PCB Libraries Forum Homepage
Forum Home Forum Home > PCB Footprint Expert > Questions & Answers
  New Posts New Posts RSS Feed - No Option For Pad Round-off In V2021 Edition?
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

No Option For Pad Round-off In V2021 Edition?

 Post Reply Post Reply Page  <12
Author
Message
Tom H View Drop Down
Admin Group
Admin Group
Avatar

Joined: 05 Jan 2012
Location: San Diego, CA
Status: Offline
Points: 5239
Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 09 Apr 2021 at 8:36am
The Land Pattern Naming Convention must have 3 places because of the way it was designed and created. 

XX.XX for the values. 2 places to the left of the decimal point and 2 places to the right of the decimal point. 

I guess you didn't understand 2 X 2 Decimal Place Accuracy like you set in the Console Options. 

Was this the problem that wasn't really a problem? 

When you select Decimal Place Accuracy to 2 min and 3 max, it still produces the same footprint name because that is the standard naming convention. 

i.e.: you can't change the naming convention regardless of your Decimal Place Accuracy because the naming convention is a standard XX.XX for now according to IPC-7351. 

Note: all leading zero's "0" are dropped and ending zero's are not.

Stay connected - follow us! Twitter - LinkedIn
Back to Top
Quist View Drop Down
New User
New User


Joined: 21 Jun 2018
Status: Offline
Points: 3
Post Options Post Options   Thanks (0) Thanks(0)   Quote Quist Quote  Post ReplyReply Direct Link To This Post Posted: 09 Apr 2021 at 11:07am
Ah, no I was not referring to the Naming Convention but rather to the actual pad dimensions presented under Footprint -> Manufacturer's Dimensions.
I got the impression that no matter what decimal accuracy I put in I got three decimal places on the dimensions but now I can't reproduce the behaviour so it was probably user induced...
I see in our fpx library that we have a different number of decimal places on the pads for different components. That might have been whats fooled me.

Can you please comment on the subtitle "Manufacturer's Dimensions". Who is Manufacturer referring to, component manufacturer or PCB manufacturer? I find it a bit confusing.
Wouldn't it be better to call it something like "Pad dimensions" and the checkbox something like "Use custom dimensions" or similar?

Back to Top
Tom H View Drop Down
Admin Group
Admin Group
Avatar

Joined: 05 Jan 2012
Location: San Diego, CA
Status: Offline
Points: 5239
Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 09 Apr 2021 at 11:42am
The Manufacturer reference is the Component Manufacturer, not the fabrication or assembly shops. 

The current pad stack and footprint naming conventions are intentionally created in 0.01 mm increments because if you added one more place to accommodate 0.001 accuracy, the footprint name would be too long for most CAD tools. 

Right now, the character limit for a footprint name is 40 characters. If you added one more number to each value the footprint name would be 47+ characters. 

Body Length X Width X Height X Lead Width X Length X Thermal Tab Width X Length 

Same with Pad Stack names. 

Stay connected - follow us! Twitter - LinkedIn
Back to Top
Quist View Drop Down
New User
New User


Joined: 21 Jun 2018
Status: Offline
Points: 3
Post Options Post Options   Thanks (0) Thanks(0)   Quote Quist Quote  Post ReplyReply Direct Link To This Post Posted: 09 Apr 2021 at 12:34pm
I agree, 0.01 mm is good for naming no matter what the physical accuracy is. I even seriously doubt that there is any practical benefit with going below 0.01 accuracy. Normal trace tolerance in an etch proces is probably around 0.05 mm and might be tweaked down to 0.02 mm.

Regarding "Manufacturer's Dimension": If I open a part in Footprint Expert and would like to see the size of the pads calculated by Footprint Expert the only way I know to do it is to go to the "Manufacturers Dimensions" section and look there. However, this is not the manufacturers dimensions but rather the dimensions calculated by Footprint Expert. 

I don't think the naming is intuitive.

