Following is one of reasons cause Tombstone:
    - Vertial shifted part: Mounting condition is NG
    - Not same solder paste volume at two sides of part: Printing condition
is NG.
    - Temperature at two electrodes of part is different: when PCBA going
through reflow machine, one electrode
       of part will be heated and smell first -- > tombstone
Best regard.

----- Original Message -----
From: "Suganthi" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, May 10, 2005 2:51 PM
Subject: [TN] Tombstone



Dear All,

What is called Tombstone effect ,please explain me , and tell me how to
overcome this problem..

Thanks and Regards

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Suganthi

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