Re: gEDA: Component Packages and PCB Land Pattern - naming Conventions

[Steve Meier <smeier@alchemyresearch.com>]

However,

The IPC-7351 naming convention doesn't seem to adress the issue of 
changing the pattern name for the soldering process.

Steve Meier



Steve Meier wrote:

> Here is an argument to move the Land Pattern naming convention from 
> IPC-SM-782A "Surface Mount Design and Land Pattern Standard" (first 
> published August 1993 last updated in April 1999) to IPC-7351 "Generic 
> Requirements for Surface Mount Design and Land Pattern Standard" 
> (Proposed Standard for Ballot October 2004)
>
> JEDEC has a package they refer to as MO-153  this is sometimes refered 
> to as TSSOP. There exist devices which use this package,
>
> Basically it is a package with gull wing leads on two sides with a 
> pitch between leads of 0.65mm
>
> For the package MO-153AB wich is a 14 pin version of this package 
> there is no defined landpattern in the IPC-SM-782A and thus no 
> Regestered Land Pattern Number. The regestered land pattern number 
> being the prefered way to name the land pattern for this type of package.
>
> The new standard doesn't require package registrataion instead it has 
> a naming convention that allows new packages to be introduced and to 
> have meaningfull names created for the packages land pattern.
>
>
> For example:
>
>
> JEDEC JEP95  package type:  MO-118AA
> Package Description: Shrink Small Outline Package (SSOP) 48 Pins
> IPC-782A  Regestered Land Pattern Number:  330A
>
> I think the IPC-7351 name is as follows.
>
> IPC-7351 Name: SSOP63P10-48
>
> IPC-7351 name disected
>
> SSOP
> 63            0.635mm pitch
> 10            10.35mm Lead Span  (distance from tip of one lead to the 
> tip of the lead on the oposet side of the device)
> -                seperator before the pin count
> 48             for the 48 pins
>
>
> Steve Meier