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Electronics => Projects, Designs, and Technical Stuff => Topic started by: electosleepy on August 16, 2016, 02:21:41 am

Title: IPC Courtyard Standards for Odd Components (Connectors)
Post by: electosleepy on August 16, 2016, 02:21:41 am

Hi,

How do I determine what would be the nominal courtyard dimensions for a connector? Is there a rule of thumb ie, 1mm excess around the component?

Title: Re: IPC Courtyard Standards for Odd Components (Connectors)
Post by: D3f1ant on August 16, 2016, 11:25:00 pm

Depends on the connector and dimension tolerances shown on its datasheet. Generally make courtyard slightly larger than the worse case dimensions.

Title: Re: IPC Courtyard Standards for Odd Components (Connectors)
Post by: Christe4nM on August 17, 2016, 11:17:03 am

IIRC there is indeed such a standard like x mm excess from the component in IPC 7351 (latest is the 7351C released early 2016)

The actual 'x' depends on whether you need L(east) N(onminal) or M(ost) sized footprints.

IIRC you might also choose whether you only want to put the component's physical size and copper pads inside the courtyard, or the silkscreen too.

I do the latter, with 0.25 mm excess.

Courtyard doesn't need to be a box, it can follow the contours of a non box shaped footprint.

Title: Re: IPC Courtyard Standards for Odd Components (Connectors)
Post by: electosleepy on August 18, 2016, 02:52:29 am

Thanks for the advice, I would like to know where should I mark the origin of a connector such as a PMOD[1]? Should it be in the center of the mechanical body or should it be in the center of the courtyard or should it be in the center of the pins as shown in the attached picture? What is the best practice for the assembler?

http://sullinscorp.com/drawings/101_P(N)PxCxx2LJBN-RC,_10494-H.pdf (http://sullinscorp.com/drawings/101_P(N)PxCxx2LJBN-RC,_10494-H.pdf)

Title: Re: IPC Courtyard Standards for Odd Components (Connectors)
Post by: Christe4nM on August 18, 2016, 09:08:57 am

Quote from: electosleepy on August 18, 2016, 02:52:29 am

Thanks for the advice, I would like to know where should I mark the origin of a connector such as a PMOD[1]? Should it be in the center of the mechanical body or should it be in the center of the courtyard or should it be in the center of the pins as shown in the attached picture? What is the best practice for the assembler?

http://sullinscorp.com/drawings/101_P(N)PxCxx2LJBN-RC,_10494-H.pdf (http://sullinscorp.com/drawings/101_P(N)PxCxx2LJBN-RC,_10494-H.pdf)

"The land pattern origin is typically located at the center of gravity of the
component, but sometimes this is difficult to calculate with irregular
shaped components, so Pin 1 is used in these cases. Also Pin 1 in most
through-hole connectors."

From "what's new in IPC 7351C" by Tom Hausherr. http://cskl.de/fileadmin/downloads/PCBLIBRARIES/Documentation/What-is-New-in-IPC-7351C_.pdf