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I found NT1 in a Microchip demo board schematic (103-00419-R1.pdf) but can't figure out what it means.

There is a box with a note saying "Default connection between 1-2. User to cut the trace if 5V VDD is needed.", with NT1 as a little box with wires going to pins 1 and 2 on the header.

I can't find the refdes on Wikipedia or Google in general, so I'm out of ideas. Here's a screenshot of the part in question (on the right side):

enter image description here

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  • \$\begingroup\$ Instead of requiring people to download a zip, unpack, locate a file, open and locate the part of the file where the information is in, you could provide a screenshot of the interesting part. \$\endgroup\$ – PlasmaHH Jun 27 '17 at 14:13
  • \$\begingroup\$ @PlasmaHH Sorry, I somehow completely forgot I could do that. One second. \$\endgroup\$ – Jashaszun Jun 27 '17 at 14:14
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"Net Tie".

You will note that one one side of the net tie 'component' the net is named 3.3V, on the other VDD. PCB cad systems usually assume that all connected nets have the same name, but that components have can have more then one pin, so to allow you to connect two nets together in a defined place you create a component having two pads, no BOM entry and a footprint that connects the two pads together. Placing this component then satisfies the need for each net to have a single name while allowing the nets to be connected together at a defined point.

Altium (Which is what that was drawn in) calls these net ties hence NT.

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I've no clue what NT could stand for.

But on the bottom layer of the PCB there is a connection between the two pins of the header which is not covered by solder mask.

So I guess the NT part is just that: a wire with no solder mask to allow the user to more easily break that connection in case he wants to try something else. It probably has the dimensions to fit to a standard header just fine.

Bottom PCB layout in question

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  • \$\begingroup\$ How would one actually cut that trace? (I don't even have the board, but am just curious.) \$\endgroup\$ – Jashaszun Jun 27 '17 at 14:21
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    \$\begingroup\$ @Jashaszun I usually use a scalpel for that kind of work, or a small screwdriver works as well (carefully, otherwise you might slip and rip off some parts). \$\endgroup\$ – Arsenal Jun 27 '17 at 14:23
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    \$\begingroup\$ @Jashaszun Well you have copper, which is a rather soft metal (hardness is only a fifth of steel or something like that?), and only some µm thickness (18 µm to 70 µm usually). \$\endgroup\$ – Arsenal Jun 27 '17 at 14:29
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    \$\begingroup\$ Looking at the board, "NT" could mean "Narrow Trace" \$\endgroup\$ – Peter Bennett Jun 27 '17 at 15:02
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    \$\begingroup\$ NT = Net Tie probably \$\endgroup\$ – laptop2d Jun 27 '17 at 15:42

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