PCB Libraries, Inc. | https://www.pcblibraries.com/forum/RSS_spacing-of-adjacent-holes_topic2044.xml
0.50 mm (20mil).This translates into hole to hole clearance, or hole to hole spacing.I don't have access to IPC-2221B which is the current rev as of November 2012
PCB Libraries, Inc. | https://www.pcblibraries.com/Forum/intent-of-applicable-documents-in-ipc2221_topic2986_post11908.html
:25am Hi all, IPC-2221B has a bunch of "applicable documents" (about 65 listed). The text heading this list says "The following documents form a part of this document to the extent specified herein
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/intent-of-applicable-documents-in-ipc2221_topic2986_post11908.html
:25am Hi all, IPC-2221B has a bunch of "applicable documents" (about 65 listed). The text heading this list says "The following documents form a part of this document to the extent specified herein
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/intent-of-applicable-documents-in-ipc2221_topic2986_post11907.html
:25am Hi all, IPC-2221B has a bunch of "applicable documents" (about 65 listed). The text heading this list says "The following documents form a part of this document to the extent specified herein
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/topic2986&OB=ASC.html
:25am Hi all, IPC-2221B has a bunch of "applicable documents" (about 65 listed). The text heading this list says "The following documents form a part of this document to the extent specified herein
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/intent-of-applicable-documents-in-ipc2221_topic2986.html
:17pm I'm thinking the phrase "to the extent specified herein" means that it's only if IPC-2221B calls out a specific requirement from one of those standards
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/ipc7251_topic1798.html
: IPC-2221B calculation formula is: Land size, minimum = Hole size + 2*Min. annular ring(Min 0.05mm) + fabrication allowance IPC-7351C calculation formula will be: Pad diameter = Hole size + 2*Min. annular ring(Min 0.2mm) , or = Hole size
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/topic1798&OB=DESC.html
: IPC-2221B calculation formula is: Land size, minimum = Hole size + 2*Min. annular ring(Min 0.05mm) + fabrication allowance IPC-7351C calculation formula will be: Pad diameter = Hole size + 2*Min. annular ring(Min 0.2mm) , or = Hole size
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/ipc7251_topic1798_post7361.html
: The calculation formula below for pad diameter is different with IPC-2221B 9.1.1, how to set "pad to hole ratio" and "minimum annular ring"? http
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/spacing-of-adjacent-holes_topic2044_post8378.html
. I don't have access to IPC-2221B which is the current rev as of November 2012. Can someone post whether the value has changed in IPC-2221B
