Aric,

Why did you pick a Urethane over a silicon or epoxy?
We use the 85/85 because our device is packaged similar to a IC. Its
dimensions are 1"x 0.5" x 0.5" (L x W x H). Most IC manufacturers use
this 85/85 test setup.

The above comments are of my own opinion, and
not necessarily that of my employer.

http://www.hadco.com:8080

Dave Hoover (aka, Groovy)
NPI Mgr HADCO TC2
Watsonville, CA

>From: Aric J Parr <[log in to unmask]>
>To: David Hoover <[log in to unmask]>
>Subject: Re: [TECHNET] ASSY:PCB Assy that is Potted
>Date: Thursday, October 16, 1997 5:44 AM

>     How hot is the iron used to solder the pins. A hot iron (or
>excessive
>     contact time) could lift traces/delaminate solder mask.We use
>MetCal Irons which are supposed to self regulate the temperature and
>avoid this problem.
>     
>     Also, how clean is the PCB prior to solder mask adhesion. It could
>be
>     a PCB fab issue.We check the fabs of every lot with a ionograph.
>Readings have never exceeded 5ug. on any lot.
>     
>     We assemble, solder terminals and pot (with Urethane) large
>quantities

>     of units each year, and don't have this particular problem,
>although
>     85/85 is not a normal test condition.What test conditions do you
>use?