Author Topic: Recommended DIP footprint  (Read 1358 times)

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Offline Sparky49Topic starter

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Recommended DIP footprint
« on: December 03, 2021, 07:50:43 pm »
Hi I would like to make a footprint for a DIP20 package, but I cannot find any information regarding the recommended distances between pads. I know the dimensions of the part (standard PDIP20), but I can't find a single source outlining suggested distances between the holes/pads on the PCB, hole size, pad size, etc. Does anyone have this info? Thanks in advance.
 

Offline james_s

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Re: Recommended DIP footprint
« Reply #1 on: December 03, 2021, 08:18:49 pm »
Surely whatever EDA you're using already has a DIP-20 package? Otherwise look at some of the other DIP packages for ideas. It really isn't critical, generally you want the pads as large as practical, leaving enough space to run a trace between two adjacent pads. Many times elliptical pads are used to increase the spacing between them.
 

Offline Sparky49Topic starter

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Re: Recommended DIP footprint
« Reply #2 on: December 03, 2021, 08:48:16 pm »
Thanks, I use Altium and it doesn't have any prebuilt packages (unless I've missed something obvious after all these years lol). If I could find guidance on a smaller or larger device I would just extrapolate the pad spacing, but I can't find that primary information.
 

Online jpanhalt

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Offline Sparky49Topic starter

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Re: Recommended DIP footprint
« Reply #4 on: December 03, 2021, 09:02:28 pm »
Thanks, I appreciate the links to existing models/footprints, but I would like to know the recommended dimensions/procedures etc so I can make my own. What references did the people who made those footprint files use?
 

Offline james_s

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Re: Recommended DIP footprint
« Reply #5 on: December 03, 2021, 09:03:57 pm »
The datasheet probably, and a mix of experience and common sense. Making a DIP package is not unlike making any other package, it's not rocket science.
 

Offline floobydust

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Re: Recommended DIP footprint
« Reply #6 on: December 03, 2021, 09:12:00 pm »
Narrow (shrink) DIP-20 no different than more popular shrink DIP-28. There's wide variations in footprints for through-hole parts.
Some designers go with small pads so they can run one or two :o  traces between pins. Easier if pad shape is rectangular. Hole size is to accommodate any socket, machined pin sockets have bigger pins.
 

Offline Doctorandus_P

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Re: Recommended DIP footprint
« Reply #7 on: December 04, 2021, 01:13:09 pm »
Any datasheet of an IC should have the dimensions of the package.
Usually it is one of the last pages of the datasheet.
 

Offline westfw

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Re: Recommended DIP footprint
« Reply #8 on: December 07, 2021, 07:53:56 am »
Quote
I would like to know the recommended dimensions/procedures etc so I can make my own.
I'd normally start with the required hole size (usually 0.7 to 0.8mm.  May depend on whether you plan to use a socket.)  For some CAD packages, this will imply a pad size, but I'd normally let that expand a bit for easy hand-solderability and robustness.  Or shrink it to the minimum supported by my PCB manufacturer if I want to run a trace or two between pads.
I believe you are more likely to be limited by your manufacturing process than by IC specifications.  (Though occasionally there might be special considerations - extra thick leads for heat dissipation or something.  In those cases, I'd expect advice in the datasheet.)
 


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