Back to Top
Tom H View Drop Down
Admin Group
Admin Group
Avatar

Joined: 05 Jan 2012
Location: San Diego, CA
Status: Offline
Points: 5239
Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 09 Apr 2021 at 1:20pm
The pad stack naming convention used in Footprint Expert is available for free download on www.pcblibraries.com/downloads

In Footprint Expert you can double click (or single click + RMB > Properties) any pad and the program will open the pad Properties. 



If you select the Pas Stack name, it will open the Pad Stack Manager. 



The values are grayed out for any Calculator footprint because if you edit it, PCB Libraries, Inc. or IPC cannot be responsible for any typos. 

But you can visually see the pad length and width and corner radius too. 

I can look at any pad stack name and tell you the length, width and corner radius. 

You can control the corner radius in Options > Pad Stack Rules > SMD Corner Rounding > Corner Size Limit 

The default is 0.25 but many users change that value to 0.10 or 0.05. 

Stay connected - follow us! Twitter - LinkedIn
Back to Top
arendhagedoorn2 View Drop Down
New User
New User


Joined: 16 May 2015
Status: Offline
Points: 3
Post Options Post Options   Thanks (0) Thanks(0)   Quote arendhagedoorn2 Quote  Post ReplyReply Direct Link To This Post Posted: 16 May 2021 at 11:24pm
Hi Tom,
I've read all the posts about this issue but there is not realy a solution for the now missing pad round off. Is it not possible to implement the pad round off just like it was in the previous versions?:



Thank you and best regards,
Arend
Back to Top
Tom H View Drop Down
Admin Group
Admin Group
Avatar

Joined: 05 Jan 2012
Location: San Diego, CA
Status: Offline
Points: 5239
Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 17 May 2021 at 12:25pm
We're taking a look at adding the Plated Through-hole pad size round-off in V2021.05 this week. 

The default value will be set to 0.01 but you can change it to whatever value you want. 

Thanks for the input. 

Stay connected - follow us! Twitter - LinkedIn
Back to Top
Jeromeli View Drop Down
Active User
Active User


Joined: 10 Jun 2021
Status: Offline
Points: 12
Post Options Post Options   Thanks (0) Thanks(0)   Quote Jeromeli Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jun 2021 at 10:42pm
So is there a solution to this problem? Maybe we need to wait for a higher version?
Back to Top
Tom H View Drop Down
Admin Group
Admin Group
Avatar

Joined: 05 Jan 2012
Location: San Diego, CA
Status: Offline
Points: 5239
Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 17 Jun 2021 at 8:18am
We added through-hole pad and hole size roundoff feature in V2021.08. 

Look in Tools > Options > Terminals > Through-hole

Change the values to whatever you want. 


Stay connected - follow us! Twitter - LinkedIn
Back to Top
Tom H View Drop Down
Admin Group
Admin Group
Avatar

Joined: 05 Jan 2012
Location: San Diego, CA
Status: Offline
Points: 5239
Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 02 Mar 2022 at 11:36am
The latest V2022.03 release has a new Options feature for Pad Size Rounding. 

2 = 0.01 round-off
3 = 0.001 round-off

If you want a 0.05 round-off, select and open the Footprint panel and select "Use mfr. recommended pattern" and change the pad size to whatever you want. This process only takes 30 seconds. 

Note: IPC has no guidance on SMD pad size rounding. So, when you apply a 0.05 mm SMD pad size round-off, it's not IPC compliant per the 3-Tier Density Levels defined in the IPC-7351 guideline. 

Using a SMD pad Size Round-off of 0.05 mm cannot be classified as an IPC compliant pattern. 

The Pad Stack Naming Convention is in 0.01 mm increments. 

Stay connected - follow us! Twitter - LinkedIn
Back to Top
 Post Reply Post Reply Page  <12

Forum Jump Forum Permissions View Drop Down



This page was generated in 0.063 seconds.