Electronics Forum | Fri Mar 07 14:09:16 EST 2003 | davef
Q1: What are the recommended stencil apertures for a TSOP40. Lead pitch 0.48mm & lead width 0.21mm. A1: We've talked about this previously here on SMTnet, for instance check the fine SMTnet Archives: http://www.smtnet.com//forums/index.cfm?fuseactio
Electronics Forum | Fri Mar 07 15:20:11 EST 2003 | davef
O'Connor: IPC-A-610, section 12.4.4 SMT Soldering Anomolies - Nonwetting was added primarily to accomidate OSP boards. Heated flux is used to remove the 'lacguer'. So, you end-up with a copper colored border [or shadow] around the pads, where there
Electronics Forum | Thu Mar 06 16:34:54 EST 2003 | msivigny
Hello gregp, IPC released 9850 on October 22, 2002 after the industry came together to standardize a method to determine placement capability as it relates to placement speed. As I'm sure you are aware, the standard gives placement machine manufactur
Electronics Forum | Wed Mar 12 10:34:42 EST 2003 | Stephen
I want to be clear. You are talking about buying fully populated cards? And not just bare boards. Approach different CM's and compare contracts. You can pretty much get anything from "build from kit" where all the CM does is assembly, to complete s
Electronics Forum | Mon Mar 10 16:29:34 EST 2003 | kenBliss
You can call it anything you want. At the end of the day what matters is what you are able to produce in a given period, say 8 hours. How many components where placed during that time. Most engineers do not fully understand that there is generally
Electronics Forum | Mon Mar 10 10:14:10 EST 2003 | pjc
Most pre-reflow AOI systems today can easily keep up with production line beat rates. Pre or Post reflow AOI is the difference between process control vs. defect screening, in my opinion. Pre reflow repairs cost much less than post. Pre AOI is for
Electronics Forum | Tue Apr 01 11:50:08 EST 2003 | rdr
Dave, thanks for the info. This sounds like it would verify the presence of an open. We have verified that these balls are open and I am trying to figure out if we are fracturing or not wetting. causing these opens. I would use the die method on ne
Electronics Forum | Tue Apr 01 17:29:58 EST 2003 | davef
R1: So if I understand you right, it could be possible that gold dissolved, but the ball still didn't wet to the underlying nickel. D1: Correct. The gold dissolves into the solder first. The solder wets to the nickel second. If you nickel is corro
Electronics Forum | Fri Apr 18 13:47:19 EDT 2003 | davef
Brian What did we recommend? We just gave you a link so that you can see how to get your pictures on-line, so that we can see what�s going on. Anyhow, if we understand what you saying, [We're slow today. So, please be patient.] your situation is:
Electronics Forum | Tue Apr 29 09:43:30 EDT 2003 | davef
With a nickel barrier and 'tin' plating, reconsider your reflow recipe to reduce the leaching of the termination into the solder during reflow. Points are: * In designing a reflow temperature recipe, it is important that the temperature be raised at
