Statistical process Control and evaluation CPK, SPC, PPM

CPK (Process capability index)--process capability index

SPC (statisical Process Control)--analysis of process statistics controlled state

PPM (Parts Per Million)--million-percent

The first chapter exercises

1.1 What are the problems in the production of modern electronic components, conventional reliability assessment methods (sampling test, Reliability life test, field use data accumulation, etc.)?

Sampling methods do not distinguish between high-level product quality differences.

When the reliability life test is not 10FIT, the number of samples required is up to tens of thousands of, and the cost of the sample test is too high.

field  and accumulation methods lag. The newly developed product must be used for a period of time before the conclusion can be reached.

1.2 describes the meaning of the "bathtub curve" with the change of component failure rate over time, and the "design and manufacture" and "screening test" respectively, which function to the quality and reliability of components according to the "bathtub curve".

The failure curve of electronic components varies with time.

Through "Test re-screening" can only eliminate the early failure of the product, and can not reduce the failure rate during accidental failures. Therefore, screening can only improve the reliability of product use, and can not really improve the product's "intrinsic quality and reliability."

Reliability is designed and manufactured.

Component manufacturers through the test screening can only eliminate the early failure of the product, only through the design and manufacturing to reduce the failure of the accident efficiency, delay the occurrence of loss failure time, and truly pray to improve the intrinsic quality and reliability of the role of components.

Therefore, the traditional method of evaluating the final product of the detachment can be changed, and the intrinsic quality and reliability of the component products are evaluated by the evaluation of the design and process.

1.3 What is the relationship between component reliability and component production yield? How do you understand the relationship that exists between them?

1.4 What is the role of CPK, SPC, and PPM technology for component manufacturers?

1.5 machine factory in the procurement of components, why require the component manufacturing plant to implement CPK, SPC and PPM technology, and required to provide CPK, SPC, and ppm data?

Statistical process Control and evaluation CPK, SPC, PPM