(1) 1 oz become 0.5 oz---> over heating (too much current going through
smaller cross section).. over current..(burn out in extreme cases...depend
upon the design safty factor used ...)..Mechanically, the PWB is thinner--->
potential loss contact on ZIF connector on the edge (loss spring force)..may
have potential viberational failure on the final assembly causing
intermittant...
(2) 0.5 oz become 1 oz---> too thick of board may result over stress the
connector on edge (I had experience the board of later rev. is thicker than
the socket I was use on one of our test instrument... it finally "jamed"
in..almost split the socket...(the vendor said the early version is obsolete
and "take it or leave it".. I would not accept on any of product...but test
instrument... you just have to do for mean time...but I don't think I'll buy
new one on the same make)...The board may be also too rigid...mess up the
allowed deformation prediction (sometime, you need flexibility)...
(3) it is important for PWB build per design. I would not use someone swarp
1 oz and H oz as a vendor...(all the thermal analysis, mechanical analysis,
computer model, qualification by similarity prediction are all "out in the
air".. you just get rid of 40% of the design analysis...I know someone else
think I am over cautions...)...
jk
At 07:10 AM 9/13/99 +0200, you wrote:
>IMO,
>
>Incoming material should be checked, there is small devices to check copper
>thickness
>
>If not detected with incoming.. then when etching the result will show
>either not completely etched.. which leads to suspicion of incorrect copper
>thickness, or over etched leading to same. In both cases we are in trouble,
>both the manufacturer and the supplier..
>
>Then UN will send US militaries .... oups... no, Manufacturer's lawyer will
>contact supplier's lawyer... we will likely end up like grown ups settling
>the matter through our quality specialist that will ask for guarantees that
>it won't be possible to happen in the future ... and get substancial credit
>note over some more material... if this is a repeat, then you won't be the
>supplier of this PCB manufacturer...
>
>I have an other question to you...
>
>What are the copper thicknesses that are available on the market today ?
>
>0.125 oz
>0.250
>0.5
>1.0
>2.0
>3.0
>???
>
>
>----- Original Message -----
>From: Wang, William (Suzhou Laminate) <[log in to unmask]>
>To: <[log in to unmask]>
>Sent: Monday, September 13, 1999 3:39 AM
>Subject: [TN] PCB use 1 OZ & H OZ copper
>
>
>> I work for a copper clad laminate company. What will happen if I
>> send wrong copper foil thickness laminate to PCB fabricator?
>> 1. Customer require 1 OZ on both sides, but I send o.5 OZ on both
>> sides
>> 2. Customer require 0.5 OZ on both sides, but I send 1 OZ on both
>> sides
>> It's just a scenario analysis.
>>
>> Thanks and best regards
>> William
>> QA Manager
>> ISOLA Laminate Systems Suzhou
>>
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