In Eagle, I would like to include SN74HC595 shift registers in my project. I found a library online a few months ago (can't find source anymore) that has this part.

The symbol looks like this:

enter image description here

However, I noticed the symbol does not have power and ground pins, which is contrary to all of the other devices I've seen and created before. I had no idea how I would actually connect it to the same power supply I'm using for all other components in my schematic.

So I opened up the device in the library, and it looks like this:

enter image description here

It seems there's a second symbol (on the left) that goes only to VCC and GND, and those are assigned to the relevant power and GND pads on the package.

My issue is that my power rails on my schematic are labeled '5V' and 'GND'. I've read that I can 'simply' rename the 'VCC' pin to '5V' and that it will automatically connect to any '5V' net in whatever schematic I put it in. This, however, didn't work.

I've also consulted Eagle's awful product support pages to no avail.

How do I hook this component up to my '5V' line?

[ note: GND hooks up automatically to the 'GND' net in my schematic ]

  • 4
    \$\begingroup\$ You shouldn't be using net-named automatic connections anyways. Place a power port on the pins! \$\endgroup\$ Jun 26, 2013 at 22:57
  • \$\begingroup\$ Funny this came up today. I was just trying to split the four gates of a 100-pin IC into two different pages in my schematic, and the only way to do this is to run invoke from the command line! \$\endgroup\$ Jun 26, 2013 at 23:26
  • \$\begingroup\$ Connor, I agree. Much better to have all that information present on the schematic than hidden in the device file, even if it does save space. \$\endgroup\$
    – ryantuck
    Jun 29, 2013 at 17:15

4 Answers 4


"Invoke" command resolves this.

enter image description here

I've got only Eagle 5.11.0 in front of me at the moment. But, this haven't changed in 6.3.0

@ScottSeidman had beat me to the answer, while I was annotating the screenshot.

  • \$\begingroup\$ +1 I'd say details (and images) outweigh speed to answer. \$\endgroup\$
    – JYelton
    Jun 26, 2013 at 22:04
  • \$\begingroup\$ I upvoted, as your answer is much more complete! \$\endgroup\$ Jun 26, 2013 at 23:20
  • \$\begingroup\$ For reference, in EAGLE 7.6.0 the "Invoke" button now looks like a black gate and gray gate next to one another (see i.imgur.com/Mq1HiaE.png) \$\endgroup\$
    – Doktor J
    Aug 31, 2016 at 2:35

You use the INVOKE button. enter image description here It looks like four AND gates with an arrow on the lower left one. It will let you hook up pins that are attached to default nets.


If it were OrCAD you'd just use multiple names on nets or attach a Vcc bar to the 5V rail. This effectively means that any symbols with Vcc for pin 14 (or 16 or whatever) get attached to 5V because there is a netname of Vcc attached to 5V in the schematic.

I don't know if this will work in EAGLE but it may trigger some thought.

  • \$\begingroup\$ OrCAD triggers nasty thoughts! The word reminds me of orchiectomy for some reason \$\endgroup\$ May 16, 2014 at 15:00

If all of your circuit uses logic devices with the same supply voltage, name the supply VCC instead of 5V for example
Also I use power planes on my boards, I create a polygon on top and bottom layers, naming them GND and VCC respectively
When I invoke Ratsnest function, it draws the copper layer, this also connects to the relevant terminals on IC's and connectors
With SMD you must of course create via to connect to the plane on the opposite of the pcb
Power planes of this nature give better supply characteristics and due to the capacitance effect between the planes, it also reduces high frequency noise


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