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Connecting mechanical pins to a ground plane

ddchar

My board design contains a couple of instances of an SMA connector.  The Capture part defines only the center signal pin.  The footprint has this pin and four mechanical pins.  The mechanical pins also provide the signal return connection and should be connected to the ground plane.  What is the best way to make these connections?  Do I need to edit the Capture part and add the ground pins or is there a way to associate these with the ground plane in Presto?  Thanks.

Parents
  • Ulf K
    0

    "Been there".

    Advice: A l w a y s create connectors and other mechanical parts using "connectable"/passeive pins. Sometimes, connecting metal also acts as improving ESD protection. In regard to connectors, using "connectable pins" the layout designer then have a choise: Either connect them or, if it is desirable not to, simply add a "dangle" (x) = not connected. That will prevent a DRC error.

    IMHO, the only time a mechanical (ie: solderless pad (hole)) should be added is when creating a part that has guide holes without copper. And that is done in the layout editor. Just make sure that a suitable copper keep-out area around these holes are added.

    Crating schematic symbols with multiple pins of same net such as a thru-hole or end launcher SMA connector with 4 ground pins can be accomplished so that only one ground pin is visible is using the "pack short" property, but sometimes this rises quesrtion during auditing. I usually takes the easy way out and simply adds the four gnd pins apart from the center (RF) pin.

Reply
  • Ulf K
    0

    "Been there".

    Advice: A l w a y s create connectors and other mechanical parts using "connectable"/passeive pins. Sometimes, connecting metal also acts as improving ESD protection. In regard to connectors, using "connectable pins" the layout designer then have a choise: Either connect them or, if it is desirable not to, simply add a "dangle" (x) = not connected. That will prevent a DRC error.

    IMHO, the only time a mechanical (ie: solderless pad (hole)) should be added is when creating a part that has guide holes without copper. And that is done in the layout editor. Just make sure that a suitable copper keep-out area around these holes are added.

    Crating schematic symbols with multiple pins of same net such as a thru-hole or end launcher SMA connector with 4 ground pins can be accomplished so that only one ground pin is visible is using the "pack short" property, but sometimes this rises quesrtion during auditing. I usually takes the easy way out and simply adds the four gnd pins apart from the center (RF) pin.

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  • ddchar
    0 in reply to Ulf K

    Thanks for the tips.  I was able to make the connections by adding a net name of Shield to each of the (formerly) mechanical pins and then adding a Shield net alias to the GND net on the schematic.  It seems odd that the PCB footprint had no provision for connecting the body/shield/return to a net.  All of the MCX connectors I looked at had a similar setup.

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