Electronics Forum | Tue Jun 04 17:10:13 EDT 2002 | davef
First, �flash gold� is very loose language. It means different things to different people. �Flash� gold is a thin coat of immersion gold. Imm gold self-limits at ~0.3um[12uin]. And fabs put-down �flash� prior to electroplating thicker gold for wi
Electronics Forum | Mon Aug 16 20:32:10 EDT 2004 | davef
First, we didn't say "electrolytic soft gold with a minimum thickness of 5-8 of Au". We said, "'electrolytic soft gold' thickness 5 to 8uin". FOCUS. ;-) Second, we're unaware of an industry accepted specification that you can reference. IPC-2221
Electronics Forum | Thu Jan 09 15:19:41 EST 2014 | davef
For a typical wear surface application [millions of wipes], I agree with hege. You need to be talking electrolytic gold, NOT immersion gold. IPC-2221 says something like ... For edge connectors and areas not to be soldered: * Nickel - 2.5um [~100uin]
Electronics Forum | Wed May 30 17:49:49 EDT 2001 | davef
You are correct. IPC wants you to pay for that standard, regardless if you get a hard copy or download it. Generally, it�s pretty boring stuff for production types. [Although, you will recognize some of the goofy things your designers have done to
Electronics Forum | Wed Oct 24 18:09:44 EDT 2001 | davef
Allowing the board fabricator to define the board you expect to receive is fine, as long as they do a good job. Regardless of the existence of a clear product definition or not, it�s reasonable for you to argue that your receipts must meet the requi
Electronics Forum | Wed Jan 09 12:20:00 EST 2002 | mregalia
Thanks for cluing me into IPC-2221. Though the numbers they give seem to contradict what I have learned from people working with the materials. At least I now know where the guideline for a max of 30 microinches of gold for soldering comes from. But
Electronics Forum | Fri Nov 25 15:52:40 EST 2011 | davef
"IPC-2221 - Generic Standard On Printed Board Design" talks to fiducials. Anther take on fiducials says they shall meet the following requirements. * Make fiducials 1 - 1.5 mm diameter circle. * Cover fiducials with tin. * Keep solder mask opening at
Electronics Forum | Mon Dec 13 00:48:33 EST 1999 | armin
Hi All I have a 0.7 mm diameter hole for vias, what�s the minimum annular ring for this hole diameter? What�s the term unsupported and supported holes refer to in IPC-2221 9.1.2 Annular Ring Requirements? I have a proto-type PCB (designed by our R&
Electronics Forum | Tue Dec 14 22:17:33 EST 1999 | Dave F
Armin: How ya doin� bud? CK gives good advice, but I'd like to take a bit of a different angle. Q1. For 0.7 mm (0.027in) diameter hole for vias, what�s the minimum annular ring for this hole diameter? Depends on what you�re trying to do. For in