PCB Libraries Forum : Square pads standard? https://www.PCBLibraries.com/forum/ Thu, 09 Apr 2026 21:17:10 +0000 Fri, 19 May 2023 23:43:28 +0000 http://blogs.law.harvard.edu/tech/rss Web Wiz Forums 12.07 360 https://www.PCBLibraries.com/forum/RSS_post_feed.asp?TID=3155 <![CDATA[PCB Libraries Forum]]> https://www.PCBLibraries.com/forum/forum_images/PCBLForumLogo.gif https://www.PCBLibraries.com/forum/ <![CDATA[Square pads standard? : I completely agree that square...]]> https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post13042.html#13042 Author: williamswelsh75
Subject: 3155
Posted: 19 May 2023 at 11:43pm

I completely agree that square pads should be the standard.

They provide a much more comfortable and ergonomic experience for users than standard round pads.

Plus, they are much more durable and last longer since there are no exposed wires.

All in all, I think square pads should be the go-to option for most people.

]]> Fri, 19 May 2023 23:43:28 +0000 https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post13042.html#13042 <![CDATA[Square pads standard? : In relation to the topic, I would...]]> https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12681.html#12681 Author: mhike08
Subject: 3155
Posted: 03 Nov 2022 at 6:04pm

In relation to the topic, I would like to ask if there is a disadvantages of using square pad in terms of manufacturing and solderability? 

And also for clearance and creepage? 

Thanks for the response.

]]> Thu, 03 Nov 2022 18:04:31 +0000 https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12681.html#12681 <![CDATA[Square pads standard? : For Diodes, the package polarity...]]> https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12544.html#12544 Author: Tom H
Subject: 3155
Posted: 18 Aug 2022 at 12:26pm

For Diodes, the package polarity is normally on the Cathode. 

For LEDs, the package polarity is normally on the Anode. 

Footprint Expert allows the user to manually insert polarity markings that stay save in the FPX library. 

Here are some of the shapes and the user defines the size, location, shape, rotation and layer. 


 
]]> Thu, 18 Aug 2022 12:26:24 +0000 https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12544.html#12544 <![CDATA[Square pads standard? : Diodes are a real pain in the...]]> https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12543.html#12543 Author: feynman
Subject: 3155
Posted: 18 Aug 2022 at 12:19pm

Diodes are a real pain in the ass for assemblers. Diode orientation should be made ridiculously clear:
- Draw a diode symbol or a triangle on the silkscreen (if possible).
- Draw a diode symbol on your assembly drawing.
- Name the pins "A" and "C" instead of "+", "-", "1" or "2".

If something can be remotely considered "industry standard" with diodes than it's the cathode being the "special" pin that is marked one way or the other.


]]> Thu, 18 Aug 2022 12:19:19 +0000 https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12543.html#12543 <![CDATA[Square pads standard? : Anode/Cathode polarity markings...]]> https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12542.html#12542 Author: Tom H
Subject: 3155
Posted: 18 Aug 2022 at 11:04am

Anode/Cathode polarity markings are defined by each PCB designer in cooperation with their assembly shops recommendations. 

Assembly shops should have their own DFA (Design for Assembly) handbook, but it may not contain polarity marking guidelines. 

There are some recommendations coming from IPC-7352 which should be released by the end of the year. 


]]> Thu, 18 Aug 2022 11:04:22 +0000 https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12542.html#12542 <![CDATA[Square pads standard? : Thank you. If I may ask, does...]]> https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12541.html#12541 Author: BertX
Subject: 3155
Posted: 18 Aug 2022 at 10:24am

Thank you. If I may ask, does the standard say how to mark anodes/cathodes or is this also up to the user?]]> Thu, 18 Aug 2022 10:24:06 +0000 https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12541.html#12541 <![CDATA[Square pads standard? : IPC has no guidelines for using...]]> https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12540.html#12540 Author: Tom H
Subject: 3155
Posted: 18 Aug 2022 at 8:18am

IPC has no guidelines for using Square Pad Shape to indicate Pin 1 for through-hole footprints. 

It started back in the 1970's with Bishop Graphic decals for DIP14's for hand taping and just migrated into CAD in the 1980's. 50 years ago silkscreen was rare so we used copper shapes to indicate Pin 1.
 
It's a defacto standard that is totally up to the end user to define how they want to indicate the location of Pin 1. 

]]> Thu, 18 Aug 2022 08:18:38 +0000 https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12540.html#12540 <![CDATA[Square pads standard? : I have been looking for this for...]]> https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12539.html#12539 Author: BertX
Subject: 3155
Posted: 18 Aug 2022 at 1:40am

I have been looking for this for a while now. 

Opinions seem to be divided on this. 

But does the IPC say anything on the use of square pads? 

I was always taught at school it denotes the positive lead or pin 1. 

So that would mean the anode of a diode or capacitor, but it seems most use it to indicate the cathode. 

So is there a standard for this?

]]> Thu, 18 Aug 2022 01:40:06 +0000 https://www.PCBLibraries.com/forum/square-pads-standard_topic3155_post12539.html#12539