Electronics Forum | Tue Aug 22 11:03:45 EDT 2000 | Dr. Ning-Cheng Lee
Hi Kelvin, Regarding to the surface finish of the leads, Sn or Pd may be the direction that the industry takes. First of all, the answer must be "Pb-Free", limiting our choices. Sn has good solderability, and it won't have too great of an impact o
Electronics Forum | Thu Jul 20 16:45:54 EDT 2000 | Darby
Good morning Bob. Darby from Australia here. We sometimes see an orange peel type finish on our reflow solder joints when viewed under the microscope. Any ideas on what causes this ? Should I worry about it. I use a straight rise profile ( no "platea
Electronics Forum | Thu Jul 20 14:36:57 EDT 2000 | Bob Willis
Yes there will be higher process temperatures on the currently preferred alloys of tin/silver. There are not that many companies highlighting they have the solutions although many parts will be fine. If all components meet the requirements of the IP
Electronics Forum | Thu Jul 20 12:30:29 EDT 2000 | Bob Willis
Personally I would go for one alloy it just makes it all simple to control. I have only used tin/silver and tin/copper so far with good process results. Reflow is relatively straightforward, I have had more shorts with wave on tin/copper. To date I
Electronics Forum | Wed Jun 06 10:59:43 EDT 2001 | wbu
It�s hard to tell you one good profile for a specific machine cause profiles are mainly dependent on the specific assembly you want to rework. My aproach to this problem is trying to get a close as possible profile as under normal reflow conditions u
Electronics Forum | Tue Jun 19 13:28:41 EDT 2001 | drj
Greg: Several year ago we did a lot of work to develop methods for finding reliable common profiles. The process we came up with takes an emmense amount of time, and leaves the user with an "adequate" profile for each product, rather than the "one b
Electronics Forum | Fri Jun 15 09:16:46 EDT 2001 | adam
Thanks Dave. About your second comment, the issue is placing BGA connectors mirror image (male, and female), the connector sometimes shifts during placement before reflow. we are using a six mil stencil for both sides with minimum paste deposit. a
Electronics Forum | Mon Jun 18 11:23:44 EDT 2001 | Gil Zweig
BGA defects observed with x-ray inspection fall into catagories. One catagory is the obvious defects; i.e. soledr bridges, missing balls, excessive solder voids. The second catagory is the more subtle "potential" defect. This is where variations in
Electronics Forum | Wed Jun 20 12:07:13 EDT 2001 | Steve
I would suggest getting a copy of IPC-SM-782A, Surface Mount Design and Land Pattern Standard, and IPC-7525 Stencil Design Guidelines. My experience is that reflow does not cause tombstoning very often. Pad and land design, paste volume, and placemen
Electronics Forum | Mon Jun 18 19:32:58 EDT 2001 | Gil Zweig
I believe that at the present time the industry really does not know how to use x-ray inspection apart from indentifying the obvious defects such as shorts, missing balls and gross solder voids. The real utility of x-ray inspection is to recognize: 1
A dealer of high quality Used SMT Equipment, Used Plastic Injection Molding Equipment, Used Machine Tools, Used Semiconductor Machinery, and Used Industrial Machinery.
Equipment Dealer / Broker / Auctions
104 East Street
Middleton, MA USA
Phone: 978 790-2774
