Paul, Forgot the yield question. In a qualified, well process managed board shop very high yields are achieved (over 90%) up to 16 layers - piece of pie. For those in the 4 to 8 layer range, in production, over 95% yields are common depending on what you need again as size, features, hole sizes, via types, electrical characteristics, etc. Earl ----- Original Message ----- From: Paul Klasek <[log in to unmask]> To: <[log in to unmask]> Sent: Friday, August 27, 1999 4:25 PM Subject: Re: [TN] In Circuit Test > interesting , how thick is 52 ? (just curious) . > Earl we have the layers cost dilemma here : > What would be ratios of yields and costs from simple double sided FR4 ; > to 4 layers, 6, 8, >>> etc. ? > > And why even's only ; no odd layers ever ? > > thanks paul > > > -----Original Message----- > From: Enter your name here [mailto:[log in to unmask]] > Sent: Saturday, 28 August 1999 8:22 > To: [log in to unmask] > Subject: Re: [TN] In Circuit Test > > > Your 2 cents noted. No biggy, but we build bare boards up to 52 layers and > loaded cost over too many thousands. Even our cheap stuff ain't cheap. DFM > and T is critical. It just can't happen without concurrent engineering > including all responsible "experts" from design through test. > > Earl Moon > ----- Original Message ----- > From: Darrel Therriault <[log in to unmask]> > To: <[log in to unmask]> > Sent: Friday, August 27, 1999 11:35 AM > Subject: Re: [TN] In Circuit Test > > > > TechNet.... > > > > I'd like to put in my $.02 for DFT...... > > > > We specify 100% netlist coverage for ICT unless there is a compelling > design > > reason why a net can not be accessed. It's part of our Mfg DFT > requirements. > > > > The rationale.....our boards are expensive and complex. Having to scrap > > out or spend > > a lot of debug time at Functional costs a lot more in time and resources > > then adding > > some test points or taking up a little more real estate or adding a > > layer. I think if you > > look at the cost implication of production and service/customers it works > > out to a > > much bigger advantage to have ICT at the highest level possible. > > > > DT > > > > ############################################################## > > TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c > > ############################################################## > > To subscribe/unsubscribe, send a message to [log in to unmask] with > following text in > > the body: > > To subscribe: SUBSCRIBE TECHNET <your full name> > > To unsubscribe: SIGNOFF TECHNET > > ############################################################## > > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for > additional > > information. > > If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or > > 847-509-9700 ext.5365 > > ############################################################## > > ############################################################## > TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c > ############################################################## > To subscribe/unsubscribe, send a message to [log in to unmask] with following > text in > the body: > To subscribe: SUBSCRIBE TECHNET <your full name> > To unsubscribe: SIGNOFF TECHNET > ############################################################## > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > information. > If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or > 847-509-9700 ext.5365 > ############################################################## > > ############################################################## > TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c > ############################################################## > To subscribe/unsubscribe, send a message to [log in to unmask] with following text in > the body: > To subscribe: SUBSCRIBE TECHNET <your full name> > To unsubscribe: SIGNOFF TECHNET > ############################################################## > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > information. > If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or > 847-509-9700 ext.5365 > ############################################################## ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################