Footprint for an Ethernet connector

[RChadwick7]

I was hoping someone would know which footprint I should use for this connector:
https://www.aliexpress.us/item/3256805919581391.html
It also looks the same as this:
https://www.amazon.com/FMHXG-Shielded-Network-Connector-Computer/dp/B0BRQ2R8HW

My guess is that it’s “Connector_RJ:RJ45_Ninigi_GE” but hoping someone has confirmation.
Thanks!

[hermit]

If you are buying a component without a data sheet available you’re going to have first buy the component and check its’ dimensions.

[teletypeguy]

Looks similar to this 8p8c from amp (pins are on a 50-mil grid). Maybe you can tweak as needed and add the shield can plated holes.

J_modular_8P8C_low_profile_amp_5555164-1.kicad_mod (5.6 KB)

[paulvdh]

@RChadwick7

It also looks the same as this:

Looks can be deceiving, and there are probably hundreds of variants for footprints of RJ45 connectors.

[tutorial] Test fitting Footprints

A small demo to show how I test fit footprints. It’s a combination of a few things to make it work perfectly. The first step is to print a PCB mirrored on a piece of Paper: PcbNew → File → Print → Options Mirror → Print. 2nd step: Take a needle and pre-punch all the mounting holes into the paper. (For the large holes I used a hole punch). 3rd step: Carefully put the connector into the sheet of paper. 4th step: Take a picture or scan the whole contraption with a flatbed scanner. This make…

[RChadwick7]

Thanks for the responses! I found another seller who had a CAD drawing: https://www.aliexpress.us/item/3256803534185015.html
Is there a way to import or overlay a JPG over the footprint to compare?

[paulvdh]

PCB Editor / Place / Add Image …

It can be of some help, but don’t rely on it. There is no guarantee that a picture from another (or even the same) seller is compatible with your footprint, or that the picture itself is actually accurate.

[teletypeguy]

Well, the drawing gives you dimensions and hole sizes, so why would you waste time farting around scaling and importing a crappy drawing to overlay when you have the exact numbers to build a footprint the proper way? Which would take less than five minutes, btw.

[hermit]

If you plan on making the board, just go ahead and get your connectors, and then finalize the board. If you simply MUST know then go to someplace like Digikey. They might be a tad more expensive but you have over 16K to choose from and each has a proper datasheet.

[paulvdh]

The first time I used a RJ45 connector, in a self designed PCB, I was inexperienced, did not have a datasheet present and only did a cursory check. The holes were off by up to 1.5mm and I did not spot that. By carefully bending the pins of the connector, and fiddling with tweezers during insertion I managed to put a connector on a PCB in about 4 minutes. So for that batch of 30 PCB’s with two connectors each, that took about 4 hours of assembly time. And that is what prompted me to make that test fitting tutorial I posted earlier. So consider yourself warned.

Edit: Small clarifications

[Piotr]

@paulvdh

The first time I used such connectors in a self designed PCB, the holes were off by up to 1.5mm.

I’m very surprised.
What you understand under ‘such connectors’. The Ethernet connector or Ethernet connector from aliexpress.
With holes according to datasheet I had never any problem with this connectors.
But you have to be care. For example the connector I used had all LED pads (4 holes) in one line and the other firm connector looking as direct replacement had everything the same except each LED had its pads along 45° line.