Electronics Forum | Wed Aug 18 21:03:41 EDT 1999 | Dave F
| | | | | One of the DFM suggestions I've seen is to remove the solder mask web, i.e. the mask between pads on 20-mil QFP devices. The rational is that if the mask is thicker than the pad the mask can prevent the stencil from making intimate contact
Electronics Forum | Tue Aug 03 17:28:33 EDT 1999 | DLKearns
| | | I have been asked to supply a maximum shelf life for our assemblied PCB's. I realise this is dependent on so many factors- temperature, humidity, no of layers etc. But does anyone have a formulae for calculating shelf life, or does anyone know
Electronics Forum | Tue Jul 27 11:32:01 EDT 1999 | M.L.
| | Presently protos of micro-bgas (80i/o) pitch .030/.031 | | 12BGA per assembly | | | | The board is a (.062, 4 layers) FR-4 using Dry film | | Pads .014inch | | Vias within footprint .020inch | | Vias to be filled by bottom side(solder side) only
Electronics Forum | Tue Jul 13 19:00:29 EDT 1999 | JohnW
| Hi All, | Does any one experienced the solder on gold finger after | reflow. Its about 5 to 8 mils diameter . | We'd clean the entire screen printer, mounter & reflow as well, | but doesn't help much. | | Mr Kong..... Solder on gold is a age old
Electronics Forum | Wed Jul 14 10:58:25 EDT 1999 | Upinder Singh
| | Hi All, | | Does any one experienced the solder on gold finger after | | reflow. Its about 5 to 8 mils diameter . | | We'd clean the entire screen printer, mounter & reflow as well, | | but doesn't help much. | | | | | Mr Kong..... | | Solder
Electronics Forum | Tue Jun 29 16:03:57 EDT 1999 | Dave F
snip | John and Dave, | | Again, I don't work with larger chip devices with this issue. The company I now work with developed a strategy, based on considerable research (as others of us did in the past), to do things like placing 0603's on 0402 pad
Electronics Forum | Fri Jun 18 14:06:15 EDT 1999 | John Thorup
| | Now don't everyone jump on this at once, but it seems time for me to send out copies of my not even close to being dated copy of an article about HASL. Though it was published in 1992, in Printed Circuit Fabrication Magazine, and it got rave revi
Electronics Forum | Thu Jun 17 20:48:18 EDT 1999 | Earl Moon
| | first of all what is the technical term for the small amount of solder on a plated pad. we are getting poor screen printing gasketing on a 20 mil qfp due to this solder not being even or too high in spots and not covering the length of the pads.
Electronics Forum | Thu Jun 17 21:24:32 EDT 1999 | Dean
| first of all what is the technical term for the small amount of solder on a plated pad. we are getting poor screen printing gasketing on a 20 mil qfp due to this solder not being even or too high in spots and not covering the length of the pads. an
Electronics Forum | Wed Jun 16 14:06:01 EDT 1999 | Jagman
| | | | A potential customer of our is inquiring if we have capability | | | | for Hot Bar manufacturing in the PCBA manufacturing world. If someone can explain to me what this entails, I would greatly appreciate it. Thank you. | | | | | | | One
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