Hi Werner,

Whats the best way to measure the T of the BGA package?
What I've been trying is to tape down a TC on the top of the chip with
Kapton.
But my concern is whether the air temp coming from the nozzles will affect
the readings registered by the TC.
I've run the board a few times, with varying amounts of layers of kapton
used to hold the chip down, and it has affected the reading of that TC, and
it also lowers the maximum temperatures recorded by TC's under the chip.

How do you work around, or interpret the numbers you may get?

Toby


> -----Original Message-----
> From: Werner Engelmaier [SMTP:[log in to unmask]]
> Sent: Friday, November 08, 2002 3:33 PM
> To:   [log in to unmask]
> Subject:      Re: [TN] profiling BGAs
>
> Hi robert,
> You need to drill the hole into the PCB pad and place the thermocouple
> inside
> the solder joint/ball/column. You need to measure the T of the solder
> joints,
> not the air space underneath the BGA nor the PWB. At the very least, the T
> of
> the BGA should be measured.
>
> Werner Engelmaier
> Co-Chair, IPC-7530 "Guidelines for Temperature Profiling for Mass
> Soldering
> Processes (Reflow & Wave)" Task Group
>
> ---------------------------------------------------
> Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
> To unsubscribe, send a message to [log in to unmask] with following text in
> the BODY (NOT the subject field): SIGNOFF Technet
> To temporarily halt or (re-start) delivery of Technet send e-mail to
> [log in to unmask]: SET Technet NOMAIL or (MAIL)
> To receive ONE mailing per day of all the posts: send e-mail to
> [log in to unmask]: SET Technet Digest
> Search the archives of previous posts at: http://listserv.ipc.org/archives
> Please visit IPC web site http://www.ipc.org/html/forum.htm for additional
> information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
> ext.5315
> -----------------------------------------------------

---------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/html/forum.htm for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
-----------------------------------------------------