You guys are a riot... "Black Pad" is a defect of ENIG boards that is a separation of solder joints formed to the surface of the electroless nickel underplate. This is commonly attributed to excessive phosphorous in the electroless nickel (i.e. nickel electroless bath out of control). However, any kind of nickel contamination (phosphorous or not) that results in the failures characterized here, are often reported as "black pad" failures.
http://www.empf.org/empfasis/feb04/0204help.htm Bill -----Original Message----- From: Brian Guralnick [mailto:[EMAIL PROTECTED] Sent: Monday, August 13, 2007 11:46 AM To: Protel EDA Discussion List Subject: Re: [PEDA] Black Pad Actually, I once designed a PCB with a choice of TO-220 & DPak regulators. The +5 output was fed through the TO220's +5 pad which fed the power-plane which had thermal reliefs. Without burning out the thermal reliefs, they made just enough heat generated around them to make the unused TO220 pad black. Eventually, the thermal reliefs would burn out. Brad Velander wrote: > Brian, > That must be the black pad condition that follows the vaporized traces? 8^> > > Sincerely, > Brad Velander > Senior PCB Designer > Northern Airborne Technology > #14 - 1925 Kirschner Road, > Kelowna, BC, V1Y 4N7. > tel (250) 763-2232 ext. 225 > fax (250) 762-3374 > > > -----Original Message----- > From: Brian Guralnick [mailto:[EMAIL PROTECTED] > Sent: Monday, August 13, 2007 8:56 AM > To: Jeff Condit; Protel EDA Discussion List > Subject: Re: [PEDA] Black Pad > > > Before, or, after powering up of the PCB? > ____________________ > Brian Guralnick > Vergent Technologies Inc. > 438 Brahms Ave. > Dollard Des Ormeaux > Quebec, Canada > H9G 2S6 > (514) 624-4003 > [EMAIL PROTECTED] > > > > > ____________________________________________________________ > You are subscribed to the PEDA discussion forum > > To Post messages: > mailto:[email protected] > > Unsubscribe and Other Options: > http://techservinc.com/mailman/listinfo/peda_techservinc.com > > Browse or Search Old Archives (2001-2004): > http://www.mail-archive.com/[EMAIL PROTECTED] > > Browse or Search Current Archives (2004-Current): > http://www.mail-archive.com/[email protected] > > -- ____________________ Brian Guralnick Vergent Technologies Inc. 438 Brahms Ave. Dollard Des Ormeaux Quebec, Canada H9G 2S6 (514) 624-4003 [EMAIL PROTECTED] ____________________________________________________________ You are subscribed to the PEDA discussion forum To Post messages: mailto:[email protected] Unsubscribe and Other Options: http://techservinc.com/mailman/listinfo/peda_techservinc.com Browse or Search Old Archives (2001-2004): http://www.mail-archive.com/[EMAIL PROTECTED] Browse or Search Current Archives (2004-Current): http://www.mail-archive.com/[email protected]
