Many thanks to Jeff and Gary for catching the discrepancy and passing the
corrected information along to all.---John


At 10:32 AM 3/6/97 -0600, you wrote:
>I'm not with IPC but I have in front of me IPC-SM-782A Amendment 1 which
>was recently released ... There was a correction to IPC-SM-782A section
>3.6.2.2 stating a width and length for the necked-down area of 0.25mm
>(0.010") and 0.50mm (0.020") respectively.
>
>As Gary mentioned, I have also _heard_ "the trace should not be larger than
>50% of the pad width" but I don't remember ever seeing that in print by
>anyone.
>
>-Jeff-
>
>At 06:37 AM 3/6/97 -0600, Tomas Garman wrote:
>>John;
>>
>>Your reference is correct, but I believe it is a typo in IPC-SM-782.
>>.025mm would be .001in the statement in 782 is  "Maximum conductor width
>>should be .025mm [.010in]"
>>
>>Would someone from IPC like to clarify? I believe the .010in figure is
>>closer to reality.
>>
>>Regards
>>Tom G.
>>
>>On Mar 6,  6:16am, john balchunas wrote:
>>> Subject: Re: SMTTraces
>>> >Date: Wed, 05 Mar 1997 09:02:11
>>> >To: [log in to unmask] (Mike Modrzejewski)
>>> >From: john balchunas <[log in to unmask]>
>>> >Subject: Re: SMTTraces
>>> >
>>> >Hello Mike, I came across the following info in Surface Mount Design and
>>> Land Pattern standard IPC-SM-782A section 3.6.2.2..."Wide conductors
>>> connecting to a land area can act as a solder thief...Narrow the conductor
>>> as it enters the land area.  Maximum conductor width should be .025
>>> mm....The minimum conductor length should be .025 mm."  Hope this helps!
>> John
>>> >
>>> >
>>> >At 06:54 AM 3/4/97 CST, you wrote:
>>> >>
>>> >>
>>> >>Hi my name is Michael Modrzejewski
>>> >>Iam looking for some information on trace width going into SMT pads.
>>> >>Is there any problems with a .025 trace going into a 1206,0805 or 0603
>pads
>>?
>>> >>IS there a rule of thumb for this ?
>>> >>
>>> >>MOJO
>>>-- End of excerpt from john balchunas
>>-- 
>>Tom Garman KC4WAR
>>PCB Designer and Librarian
>>Sacred cows make the best hamburger (stolen from a friend)
>>Don't force it, get a bigger hammer.
>>
>
>
>+ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +
>| Jeff Foster                                         [log in to unmask]    |
>| Engineering Assistant                                                     |
>| Broadcast Electronics, Inc.                         http://www.bdcast.com |
>+ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +
>
>

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