Electronics Forum | Fri Jul 24 07:43:56 EDT 2009 | davef
Your customer is correct. You are doing something wrong in your hand soldering process. Solder balls are a process indicator. Areas to assess are: * Moisture content of the bare board * Thickness of the copper plating in the through holes * Temperatu
Electronics Forum | Fri Apr 17 14:08:44 EDT 1998 | Earl Moon
| Currently I am in the buisness of soldering bare die to the top surface of a copper heat sink. Is any one else | have some exprience in this process that can help. We heat a copper slug through a contolled atmosphere, place a preform then a bare
Electronics Forum | Fri Feb 19 09:20:01 EST 1999 | Stefan Witte
If the fiducials are rejected from the vision system, I would not relay on the accuracy of the position. Again, I would like to point out that the circle shape has a somewhat sinoid contrast in X- and Y- direction ( same as a diamond shape, but recta
Electronics Forum | Fri Feb 19 14:44:24 EST 1999 | Lance A. Smalley
You don't say what kind of machine you are using but several just use the edge of fiducials to determine area (and centers). If you are teaching in binary and have the ability to select a decision level (threshold), use a level half way between loss
Electronics Forum | Sat Feb 20 09:41:51 EST 1999 | Andy
| We are using .040" diameter fiducials (global and local) on our boards. They are solder covered and HASL. I get batches of boards where the p&p vision system has trouble reading the fiducial. The fiducial looks dark on the screen. The board ven
Electronics Forum | Fri Oct 16 21:17:04 EDT 1998 | Scott McKee
| | With current soldering of stranded wires to pcb assy's the wire tends to be very brittle and can break with very little movement of the wire. We use a low residue cored wire. Anybody with advice or who has seen a similar problem/knows how to over
Electronics Forum | Tue Aug 27 22:07:45 EDT 2002 | davef
Pad. Land. A portion of a conductive pattern used as a termination area. Metal surrounding a hole on a printed circuit board. Mask. A material applied to allow selective etching, plating, or protection of the surface of a printed circuit board.
Electronics Forum | Sun Apr 15 18:06:16 EDT 2007 | greg york
You may need slightly longer dwell times and a little more heat in the reflow and wave to ensure proper alloying/wetting. Also consider if you are using a nickel doped and high copper alloy on bare boards in Leaded wave solder bath you will pick up c
Electronics Forum | Tue Jul 22 03:56:24 EDT 2003 | A.G.
Are there existing acceptability dedicated criteria for ALIVH bare boards? (Equivalent to IPC-A-600) In particular, how can we assess copper foil cracking after thermal stress?
Electronics Forum | Fri Aug 14 07:27:42 EDT 1998 | Earl Moon
| | Hi, can you please tell me how to make green coating and through-hole plating of PCB? Thanks! | | Xingsheng | Xingsheng: Welcome. | Bible on PCB fabrication: Printed Circuits Handbook, Clyde Coombs, McGraw-Hill | Web resources: http://www.pw
