Electronics Forum | Mon Jun 07 09:28:56 EDT 1999 | John Martell
Thanks a lot,, so assuming we are using standard parts, with nothing out of the ordinary we could safely assume that a machine capable of 20 mil would be more than able to meet our needs down the road. | We are changing from through-hole to SMT, won
Electronics Forum | Tue Feb 23 09:51:35 EST 1999 | Steve Schrader
| Hey all- | | My question is this: My stencil printer operator has said that he has to | wipe our 6-mil stencil each pass to get the paste in the 20-mill pitch | aperatures for a QFP to release well. We are using Amtech NC-559 type 3 | paste with
Electronics Forum | Wed Oct 03 17:07:52 EDT 2001 | davef
We have had soldering problems with fine pitch QFP in the past [and probably will in the future]. Several questions leap to mind: * When you took your profile on the component pads, do you profile on the pads that did not solder well? * When you say
Electronics Forum | Thu Jun 21 09:02:40 EDT 2018 | spoiltforchoice
I'd be tempted to say you buy whatever is most consistent with what you paid for the rest of the machine.... And if you can source Chinese copies& they aren't expensive it can't hurt to try a few. More generally (I don't know how these particluar ma
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
Electronics Forum | Sat Oct 07 04:02:50 EDT 2000 | C.J. Long
Good morning, All: I am from PCB shop and one of our customer is experiencing solder bridge on 16 mil pitch QFP( immersion gold finish). Land width requirement is 8 +/- 1 mil measured over top of of land and our mean is 7 mil. Bottom land width is 8
Electronics Forum | Mon Jul 24 17:47:16 EDT 2000 | John Thorup
Hello Nick I'm not aware of any published 1:1 footprints. couple of options: Topline dummy show and tell display cards. $$ I believe. Since there aren't that many different pitches, get one of each and glue those puppies to a card. Could be new, dea
Electronics Forum | Wed Jan 31 01:41:00 EST 2001 | pjc
Steve, I have no influence over conn design. We paste print-reflow solder two types of connectors. One is a 50 pin IDC w/ 0.5mm lead dia @ 2.54mm lead pitch and a chamfered pointed lead tip. The other is 32 pin DIP w/ 0.36mm lead dia @ 2.54mm pitch
Electronics Forum | Mon Jun 25 21:02:42 EDT 2001 | davef
Try: 1 SMTA [http://www.smta.org] Knowledge Base Conference Proceedings: * 09/24/2000 COMPARISON OF AG, NI/AU, AND SOLDER PWB SURFACE FINISHES ON THE SECOND LEVEL RELIABILITY OF FINE PITCH AREA ARRAY ASSEMBLIES Lon E. Chase, Raytheon Electronic Syste
Electronics Forum | Mon Dec 20 12:50:27 EST 1999 | Wolfgang Busko
Hi Pascal, 0,65mm pitch normally isn�t much of a problem. With 90�m CU I don�t have any experience but would like to know what deviation from nominal value for the pads you get with different PCB-deliveries. In short, for the standard Cu=35�m we se
