Electronics Forum | Thu Feb 24 00:37:08 EST 2022 | joshsvoboda
I have a pcb with an ENIG finish that is using a 144 pin LQFP and being soldered withSN100C/NC258 T4 paste. I used a oven profiler where the probes are taped down to the joint and the profiling software adjusts the program for the best profile for
Electronics Forum | Tue Apr 24 09:19:51 EDT 2018 | vetteboy86
Is there a preferred method among printed circuit board assembly for accurately and quickly verifying the copper weight of a printed circuit board? I would like a tool and process that our quality inspector could quickly use to verify upon receipt of
Electronics Forum | Tue Mar 24 13:21:16 EST 1998 | Earl Moon
| Should I use thermals or direct connects on | vias from BGA pads to power planes. The via is | connected to the BGA pad via a short 8mil trace. Thermals are safest. However, I have had no problems using direct connects provided parameters are capab
Electronics Forum | Fri Jun 16 10:38:33 EDT 2000 | Iain
I have 15 very large backplanes (.156" thick Au plating) that the ground pins of a high density thru-hole connector were not thermal relieved in the artwork. As a result we are unable to solder the 8 pins that connect to the ground plane. We know t
Electronics Forum | Thu May 09 17:19:28 EDT 2002 | davef
Can�t help you with the article that you read. Other places to start are: * 2221, 7.2 Heat Dissipation Considerations, 7.3 Heat Transfer Techniques, and 8.1.10 Heat Dissipation * 2222, 9.1.2 Thermal Relief In Conductor Planes
Electronics Forum | Thu May 02 20:56:25 EDT 2002 | clunier
I remember reading a magazine article a few years ago that discused using the copper area of a pcb to transfer heat away from large SMT devices. Does anyone know of this article or something similar that I can obtain. The article covered copper area,
Electronics Forum | Fri Jun 06 18:44:26 EDT 2003 | davef
No, no. It's koscher to have thermal planes. You just need to: * Work with your fabricator to keep the layup balanced. * Relieve the plane so that it doesn't cause assembly problems. While probably not directly for your part, it gives a starting p
Electronics Forum | Mon Oct 21 11:49:20 EDT 2002 | sueph
Mike, We are currently wave soldering several assemblies with with a lot of ground plane. The soldering handbook we have in house suggests a preheat temp for metal core multilayer boards of 230 to 270 degrees F' (110 to 130 C'). It was scary at fir
Electronics Forum | Sun Oct 20 19:42:29 EDT 2002 | sjpence
Like Russ, I am also curious about the 100% fill requirement. On any thick, high mass board the key is getting as much heat as possible into the board. If you get the board to the proper temperature, solder will flow just about anywhere. As an alte
Electronics Forum | Fri Jun 06 16:11:25 EDT 2003 | RF Lurker
I understand that there may not be a lot of material on this, as most threads I've seen discourage doing it. It goes against DFM to do it. But I wish to use a large copper area instead of heat sink and thermal epoxy to cool a regulator. But I can'
