PCB Libraries Forum Homepage
Forum Home Forum Home > Libraries > Footprints / Land Patterns
  New Posts New Posts RSS Feed - Do we haev a new release of IPC-7351?
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Do we haev a new release of IPC-7351?

 Post Reply Post Reply Page  <123
Author
Message
tgrodnicki View Drop Down
Advanced User
Advanced User


Joined: 30 Sep 2014
Status: Offline
Points: 87
Post Options Post Options   Thanks (0) Thanks(0)   Quote tgrodnicki Quote  Post ReplyReply Direct Link To This Post Posted: 06 Dec 2022 at 11:24pm
I noticed that IPC-7352.opt is in my Footprint Expert 2022 Pro folder, but not in my Footprint Expert 2022 Enterprise folder.

Maybe it's the same for other users.

Back to Top
dramos View Drop Down
Active User
Active User


Joined: 18 Feb 2021
Status: Offline
Points: 43
Post Options Post Options   Thanks (0) Thanks(0)   Quote dramos Quote  Post ReplyReply Direct Link To This Post Posted: 07 Dec 2022 at 4:23am
Hi,
 
@tgrodnicki, I installed the Footprint Expert 2022 Enterprise Edition (2022.15,12/2/2022). There was the 7352.opt file.  I hope it will help you.

@Tom, I checked the 7352.opt and as you mentioned the fabrication and assembly tolerances are 0.00. Now we cannot find a negative value on the solder joint tables.
But what about the naming convention? Is there any change? Does the new standard continue with the same naming convention that was used on 7351-B?

Waiting to have the possibility to read the new standard.

Best regards,
David
Back to Top
Tom H View Drop Down
Admin Group
Admin Group
Avatar

Joined: 05 Jan 2012
Location: San Diego, CA
Status: Offline
Points: 5301
Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 07 Dec 2022 at 9:50am
The IPC-7352.opt file was missing from one of our program installers. 

That was fixed and all versions now have that Option file. Footprint Expert will still follow the IPC-7351 mathematical model until if and when the industry accepts IPC-7352, which may take a year or so. But at least we have a workaround in the meantime. 

It's important to note that when you open the IPC-7352.opt file to immediately save as another name because the Enterprise will overwrite the IPC-7352.opt file with every update. 

V23.01 will be released the first week of January 2023 and it will support the new IPC-7352 Footprint Naming Convention in the Console Options. 

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


Joined: 18 Feb 2021
Status: Offline
Points: 43
Post Options Post Options   Thanks (0) Thanks(0)   Quote dramos Quote  Post ReplyReply Direct Link To This Post Posted: 02 Jan 2023 at 2:03am
Dear Tom and Team,

Firstly, Happy New Year! All the best for the new 2023.

I have just installed the new version of Footprint Expert. I realized that the naming convention is quite similar to the defined in IPC-7351B. 

I need to read the new IPC-7352 to find the differences with the old IPC-7351B about the naming convention but could you advance something about it? Where was the issue to use the proposed naming convention by Footprint Library Expert? what about the zero component orientation position? is it according IPC-7351B or IEC 61188-7?

Regards,
David
Back to Top
Tom H View Drop Down
Admin Group
Admin Group
Avatar

Joined: 05 Jan 2012
Location: San Diego, CA
Status: Offline
Points: 5301
Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 02 Jan 2023 at 10:04am
In V23 Footprint Expert "Console Options" there is a dropdown menu for 3 naming conventions:
  • IPC-7351B
  • IPC-7352
  • PCB Libraries
The PCB Libraries naming convention was originally voted on and approved for IPC-7351C. 

The biggest difference between PCB Libraries and IPC-7352 is the location of the Pin Qty. 

PCB Libraries (IPC-7351C) the pin qty is in the beginning of the footprint name after the component family. 

IPC-7352 the pin qty is at the end of the footprint name (just like IPC-7351B). 

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: 5301
Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 02 Jan 2023 at 10:45am
The IEC 61188-7 Zero Component Orientation standard just reset the Pin 1 location to Lower Left, just like it was for 18 years under the IPC-SM-782 standard. 

The IPC-7351B Pin 1 orientation in the Upper Left was a last minute change that should have never been adopted. 

IEC did not agree with the 2005 release Zero Component Orientation introduced in IPC-7351 so in 2007 IEC released IEC 61188-7 to correct the Zero Component Orientation back to what is was in IPC-SM-782. 

The IPC 1-13 Land Pattern committee never got a chance to vote on or approve the new Zero Component Orientation in IPC-7351. It was just slipped in at the last minute. 

This was a huge mistake by the 1-13 Land Pattern Committee chairman to approve this change. 

All rectangular component packages should be rotated to make the long direction "Horizontal" for many reasons. Your computer screen is long in Horizontal. Paper sizes are long in Horizontal. Most PCB designs are long in horizontal. This was never discussed in the final meeting where all the rectangular footprints were changed to the length in the Vertical direction. 

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


Joined: 18 Feb 2021
Status: Offline
Points: 43
Post Options Post Options   Thanks (0) Thanks(0)   Quote dramos Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jan 2023 at 4:23am
Dear Tom,

Many thanks for your replies. 

Starting from the end. It has a lot of sense to work with a footprint in a "horizontal" way instead of "vertical" way. Perhaps in a new revision of the standard (in the next 15 years) it will be taken into account.

About the naming convention, I found another difference  comparing two footprints, the lead size is not defined.
IPC-7352 : QFN50P500X400X80-28N
PCB Libraries: QFN28P50_500X400X80L40X25N

I think that it could be useful in some cases. It gives more info about how it is the component. 
The final pad length depends of the component's lead size.

Regards,
David
Back to Top
Tom H View Drop Down
Admin Group
Admin Group
Avatar

Joined: 05 Jan 2012
Location: San Diego, CA
Status: Offline
Points: 5301
Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jan 2023 at 9:38am
The IPC-7352 only adds the Terminal Length in Gull Wing leaded packages (not flat lead packages). 

People ask me which Land Pattern Naming Convention is the best? 
  • IPC-7351
  • IPC-7352
  • PCB Libraries
I say PCB Libraries naming convention. We thought of everything to remove duplication of footprint names. 

All IPC documents for PCB design have been downgraded from "Standards" to "Guidelines". 

About 50% of all PCB designers don't use IPC documents for PCB design. The other 50% use IPC documents as a guideline but eventually develop their own standards. 

IPC is slowly pulling away from PCB design and focusing on Assembly and Fabrication. IPC J-STD-001 is the leading standard for Assembly Acceptability. All footprints should be IPC J-STD-001 compliant. 

IPC pulled the CID and CID+ training courses. They do have courses on Fabrication and Assembly. 


Select any of the buttons and you will not find any PCB design certification. 

Stay connected - follow us! Twitter - LinkedIn
Back to Top
 Post Reply Post Reply Page  <123

Forum Jump Forum Permissions View Drop Down



This page was generated in 0.063 seconds.