Electronics Forum: stencil aperture (Page 66 of 121)

solution to design challenge (ubga, NSMD pads, heavy traces)

Electronics Forum | Wed Mar 18 11:27:24 EDT 2020 | slthomas

I am about to order a stencil and I can already see that I'm going to have issues. I'm hoping someone has a recipe for this scenario that we haven't tried yet. The parts are 16 mil pitch bga's, the pads are NSMD (10 mil dia. with 12.6 mil mask open

Type 3 vs. Type 4 solder paste

Electronics Forum | Fri Nov 10 09:13:34 EST 2006 | russ

Dave hit the cons pretty well for type 4 type 4 is used when you have extremely small apertures and type 3 will not fit into them or release adequately basically. I have not yet had application that requires it but got very close once, .007 circle

Solder balls

Electronics Forum | Thu Jul 17 15:12:18 EDT 2008 | slthomas

To quote a regular here, "Are you sure your washer is set up correctly?" :P He's a WS junkie. This is a really common problem and is discussed here often. Mid chip solder balls (solder beads) are almost always the result of too much paste being dep

stepped stencils

Electronics Forum | Thu Feb 23 18:05:53 EST 2006 | kennyg

What are some general guidelines for the minimum proximity of apertures to a stepdown on a stepped stencil. I have a step from 7 mils to 5 (one mil step each on the top and bottom). How far does the step need to extend beyond the apertures on the

Re: Tombstoning of chip capacitors

Electronics Forum | Wed Aug 25 16:42:32 EDT 1999 | Dave

| | | | | | Could use a little help here. Can anyone clarify to me the cause and fix of chip caps/resistors tombstoning following reflow? | | | | | | | | | | | | Any help would be appreciated. Thanks. | | | | | | | | | | | Most common reason is

DEK 288 machine...

Electronics Forum | Thu Sep 20 09:12:28 EDT 2001 | jschake

If you were successful in running the machine in dry cycle mode, then I would expect with new squeegees that the prints would be acceptable. To give you more tangible data on what you may expect from the actual print results, maybe you could run the

screen printer from MPM

Electronics Forum | Fri Feb 06 15:52:18 EST 2004 | pjc

SPM is superior in terms of technology and application. SPM has larger print area, up to 20� x 19", vs. 17.7� x 15.7� for the MicroFlex. MicroFlex is microprocessor controlled while the SPM has a PC. SPM can print down to 12mil (0.3mm) fine pitch no

LGA and Solderballs

Electronics Forum | Tue Nov 28 21:16:17 EST 2006 | davef

J Rose at EMPF says: The introduction of no-clean solder fluxes in electronics manufacturing has given rise to greater levels of solder balling simply because the opportunity to remove them in the wash process does not exist. They are typically cause

Pick and Place Startup - LQPF100 bridging issues

Electronics Forum | Thu Mar 25 20:50:50 EDT 2021 | stephendo

A couple more things. The PCB. What size are the pads? One time a board shop had difficulty putting masking between the pads of a QFP and the pads suffered as a result. When I told them they didn't have to have masking between the pads, the pads w

Re: uBGA Stencil Thickness

Electronics Forum | Mon Dec 21 17:50:55 EST 1998 | anamonus

| I have a mixed technology board ranging from 50 mil pitch devices to 20mil Qfp's to PBGA-352 at 1.27mm, and 6 Intel uBGA-48 at 30 mil pitch. With all these different package types i'm torn between using a 4 or 5mil thick stencil. The ball dia. is 1


stencil aperture searches for Companies, Equipment, Machines, Suppliers & Information