Michael Are you talking process defects only, or including test failures that could not be caught downstream? I'll assume you are considering process defects only. I believe that you have to consider the device types on the board in any target - as a crude example, a board covered with 1206 resistors is easier than 0603's, and a BGA will give you a better process yield (typically) than a big QFP module. And the other twist is the inspection criteria - an amazing yield at class 1 is not so hot at class 3. If it were me I would base my cut-off on a decreasing target that is realistically based on past history, expectations, board complexity, design issues, and rational thought. At another employer I was on the other side of this fence, with a customer who had a target and didn't care how well thought out it was, it was THE target and that was it. good luck! - Graham Collins -----Original Message----- From: Michael Forrester [mailto:[log in to unmask]] Sent: Tuesday, September 08, 1998 5:15 PM To: [log in to unmask] Subject: [TN] Acceptable PPM Defect Rate I am a floor shop engineer for a Digital Oscilloscope line. Our PCA's have mixed technology and down to 20 mil. (typically 25 mil and above). Typically the boards are 12" X 12" with approx. 10K chances for error (ie. Comp. Count + Lead Count). Typically 10% of the parts are located on the secondary side. I would like to know what the industry considers an acceptable defect rate in PPM coming into a subassembly test department, after an in-house QA lot inspection, and rate from an outside PCA house. My QA department has a certain threshold in mind before something is a "problem". I want to know if their threshold is at least in the ballpark of the industry. Thank you. Best Regards, Mike Forrester LeCroy Corp. [log in to unmask] ################################################################ TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################