Electronics Forum | Wed Sep 18 19:43:12 EDT 2002 | dragonslayr
One more variable I've remembered - pad height with respect to solder mask height. Pads being too low can cause stencil "gasketing" problems that in turn allow more paste to be deposited than needed. Are your fabs HASL or some other media?
Electronics Forum | Sat May 03 00:58:51 EDT 2003 | ken
Did you check if the height of solder mask between two pads is higher than pads?
Electronics Forum | Mon Sep 19 21:35:54 EDT 2016 | shriram
Appreciate your suggestion. NSMD pads are used for this design, the anomalies we found are 1. the trace running between pads has a lesser solder mask height compared the other area of the pads. 2. the NSMD pads doesnot have a trench close to pad e
Electronics Forum | Mon Aug 14 05:45:16 EDT 2023 | dimamalin
First, this is the result of bad printer setup. Adjust knife pressure, PCB gap, separation speed, tooling, and stencil cleaning. Pay attention to the coating of contacts pad and height of solder mask of PCB.
Electronics Forum | Thu Aug 21 08:33:09 EDT 2008 | davef
There is no standard as such. It's easy to see why. It's too complicated and has such a small payoff. Standoff is comprised of: * Package height * Solder thickness between the pad and the component lead * Delta of pad thickness and solder mask For p
Electronics Forum | Wed Oct 03 09:56:51 EDT 2001 | Claude Tremblay
Hello everyone We have a QFP-308 (0.20" pitch)on a board and we have a lot of opens after reflow. We checked our profil by installing thermocouples on the pads of the component and everythings seems OK. We checked the coplanarity of the leads and it
Electronics Forum | Wed Apr 11 20:58:12 EDT 2018 | jacobidiego
YES to the first question in some points of the board. Bulky, to the second question when it is not in short. What you say about the PAD height, helped me to understand why the SPI shows weird values for other measurements. I am currently doing test
Electronics Forum | Mon Jul 24 10:15:23 EDT 2006 | slthomas
Set-down height to low, iow, parts getting squashed too deeply into the paste. No mask between pads on fine pitch. Pads too wide for the pitch.
Electronics Forum | Tue Jun 13 21:57:01 EDT 2000 | Dave F
Todd: You say: "... solder masking between the lands of fine pitch components can cause stenciling problems and or manufacturing problems." I say: Fine pitch components without solder masking between the lands can cause stenciling problems and o
