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November 9, 2017

Which term to use, PWB or PCB?

Is there any real difference between the terms Printed Wire Board (PWB) and Printed Circuit Board (PCB)? Which do you recommend we use for internal and external documents?

R. D.

Expert Panel Responses

This question has been discussed numerous times at IPC meetings and usually enables a fair amount of emotion.

All of the following are possible uses, depending on your age, geographic location (slang usage), and where/how you got your training. I'm sure there are more.

PB - printed board. the most generic term for a bare board

PWB - printed wiring board, one of the first uses when the issue was only a point to point connection.

PCB - printed circuit board, where the width, side to side and multi-layer relationship(spacing) of conductor runs has or is designed to have a specific effect on circuit operation other than just a point to point connection. Circuit impedance is a primary issue. In approximately 1999 the IPC Technical Activities Executive Committee made a mandate to only use the term PCB for all new document development because more often than not the printed circuitry design will have an impact on function.

PWA - printed wire assembly - older use

PCA - printed circuit assembly - logical to use with the 1999 change to PCB.

PCBA - printed circuit board assembly - multiple requests/comments (strong push) from users and technical committees in Asia and Europe to use this as the preferred term.

Embedded active or passive components opens up a whole new range of possibilities as well.

While it would be good to have a single term (or pair of terms for bare boards and assemblies) reality is that there are many IPC documents of various age using different terms and many more book and magazine article authors, conference lecturers, etc., that pretty much use whatever term they are most comfortable with.

If preparing a document; it would be appropriate to use a term that most of the expected users would understand. In the world of electronics technology, it would seem that most users should be able to understand the content when any of these terms are used.

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Jack Crawford
Director - Certification & Assembly Technology
IPC
Mr. Crawford is Director of Certification and Assembly Technology for IPC. He is technical liaison to the IPC committees that maintain critical industry standards and has presented numerous papers internationally.

Great question. IPC-T-50H, has a definition for each of these terms, Printed Circuit Board, provides both point-to-point connections and printed components in a predetermined arrangement on a common base. Printed Wiring Board, provides point-to-point connections but not printed components in a predetermined arrangement on a common base. There is a difference between the two, but I would say the industry has used the term interchangeably throughout the history of electronic manufacturing. Left to my devices all raw boards coming from the board shops should be called Printed Wiring Boards.

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Leo Lambert
Vice President, Technical Director
EPTAC Corporation
At EPTAC Corporation, Mr. Lambert oversees content of course offerings, IPC Certification programs and provides customers with expert consultation in electronics manufacturing, including RoHS/WEEE and lead free issues. Leo is also the IPC General Chairman for the Assembly/Joining Process Committee.

Most of the industry uses PCB. So that would be the term for me.

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Edward Zamborsky
Regional Sales Manager
OK International Inc.
Mr. Zamborsky serves as one of OK's technology advisers to the Product Development group. Ed has authored articles and papers on topics such as; Low Volume SMT Assembly, Solder Fume Extraction, SMT Rework, BGA Rework, Lead Free Hand Soldering, Lead Free Visual Inspection and Lead Free Array Rework.

No Real difference. PCB is the more modern term.

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Gary Goldberg
President and CEO
PROMATION, Inc.
Mr Goldberg has practical experience in production line layout, process flow and cycle rate analysis. He knows how to avoid bottle necks and most related PCB or pallet handling questions.

Reader Comment
It is same, PCB is used more than PWB.
Scott Chen, Excellence PCB Technology Co.,Ltd


Reader Comment
I started in the 70s calling them Printed Wire Boards and Printed Wire Assemblies as still prefer those terms. A Printed Circuit is just that, a circuit that is printed to the board with printed resistors, traces printed specifically to provide deliberate capacitive or inductive effects, or other "printed" components as in a Hybrid.

To say that "printed circuitry design will have an impact on function" negates the fact that even if all components are connected by discrete wires, those wires still impart LCR characteristics to the circuit function.

Personally I think we as an industry just got lazy and instead of continuously correcting the commonly misapplied term "Printed Circuit" we just gave up and accepted it.

Terminology is only useful if it has specific meaning and we now have ambiguous terms that don't specify exactly what we are talking about.
David Mason