TECHNET Archives

July 2001

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
"<Peter George Duncan>" <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Mon, 2 Jul 2001 09:12:51 +0800
Content-Type:
text/plain
Parts/Attachments:
text/plain (78 lines)
Hi, Jonathan,

Your temperatures seem very high and your 180 C duration is long compared
with what I'm used to using - what sort of boards and what sort of solder
are you using? What components are failing? More details, please.

Have you made sure that the maximum case temperature of any of your
components (especially the failing ones) is not being exceeded?
Have you also made sure that, if any of the components are moisture
sensitive, they are either within their moisture exposure limits or have
been baked out prior to assembly and soldering?
If you're sure everything else is OK and all that you're left with is the
reflow cool-down rate, I would go for about 4 C per minute.

Pete Duncan




                    Jonathan A Noquil
                    <Jonathan.A.Noquil@FAIRCHIL        To:     [log in to unmask]
                    DSEMI.COM>                         cc:     (bcc: DUNCAN Peter/Asst Prin Engr/ST Aero/ST Group)
                    Sent by: TechNet                   Subject:     Re: [TN] Cooling Rates
                    <[log in to unmask]>


                    06/28/01 07:40 PM
                    Please respond to "TechNet
                    E-Mail Forum."; Please
                    respond to
                    Jonathan.A.Noquil






Hello Guys,

 What is the best cooling down rate in a reflow oven?
 Does anybody have experience on what maximum cooling down rate
that will not result in Silicon cracking?
We have some silicon cracking (Chips) and we are still evaluating
if fast cool down can cause this problem.
My Profile is:
Pre-heat: 150 C
Soak: 250 C
Reflow 1: 290 C
Reflow 2: 290 C
Time of Reflow: 180 secs

Thank you very much in advance for your ideas tomorrow

---------------------------------------------------------------------------------

Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
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 delivery of Technet send the following message: SET
Technet NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail 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 1.8d
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 delivery of Technet send the following message: SET Technet NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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
---------------------------------------------------------------------------------

ATOM RSS1 RSS2