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Defect Per Unit (DPU) versus DPMO

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James

#48722

Defect Per Unit (DPU) versus DPMO | 29 March, 2007

Hi,

I have 1 customer asking us to do product Defect Per Unit(DPU) real time monitoring. I am confused why this is needed since we already have process DPMO..

Rgds, James

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#48762

Defect Per Unit (DPU) versus DPMO | 29 March, 2007

We have Military and Medical companies that want us to track that so that if a particular unit fails we can determin if rework was the cause. Otherwise you are dealing with a QM that thinks they're real smart and your not! I suspect if you ask them why they'll tell you. From there it becomes what are they willing to pay for. We give our customer most anything they are willing to pay us to do. (I did say most anything!)

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#48763

Defect Per Unit (DPU) versus DPMO | 29 March, 2007

I'm curious if you take specific actions based on the results of your DPMO.

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#48766

Defect Per Unit (DPU) versus DPMO | 29 March, 2007

All depends on the product. I say that because some stuff just isn't worth the effort, you other CM's know what I'm talking about. We do a review on every run after it is complete and there are many actions that can be taken. We always first focus on the top 3 defects then we look for DFM issue and feed that back to the customer. We are generally a high mix operation so it is very difficult to drive defects to 0 but if you alway focus on fixing your top three you can develop some pretty good processes.

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#48773

Defect Per Unit (DPU) versus DPMO | 30 March, 2007

Alot of QM's and QE's are typically failed Engineers who lack common sense. They don't understand that measuring in DPMO's (versus DPU's) "normalizes" your data for Printed Circuit Board Assemblies (PCBA's) so that if you have 10 defects on a PCBA that has 100 opportunities versus 10 defects on a PCBA that has 100,000 opportunities, you'll still be comparing apples to apples.... Sure DPU may work for other things, but the QM's and QE's don't get it.

IPC7912 & IPC9621 are the industry standards for how DPMO is calculated.

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