Doug,
The definitions given in IPC-T-50E are as follows:
"Printed Circuit Board (PCB) - A printed board that provides both
point-to-point connections and printed components in a predetermined
arrangement on a common base. (See also "Printed Wiring Board.")"
"Printed Circuit Board Assembly - An assembly that uses a printed
circuit board for component mounting and interconnecting purposes."
"Printed Wiring Board (PWB) - A printed board that provides
point-to-point connections, but not printed components, in a
predetermined arrangement on a common base. (See also "Printed
Circuit board.")"
"Printed Wiring Board Assembly - An assembly that uses a printed
wiring board for component mounting and interconnecting purposes."
This is the set of definitions I refer to in my DFM presentations
(from a board fabricator's perspective), i.e., a PCB can contain more
than just point-to-point interconnections. I've interpreted the
phrase 'printed components' to mean such things as:
1) tight tolerances on line widths and dielectric spacings to achieve
specified (measured) impedance, inductance and resistance values;
and,
2) embedded components such as resistive layers, capacitance cores,
etched inductor coils, etc.
Many of today's multilayer PCB's are indeed active components in a
finished electronic assembly and no longer just passive PWB's.
Dave Wolf
HADCO Corp.
______________________________ Reply Separator _________________________________
Subject: Re: PWB and PCB???
Author: [log in to unmask] at SMTPLINK-HADCO
Date: 10/21/96 12:29 PM
At the IPC, we try to use PWB and PCB exactly as you have assumed. But,
judging from the phone calls I get, the industry has not "standardized"
on these terms.
Kim Sterling
Director, Market Research
IPC
Phone 847/509-9700 ext 305
FAX 847/509-9798
E-Mail [log in to unmask]
On Mon, 21 Oct 1996, Doug McKean wrote:
> Is there a difference between a
> PWB - Printed Wiring board and
> PCB - Printed Circuit Board
> in the industry?
>
> Is it safe to assume (uh-oh) the PWB is the bare board and
> the PCB is the PCB w/components, i.e. a PCB assembly?
>
> Does anyone out there make a strict division between the two this way?
>
> *******************************************************
> Doug McKean
> [log in to unmask]
> -------------------------------------------------------
> The comments and opinions stated herein are mine alone,
> and do not reflect those of my employer.
> -------------------------------------------------------
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