The PWB and PCB are often used interchangeably, both essentially meaning the 
same thing -- a bare board. The populated board is often referred to as a PWA 
(for printed wiring board assembly) or CCA (for circuit card assembly).The 
origin of the PWB term is, I believe, coming from the fact that boards were 
wired using discrete wiring (as a lab board), and replaced later with the copper
traces (PWB). A true printed circuit board (PCB) is more a microcircuit term 
where a part such as a resistor is deposited on a ceramic substrate. Now for a 
little philosophy, most circuits today are quickly becoming printed circuit 
boards since trace length, routing, and proximity to neighboring traces directly
influence the circuit performance directly. Power Supply and Analog Boards have 
several requirements, such as guard circuits, proximity to a component pin 
placed on them by circuit designers. The traces are acting as discrete 
components in the same way a resistor or capacitor does. 

______________________________ Reply Separator _________________________________
Subject: PWB and PCB???
Author:  [log in to unmask] at SMTPpost
Date:    10/21/96 12:29 PM


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?
     
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Doug McKean
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The comments and opinions stated herein are mine alone, 
and do not reflect those of my employer. 
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