poor part... it possibly overheated inside as well... hopefully, not some
14 nm transistor inside of SIP.
> If heat caused the pad to come off the PCB should be blistered or
> discolored in the area and other similar pads using the same parameter so
> affected.
> I have dissolved pads and knees in a tin lead Wenesco leaving the module
> in
> for 60 seconds during a SIP replacement. It takes extreme time duration to
> cause this. It was clear that the part had been in contact with solder too
> long.
>
> The pad to laminate interface or other fabrication defect per George is
> suspect.
>
> On Fri, Nov 11, 2016 at 9:34 AM, George Wenger <[log in to unmask]>
> wrote:
>
>> Going back to a previous comment Richard made I too would never use
>> immersion tin as a PCB surface finish. My preference still is immersion
>> silver. Now to Julianos comment about a pad disappearing during
>> selective
>> wave soldering. I can't believe a pad disappearing has any thing to do
>> about immersion tin surface finish or selective wave soldering
>> parameters
>> as much as it base to do with poor PCB fabrication. I would cross
>> section a
>> pad before soldering to see what the copper thickness is
>>
>> Sent from my iPhone
>>
>> > On Nov 11, 2016, at 8:40 AM, Stadem, Richard D. <
>> [log in to unmask]> wrote:
>> >
>> > One, or many?
>> >
>> > -----Original Message-----
>> > From: TechNet [mailto:[log in to unmask]] On Behalf Of Datacom - Juliano
>> Ribeiro
>> > Sent: Friday, November 11, 2016 5:21 AM
>> > To: [log in to unmask]
>> > Subject: [TN] RES: [TN] Immersion Tin - problems
>> >
>> > Damaged = "Pad disappeared" the track has broken
>> >
>> > _____________________________
>> > Juliano Bettim Ribeiro
>> > DATACOM
>> > +55 (51) 8446-2135
>> > +55 (51) 3933-3000
>> > Ramal: 3484
>> >
>> >
>> >
>> > -----Mensagem original-----
>> > De: TechNet [mailto:[log in to unmask]] Em nome de George Wenger
>> > Enviada em: quinta-feira, 10 de novembro de 2016 17:32
>> > Para: [log in to unmask]
>> > Assunto: Re: [TN] Immersion Tin - problems
>> >
>> > What do you mean by "damaged"?  Do you mean solder doesn't wet the pad
>> or is
>> > there physical damage?
>> >
>> > Sent from my iPhone
>> >
>> >> On Nov 10, 2016, at 1:16 PM, Vladimir <[log in to unmask]>
>> wrote:
>> >>
>> >> Hi Juliano,
>> >>
>> >> The board finish most probably has nothing to do with the problem. It
>> must
>> > be your process.
>> >>
>> >> Regards,
>> >>
>> >> Vladimir
>> >> SENTEC
>> >>
>> >> Sent from my BlackBerry 10 smartphone on the Rogers network.
>> >>  Original Message
>> >> From: Datacom - Juliano Ribeiro
>> >> Sent: Thursday, November 10, 2016 13:13
>> >> To: [log in to unmask]
>> >> Reply To: TechNet E-Mail Forum
>> >> Subject: [TN] Immersion Tin - problems
>> >>
>> >> Hello to all,
>> >>
>> >>
>> >>
>> >> We recently are changing to Lead Free process to specific products
>> and
>> >> we need to change the finishes boards from (HAL Tin Lead) to
>> Immersion
>> > Tin.
>> >>
>> >> But during the Selective Soldering process the component pad is
>> damaged.
>> >>
>> >> Are there limitation about Immersion Tin about Max. Temperature, Max.
>> >> Reflow/Wave process, Max Soldering Contact Time, etc.???
>> >>
>> >> In this case the HAL Lead Free is better?
>> >>
>> >>
>> >>
>> >>
>> >>
>> >> Thank you
>> >>
>> >> Juliano Ribeiro
>>
>