Electronics Forum | Tue Jul 02 02:50:55 EDT 2002 | ianchan
Hi mates, was going thru the IPC-A-610C Standards, and noted BGA voids stands somewhere between 10%-25% voids permissible in the solder "ball" bump, after reflow process. Was wondering, hypothetical case study, is there any specification for voids
Electronics Forum | Wed Feb 26 17:05:42 EST 2003 | davef
Q1: Are the markings on resistors the actual value? A1: Generally, resistor marking indicates the value of the device, where the first two digits are the value and the third digit is the multiplier. Q2: Do AOI machines look for these markings or do
Electronics Forum | Thu Mar 15 03:24:48 EST 2001 | Scott B
We are currently having a conflict of opinion with our QA department regarding the very few occurences we have of chip resistors being soldered upside down (i.e. the resistive element towards the board). IPC-A-610C para 12.3.2 specifies that this co
Electronics Forum | Thu May 23 03:10:43 EDT 2002 | ianchan
Hi mates, need your advise here. we have solderballs on a model due to neglect by stubborn folks to follow issued process control instructions. the post-reflow PCBA has solderballs stuck in the NC flux residue and is not in compliance to IPC-A-610
Electronics Forum | Mon Oct 28 18:59:25 EST 2002 | tkenny007
Specs for Bow and Twist for PCBs (IPC-A-610C, 10.6. There may be an update by now). I also have a note in our quality guide referencing (IPC-TM-650, 2.4.22) and (MIL-STD-105D). In summary, a PCB should not bow more than 0.040" with all four corner
Electronics Forum | Mon Apr 10 22:32:14 EDT 2000 | Dave F
Mark: If you're looking for a baseline document for judging the acceptability of: * Mechanical assembly * Component installation * Soldering * Cleanliness * Marking * Coating * Laminate condition * Discrete wiring * Surface mounting of components .
Electronics Forum | Thu Mar 15 08:16:28 EST 2001 | davef
In a similar conversation ... Alex Krstic, NovAtel Inc. said ... Hello all. We recently received some boards with some of the chip resistors placed with their resistive elements towards the board. J-STD-001B and C view this as violation for both Cl
Electronics Forum | Fri Apr 04 09:28:59 EST 2003 | davef
Q1: Anyone has any ideas on how this post-SMT reflow solder joint could have changed to whitish joint? A1: Dunno. You need to tell us more. For instance: * What is the appearance of this white residue? [eg, glassy / coarse, milky colored / opaque,
Electronics Forum | Mon Apr 22 20:55:00 EDT 2002 | ianchan
Hi, this is not really a technical solution, just a feedback. we too have a model series using the same WS paste type. it gives a dull solder joint with white residue that can be marginally removed after post-DI water rinse (ie. not 100% removed).
Electronics Forum | Mon May 14 17:12:20 EDT 2001 | davef
Continuing along the path that Brian took ... IPC-7525 gives design guideline for stepped stencils. It goes something like: * Stepped area SB GT 25 thou from pads located on the greatest thickness of the stencil * Pads in stepped area SB GT 35 tho
