Ed,

We have been having a bear of a time with the 40 pin TSOP's that you have 
mentioned.  When we contacted Intel's technical support about this, they 
said that no one has ever complained about soldering these parts.  However, 
Intel recently came out with a document detailing how the new parts 
(proposed release date November) will have copper lead frames.  We are 
hoping that this solves our problem.  If you need a copy of this paper 
please contact me.

Max Bernhardt
Woodward Governor Co.
970-962-7376
fax 970-962-7143
 ----------
From: TechNet-request
To: technet
Cc: GSPLASV
Subject: ASSY: TSOP Solder Joint Cracks
Date: Monday, October 07, 1996 5:13PM



From: [log in to unmask]
Date: Mon, 7 Oct 96 15:59:36 EDT
Message-Id: <[log in to unmask]>
To: [log in to unmask]
Sender: [log in to unmask]
Precedence: bulk

Does anyone have experience with Surface Mount Soldering plastic TSOP
packages?

We are experiencing cracks in these SMT TSOP solder joints.  The cracks
start in the heel and propagate to the toe of the solder joint.
Initialy these cracks were observed after the convection solder
operation.  We then reduced the amount of solder (6.5 mil height)
and the temperature of the solder operation (205-210 C).  Although
the solder joints looked good after the SMT process they did crack
after the subsequent wave solder process.

The leads of the TSOP device are Alloy 42 (Kovar) fine 19.7 mil pitch.
The PWB material is Multifunctional Glass (Tg 180).

Edward Karnish
Lockheed Martin Communication Systems
[log in to unmask]
phone 609-338-3182
========================================================================
To learn more about this email exploder (majordomo), including how to
unsubscribe from this list, send e-mail to: [log in to unmask]
and place the command "help" in the body of the message - subject may be
left blank. Help can also be obtained on the WWW at
http://www.epic.lmco.com/Majordomo
========================================================================

***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To unsubscribe from this list at any time, send a message to:           *
* [log in to unmask] with <subject: unsubscribe> and no text.        *
***************************************************************************

***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To unsubscribe from this list at any time, send a message to:           *
* [log in to unmask] with <subject: unsubscribe> and no text.        *
***************************************************************************