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I have need for a tactile push button that I am using to cause an interrupt on a microcontroller.

I have found my desired switch (linked above) but I am having trouble deciding the best way to design the component on Eagle. I have come up with two / three methods but none of them really seem correct IMO.

Here is my first attempt:
enter image description here

This is somewhat how the datasheet depicts the symbol for the component as pins 1 and 2 are connected and the same for pins 3 and 4. However, this leads to the possibility of someone connecting something to pin one and then something different to pin two, which would be pointless. One good thing is though, that the PCB editor will allow me to leave two of the pins unconnected which is kind of desirable.

My second version of it is:
enter image description here

Here I have simply 'appended' the package pads so that they know that pins 1 and 2 are together and 3 and 4 are likewise. This makes a nice little schematic symbol as well as stopping someone connecting two different signals to effectively the same pin. However, on the PCB board it wants me to connect the two respective pins to each other as it thinks it is paramount that they are connected, however as it is mechanically connected inside the switch I don't see a point in doing this, and it makes the board more messy and a little harder to do.

Is there a standard way of making these components on Eagle or any other schematic / PCB editor? Or will one of these methods be suitable?

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  • \$\begingroup\$ In my software I would draw option two at the symbol level, and at the footprint level link pins 1 and 2, and 3 and 4. Does Eagle have a pin linking ability on footprints? \$\endgroup\$ – Matt Young Apr 17 '15 at 13:05
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    \$\begingroup\$ I think you mean "tactile"; a tactical push button would be something you'd use in battle. \$\endgroup\$ – Nick Johnson Apr 17 '15 at 13:08
  • \$\begingroup\$ @MattYoung Yes, append lets it know that they are connected together but it wants me to actually connect them with a wire / track as well \$\endgroup\$ – MrPhooky Apr 17 '15 at 13:09
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    \$\begingroup\$ @NickJohnson Hmm, yes I do... but tactical does sound more fun \$\endgroup\$ – MrPhooky Apr 17 '15 at 13:10
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When using Eagle's device editor, you can use 'append' to connect multiple pins to one signal. By default eagle expects all pins to be connected together, but by clicking the little icon to the left of the set of pins, you can toggle between 'all pins' and 'any pin' required for the connection.

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  • \$\begingroup\$ Check this works for you first - it's been a while since I used Eagle! \$\endgroup\$ – Nick Johnson Apr 17 '15 at 13:18
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If the device has four pins, show this in the schematic symbol by putting four pins on the device. This is a good habit to get into. If you give the symbol and the part different numbers of pins, some software will get very confused.

So will some people who are trying to debug or read your design :-)

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