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I have a hierachical multichannel design and I´m having problems to set properly the project properties so that the following issue is removed. child sheet with power port connected to port

As you can see one of the ports of the child sheet is connected to the Vm_GND power port net. Once recompiled the schematics I have found that when alt+click over this net, the other Vm_GND port of other schematic sheets in the design do not highlight.

When importing this design to PCB the I_SNS- net is not connected to Vm_GND in the PCB of so this is a major issue because as you can see it should be.

These are my project options:

enter image description here

What am I doing wrong?

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  • \$\begingroup\$ I_SNS- is shown as an "output" port. Where is the matching "input" port to connect the other channels? I don't recommend using the "output" I/O Type for this, I suggest using "unspecified". I don't think multiple output ports will connect to one another without a matching "input" port, but this may not be the case with "unspecified". \$\endgroup\$ – DerStrom8 Dec 14 '17 at 14:45
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    \$\begingroup\$ Also, if power ports are global, why bother with the I_SNS- sheet port at all? \$\endgroup\$ – DerStrom8 Dec 14 '17 at 14:46
  • \$\begingroup\$ I_SNS- is an output port and it will be connected to an input port in another child sheet. \$\endgroup\$ – user6127833 Dec 14 '17 at 14:50
  • \$\begingroup\$ On the other hand, I think that the problem comes when connecting a port to a power port this way. Altium compiler has to decide wether to use the global power port or the output port (I_SNS- in this case). If Altium assigns ISNS- net then it cannot be connected to the global power port. But I thought that using "Power port names take priority" would solve this type of problems. Maybe a Net Tie should be used in this case... \$\endgroup\$ – user6127833 Dec 14 '17 at 14:53
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    \$\begingroup\$ A global net either is, or it isn't. By connecting a global power symbol to a port, you're reducing its scope to a local net. Either get rid of the port, and keep Vm_GND global, or get rid of the Vm_GND symbol, and use local nets via ports. Or add a level of complexity, and un-manageability, by using net ties. \$\endgroup\$ – Chris Knudsen Dec 14 '17 at 15:04
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It looks like you're trying to use Kelvin connections so that your sense traces don't carry any current. To do this best in Altium, use a "net tie" component. It allows you to connect two nets together at a specific point on the PCB. Google "Net tie" and Altium and you should be able to find what you need.

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  • \$\begingroup\$ Yes, thanks for the tip. I indeed need this type of connection so, as I thought, net tie is to be used. Nonetheless I particularly hate net ties so that's the reason why I connected this circuit this way. \$\endgroup\$ – user6127833 Dec 14 '17 at 19:17

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