        All the pins are connected.
        No errors are found.
Checked 2 nets, 0 have Errors

damonzhao

回复 6# 白兰地

input不能floating但是output是可以的，只要确实是floating的，那就没问题

和另个帖子的问题应该没关系。如果不放心，可以从头来一遍试试

白兰地

回复 9# damonzhao


   恩恩，感觉那边也没改到VSS，不过之前一次没出现open，我再去试一下看看
   看来下IO的文档里面写着要加隔离PBREAK，里面推荐的pad的摆放方式像下图那样，是不是所有的电源pad最好这样摆放呢，因为感觉电源pad一般会放到四周去。PVDD是1.8V  PDVDD是3.3V
PBREAK is used to break power and ground rings and to isolate substrate. They have back-to-back diodes between different ground signals