Acceptance sample size

# Acceptance sample size

Given a certain number of known failures and target defective parts per million, the Acceptance Sample Size calculator can provide a sample size for testing with a certain degree of confidence. Typical value for confidence level is 60 percent.

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### Purpose

For a specified target DPPM at a given confidence level and observed or assumed number of fails, the calculator provides sample size required.

### Equation

\begin{aligned} \mathbf{SS} = \frac{ \mathbf{CHISQ.INV} ( {\mathbf{CL}, 2* \mathbf{fails} + 2}) }{ \frac{2 * \mathbf{DPPM}}{10^6}} \\ \end{aligned}

DPPM - Defective Parts per million

CL - Confidence Level represented as a decimal

SS - Sample size

Fails - Number of failures in your sample size

Important Limitations on Use of Data

TI provides this data for your convenience. However, there are significant limitations of its usefulness as an indicator of how TI parts (including related software) may perform when used in various applications.

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